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91.
Two elderly female patients are described with generalized histiocytosis X (Letterer-Siwe disease). In each case, a definitive diagnosis was not established until ultrastructural and immunoperoxidase investigations had been performed. The histopathological findings in skin biopsies from each patient were similar. Light microscopy demonstrated a bandlike epidermotrophic cellular infiltrate which included large atypical cells (histiocytosis X cells). Electron microscopy showed that these cells contained Birbeck granules. Monoclonal antibody studies demonstrated the presence of T6, T4 and HLA-DR surface antigens. Lysozyme and alpha-I-antitrypsin were absent from the cells. The associated cellular infiltrate included T4 and T8 positive lymphocytes. It is possible that more cases of generalized histiocytosis X in adults will be identified with the increasing use of specialized histopathological techniques and that the disease is more common than currently believed.  相似文献   
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94.
The study of membrane fluidity is a rapidly expanding field of research and its interest in hepatology has been stressed recently. The present study is the first report concerned with the determination of membrane fluidity of isolated rat hepatocytes. The data have been compared with those obtained in plasma membrane fractions and subfractions (basolateral or canalicular) derived from homogenates. The fluorescent probes used to measure the fluidity were diphenylhexatriene (DPH) a 'classical' probe, and its derivative trimethylammoniodiphenylhexatriene (TMA-DPH) at 25 degrees C and at 37 degrees C. The values obtained with DPH were lower than those with TMA-DPH, probably due to the localization of the probes in different regions of the phospholipid bilayer. In addition, DPH revealed significant differences in the fluorescence polarization values obtained in isolated hepatocytes compared with membrane fractions, which was in contrast to TMA-DPH, where the respective values were of the same order of magnitude. This behaviour is probably due to the mobility of DPH in the membrane core and its rapid internalization into the cell, whereas TMA-DPH remains anchored for a long time on the cell surface. These findings suggest that TMA-DPH is a better probe than DPH for measuring the fluorescence polarization of whole isolated hepatocytes and that the use of different probes might be of help in exploring different zones of the membrane bilayer.  相似文献   
95.
In a cohort study of 1080 pupils who were followed for 5 years from when they left compulsory school (from age 16 to age 21 years), smoking habits were found to correlate with unemployment among both boys and girls. Pupils who zuere smokers in school had a higher risk of becoming unemployed than non-smokers. Irrespective of early smoking, smoking habits developed more unfavourably among unemployed young people than among those with no unemployment during the period studied. The odds ratio of being a smoker at the age of 21 years when unemployed more than 20 weeks during the observation period, compared with those without or with short unemployment, was 2.44 for men and 3.45 for women. When adjusted for the influence of socio-economic background, education, economy and smoking habits at the start of the period, the odds ratio was 1.7 (95% CI 1.01 2.86) for men and 2.0 (1.13–3.53) for women. The adjusted odds ratio for increasing or starting smoking during the period was 1.5 (95% CI 0.89-2.56) for men and 2.0 (1.18–3.35) for women. No significant correlation was found between snuffing and unemployment. Thus, it seems that unemployment is a risk factor for development of tobacco smoking in young people, especially among women.  相似文献   
96.
Gastric and oesophageal emptying in insulin-dependent diabetes mellitus   总被引:4,自引:0,他引:4  
Abstract Gastric emptying of a digestible solid and liquid meal and oesophageal emptying of a solid bolus were measured with scintigraphic techniques in 45 randomly selected insulin-dependent diabetics and in 22 control subjects. In the diabetics, the relationships between oesophageal emptying, gastric emptying, age, duration of diabetes mellitus, upper gastrointestinal symptoms, glycaemic control and the complications, autonomic neuropathy, peripheral neuropathy and retinopathy were examined. The lag period before solid food left the stomach was not significantly different in diabetics compared with control subjects, but the percentage retention of solid food at 100 min was greater ( P < 0.001) in the diabetic subjects. Both the early phase (percentage retention at 10 min) and the 50% emptying time for liquid gastric emptying were delayed ( P < 0.001) in the diabetic subjects. Of the diabetics, 58% had delayed gastric emptying of either the solid and/or the liquid meal; oesophageal emptying was delayed in 42%. Upper gastrointestinal symptoms correlated poorly with both gastric and oesophageal emptying. Oesophageal emptying, solid gastric emptying and the liquid 50% emptying time correlated with the severity of autonomic nerve dysfunction ( P < 0.05). The early phase of liquid emptying (retention at 10 min) was significantly slower ( P < 0.05) in patients with mean plasma glucose concentrations of > 15 mmol/l during the gastric emptying test and the lag period for solid emptying correlated with both the glycosylated haemoglobin and mean plasma glucose concentrations.  相似文献   
97.
The effects of concurrent graft-versus-host reaction (GvHR) on the course of Giardia infection in CBA x BALB/c F1 mice have been examined, to test the hypothesis that T-cell-mediated immunity, in the form of a local DTH reaction, alters the host-parasite relationship in favour of the host by changing the physical environment of the parasite. GvHR did not enhance immunity, indeed mice infected with Giardia at a late stage of GvHR had significantly higher faecal cyst excretion and prolongation of the plateau phase of infection, indicating a degree of immunodeficiency.  相似文献   
98.

Purpose

We developed an algorithm using unenhanced computerized tomography (CT) for the management of acute flank pain and suspected ureteral obstruction.

Materials and Methods

During a 25-month interval 417 patients with acute flank pain underwent unenhanced helical CT. The final diagnosis was confirmed by additional imaging or clinical followup. For all patients who underwent additional imaging studies the official dictated radiology reports were used to determine whether the studies were recommended based on CT findings. Cases requiring intervention were evaluated to determine whether additional imaging was performed before the procedure. Medical records were reviewed and/or patients were interviewed to document the course of therapy and long-term outcome.

Results

Unenhanced helical CT diagnosed ureteral stone disease with 95% sensitivity, 98% specificity and 97% accuracy. Of the 38 patients requiring intervention, including nephrostomy catheters in 18, lithotripsy in 3 and ureteroscopic stone extraction in 7, additional imaging (excretory urography) was performed in only 1. Additional imaging studies generated by CT were done in 3 cases in which the dictated reports were indeterminate for ureteral stones, including negative excretory urography in 2 and retrograde urography in 1. In 1 patient in whom CT misdiagnosed a ureteral stone unnecessary retrograde urography revealed the calcification to be a gonadal vein phlebolith. Seven patients with false-negative examinations reported spontaneous stone passage with no complications.

Conclusions

Unenhanced helical CT accurately determines the presence or absence of ureterolithiasis in patients with acute flank pain. CT precisely identifies stone size and location. When ureterolithiasis is absent, other causes of acute flank pain can be identified. In most cases additional imaging is not required.  相似文献   
99.
术后疼痛护理中的障碍分析及对策   总被引:1,自引:0,他引:1  
疼痛是医务人员在临床工作中 ,尤其是外科术后经常面临的一个问题。据报道大于 50 %的术后病人在常规医嘱度冷丁、肌注、PRN的情况下仍报告疼痛不能缓解[1] ,因此疼痛普遍存在 ,疼痛没有及时治疗普遍存在。最近 ,我们以我院术后第 1天病人的疼痛控制情况作了咨询调查 ,发现 50 %以上的病人有术后医嘱度冷丁、肌注、PRN ,仍报告有重度的疼痛 ,导致病人活动、咳嗽、深呼吸障碍 ,而这种情况多数是由于护士没有及时地用止痛药。针对这种状况我们组织护士长、教学护士、护士一起讨论 ,分析原因 ,找出影响术后疼痛护理质量的障碍 ,针对这些…  相似文献   
100.
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