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1.
The rheological characterisation of glucose sensitive mixtures containing dextran and concanavalin A (con A) with and without glucose, was undertaken using oscillatory rheometry at 20 and 37 degrees C so that comparative data could be gathered in the linear viscoelastic (LVE) range. Measurements for a series of mixtures showed that complex viscosity is a function not only of the con A concentration but of the content and molecular weight of the dextran used. The extent of liquefaction on addition of glucose also depended on these factors. The tan delta profiles confirmed the change from semi-solid towards fluid behaviour. This occurs when glucose effects dismantling of the three-dimensional structure of the dextran-con A system by competitive binding to the glucose receptors in the protein. For the mixtures studied, the changes occurred between contents of 0 and 1% (w/w) glucose at 20 and 37 degrees C and form a useful basis for the formulation of a self-regulating delivery device for the control of hyper-and hypoglycaemia in diabetes.  相似文献   
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Alcohol and other drug (AOD) use behaviors of health professions students (HPS) were assessed by surveying both university-based HPS and other nursing programs in a Midwestern state in 1999. Response was 2,646 (56.4%) of surveyed students. Family history of alcohol-related and drug-related problems were reported by 39.8% and 13.9%, respectively, with 42.6% of respondents reporting one or both. Among nursing respondents, 48.1%, 19.2% and 51.1%, respectively, reported family problems with alcohol, drugs, or one or both. Past-year alcohol use was comparable to undergraduate college students (UCS) nationally (83%); heavy drinking, tobacco and recreational drug use by HPS were lower. Past year drug use was highest among medical students. Marijuana was the predominant illicit drug; medical students and males most often reported use. Health professions educational systems should proactively address student AOD prevention, education and assistance needs.  相似文献   
3.
Angiosarcoma is a rare, highly malignant tumor arising from endothelial cells of small blood vessels. They usually occur in the skin, deep soft tissues, breast and liver. Pleural angiosarcomas are extremely rare and are restricted to case reports in medical literature. It is very difficult to distinguish them from malignant mesotheliomas on clinical, radiological and even histopathological features. Immunohistochemistry is valuable in making the diagnosis, showing negative reactivity for mesothelial markers and positivity for vascular markers. Prognosis is generally dismal except in occasional cases where the disease is localized and amenable for surgical resection. We report a 55-year-old man who presented to us with chest pain, cough and hemoptysis and was diagnosed to have a pleural angiosarcoma.  相似文献   
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Twenty-four cases of trichotillomania attending psychiatry outpatient department and child guidance clinic at Kalawati Saran Children's and Smt Sucheta Kriplani Hospitals over a period of 2 years from July, 1985 to November 1987 were studied. Females (66.7%) outnumbered the males (33.3%). Majority of cases belonged to age group 6-10 years (54.2%) and nuclear family (68.5%). Nail-biting (25.0%) was the commonest associated neurotic trait, followed by enuresis (20.9%), temper-tantrum (12.5%), etc. A past history of hysterical fits and neurotic depression was found in 3 cases (12.5%) and 2 cases (8.3%) respectively. Family history of neurosis was seen in mothers and fathers of 20.9% and 12.5% cases respectively. Trichobezoars and trichophytobezoars were found in 6 cases (25.0%) and 3 cases (12.5%) respectively. Majority of patients of trichobezoars presented with vague complaints like heaviness in the stomach (55.6%), inability to gain weight (44.4%), etc, while 22.2% cases were asymptomatic and detected only on screening.  相似文献   
7.
This is a double-blind placebo-controlled study of sustained-release bupropion as a smoking cessation aid in alcoholics undergoing treatment for their alcoholism. Participants (N=58) were enrolled within 1 week of entry into alcohol treatment from community and Veterans Affairs Substance Use Disorder programs. All participants received nicotine patch and were invited to attend a smoking cessation lecture and group. Cigarette smoking and alcohol outcomes were measured at 6 months. Bupropion when added to nicotine patch did not improve smoking outcomes. One third of participants on bupropion reported discontinuing the drug during weeks 1-4. Participants reported cigarette outcomes with nicotine patch that are similar to those seen in the general population. All study participants significantly reduced cigarette use. Comorbid affective disorder or antipersonality disorder did not affect outcomes. Alcohol outcomes were improved in those who discontinued cigarettes.  相似文献   
8.
OBJECTIVE: To identify the incidence of bleeding complications associated with peritoneal dialysis catheter insertion. DESIGN: Retrospective review at a tertiary-care center of all double-cuffed Tenckhoff catheters placed surgically from 1 January 1992 to 1 October 2003 to identify the incidence of major bleeding complications occurring with catheter insertion. Major bleeding episodes were defined as > or = 3% decline in hematocrit, or the need for surgical intervention or blood transfusion within 2 weeks of insertion. RESULTS: 292 catheters had been inserted in 263 patients. Six patients satisfied the criteria for a major bleeding event, for a major bleeding complication rate of 2%. Bleeding was associated with perioperative anticoagulation in 3 patients, uremia and thrombocytopenia in 1 patient, aspirin use and thrombocytopenia in 1 patient, and 1 patient experienced intraoperative bleeding. Coagulation parameters were not obtained prior to the procedure in 2 of the 6 patients. CONCLUSION: The rate of serious bleeding complications related to catheter insertion is low and usually associated with anticoagulation. Holding anticoagulation therapy for a minimum of 24 hours during the postoperative period should eliminate much of the risk. Coagulation parameters should also be obtained and corrected preoperatively.  相似文献   
9.
A 50-year old male presented with swollen right eyelids, bleeding per nostrils and a vague left post-auricular swelling for 4 months. Posterior rhinoscopy revealed one pinkish polypoidal mass in the posterior nare and roof of nasopharynx. FNAC from the post-auricular swelling suggested metastatic undifferentiated carcinoma. Incisional biopsy was done form the nasopharynx and histopathological examination proved it to be a malignant paraganglioma. The case is reported for its rarity.  相似文献   
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