123rc/medical_text huggingface dataset:
Comparison of Delphin and BioMedicus pumps. There is an increasing use of centrifugal pump systems for cardiopulmonary bypass (CPB) and circulatory assistance. The BioMedicus and Delphin centrifugal pump systems were tested in two side-by-side, identical in vitro flow loops for blood trauma and flow probe accuracy. Blood parameters tested were hemoglobin, hematocrit, lactate dehydrogenase, free plasma hemoglobin, and platelet counts. The Delphin pump demonstrated significant increases in plasma hemoglobin levels at the three flow rates tested: 2 L/min (p less than 0.05), 4 L/min (p less than 0.005), and 6 L/min (p less than 0.05). After 4 hr of pumping, the drop in platelet counts was significantly greater in the BioMedicus loop as compared with the Delphin loop (p less than 0.05) at the 2 L/min and 4 L/min flow rates; however, platelet levels remained within normal ranges in both systems. At 6 L/min, no statistical difference in platelet counts was noted. The flow probe readings were found to deviate by as much as 58% of stopwatch timed flow rate comparisons at low flow rates, but improved to within 10% or better at 6 L/min.
Radiographic manifestations of congenital anomalies affecting the airway. Congenital anomalies of the airway are generally uncommon, but a vast array of possibilities exists. Some present life-threatening emergencies at birth, and others go undiagnosed for years. Clinical symptoms are often nonspecific, and radiographic evaluation is frequently requested to localize and characterize the lesion before endoscopy, surgery, or medical management. The most common intrinsic congenital anomalies causing airway compromise in infants include choanal atresia, mandibular hypoplasia, laryngomalacia, vocal cord paralysis, and congenital subglottic stenosis. The radiologist must be on the alert for unsuspected additional anomalies involving the airway, lungs, and esophagus, which occur with relative frequency. Numerous extrinsic congenital masses of the head, neck, and mediastinum may compromise the airway. Hemangiomas, lymphangiomas, and teratomas are more likely to be noted at birth, whereas branchial cleft cysts, thyroglossal duct anomalies, and dermoid cysts frequently present later. Mass location and radiographic characteristics usually allow accurate preoperative diagnosis. Intracranial involvement by nasal or nasopharyngeal masses, intrathoracic involvement by lower neck mass, and intraspinal involvement by posterior neck mass must always be sought for radiographically. Persistence of respiratory symptoms after removal of such masses is not uncommon because tracheal deformity and laxity may take months or years to resolve. Recent advances in cine CT and MR imaging promise to improve imaging of the airway in general and in the pediatric population in particular. Significant limitations in imaging of the pediatric larynx remain. As a result, endoscopy continues to be the primary diagnostic tool for airway anomalies of this region.
Cervical spine stabilization. A three-dimensional, biomechanical evaluation of rotational stability, strength, and failure mechanisms. The three-dimensional rotational biomechanical properties of several different types of posterior stabilizing procedures are reported. A severe ligamentous and bony injury was simulated with three vertebral body human cervical spine segments. Good stabilization was noted for all of the repairs in flexion loading. Without polymethylmethacrylate supplementation, none of the repairs was stable in extension. All of the repairs provided reasonable stabilization for lateral bending except for the posterior wiring without methacrylate, and all but the posterior wiring and facet fusion provided reasonable stabilization against axial rotation loading. The supplementation of all of these repairs with polymethylmethacrylate added considerably to the stability of all the constraints. These findings may be useful in clinical decision-making for determining the kind of repairs and postoperative brace protection to use.
Tumor-secreted vascular permeability factor increases cytosolic Ca2+ and von Willebrand factor release in human endothelial cells. Vascular permeability factor (VPF), a tumor-secreted heparin-binding protein (Mr approximately 38,000), is responsible for increased vessel permeability and fluid accumulation associated with tumor growth. Vascular permeability factor also promotes the growth of human umbilical vein endothelial cells (EC) and bovine pulmonary ECs in vitro. It is shown for the first time that guinea pig VPF (half-maximal and maximal dose approximately 0.4 and 22 pmol/l (picomolar), respectively), as well as human VPF, are potent stimuli for human ECs resulting in [Ca2+]i increases (maximal three- to fourfold) and inositol triphosphate (IP3) formation. Unlike the maximal responses to thrombin and histamine, the [Ca2+]i response to a maximal VPF dose was preceded by a characteristic 10- to 15-second delay. Guinea pig VPF also selectively increased [Ca2+]i in cultured aortic and pulmonary artery ECs, but not aortic smooth muscle cells, human fibroblasts, or neutrophils. Affinity-purified rabbit antibody (raised to a synthetic peptide representing VPF N-terminal amino acids 1 to 24) adsorbed all vessel permeability-increasing activity, EC growth-promoting activity, and specifically all activity responsible for increasing EC [Ca2+]i. Similar to other mediators that increase [Ca2+]i in cultured ECs, VPF also induced a 200% increase in von Willebrand factor release. Together these data indicate that VPF acts directly on ECs and that rapid cellular events in its in vivo/in vitro actions are likely to involve phospholipase C activation, [Ca2+]i increase, and von Willebrand factor release.
Can clinicians accurately assess esophageal dilation without fluoroscopy? This study questioned whether clinicians could determine the success of esophageal dilation accurately without the aid of fluoroscopy. Twenty patients were enrolled with the diagnosis of distal esophageal stenosis, including benign peptic stricture (17), Schatski's ring (2), and squamous cell carcinoma of the esophagus (1). Dilation attempts using only Maloney dilators were monitored fluoroscopically by the principle investigator, the physician and patient being unaware of the findings. Physicians then predicted whether or not their dilations were successful, and they examined various features to determine their usefulness in predicting successful dilation. They were able to predict successful dilation accurately in 97% of the cases studied; however, their predictions of unsuccessful dilation were correct only 60% of the time. Features helpful in predicting passage included easy passage of the dilator (98%) and the patient feeling the dilator in the stomach (95%). Excessive resistance suggesting unsuccessful passage was an unreliable feature and was often due to the dilator curling in the stomach. When Maloney dilators are used to dilate simple distal strictures, if the physician predicts successful passage, he is reliably accurate without the use of fluoroscopy; however, if unsuccessful passage is suspected, fluoroscopy must be used for confirmation.
Multimodality therapy for advanced and recurrent vulvar squamous cell carcinoma. A pilot project. From 1985 to 1989 eight women with advanced or recurrent vulvar carcinoma were treated at the Women's Cancer Center of the University of Minnesota Hospital and Clinic. Each received a combination of 5-fluorouracil, mitomycin C and cisplatin during radiotherapy. Five of the eight women who underwent posttreatment radical vulvectomy had acceptable operative morbidity. Six patients experienced a complete clinical response. Of them, one had microscopic residual disease in the surgical specimen. One patient with recurrent vulvar carcinoma experienced progression of disease on therapy. One death was attributable to chemotherapy toxicity, and two patients died of intercurrent disease. The overall survival rate at 27 months was 33%. This multimodality approach to the treatment of advanced vulvar carcinoma should be considered when designing a therapeutic approach to treating extensive or resistant vulvar carcinoma.
Continuous arteriovenous rewarming: experimental results and thermodynamic model simulation of treatment for hypothermia. We evaluated a technique for treating hypothermia that uses extracorporeal circulation but does not require heparin or pump assistance. Hypothermia to 29.5 degrees C was induced in eight anesthetized dogs, and thermistors placed in the pulmonary artery, liver, bladder, esophagus, rectum, muscle, and skin. Four experimental animals were rewarmed by creating a fistula which connected arterial and venous femoral lines to an interposed counter-current heat exchanger. External rewarming was used in four controls. Bleeding time (BT), coagulation profile (PT, PTT, TT), and cardiac output (CO) were measured during rewarming. Core temperature (T) rose significantly faster with CAVR (0.00001). Average time to rewarming was 45 min, vs. 4 hrs in controls. Haptoglobin, platelet, fibrinogen, and fibrin split product levels were unaffected. Continuous arteriovenous rewarming (CAVR) improved T, CO, BT, and coagulation profile faster than any method yet reported not requiring heparin or cardiac bypass. The application of CAVR in post-traumatic hypothermia warrants further investigation.
Immunodetection of the metastasis-associated laminin receptor in human breast cancer cells obtained by fine-needle aspiration biopsy. Fine-needle aspiration biopsy of the breast is a very useful technique for the evaluation of a suspect lesion before surgical removal. Increased expression of the 67-kd laminin receptor has been associated with the metastatic phenotype of cancer cells, particularly in colon and breast cancers. In this study, the expression of laminin receptor was evaluated using the immunoperoxidase technique in 81 breast aspirates (26 benign and 55 neoplastic lesions). Cells obtained from benign samples exhibited a low level of laminin receptor antigen detected by affinity-purified antibody raised against a cDNA-derived laminin receptor peptide. In contrast, 71% of smears obtained from malignant breast lesions contained cells that were strongly stained by the antibody. Heterogeneous expression of the laminin receptor was noted in both breast aspirates and fixed tissue specimens. These data suggest that the immunodetection of laminin receptor in cells obtained by fine-needle aspiration of breast lesions could be a valuable adjunct in the prognostic evaluation of breast lesions.
Postoperative hypoxemia after nonabdominal surgery: a frequent event not caused by nitrous oxide. We tested whether anesthesia that includes nitrous oxide (N2O) results in the development of intraoperative and postoperative pulmonary complications, including hypoxemia. We also tested whether aging contributes to the development of such complications, particularly when anesthesia includes N2O. We randomly allocated patients having total hip replacements, carotid endarterectomies, or transsphenoidal hypophysectomies (total n = 270) to an anesthetic regimen with and without N2O (stratified within surgical group). A heat-and-moisture exchanger was included in the anesthetic circuit of all patients. Patients were monitored perioperatively and for 1 wk after surgery using intermittent and continuous pulse oximetry to determine oxyhemoglobin saturation. Intraoperatively, mean oxygen (O2) saturations were lower in patients given N2O, particularly older patients. Hypoxemia (O2 saturation less than 86%) developed in five patients receiving N2O and in one receiving O2. This difference was not significant. Administration of N2O did not decrease postoperative O2 saturation, nor did it alter the incidence of postoperative hypoxemia, cough, or sputum production.
Neurofibromatosis type 2: report of a family and review of current evaluation and treatment. Significant advances during the past decade have greatly improved our understanding of neurofibromatosis type 2, a genetic disease which results in bilateral acoustic neuromas. The emergence of gadolinium-enhanced magnetic resonance imaging has allowed early detection of minute intracanalicular eighth-nerve tumors, less than 1 cm in diameter. Recombinant DNA studies have clarified the genetics that underlie neurofibromatosis type 2 and separate it from a variety of related conditions, such as von Recklinghausen's neurofibromatosis. Early diagnosis and surgical removal of these tumors may offer the only hope of preserving hearing and facial nerve function. A report of the evaluation and treatment of a family with multiple affected individuals will exemplify these conclusions.
A syndrome characterized by nodular eosinophilic infiltration of the skin and immunoglobulin isotype imbalance. A 9-year-old boy had recurrent acute, plaquelike, nodular infiltrations with overlying vesicles and bullae of the face and right hand. Histologically, the lesions consisted of a perivascular and periadnexal lymphohistiocytic infiltrate with many eosinophils. The lesions responded to dapsone therapy. Laboratory studies revealed blood eosinophilia, hyperimmunoglobulinemias E and G4, and hypoimmunoglobulinemias M and G1-3, which normalized after treatment. The patient's immune deviation is consistent with a transient imbalance of lymphokine production in helper T cells.
ECMO assisted angioplasty for cardiomyopathy patients with unstable angina. Patients who are otherwise unsuitable candidates for coronary bypass surgery or standard coronary angioplasty (PTCA) may be successfully treated with PTCA during ECMO. Five patients (3 men, 2 women), with a mean age of 57 years, are reported on here. They were not considered good candidates for standard therapy because of poor left ventricular function (mean EF, 24; range, 16 to 28%). Patients were supported by percutaneous femoral bypass using a BARD CPS machine, and underwent successful PTCA of either two vessels (three patients) or three vessels (two patients); in addition, one patient had dilatation of a stenotic aortic valve. Patients were supported with ECMO for 26 to 140 (mean 104) minutes, and required transfusion with 0 to 4 (mean 2) units of blood during or after the procedure. Complications included groin hematoma in two patients. All were discharged within 4 days of the procedure. Follow-up of the patients has been completed (4-7 mo) with no further hospitalizations for unstable angina. All patients remain in NYHA Class II or III. These data suggest that ECMO-assisted angioplasty is a safe and effective method of palliation of unstable angina associated with cardiomyopathy.
Radionuclide imaging in otolaryngology-head and neck surgery. Radionuclide imaging provides both qualitative and quantitative information that can have dramatic effects on patient management in diseases of the head and neck. The general concepts of nuclear medicine imaging, including radiopharmaceuticals and radiation effects, are discussed. The principles and techniques of thyroid, parathyroid, bone, and salivary radionuclide imaging studies will be reviewed. The intent of this article is to provide a concise and current review of head and neck radionuclide imaging that will be useful in the day-to-day practice of otolaryngology-head and neck surgery.
Intraoperative pathologic diagnosis of thyroid neoplasms. Report on experience with 504 specimens. Intraoperative pathologic examination with frozen section (FS) was performed on 504 specimens of thyroid tissue obtained from 457 patients over a period of 9 years. After examination of permanent sections (PS) a malignant neoplasm was diagnosed in 57 specimens (11.3%); 50 (87%) of these were primary thyroid carcinoma, four (8%) metastatic carcinoma, and three (5%) malignant lymphoma. The FS diagnosis was "benign" in 448 (88.9%), "malignant" in (30) 5.9%, and "deferred" in 26 (5.2%). The sensitivity of FS diagnosis of malignancy was 53% and the specificity and positive predictive value 100%. The negative predictive value was 97.8% and overall accuracy 97.9%. The PS disclosed a malignant neoplasm in 62% of specimens in which FS diagnosis was "deferred." Sixty-eight percent of papillary carcinomas, 87% of undifferentiated carcinomas, and a single case of medullary carcinoma were diagnosed with FS examination. A FS diagnosis of malignancy was not made in any of the ten specimens containing follicular carcinoma; in all ten the neoplasms were well-differentiated and eight were encapsulated and minimally invasive. The inability to diagnose follicular carcinoma intraoperatively with FS is the most significant factor accounting for the relatively low sensitivity of FS diagnosis of malignant thyroid neoplasms.
Delayed facial palsy following uncomplicated stapedectomy. We report six cases of partial lower motor neurone facial palsy occurring between four and ten days after uncomplicated stapedectomy. The aetiology is unclear but recovery was rapid and complete in all patients.
Child care practices with respect to acute respiratory tract infection in a poor, urban community in Nigeria. A longitudinal study conducted over a 3-year period in a poor, urban community in Nigeria, a developing country, found that acute respiratory tract infection (ARI) was common, in particular among infants and boys. Between 81% and 95% of the children treated for ARI over the 3-year period were brought to the clinic by their mothers. About 32% of these children had been treated with cough medicines, 42% with antipyretics, 5% with antibiotics, and 10% with hematinics before they were brought to the clinic. The source of such medications included medicines left over from previous prescriptions and those bought from chemists' shops and street vendors. Up to 64% of the children treated for ARI had been force-fed local herbal teas by their mothers; herbal teas were used for both preventive and curative purposes.
Levamisole and 5-fluorouracil therapy for resected colon cancer: a new indication. OBJECTIVE: To evaluate the benefits and risks of postoperative treatment with levamisole plus 5-fluorouracil (5-FU) in patients with colon cancer. DESIGN: Computerized searches of MEDLINE and CANCERLIT were performed, and the reference list of each retrieved article was checked. Only randomized trials of therapy with levamisole alone or combined with 5-FU for colon cancer without distant metastases were included. The studies were then evaluated with the use of four criteria. RESULTS: We reviewed six randomized trials, of which three satisfied our criteria. Two studies demonstrated a significant improvement in the survival rate with levamisole plus 5-FU among patients with colon cancer and pathologically confirmed metastases to adjacent lymph nodes (Dukes' stage C). A subgroup analysis in another study demonstrated a similar benefit. The toxic effects of the drugs were generally mild. The three other studies showed no difference in survival rates between the treatment groups; however, the samples were too small to detect a clinically or statistically important difference. CONCLUSIONS: Because many patients with colon cancer will suffer a relapse we recommend that they be offered the opportunity to participate in clinical trials of adjuvant therapy. For those with stage C disease not entering a clinical trial levamisole plus 5-FU is appropriate adjuvant therapy.
Acute aluminum toxicity after continuous intravesical alum irrigation for hemorrhagic cystitis. An encephalopathy and cardiomyopathy developed in a seventeen-year-old girl with chemotherapy-induced renal failure while receiving an intravesical aluminum infusion for hemorrhagic cystitis. Premortem serum and postmortem tissue aluminum levels were markedly elevated. It is likely that her inability to excrete absorbed aluminum contributed to her death. Aluminum infusions should be used with caution in patients with renal failure.
Diagnosis and management of familial dyslipoproteinemia in children and adolescents. CAD results from atherosclerosis, a chronic disease process that has its origin in childhood. Children and adolescents can be at higher risk for CAD by virtue of being from families with premature CAD or familial dyslipoproteinemias. The plasma lipid and lipoprotein levels result from a number of complex metabolic processes that are under the control of genetic and environmental (e.g., diet) influences. The normal ranges of plasma lipids and lipoproteins in children are known, and children and adolescents with dyslipoproteinemia are ordinarily defined as those having levels of plasma total, LDL, or triglyceride above the 95th percentile or with a low HDL cholesterol below the 5th percentile. Children of a parent with documented dyslipoproteinemia or with family history of premature CAD may be screened in the fasting state any time after 2 years of age. Following the exclusion of secondary causes of dyslipoproteinemia, the diagnosis of primary dyslipoproteinemia can be made. Lipoprotein patterns are not diagnostic for a given genotype. Efforts to determine further the biochemical defects responsible for a given phenotype have led to the investigation of gene coding for the apolipoproteins, the key enzymes in the lipoproteins pathways (LPL, HDL, and LCAT) and the receptors that process lipoproteins, such as the LDL receptor and the chylomicron remnant receptor. From a practical standpoint, the diagnosis of the kind of dyslipoproteinemia in a child will depend upon the nature and severity of the dyslipoproteinemia, both in the child (or adolescent) and in parents and siblings. Marked increases in plasma total and LDL cholesterol in the child and in at least one of the parents often reflect the presence of familial hypercholesterolemia, an inherited dominant condition due to a defect in the LDL receptor gene. The triglyceride levels are often normal. If the child has a different dyslipoproteinemia pattern from siblings and parents, then the diagnosis of familial combined hyperlipidemia or hyperapobetalipoproteinemia should be considered. Most children with mild or borderline elevations in total and LDL cholesterol will have polygenic hypercholesterolemia. Triglyceride problems in children and adolescents are relatively uncommon, particularly the more severe hypertriglyceridemia such as that found in lipoprotein lipase and apoC-II deficiency, dysbetalipoproteinemia, and type V hyperlipoproteinemia. High levels of Lp(a) lipoprotein, in isolation or in combination with other dyslipoproteinemia, accelerate risk for CAD. Low levels of HDL cholesterol in the absence of other abnormalities suggest the diagnosis of hypoalphalipoproteinemia.(ABSTRACT TRUNCATED AT 400 WORDS).
Immunodominant regions for T helper-cell sensitization on the human nicotinic receptor alpha subunit in myasthenia gravis. In myasthenia gravis an autoimmune response against the nicotinic acetylcholine receptor (AChR) occurs. The alpha subunit of the AChR contains both the epitope(s) that dominates the antibody response (main immunogenic region) and epitopes involved in T helper cell sensitization. In this study, overlapping synthetic peptides corresponding to the complete AChR alpha-subunit sequence were used to propagate polyclonal AChR-specific T helper cell lines from four myasthenic patients of different HLA types. Response of the T helper lines to the individual peptides was studied. Four immunodominant sequence segments were identified--i.e., residues 48-67, 101-120, 304-322, and 419-437. These regions did not include residues known to form the main immunogenic region or the cholinergic binding site, and they frequently contained sequence motifs that have been proposed to be related to T-epitope formation.