123rc/medical_text huggingface dataset:
Mammography and early breast cancer detection. Screening mammography has been shown to reduce breast cancer mortality. Both film-screen mammography and xeromammography are highly sensitive and specific. Mammography accreditation programs assure physicians and patients that a facility provides mammography of the highest quality, using the lowest possible radiation dose. Mammographic signs of early cancer include a small mass, calcifications, architectural distortion and a neodensity. Dense tissue may result in a false-negative examination even when a cancer is palpable, with adverse effects if biopsy is delayed.
Cat-scratch disease. Acute encephalopathy and other neurologic manifestations. Seventy-six patients with neurologic complications of cat-scratch disease are discussed. Encephalopathy occurred in 61, while 15 had either cranial or peripheral nerve involvement. The average age of the patients with encephalopathy was 10.6 years (range, 1 to 66 years), and almost twice as many males as females were affected in contrast to patients with uncomplicated cat-scratch disease, in which the ratio was almost equal. Fever was not documented in 50% of patients with encephalopathy and only 26% had temperatures higher than 39 degrees C. Convulsions occurred in 46% and combative behavior in 40%. Lethargy with or without coma was accompanied by variable neurologic signs. Results of laboratory studies, including imaging of the central nervous system, were inconsistent and nondiagnostic. Biopsy tissue from 14 patients showed histopathologic findings compatible with cat-scratch disease. The "English-Wear bacillus" was demonstrated by the Warthin-Starry stain in 10 of 14 skin or lymph node specimens. Of the 15 patients without encephalopathy, two children with facial nerve paresis displayed cranial nerve symptoms and/or signs, 10 patients had cat-scratch disease neuroretinitis, and three women had peripheral neuritis. All 76 patients recovered within 12 months; 78% recovered within 1 to 12 weeks. There were no neurologic sequelae. Treatment consisted of control of convulsions and supportive measures. Commonly used antibiotics administered to more than half of the patients were apparently ineffective.
Centrifugal intensity and duration as countermeasures to soleus muscle atrophy. Mechanical acceleration is a countermeasure that may be employed to prevent atrophy of slow-twitch muscle during non-weight bearing. In the present study, daily centrifugation of rats for different durations (1 or 2 h) and at different gravitational intensities (1.5 or 2.6 G) was used to test whether mechanical acceleration could ameliorate the atrophy of the soleus muscle induced by non-weight bearing (tail-traction model). The soleus muscle atrophied 32% during 7 days of non-weight bearing without countermeasures. Centrifugation treatment did not completely prevent atrophy relative to precontrol wet weight of the soleus muscle. Non-weight-bearing groups receiving 2-h daily treatments of 1, 1.5, or 2.6 G had 48, 56, and 65%, respectively, of the atrophy observed in the non-weight-bearing-only group compared with the precontrol group. No evidence was obtained that centrifugation at 2.6 G was more effective than exposure to 1 or 1.5 G as a countermeasure to non-weight-bearing-induced atrophy of the soleus muscle.
Diagnostic efficiency of troponin T measurements in acute myocardial infarction BACKGROUND. The present study was designed to evaluate the efficiency of a newly developed troponin T enzyme immunoassay for the detection of acute myocardial infarction. METHODS AND RESULTS. The study comprised 388 patients admitted with chest pain and suspected myocardial infarction and 101 patients with skeletal muscle damage and additional suspected myocardial cell damage. Troponin T was elevated to more than twice the analytical sensitivity of the assay (0.5 microgram/l) in all patients with non-Q wave (range, 1.2-5 micrograms/l) and Q wave infarction (range, 3-220 micrograms/l). Troponin T appeared in serum as early as 3 hours after onset of pain in 50% of the patients and remained elevated in all patients for more than 130 hours, revealing release kinetics of both free cytosolic and structurally bound molecules. The diagnostic efficiency of troponin T was superior to that of creatine kinase-MB (98% versus 97%) and remained at 98% until 5.5 days after admission, if patients with unstable angina were excluded from analysis. In the 79 patients with unstable angina, troponin T was elevated (range, 0.55-3.1 micrograms/l) in at least one blood sample from each of 37 patients (56%). Circulating troponin T was correlated to the presence of reversible ST segment or T wave changes on the electrocardiogram (p less than 0.005) and to the frequency of in-hospital complications. In the 101 patients with skeletal muscle damage and suspected additional cardiac muscle damage, troponin T was the most useful test; its efficiency was 89% or 94% (depending on the discriminator value used) as compared with 63% for creatine kinase-MB. CONCLUSIONS. Thus, the data of the study indicate that the newly developed troponin T test improves the efficiency of serodiagnostic tools for the detection of myocardial cell necrosis as compared with conventionally used cardiac enzymes.
Petrosal sinus sampling: technique and rationale. Bilateral simultaneous sampling of the inferior petrosal sinuses is an extremely sensitive, specific, and accurate test for diagnosing Cushing disease and distinguishing between that entity and the ectopic ACTH syndrome. It is also valuable for lateralizing small hormone-producing adenomas within the pituitary gland. The inferior petrosal sinuses connect the cavernous sinuses with the ipsilateral internal jugular veins. The anatomy of the anastomoses between the inferior petrosal sinus, the internal jugular vein, and the venous plexuses at the base of the skull varies, but it is almost always possible to catheterize the inferior petrosal sinus. In addition, variations in size and anatomy are often present between the two inferior petrosal sinuses in a patient. Advance preparation is required for petrosal sinus sampling. Teamwork is a critical element, and each member of the staff should know what he or she will be doing during the procedure. The samples must be properly labeled, processed, and stored. Specific needles, guide wires, and catheters are recommended for this procedure. The procedure is performed with specific attention to the three areas of potential technical difficulty: catheterization of the common femoral veins, crossing the valve at the base of the left internal jugular vein, and selective catheterization of the inferior petrosal sinuses. There are specific methods for dealing with each of these areas. The sine qua non of correct catheter position in the inferior petrosal sinus is demonstration of reflux of contrast material into the ipsilateral cavernous sinus. Images must always be obtained to document correct catheter position. Special attention must be paid to two points to prevent potential complications: The patient must be given an adequate dose of heparin, and injection of contrast material into the inferior petrosal sinuses and surrounding veins must be done gently and carefully. When the procedure is performed as outlined, both inferior petrosal sinuses can be catheterized in more than 98% of patients. The complication rate is low, and the theoretical risk of major morbidity or death is less than 1% (neither has yet occurred, to our knowledge). The most common complication is groin hematoma.
Immunoblastic T-cell lymphoma presenting as an eyelid tumor. A 59-year-old white man presented with an ulcerating mass of the left upper eyelid of 6 months' duration. A biopsy specimen of the tumor was diagnosed as an immunoblastic T-cell malignant lymphoma. The lesion completely regressed after 4000 cGy of cobalt-60 radiation therapy. In the ensuing 33 months, multiple, widespread skin nodules of the same neoplasm developed including a right upper eyelid tumor. To the authors' knowledge, this is the first reported case of an immunoblastic T-cell lymphoma initially manifesting as an eyelid neoplasm.
Expression of ABH blood group antigens, Ulex europaeus agglutinin I, and type IV collagen in the sinusoids of hepatocellular carcinoma. The expression of blood group antigens (A, B, H, Lewis(a) and Lewis(b)), Ulex europaeus agglutinin I (UEA-I), factor VIII-related antigen, and type IV collagen on the sinusoids was examined immunohistochemically in 15 cases of hepatocellular carcinomas (HCC), 11 cases of cirrhosis, 12 cases of chronic active hepatitis, and in a control sample of 16 normal livers. Sinusoidal endothelial cells of HCC characteristically showed a diffuse and strong immunoreactivity to ABH blood group antigens in the specimen with a comparable ABO blood group. The sinusoidal endothelial cells were also diffusely and strongly positive for UEA-I receptors. In contrast, in cirrhosis and chronic active hepatitis a few sinusoidal endothelial cells were positive for ABH blood group antigens and UEA-I receptors. In normal livers, only a few sinusoidal endothelial cells were positive for ABH blood group antigens and UEA-1 receptors. Tests for factor VIII-related antigen and Lewis blood group antigens were almost negative on sinusoidal endothelial cells. Although type IV collagen was distributed diffusely in the space of Disse in these four groups, its expression was strongest in HCC. Blood vessels of portal tracts and fibrous septa were positive for ABH blood group antigens, UEA-1 receptors, factor VIII-related antigen, and type IV collagen, but negative for Lewis blood group antigens. These findings suggest that some sinusoidal endothelial cells undergo "capillarization" in cirrhosis and chronic active hepatitis, and that the majority of sinusoidal endothelial cells of HCC have phenotypic characteristics of capillaries.
Bile acids in human plasma interfere with cholecystokinin bioassay using dispersed pancreatic acini. A bioassay using dispersed pancreatic acini was used to measure fasting plasma cholecystokinin (CCK) concentrations in 105 patients with various kinds of gastrointestinal diseases, 17 patients with diabetes mellitus, and 6 healthy volunteers. High plasma CCK bioactivities were observed in patients with obstructive jaundice, choledocolithiasis, and primary biliary cirrhosis. Twenty-three samples with high CCK bioactivities were assayed by the same bioassay after the addition of a specific CCK antagonist and by a CCK radioimmunoassay in order to determine whether the high CCK-like bioactivity was due to circulating CCK or other factors. High CCK bioactivities were partially inhibited by the specific CCK antagonist, CR-1409, but the activities were not totally abolished. The residual bioactivities (not inhibited by CR-1409) correlated with plasma bile acid concentrations. The inhibitable CCK bioactivities correlated with plasma CCK levels obtained by radioimmunoassay. Although the bioassay using dispersed pancreatic acini has several advantages for measuring plasma CCK, this method overestimates CCK bioactivities in patients with high plasma bile acid concentrations.
Combination hormonal therapy with tamoxifen plus fluoxymesterone versus tamoxifen alone in postmenopausal women with metastatic breast cancer. An updated analysis. A randomized trial was performed to determine if therapy with tamoxifen (TAM) plus fluoxymesterone (FLU) was more efficacious than TAM alone for postmenopausal women with metastatic breast cancer. Patients failing TAM could subsequently receive FLU. The dose of both drugs was 10 mg orally twice daily. Objective responses were seen in 50 of 119 (42%) TAM patients and 64 of 119 (54%) TAM plus FLU patients (two-sided P = 0.07). Time to disease progression was better for TAM plus FLU (medians: 11.6 versus 6.5 months; Cox model, P = 0.03). Duration of response and survival were similar in the two treatment arms. Among 97 patients with estrogen receptor (ER) of 10 or greater and 65 years of age or older, there were highly significant advantages for treatment with TAM plus FLU in both response rate and time to progression. Of particular note is that in this patient group TAM plus FLU showed a survival advantage (Cox model, P = 0.05). Although these data require confirmation in a prospective randomized trial, they suggest that there is a substantive therapeutic advantage for TAM plus FLU over TAM alone in elderly women with ER of 10 fmol or greater.
A new bioprosthetic cardiac valve with reduced calcification. A bioprosthetic cardiac valve cross-linked with a glycerol polyglycidyl ether polyepoxy compound (PC) was developed in order to reduce calcification and degeneration, which often occurs in bioprosthetic cardiac valves. Aortic valves harvested from dogs were treated with PC (PC valve). Right ventricle (RV)-pulmonary artery (PA) bypasses were placed in 12 dogs with PC-valved conduits, and the main PA was ligated. X-ray right ventriculography at 36 days (1 dog) and 37 days (1 dog) revealed an excellent open/close performance of the PC valve, and there was no visible thrombus in the valve. In our basic study, PC treated collagen gel disks implanted in the subcutaneous layer of growing rats showed remarkably less calcium deposition than did those treated with glutaraldehyde (GA). Biologic materials cross-linked with PC maintain their pliability, and become more hydrophilic and more hydrated than those cross-linked with GA. The hydrophilicity and hydration provide sufficient antithrombogenicity and a suitable environment for metabolism in the tissue fluid which contains oxygen, nutritive substances, and electrolytes, leading to inhibition of material degeneration. Therefore, PC valves are expected to show good valve function, sufficient antithrombogenicity, and excellent durability with less calcification, when compared to GA treated valves.
Intraspinal transplants. Transplants of embryonic central nervous system tissue have long been used to study axon growth during development and regeneration, and more recently to promote recovery in models of human diseases. Transplants of embryonic substantia nigra correct some of the deficits found in experimental Parkinson's disease, for example, by mechanisms that are thought to include release of neurotransmitter and reinnervation of host targets, as well as by stimulating growth of host axons. Similar mechanisms appear to allow intraspinal transplants of embryonic brainstem to reverse locomotor and autonomic deficits due to experimental spinal cord injuries. Embryonic spinal cord transplants offer an additional strategy for correcting the deficits of spinal cord injury because, by replacing damaged populations of neurons, they may mediate the restoration of connections between host neurons. We have found that spinal cord transplants permit regrowth of adult host axons resulting in reconstitution of synaptic complexes within the transplant that in many respects resemble normal synapses. Transplants of fetal spinal cord may also contribute to behavioral recovery by rescuing axotomized host neurons that otherwise would have died. Electrophysiological and behavioral investigations of functional recovery after intraspinal transplantation are preliminary, and the role of transplants in the treatment of human spinal cord injury is uncertain. Transplants are contributing to our understanding of the mechanisms of recovery, however, and are likely to play a role in the development of rational treatments.
Snoring (I). Daytime sleepiness in regular heavy snorers. Fifteen men, mean (means) age 44 years, were investigated. Their means body mass index was 21.9 kg/m2, and all of them had a respiratory disturbance index below 5 and had good nocturnal oxygen saturation. The subjects were monitored several nights both with and without the following devices: a tight-fitting facial mask, a pneumotachometer, and an esophageal balloon. They were also monitored with and without nasal continuous positive airway pressure. The Multiple Sleep Latency Test was administered after three of the experimental nights (after the baseline nights and after the second nasal CPAP night). Determination of short EEG arousals during nocturnal sleep, which lasted 2 to 10 s, was performed. The relationship between short EEG arousals, the esophageal pressure nadir, and airflow decrease was investigated. We also determined the relationship between clinical reporting of decrease in daytime alertness and MSLT results, and the relationship between MSLT results and the frequency of EEG arousals. The monitoring indicated that heavy snorers may present significant increase in Pes nadir with abrupt decrease in flow leading to EEG arousals. The frequency at which EEG arousals occur has an impact on MSLT scores. Nasal CPAP improves MSLT scores and eliminates these respiration-related EEG arousals. Some heavy snorers without obstructive sleep apnea syndrome may be at risk of having a decrease in daytime alertness.
Prospective, randomized trial of the biofragmentable anastomosis ring. The BAR Investigational Group. A randomized trial was undertaken to compare the biofragmental anastomotic ring (BAR) with conventional intraperitoneal colorectal anastomotic techniques. Patients were randomized into one of two schemes: BAR versus sutured or BAR versus stapled anastomosis. There were 782 patients entered into the study and 283 patients (36%) had a sutured anastomosis, 104 patients (13%) had a stapled anastomosis, and 395 (51%) had the BAR. Comparison of the BAR with combined suture and stapled controls revealed no significant differences in wound complication, abscess rate, bleeding, anastomotic leaks, ileus, obstruction, or deaths. There were no differences in return of bowel function, return to normal diet, or hospital stay. Intraoperative difficulties occurred in 46 BAR patients (17%), and this was significantly higher (p less than 0.001) than for sutured (3%) but not for stapled anastomoses (11%). The occurrence of these problems did not adversely effect the outcome. The data suggest that the BAR is a safe, satisfactory alternative to sutured or stapled colorectal anastomoses.
Motor unit discharge characteristics and short term synchrony in paraplegic humans. Frequency of firing and regularity of discharge of human motor units, and short term synchrony between pairs of motor units, have been assessed in extensor digitorum communis (EDC) and tibialis anterior (TA) muscles in control subjects and in clinically complete paraplegic subjects. The discharge pattern of TA motor units in paraplegia ranged from extremely regular to very irregular for different motor units whereas in the control population, and in EDC of both groups, there was a narrow, but intermediate, range of regularity. There was little difference in the incidence and degree of short term synchrony (STS) in EDC between paraplegic and normal subjects. In contrast, virtually no STS of motor units was observed in the TA muscles of the paraplegic group whereas control subjects exhibited approximately the same amount of STS in their TA and EDC muscles. It is concluded that the extra burden placed on arm muscles in paraplegia does not change the amount of synchronisation between motor units. Furthermore, section of the spinal cord does not increase STS as predicted from lesions of the reticulospinal tract in cats. This may reflect the coincidental removal of supraspinal synchronising inputs of motoneurons or the reorganisation of synaptic inputs in chronic paraplegia.
Doppler color-flow images from a stenosed arterial model: interpretation of flow patterns. The capability of the recently introduced Doppler color-flow mapping devices to accurately detect flow patterns in the region of an arterial stenosis was evaluated by use of an in vitro flow model. Pulsatile flow simulating that in a low-resistance vessel was induced through a straight acrylic tube, which alternatively contained axisymmetric stenoses of 0%, 20%, 40%, 60%, and 80% diameter reduction. Doppler color-flow mapper images were taken in realtime along the tube midplane from 0 to 8 diameters downstream of each stenosis. Comparison of the Doppler color-flow mapping results with similarly recorded flow visualization (hydrogen bubble) images showed a close correspondence of key features of the flow, including detection of a high-velocity, centerline jet and near-wall separated flow zones. Distinctive flow patterns exist with each stenotic case, and these should be of considerable value in diagnosing clinical disease conditions.
Salicylate poisoning from enteric-coated aspirin. Delayed absorption may complicate management. Acute salicylate poisoning with enteric-coated aspirin may result from accidental ingestion, a suicide attempt, or a complication of long-term therapy. Because absorption of enteric-coated aspirin is delayed, use of the Done nomogram to determine toxicity may lead to underestimating the severity of the poisoning. Treatment options include induction of emesis or diuresis, gastric lavage, administration of activated charcoal, and surgery.
The course of the HIV epidemic among intravenous drug users in Amsterdam, The Netherlands. To determine if behavioral changes in intravenous drug users in Amsterdam have retarded the HIV (human immunodeficiency virus) epidemic in this group in recent years, we report that: HIV-antibody seroprevalence in annual samples of injectors has been constant over the years 1986-89; HIV-antibody incidence in a cohort of injectors appears to have decreased from 1986 to 1987 and stabilized after that until 1989; acute hepatitis B incidence in all drug users in Amsterdam declined rapidly between 1985-89. It is concluded that changes in drug use behavior so far appear to have resulted in a stabilization of the epidemic among injectors, at a level with a still disturbingly high incidence rate of 5-6 per 100 person-years.
Racial differences in cerebrovascular disease hospitalizations. We studied the relationship of race to incidence of hospitalization for cerebrovascular disease among 74,096 white and 33,041 black persons who took health examinations in a prepaid health care program. Analyses were controlled for age, sex, body mass index, coffee use, smoking, alcohol use, systolic blood pressure, and baseline disease. Blacks were at higher hospitalization risk than whites for hemorrhagic cerebrovascular disease (relative risk = 2.4, 95% confidence interval = 1.3-5.8), cerebral thrombosis (relative risk = 1.9, 95% confidence interval = 1.2-2.9), and nonspecific cerebrovascular disease (relative risk = 1.6, 95% confidence interval = 1.2-2.2) but at lower hospitalization risk for extracranial occlusive disease (relative risk = 0.4, 95% confidence interval = 0.2-0.7). Blood pressure had a similar relation to all types of cerebrovascular disease in both races, but there were disparities in the relations of other atherosclerosis risk factors to different types of cerebrovascular disease. Educational attainment had little relation to hospitalization for extracranial occlusive disease, a finding that reduces the likelihood that selection bias explains the racial disparity. These data show unexplained racial differences in the type and location of cerebrovascular disease. The differences are important in understanding the pathogenesis of cerebrovascular disease and have practical clinical implications.