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61.
62.
Narcotisized dogs were artificially ventilated for periods of two to five hours with HFPPV. During this time the blood gases, pH and bases were controlled. In spite of sufficient oxygenation and CO2-elimination, a metabolic acidosis developed which could not be fully compensated by the addition of buffer solutions. In light and electron microscopy these lungs did not differ significantly from control lungs. Haemorrhages or atelectases were never observed. Type I cells as well as Type II cells in the alveoli are unchanged, i.e. the Type II cells were not depleted but contained numerous typical lamellar bodies with a diameter of 0.4-1 mu. The blood gas barrier was not widened and was ca. 3000 A wide. The alveolar surface was coated by an often fragmented electron-dense film (monolayer of the surfactant).  相似文献   
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Specificity of natural cell-mediated cytotoxicity was investigated through selective reactions detected by direct cell-mediated cytotoxicity and by inhibition of cytotoxicity through competition. Assuming that target cells reacting alike in direct cytotoxicity shared common antigens, we classified 10 target cells into three groups by target antigens: TA (target antigen) 1, 2, and 3. Partial confirmation of the three groups was achieved in the cross-competition assay. The distinction of TA 1 as a group was clear but some cross-reactivity existed between TA 2 and TA 3 cells.  相似文献   
65.
Presensitization and kidney transplant failures   总被引:7,自引:0,他引:7  
Over 1000 kidney transplant patients were tested for cytotoxic antibodies before transplantation.  相似文献   
66.
AIM: To assess the quality of counselling provided to mothers through the programme to prevent mother-to-child transmission (PMTCT) of HIV in South Africa. METHODS: Structured observations of consultations and exit interviews with 60 mothers attending clinics at three purposively selected PMTCT sites across South Africa were conducted. RESULTS: Twenty-two counsellors were observed. The general quality of communication skills was very good, and 73% of HIV-negative mothers were informed of the advantages of exclusive breastfeeding (EBF). However, only one of 34 HIV-positive mothers was informed about the possible side effects of nevirapine, and none was told what to do when it occurred. Only two HIV-positive mothers were asked about essential conditions for safe formula feeding before a decision about an infant feeding option was made. None of the 12 mothers choosing to breastfeed was shown how to position the baby correctly on the breast or asked whether they thought EBF was feasible. Fewer than a quarter of mothers expressed confidence in performing the actions required, and 85% could not define the term EBF. CONCLUSION: The poor quality of counselling in the PMTCT programme will reduce the effectiveness of these programmes. As they are being scaled up, there needs to be far more attention paid towards the counselling of mothers, especially with regards to optimal infant feeding.  相似文献   
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Weight gain during treatment with psychotropic drugs is frequently observed and is assumed to be responsible for non-compliance and for an elevated risk to develop a number of somatic co-morbidities including cardiovascular disorders and type 2 diabetes. Absence of weight inducing effects is therefore a major objective for the development of new compounds. Recently, R121919, the first corticotropin releasing hormone receptor 1 (CRH1R) antagonist, was tested in major depression. Clinical efficacy, safety, and tolerability of this compound could be demonstrated. Since CRH is discussed to be involved in the regulation of appetite and weight, directly and via interaction with leptin, CRH1R antagonists are suspected to influence body weight. Effects of 30 days of treatment with the CRH1R antagonist R121919 on weight and leptin levels in 20 patients suffering from major depression were investigated. No significant weight changes during treatment with R121919 were observed. Furthermore, noeffects on plasma leptin concentrations were found. We conclude that treatment with the CRH1R antagonist R121919 does not affect weight or plasma leptin concentrations in patients with major depression. Together with previous findings indicating safety, tolerability, and clinical efficacy CRH1R antagonists are highly promising as a new treatment option in depression.  相似文献   
69.
BACKGROUND: Early treatment can reduce mortality from heart attacks. However, patient delay, especially among the elderly, has slowed progress in this area. One of the reasons for delay may be because of a lack of knowledge about symptoms of acute myocardial infarction (AMI) and treatment benefits. The Internet is a new and promising source of heart health information, but we know little about how elderly people use this medium. METHODS: This study investigates the demographic and psychosocial variables that are related to Internet access, health information seeking, and information seeking about heart attacks from the Internet among seniors. We interviewed seniors (N = 323) aged more than 65 years and asked them questions about Internet access, health information seeking, and information seeking on heart attacks, as well as demographic information, risk perceptions for AMI, and personal experience with AMI. RESULTS: The results showed that several demographic variables were related to access to the Internet. Only 7% of the seniors who reported access to the Internet had sought information on heart attacks from the Internet. Age, history of AMI, and family history of AMI were significant predictors of information seeking on heart attacks. This suggests that to date only a very small, high-risk group of seniors actually seeks information on heart attack emergencies from the Internet.  相似文献   
70.
Impaction allografting for femoral component revision: clinical update   总被引:5,自引:0,他引:5  
The technique of cancellous impaction allografting with cement aims to reconstitute a bone-deficient proximal femur while also gaining stable fixation of the femoral prosthesis. Some reports of this technique imply it is a system, requiring not just an exacting surgical method, but also a particular implant design, the polished, double-tapered stem. Other series consider it a surgical technique, and have varied the femoral component design, the method of graft delivery, and other elements of the procedure. Our review evaluates the current literature, with the goal of beginning to ascertain whether published results suggest impaction grafting must be considered a system, requiring a particular stem design, or simply another means to achieve femoral reconstruction in the revision setting. The conclusive answer will require randomized, controlled clinical trials to evaluate particular elements of the procedure, and these studies have yet to be done. However, investigators have shown similarly good short-term to intermediate-term results with various femoral stems at numerous centers. Currently, femoral impaction allografting, whether as a system using particular implant designs or as a surgical technique, is an accepted alternative for revision of a failed femoral component, particularly when bone-stock deficiency is present.  相似文献   
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