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991.
Mice ran in a circular runway. Some received milk at every third circuit in a designated direction, clockwise or counterclockwise, in daily 1000-s sessions. Under control conditions, about 10 times as many circuits were made in the reinforced direction as in the non-reinforced direction. Cocaine (10, 30, 100 µM/kg) had little effect on the total number of circuits, but progressively increased the number in the non-reinforced direction. Chlorpromazine (1, 3, 10, 30 µM/kg) caused a monotonic decrease in total number of circuits and in number in non-reinforced direction. At the highest doses the proportion in the non-reinforced direction was increased. Mice, untrained in the runway and with no reinforcement of circuits in either direction, made many fewer total circuits than when running was reinforced and about equal numbers were in clockwise and in counterclockwise directions. Cocaine greatly increased the total number of circuits. As in the subjects whose running was reinforced, cocaine led to a much higher tendency for mice to run in a single direction. The similarities between the tendency to run in one direction after cocaine and the rotational behavior of rodents seen after cocaine and amphetamine suggest a common mechanism.  相似文献   
992.
A new Soviet laser device for multiple-purpose ophthalmologic application is described. The design is based on neodymium-doped glass laser with radiation at a 1.06 micron wavelength in a Q-spoiled mode and YAG laser with radiation frequency doubling at a wavelength of 0.532 micron in continuous operation. Clinical potentialities of this laser design in the treatment of abnormalities of the anterior and posterior segment of the eye were studied in the treatment of 48 patients (48 eyes). The results evidence that the device is fit for coagulation as well as for mechanical destruction of tissue.  相似文献   
993.
We present two cases of neonatal pleural effusion, a relatively rare condition, most commonly due to chylothorax. One had bilateral hypoplastic lungs and the other suffered birth asphyxia. Both died before any treatment could be initiated.  相似文献   
994.
995.
Interindividual variations in the immunosuppressive effect of Cyclosporine have been observed in clinical organ transplantation. Searching for an in vitro correlate we investigated a possible relation between inhibition of alloresponsiveness by CsA and the HLA phenotypes of the responder or stimulator in mixed lymphocyte reactions. Peripheral blood mononuclear cells from 28 healthy volunteers were used as responder or stimulator cells (gamma-irradiated) and the inhibitory effect of graded amounts of CsA was determined in 130 criss-cross combinations. Sensitivity of alloresponsiveness to the drug was expressed as the dose causing 50% inhibition (ED50) and was read from the inhibition curves generated after four-parameter logistic curve fitting. ED50 ranged from 0.35 ng/ml to 33.4 ng/ml and correlated only weakly with the magnitude of the response (r = 0.12). In MLC with HLA DR4-positive responder cells, ED50 was significantly lower (Pc = 0.0035, Kruskal Wallis) when compared with MLC with responder cells of other DR haplotypes. For HLA DR5-positive responder cells ED50 was significantly higher (Pc = 0.042) when compared with DR5-negative responder cells. No significant correlation between ED50 and any particular haplotype of the stimulator cells could be observed. Sensitivity to CSA did not differ in MLC with 1 or 2 mismatches in the HLA-DR locus. In summary, we found that sensitivity of in vitro alloreactivity was different for particular HLA DR phenotypes, which may have important implications for the immunosuppressive therapy of transplanted patients with cyclosporine.  相似文献   
996.
We reviewed the records of 1,156 patients treated for acute staphylococcal osteitis or septic arthritis over a 12-year period; 38 had been critically ill with evidence of multiple-organ involvement and 30 (79%) had features of the toxic shock syndrome. The mortality rate of these 38 patients was 13% and the long-term orthopaedic complication rate was 39%. The diagnosis and management of patients with osteitis or septic arthritis, disseminated staphylococcal disease, and the toxic shock syndrome is discussed.  相似文献   
997.
998.
The 2-(2-Bromophenyl)-acetaldehyde acetals 8 are treated with n-BuLi and the aldehydes 7 and 11 to form the hydroxyacetales 9 and 12, respectively. 9 is cyclized under acidic conditions to the epoxybenzoxocine 2; analogously 12 yields the epoxydibenzoxocine 14.  相似文献   
999.
1000.
Authors describe a case of isolated posttraumatic neuropraxy of the musculocutaneous nerve. With the presentation of this very rare case attention is called, based on literary date, to the fact that the above injury can be mixed with the distal tendon rupture of the biceps.  相似文献   
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