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991.
The oxygen transmissibilities (Dk/L) of a set of 48 contact lenses made from 8 different materials were measured by 4 laboratories. The L/Dk measurements from each laboratory were compared and correlated. Samples which were not masked with a fixed front surface aperture during measurement were corrected for edge effects. This paper shows that provided L/Dk is calculated for each lens using the same technique and Dk is derived using a graphical method of calculation, similar results can be obtained by all laboratories. However, the agreement was less good for materials of Dk greater than 70 x 10(-11) (cm2/s) (ml O2/ml x mm Hg).  相似文献   
992.
Evaluation of program implementation can help illuminate negative results of school-based smoking prevention programs. In three conventional quasiexperimental evaluations, no statistically significant impacts of smoking prevention programs on children's knowledge, attitudes, intentions, or behavior were detected. Complementary evaluations of program implementation along several dimensions using naturalistic methods suggested reasons for null effects were different at each site. These data were used to form hypotheses and recommendations for future interventions.  相似文献   
993.
According to the data of tetrasolium nitroblue test and titer of the blood serum antibodies to the most frequently cultured microflora in complex treatment of 27 patients with diffuse purulent peritonitis, it was established, that the use of ultraviolet irradiation of the blood stimulated the specific and non-specific organism resistance.  相似文献   
994.
The authors have thoroughly studied the versions of anatomic structure, peculiarities of blood circulation and innervation of lateral arm graft at 20 recent cadavers. The graft can be utilized in different modifications; cutaneofascial, subcutaneofascial, musculocutaneous, osteocutaneous. In the clinic were made 8 free microsurgic transplantations of lateral arm graft for plasty of tissues of different genesis in functionally important zones of hand and foot. In long-term post-operative period all patients demonstrated good functional and cosmetic results.  相似文献   
995.
On the basis of analysis of surgical treatment of 753 patients with coxarthrosis during 1970-1987, the authors set forth the stages of arthroplasty development in the USSR, using the experience of the Kharkov research institute of orthopaedics and traumatology named after M. I. Sitenko on the problems of arthrodesis operations, endoprosthetics and biological arthroplasty. In the article are presented the peculiar features of diagnostic and surgical tactics in case of patients with idiopathic and dysplastic coxarthrosis; operation technique for each form is presented in details. The authors have developed a new perosseous access to the hip joint, which made a good showing and permits to preserve the integrity of periarticular muscles and neurovascular formations. Application of the given access made possible the extension of indications for arthroplasty in case of grave forms of coxarthrosis, met earlier in a reserved manner.  相似文献   
996.
997.
998.
Morbidity among anaesthetists   总被引:1,自引:0,他引:1  
Anaesthetists may be exposed to a number of occupational hazards. These include exposure to infections, environmental pollution with volatile anaesthetic agents and psychological and stress-related illness which may predispose to drug dependence or suicide.  相似文献   
999.
Cyclosporine A inhibition of microcystin toxins   总被引:2,自引:0,他引:2  
Cyclosporine A (CyA) given i.v. at a dose of 1.25 mg/mouse blocks a subsequent i.v. lethal dose (1.7-1.8 x LD50) of microcystin-LR for 24 hr, and is about 50% protective at 48 hr. Conversely, the fraction of mice that can be rescued by CyA (0.2 mg/mouse) after a lethal dose of microcystin-LR decreases rapidly with a pharmacodynamic half-time of only about 100 sec. The prophylactic action of CyA was tested against lethal doses of four microcystins. The acute lethality of 1.7-1.8 x LD50 dose of microcystin-LR, -RR, -LY, or -LA given 1 hr after administration of 0.2 mg of CyA is 0%, 0%, 58%, or 100%, respectively. Even a 0.6 mg/mouse dose of CyA is ineffective prophylaxis against a lethal dose of microcystin-LA. The inhibitory potency of CyA on microcystin toxicity can be completely reversed by the single L-amino acid substitution of alanine for arginine in the microcystin.  相似文献   
1000.
Orthotopic liver transplantation was performed in 20 pigs. Serum total bile acids (STBA) were determined and their profile compared with standard early function parameters: total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactic acid. In phase I, the STBA level was 32.89 +/- 1.29 mumol/l. In phase II, STBA accumulated to 84.46 +/- 15.25 mumol/l (p less than 0.01), followed by hepatic clearance in phase III (63.61 +/- 9.71 mumol/1; NS). Between phase III and 6- and 12-hour samples, STBA decreased progressively, reaching values of 33.63 +/- 7.05 mumol/l at 24 h. AST was elevated in phases I, II, III, and at 6, 12 and 24 h (p less than 0.001), as was ALT (but with insignificant differences). Thus, STBA and their profile appear to be earlier and more specific indicators of early graft function than conventional parameters.  相似文献   
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