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101.
Brain enzymes convert the opioid peptide beta-endorphin (beta E-(1-31)) to alpha- and gamma-endorphin and to several non-opioid fragments by further cleavage of the tyrosine residue or acetylation. Several of these peptides selectively affect brain functions. alpha-Endorphin (beta E-(1-16)) and relate non-opioid fragments (beta E-(2-16), beta E-(2-9) a.o.) like amphetamine, delay extinction of pole-jumping avoidance behavior and facilitate passive avoidance behavior. In addition these peptides enhance the stereotyped sniffing response induced by the injection of apomorphine into the nucleus caudatus. The fragment beta E-(10-16) inhibits, like serotonin and antidepressants, the behavioral effects of melatonin injected into the nucleus accumbens. gamma-Endorphin (beta E-(1-17)) has inherent opioid and neuroleptic-like properties, e.g. demonstrated by a naloxone reversible inhibition of hypermotility induced by apomorphine following injection into the nucleus accumbens. Also the non-opioid gamma-type endorphins (e.g. DT gamma E (beta E-(2-17) and DE gamma E (beta E-(6-17)) mimic certain effects of neuroleptics. These peptides facilitate extinction of pole-jumping avoidance behavior, attenuate passive avoidance behavior and antagonize the hypomotility and stereotyped sniffing induced by apomorphine injected into the nucleus accumbens and pyriform cortex respectively. These and other behavioral studies, including grasping responses, brain stimulation reward, food and other positively rewarded behavior, indicate that the action of alpha-type endorphins is in some aspects comparable to that of psychostimulants, while the effects of gamma-type endorphins are comparable to those of classical as well as atypical neuroleptics. Indeed, gamma-type endorphins have antipsychotic effects in a category of schizophrenic patients.  相似文献   
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Distal metatarsal osteotomy for hallux valgus in the middle-aged patient   总被引:1,自引:0,他引:1  
Thirty-eight distal metatarsal osteotomies for hallux valgus in middle-aged patients between the ages of 50 and 67 years were performed over a period of five years. None of the patients could be rated with an excellent result. Good results were noted in only 52.6%. Poor results were attributable to imperfect surgical technique, severity of preoperative deformity, osteoporosis, and preexisting osteoarthritic changes at the first metatarsophalangeal joint.  相似文献   
105.
BACKGROUND: The aim of this study was to determine the effect of laser refractive surgery on the offensive performance of professional baseball players. METHODS: Extensive search of the public media was conducted to determine which major league baseball players had undergone laser refractive surgery and when the procedure was performed. Baseball performance data were then used to determine presurgery and postsurgery baseball performance averages. A total of 17 position players were identified; however, 5 of these players were not considered in the analysis owing to insufficient playing experience either before or after the laser procedure. RESULTS: No statistically significant or practically significant difference was found between the presurgery and postsurgery means on either on-base percentage (P = 0.31), batting average (P = 0.39), slugging percentage (P = 0.66) or on-base plus slugging (OPS; P = 0.997) of major league baseball players. CONCLUSIONS: These preliminary findings suggest that professional baseball players should not expect a laser refractive surgical procedure to significantly improve their offensive baseball performance, despite the elimination of glasses or contact lens wear.  相似文献   
106.
Single doses of enalapril maleate 10 mg and frusemide 80 mg do not significantly affect the pharmacokinetics of each other when taken concomitantly. Their concomitant use may be associated with more adverse effects than with the individual entities.  相似文献   
107.
Pattern reversal stimuli are widely used for electrophysiological examination of the visual system. To investigate the mechanisms contributing to the pattern reversal EP (PREP) we performed experiments with a trained alert macaque monkey, using both contrast and motion stimuli. It was found that, as in man, for parafoveal and peripheral stimulation the PREP can be constructed from the EPs to the onset and offset of pattern motion. On the other hand foveal stimulation activates the contrast mechanism only.Our conclusion is that pattern reversal data should be considered with caution since pattern reversal can activate motion as well as contrast mechanisms. This ambiguity is not present in the pattern appearance-disappearance stimulus.  相似文献   
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Abstract: Syncope, irreversible shock, and respiratory and circulatory arrest developed in a 54-year-old diabetic man chronically dialyzed with a subclavian catheter (SC) minutes after the end of a dialysis session. Resuscitation attempts remained unsuccessful. During the resuscitation attempt, a blood analysis showed severe hyponatremia, acidosis, and hypochloremia. Respiratory and cardiac arrest developed during dialysis in a 64-year-old woman on chronic SC dialysis. Resuscitation was unsuccessful; chloremia levels were 79 mEq/L, and calcemia levels were 20 mg%. Both patients were dialyzed with a standard dialysate solution. The reasons for the electrolyte disturbances could not be explained technically. The autopsy showed myocardial perforation by the SC and accumulation in the pericardium of the fluids administered during the resuscitation attempt (e.g., glucose 5%, bicarbonate, Ca gluconate, human albumines), thus explaining the erroneous electrolyte results. The reason for the perforation was a too-rigid central femoral vein catheter, erroneously labeled a subclavian catheter by the supplying firm. Because of a syndrome of progressive vena subcla-via and vena cava sclerosis with insufficient arterial phase flow and venous-phase bleeding around the puncture site during single-needle dialysis, the original SC had to be replaced by a longer one with the tip located in the atrium (this SC was actually a femoral catheter). Analysis of the fluid aspirated through the SC can determine the diagnosis in sudden death of SC dialysis patients.  相似文献   
110.
Summary The complete long terminal repeat (LTR) nucleotide sequence of the chimpanzee foamy virus isolate SFV-6 was determined. Its 1761-bp size makes it the longest LTR reported to date among all retroviruses. Since the length of its LTR is similar to that of other simian isolates while its sequence homology is closer to that of HFV, SFV-6 genetic structure appears to be intermediate between simian and human foamy viruses. Transient expression assays demonstrate that SFV-6 encodes a transactivator of viral gene expression directed either by its own LTR or by heterologous promotors like HFV and HIV-1 LTRs. Our data also provide evidence for cross-transactivation between SFV-6 and HFV.  相似文献   
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