123rc/medical_text huggingface dataset:
Relative importance of activation sequence compared to atrioventricular synchrony in left ventricular function. This study evaluated the relative hemodynamic importance of a normal left ventricular (LV) activation sequence compared to atrioventricular (AV) synchrony with respect to systolic and diastolic function. Twelve patients with intact AV conduction and AV sequential pacemakers underwent radionuclide studies at rest and Doppler echocardiographic studies at rest and during submaximal exercise, comparing atrial demand pacing (AAI) to sequential AV sensing pacing (DDD) and ventricular demand pacing (VVI). Studies at rest were performed at a constant heart rate between pacing modes, and the exercise study was performed at a constant heart rate and work load. Cardiac output was higher during AAI than during both DDD and VVI (6.2 +/- 1 vs 5.6 +/- 1 and 5.3 +/- 1 liters/min, p less than 0.05). LV ejection fraction was likewise higher during AAI (55 +/- 12 vs 49 +/- 11 vs 51 +/- 13, p less than 0.05). VVI with or without AV synchrony was associated with a paradoxical septal motion pattern, resulting in a 25% impairment of regional septal ejection fraction. In addition, LV contraction duration was more homogenous during AAI. Peak filling rate during AAI and VVI was higher than during DDD (2.86 +/- 1 and 2.95 +/- 1 vs 2.25 +/- 1 end-diastolic volume/s; p less than 0.05). During VVI, the time to peak filling was significantly shorter than during both AAI and DDD (165 +/- 34 vs 239 +/- 99 and 224 +/- 99 ms; p less than 0.05).
Bleeding from duodenal lymphangiectasia. An 8 year old girl with recurrent upper gastrointestinal bleeding was found to have localised duodenal lymphangiectasia by fibreoptic endoscopy. She did not show physical signs or laboratory evidence of significant enteric protein loss. A low fat diet seemed to prevent further bleeding. Duodenal lymphangiectasia may be associated with gastrointestinal bleeding in children.
Detection of Ki-67 proliferation rate in breast cancer. Correlation with clinical and pathologic features. In situ determination of proliferative activity was performed on 203 breast cancers by use of Ki-67 monoclonal antibody and immunohistochemical methods. Tumor proliferation rate was analyzed and correlated to tumor size and nodal status. The relationship between Ki-67 proliferative activity and nuclear estrogen receptor content was also investigated on adjacent tissue sections. Ki-67 values ranged from 1 to 75%, with a median value of 10%. Premenopausal patients had greater Ki-67 values (median value, 14.1%) than postmenopausal ones (median value, 9.8%). The authors observed no correlation with lymph nodal involvement, whereas a statistically significant relationship with tumor size was found (P less than 0.01). An inverse correlation (Spearman's coefficient = -0.56; P less than 0.001) was seen between Ki-67 values and nuclear estrogen receptor content. These results, similar to those reported for other kinetic measurements, suggest that in situ detection of Ki-67 proliferation rate is a useful method for obtaining cell cycle information. Follow-up studies will be needed to assess an eventual prognostic relevance.
Tables for estimation of individual risks of fetal neural tube and ventral wall defects, incorporating prior probability, maternal serum alpha-fetoprotein levels, and ultrasonographic examination results. Tables are provided for estimation of the risk of open spina bifida in patients who have elevated maternal serum alpha-fetoprotein levels but normal results on detailed anatomy ultrasonographic scan. Risks are provided for various prior population risks, for various levels of elevated maternal serum alpha-fetoprotein, and for various assumptions about the sensitivity of ultrasonographic examination. The formula used is based on sequential multiplication of odds with the use of Bayes' theorem, but an arbitrary reduction (to the power of 0.5) in the degree to which ultrasonographic information modifies the odds has been made to allow for the nonindependence of ultrasonography and maternal serum alpha-fetoprotein tests. The wide range of resulting risks shows that the decision to offer amniocentesis after a negative scan should be individualized.
Central nervous system haemangioblastoma: a clinical and genetic study of 52 cases. Fifty two cases of haemangioblastoma were reviewed for their clinical, genetic and prognostic features. Of 34 patients with apparently isolated cerebellar lesions, postoperative outcome was good in 79%. Six isolated spinal lesions presented more insidiously and morbidity was related to incomplete resection. Twelve (23%) of the patients definitely had von Hippel-Lindau disease (VHLD). The true proportion may be higher as this diagnosis was not definitely excluded in many of the remainder; only ten patients with seemingly isolated cerebellar tumours were appropriately investigated and two had evidence of VHLD. Four out of 26 cases (15%) with apparently completely resected, isolated, cerebellar lesions later developed recurrent tumours. Brainstem and supratentorial haemangioblastomas were rare and were always associated with VHLD. The cerebellar or spinal haemangioblastomas due to VHLD had no distinctive clinical features compared with isolated tumours and there was considerable overlap in age of onset between the two groups of cases. All patients with an apparently isolated CNS haemangioblastoma should be investigated for evidence of von Hippel-Lindau disease.
Validation of intermediate end points in cancer research. Investigations using intermediate end points as cancer surrogates are quicker, smaller, and less expensive than studies that use malignancy as the end point. We present a strategy for determining whether a given biomarker is a valid intermediate end point between an exposure and incidence of cancer. Candidate intermediate end points may be selected from case series, ecologic studies, and animal experiments. Prospective cohort and sometimes case-control studies may be used to quantify the intermediate end point-cancer association. The most appropriate measure of this association is the attributable proportion. The intermediate end point is a valid cancer surrogate if the attributable proportion is close to 1.0, but not if it is close to 0. Usually, the attributable proportion is close to neither 1.0 nor 0; in this case, valid surrogacy requires that the intermediate end point mediate an established exposure-cancer relation. This would in turn imply that the exposure effect would vanish if adjusted for the intermediate end point. We discuss the relative advantages of intervention and observational studies for the validation of intermediate end points. This validation strategy also may be applied to intermediate end points for adverse reproductive outcomes and chronic diseases other than cancer.
Narrow QRS ventricular tachycardia. OBJECTIVE: To determine the frequency and clinical characteristics of narrow QRS ventricular tachycardia (QRS duration less than or equal to 0.11 seconds). DESIGN: Consecutive survey of patients with ventricular tachycardia. SETTING: Tertiary, referral-based arrhythmia service at a university medical center. PATIENTS: Sequential sample of patients with inducible ventricular tachycardia who had a 12-lead electrocardiogram of the tachycardia available for review. MEASUREMENTS AND MAIN RESULTS: Of 106 patients with ventricular tachycardia, 5 (4.7%; 95% CI, 2.1% to 10.6%) had ventricular tachycardia with a QRS duration less than or equal to 0.11 seconds. Three of the five patients were previously incorrectly diagnosed as having supraventricular tachycardia. All five patients had at least two electrocardiographic findings other than QRS duration to suggest ventricular tachycardia. CONCLUSIONS: Narrow QRS ventricular tachycardia should be considered in the differential diagnosis of narrow QRS tachycardias. Electrocardiographic findings other than QRS duration are usually present to suggest the diagnosis.
Prostacyclin and prostaglandin E2 mediate reduction of increased mean arterial pressure during cardiopulmonary bypass by aspiration of shed pulmonary venous blood. Increased mean arterial pressure during the aortic crossclamp period while on cardiopulmonary bypass was usually treated by us with hypotensive drugs. We noticed, however, that aspirating shed excess pulmonary venous blood from the open pleural cavities causes an immediate reduction in mean arterial pressure, obviating the need for any further pharmaceutical intervention. In this study we investigated the relationship between the reduction in mean arterial pressure and the levels of prostacyclin and prostaglandin E2 in the peripheral and pulmonary venous blood. Ten men undergoing coronary bypass operations had 21 episodes of increased mean arterial pressure (106.9 +/- 11.4 mm Hg) during aortic crossclamping, which was reduced to 67.4 +/- 11.4 mm Hg (p less than 0.001) only by aspirating a mean of 490 ml (range 150 to 1100 ml) of pulmonary venous blood from the pleurae back into the circulation. Mean peripheral prostacyclin level, measured as 6-keto-prostaglandin F1 alpha, and prostaglandin E2 level, both measured by radioimmunoassay technique, were significantly lower at peak mean arterial pressure (419 +/- 180 and 59.5 +/- 21.2 pg/ml) than at lowest mean arterial pressure (632 +/- 271 and 96.7 +/- 52.4 pg/ml for 6-keto-prostaglandin F1 alpha and prostaglandin E2, respectively; p less than 0.001). Prostaglandin F1 alpha and prostaglandin E2 levels in the aspirated pulmonary venous blood were 2309 +/- 3098 pg/ml and 749 +/- 909 pg/ml, respectively. The hypotensive effect of shed pulmonary venous blood that is aspirated back from the pleurae into the circulation seems to be mediated by the high levels of prostacyclin and prostaglandin E2, both powerful vasodilators.
Cerebral effects of sevoflurane in the dog: comparison with isoflurane and enflurane. The cerebral effects of sevoflurane were compared in dogs with those of enflurane and isoflurane. Initially, the minimum alveolar concentrations (MAC) of sevoflurane and enflurane were determined and the electroencephalographic (EEG) responses to increasing doses of sevoflurane (1.5, 2.0 and 2.5 MAC) or enflurane (1.5 and 2.0 MAC) in unparalysed animals were examined. Administration of sevoflurane was not associated with seizure activity at any concentration either during normocapnia (PaCO2 5.3 kPa) or hypocapnia (PaCO2 2.7 kPa), even in the presence of intense auditory stimuli. All dogs anaesthetized with enflurane demonstrated sustained EEG and motor evidence of seizure activity induced by auditory stimuli at concentrations of enflurane greater than 1 MAC, particularly during hypocapnia. In a separate group of dogs, the effects of increasing concentrations of sevoflurane and isoflurane (0.5, 1.5 and 2.15 MAC) were compared directly on arterial pressure, cardiac output and heart rate, cerebral blood flow and the cerebral metabolic rate for oxygen (CMRO2) using the venous outflow technique. Sevoflurane, in common with isoflurane, had minimal effects on cerebral blood flow at the concentrations studied, but significantly reduced the CMRO2 at end-tidal concentrations sufficient to produce a burst suppression pattern on the EEG (approximately 2.15 MAC). Both sevoflurane and isoflurane significantly decreased arterial pressure in a dose-dependent manner, but neither drug significantly altered cardiac output.
Orthopedic complications. Compartment syndrome, fat embolism syndrome, and venous thromboembolism. Specialized education in the care of orthopedic patients includes an understanding of the common complications for which patients require monitoring. With a socioeconomic backdrop of decreasing hospital stays and prospective payment, patient care must be managed proactively. For all three complications presented, there are unique sets of risk factors that, when present, contribute to a high index of suspicion for morbidity. Clusters of symptoms have also been discussed representing the expected normal patterns. With this knowledge as a foundation, clinical application is essential to incorporate other salient aspects of individual situations. Nurses diagnose and treat human responses to health problems. The end result of human responses to injury or orthopedic conditions can be the development of complications. Stringent adherence to patient monitoring protocols can promote timely nursing interventions to prevent, minimize, or detect complications or treatment side effects. Although definitive treatment is often physician directed, nurses are in a key role to impact final patient outcomes.
A comparison of Ho's, International Union Against Cancer, and American Joint Committee stage classifications for nasopharyngeal carcinoma. Five hundred sixty-four nasopharyngeal carcinomas (NPC), mostly of undifferentiated histologic type, were studied for survival, distant metastasis, and local recurrence. All had computerized tomography of the nasopharynx and skull base (CT-NP) and fiberoptic nasopharyngoscopy for evaluation of the primary tumor. Regional disease was assessed by palpation. A computer data base was formed on presentation, containing all information required for staging according to Ho's, the International Union Against Cancer (UICC), and the American Joint Committee (AJC) classifications. The three were compared for their efficacy in predicting prognosis. Ho's classification was superior to the other two because its overall stages differed from one another more significantly in the actuarial survival (ASR), disease-free survival (DFS), and freedom from distant metastasis (FDM) rates, and its N staging was more accurate in predicting FDM. Stages T1 and T2 of UICC/AJC were similar in the freedom from local recurrence rate (FLR) and should be grouped together, equivalent to Ho's T1. A more even patients number distribution among the stages also favored the use of Ho's classification.
Familial paroxysmal kinesigenic ataxia and continuous myokymia. A large family with paroxysmal ataxia and continuous myokymic discharges is described. The disorder is of autosomal dominant inheritance. During attacks coordination of movements and balance are disturbed; often a postural tremor of the head and the hands and fine twitching in some of the facial and hand muscles are present. The attacks usually last a few minutes and may occur several times per day. They first appear in childhood and tend to abate after early adulthood. The attacks are frequently precipitated by kinesigenic stimuli similar to those in paroxysmal kinesigenic choreoathetosis. Their occurrence can be reduced or prevented by carbonic anhydrase inhibitors. Between attacks a slight postural tremor and ataxia was found in a few of the elderly affected members. Fine rippling myokymia was obvious in a few and could be detected on close inspection in about half of the adults. Electromyography (EMG) showed myokymic discharges in all affected members. The characteristics and reactivity of this myokymic activity suggest multiple impulse generation in the peripheral nerves.
Interpleural analgesia improves pulmonary function after cholecystectomy. The purpose of this study was to examine the effects of interpleural bupivacaine on analgesia and ventilatory capacity after cholecystectomy. Forty-two patients undergoing elective cholecystectomy were randomly assigned to two groups: one to receive interpleural administration of bupivacaine-adrenaline mixture (Group 1 = 22 patients) and the other standard administration of intramuscular meperidine (Group 2 = 20 patients) for postoperative pain relief. The intensity of pain was evaluated by a visual analogue scale (VAS) preoperatively as well as at 2, 8, 24 and 48 hr postoperatively. At the same time, FVC and FEV1.0 measurements were obtained for all patients. The group given interpleural bupivacaine had better pain relief with mean VAS of 0.6 +/- 0.9 (mean +/- SD) 1.1 +/- 1.4, 0.6 +/- 0.9 and 0.8 +/- 1.2 compared with 5.2 +/- 2.2, 5.8 +/- 2.7, 5.5 +/- 2.2 and 4.5 +/- 1.8 for patients receiving meperidine (P less than 0.001). The patients in Group 1 also had larger FVC and FEV than those in Group 2: FVC 22 +/- 14.5 per cent vs 32 +/- 15.2 per cent (P less than 0.005), FEV1.0 25 +/- 15.5 vs 38 +/- 14.8 per cent (P less than 0.001) (mean +/- SD). We conclude that the interpleural analgesia can achieve better pain relief with greater ventilatory capacity than a standard analgesic regimen in the first two days after cholecystectomy.
Zinc and copper in breast cancer. A joint study in northern Italy and southern France. The relationship between breast cancer and two trace elements, zinc (Zn) and copper (Cu), was investigated by means of an hospital based case-control study at Milan (Italy) and Montpellier (France). Variables concerning dietary intake of Zn and Cu (in Milan) and their blood levels (both in Milan and Montpellier) were measured. Dietary intake, evaluated through a questionnaire of the dietary history type, and blood levels of Zn and Cu were measured in 261 cases and 261 controls. Cu blood level showed a contradictory tendency in the two samples (higher in controls in Milan, higher in cases in Montpellier), which tended to lessen after adjustment for related variables. No odds ratios (OR) in the different quantiles, nor X2 for trend reached statistical significance. A sharp difference was evidenced on the opposite with regard to Zn blood values in cases and controls. In both samples Zn mean values are significantly higher in cases than in controls, and the difference remains significant in the two samples even after adjustment for related variables. The pooled OR computed from the two samples, after adjustment for known risk factors and related variables, reaches in the fourth quartile a value of 9.5 (CI: 4.9-18.2). Dietary intake of the two minerals (measured only in Milan sample) showed no difference between cases and controls, but a stronger relationship between dietary and blood Zn was evidenced in cases with respect to controls. The authors suggest that the higher Zn level in cases might be related with an higher incorporation of Zn in cancer cases and that the same mineral might play a possible role in tumor growth promotion.
Results of surgical treatment of kidney cancer with solitary metastasis to contralateral adrenal. A large series of patients were reviewed in two major teaching institutions, and patients with a carcinoma of the kidney with a solitary metastatic deposit in the contralateral adrenal were identified. Their survival was analyzed and compared with the survival of those patients having a solitary metastatic deposit in other organs.
Multiple organ failure: inflammatory priming and activation sequences promote autologous tissue injury. Systemic inflammation promotes multiple organ failure through the induction of diffuse microvascular leak. Inflammatory cells such as neutrophils propagate this process. Tissue injury by neutrophils may be viewed as a normal process, inflammation, that has become uncontrolled and generalized. Multiple inflammatory stimuli synergistically promote neutrophil-mediated tissue injury in priming and activation sequences. In some settings, cellular priming is mediated by platelet-activating factor and can be prevented by platelet-activating factor antagonists. Inhibiting cellular priming could be efficacious in the therapy of multiple organ failure.
Cutaneous manifestations in patients with essential thrombocythemia. In a retrospective study of 268 patients with essential thrombocythemia, related cutaneous manifestations were found in 58 (22%). In 27 cases (10%) the related skin lesions were present at the time of the primary diagnosis of essential thrombocythemia. Hematomas, ecchymoses, petechiae, or purpura occurred in 24 (41%) of the 58 patients. Fifteen patients (26%) had erythromelalgia, in 11 of whom it was the initial complaint. Livedo reticularis, recurrent superficial thrombophlebitis, ischemic complications with gangrene, leg ulcers, or ulcers on the toes were other manifestations. Urticaria occurred in two patients, and Raynaud's phenomenon and necrotizing vasculitis were each observed in one patient. Platelet function may be abnormal, and this was found in 13 of 19 patients studied, 9 of whom had spontaneous platelet aggregation. Knowledge of the cutaneous manifestations in essential thrombocythemia may lead to its earlier detection. Prompt diagnosis of essential thrombocythemia is important because treatment may prevent severe hemorrhagic or thrombotic events.
Relationship of transfusion and infectious complications after gastric carcinoma operations. To determine the effect of transfusion on the incidence of postoperative infection, a retrospective cohort study of 196 patients who underwent surgery for gastric carcinoma in the period from 1985 through 1989 was carried out. Seventy-one patients (36.2%) developed postoperative septic complications; they had received an average of 4.2 blood units, as compared with 2.7 units received by patients not affected (p less than 0.0053). The hypothesis of dose-response relationship is supported by the Mantel-Haenszel test, as applied to the overall results (p less than 0.01) and the results grouped by duration of operation (p less than 0.02). Furthermore, logistic regression analysis shows transfusion to be an independent risk factor in the incidence of infection (p less than 0.01), as are antibiotic prophylaxis (p less than 0.015), urinary tract catheterization (p less than 0.002), and the duration of surgery (p less than 0.027). This significance is attained after adjustment for age, gender, period of evolution of symptoms; preoperative infection(s), number of white cells, hemoglobin level and total proteins on diagnosis, location of tumor, tumor, nodes, and metastasis staging, operative technique, drainage of the area of operation, enteral nutrition, and the histologic studies and macroscopic appearance of the tumor. This study is further evidence that transfusion may cause an increased incidence of postoperative infection.
Radioimmunoguided surgery using iodine 125 B72.3 in patients with colorectal cancer. Preliminary data using B72.3 murine monoclonal antibody labeled with iodine 125 suggested that both clinically apparent as well as occult sites of colorectal cancer could be identified intraoperatively using a hand-held gamma detecting probe. We report the preliminary data of a multicenter trial of this approach in patients with primary or recurrent colorectal cancer. One hundred four patients with primary, suspected, or known recurrent colorectal cancer received an intravenous infusion of 1 mg of B72.3 monoclonal antibody radiolabeled with 7.4 x 10 Bq of iodine 125. Twenty-six patients with primary colorectal cancer and 72 patients with recurrent colorectal cancer were examined. Using the gamma detecting probe, 78% of the patients had localization of the antibody in their tumor; this included 75% of primary tumor sites and 63% of all recurrent tumor sites; 9.2% of all tumor sites identified represented occult sites detected only with the gamma detecting probe. The overall sensitivity was 77% and a predictive value of a positive detection was 78%. A total of 30 occult sites in 26 patients were identified. In patients with recurrent cancer, the antibody study provided unique data that precluded resection in 10 patients, and in another eight patients it extended the potentially curative procedure.
Proximal posterior cerebral artery occlusion simulating middle cerebral artery occlusion. We describe 12 cases of acute stroke in which clinical features of proximal posterior cerebral artery occlusion simulated the clinical syndrome of middle cerebral artery occlusion. The majority of patients developed contralateral hemiparesis, homonymous hemianopia, hemispatial neglect, and sensory loss or sensory inattention. All 8 patients with dominant hemisphere lesions were aphasic. Accurate diagnosis in each case was achieved only after a head CT, showing occipital lobe, thalamic, and inferomesial temporal lobe infarction. "Cortical" signs are probably explained by thalamic involvement. Recognition of this syndrome has implications for management and prognosis.