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31.
We report on the effect of age and chronic caloric restriction (CR) on insulin binding and glucose transporter content in both diaphragm and heart muscle membrane of young (11 months), mid-age (17 months), and old (29 month) ad libitum fed and CR Brown-Norway rats. The control animals received rat chow ad lib and CR animals were allowed 60% of ad libitum food. The CR regimen was initiated at four months of age and the animals were maintained on their respective diets until necropsy. There was no effect of age on insulin binding for either ad libitum or CR animals at each age evaluated. Caloric restriction significantly lowered insulin levels at each age studied when compared to the ad libitum-fed rats. However, CR animals were noted to have increased insulin binding (p < 0.001) compared to ad libitum-fed animals at each age for diaphragm muscle. For the heart, there appeared to be a decreased binding, particularly at higher insulin concentrations, in CR-fed animals. There was no net change in Glut-1 or Glut-4 levels for heart muscle membrane, or Glut-4 levels for diaphragm muscle membrane between ad libitum or CR animals. This data indicates that caloric restriction may have tissue-specific effects for insulin receptor binding, and that the improved insulin sensitivity in CR states is not a result of altered glucose transporter protein content.  相似文献   
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In dry etching processes--one of the sources of potential exposure to toxic wastes in the semiconductor industry--complex mixtures of inorganic and organic compounds arise from reactions between feed stock gases (BCl3/Cl2), top layers (aluminium photoresist), and the carrier gas (N2). Two different fractions of the complex mixture--one an ethanolic solution (ES) and the other an insoluble liquid residue (LR)--were examined for acute oral toxicity in rats. Analytical data showed that the ethanol soluble fraction contained mainly inorganic compounds, whereas the residue contained various halogenated hydrocarbons. Neither death nor behavioral changes occurred after oral administration and observation up to 23 days. ES caused a lower mean arterial blood pressure in both sexes, increased P-R-intervals in male rats, and caused some mild biochemical and hematological alterations and changes in relative organ weights compared to the control groups. Exposure to LR influenced food and water intake, and caused a significant decrease in body weights, signs of polyurie, as well as changes in various relative organ weights and biochemical and hematological parameters. The blood pressure of the male animals fell and the heart rates of both sexes decreased.  相似文献   
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Summary Three patients who presented with long-standing medial knee pain and normal radiographs had an isotope bone scan in an attempt to arrive at a diagnosis. In each case there was a well-defined area of increased uptake over the medial tibial condyle and arthroscopy subsequently revealed meniscal damage. After arthroscopic menisectomy each patient became asymptomatic and the bone scan returned to normal. We suggest that patients with incapacitating knee pain, normal radiographs and a positive bone scan undergo an arthroscopy even in the absence of clinical signs of meniscal damage.
Résumé Trois malades qui présentaient depuis longtemps des douleurs de la partie interne du genou et dont les radiographies étaient normales ont bénéficié d'une scintigraphie afin d'essayer d'ðablir un diagnostic. Dans tous les cas il y avait une zone bien limitée d'hyperfixation au niveau de la partie interne de l'extrémité supérieure du tibia, et l'arthroscopie ultérieure découvrit une lésion méniscale. Après méniscectomie arthroscopique tous les malades furent soulagés et la scintigraphie redevint normale. Nous proposons que l'on pratique une arthroscopie, même en l'absence de signes cliniques d'atteinte méniscale, chez les sujets présentant des douleurs notables du genou, avec des radiographies normales et une scintigraphie positive.
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实验性单纯疱疹性角膜炎的组织病理学研究   总被引:1,自引:0,他引:1  
目的:动态观察1型单纯疱疹病毒(HSV-1)感染角膜后的组织病理改变。方法:BALB/c小鼠眼角膜接种HSV-1(KOS株)以诱发单纯疱疹性角膜炎(HSK)。分别收集正常眼球及感染后第2、7、14天的感染眼球,组织学观察结膜及角膜的病理过程。结果:感染后第2天,中性粒细胞、淋巴细胞及其他单核细胞浸润结膜并在第7-14天间快速向中央角膜扩散。结论:在HSK发展中,中性粒细胞浸润导致进行性的组织破坏。  相似文献   
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A total of 178 patients with metastatic renal cell cancer were randomized to receive interferon alfa-2a (rIFN alfa-2a) or interferon alfa-2a+vinblastine (VLB). IFN alfa-2a was injected intramuscularly at a dose of 18 MIU 3 times a week and VLB was given intravenously at a dose of 0.1 mg/kg once every 3 weeks. The response rate was 11% for patients on monotherapy and 24% for those on combination treatment. The 5-year survival for 145 eligible patients was 9%, independently from the treatment arm. The performance status was significantly related to long-term prognosis, and 13% of the patients with performance status 0 were alive at 5 years, as compared to 6% and 0% for patients with a WHO grade of 1 and 2, respectively. The most frequent adverse events in both treatment arms were flu-like symptoms (95%), fatigue (70%) and gastrointestinal disturbances (68%). Leukopenia was observed more frequently with combination treatment (53%) than with IFN alfa-2a alone (30%). In conclusion, rIFN alfa-2a monotherapy at this dose and schedule has modest antitumor activity in metastatic renal cell cancer. The combination of rIFN alfa-2a+VLB results in a doubling of the response rate, but this does not translate into prolonged survival. Toxicity (except leukopenia) and tolerance were similar in both treatment arms.  相似文献   
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