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61.
Report on two fatalities due to stingrays   总被引:1,自引:0,他引:1  
  相似文献   
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Summary: A case of pulmonary candidiasis successfully treated with 5-fluorocytosine†is reported. No side effects due to the drug were observed.  相似文献   
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Marine biotoxins: a new source of medicinals   总被引:1,自引:0,他引:1  
B W Halstead 《Lloydia》1969,32(4):484-488
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PURPOSE: Testicular hypotrophy is the most widely accepted indication for correcting adolescent varicocele. Previous studies in adolescents have shown a relationship between increasing grade of varicocele and the likelihood of testicular hypotrophy. As this relationship has significant clinical implications, we studied the correlation between grade and testicular volume disproportion in our adolescent varicocele population. MATERIALS AND METHODS: We reviewed the adolescent varicocele database at our institution. A total of 168 patients 8 to 21 years old were studied. We routinely calculated testis volumes using scrotal ultrasound. Testicular disproportion was calculated using the equation [(size of unaffected testis) - (size of affected testis)]/(size of unaffected testis) x 100%. Disproportion was categorized as less than 10%, 10% to 20% and more than 20%. Varicoceles were graded by an attending urologist with the patient standing, using the system of Dubin and Amelar. Analysis of variance and Pearson chi-square indicated no significant differences in volume differential between varicocele grades. RESULTS: Mean +/- SD volume differential was 18% +/- 15% for grade I, 25% +/- 20% for grade II and 19% +/- 14% for grade III. ANOVA revealed no significant difference in mean volume differential between the 3 varicocele grades (p = 0.10). When categorizing patients into 3 levels of volume differential (less than 10%, 10% to 20%, more than 20%) no significant correlation was observed between varicocele and volume differential (p = 0.48, chi-square test). CONCLUSIONS: Grade of varicocele does not correlate with presence or severity of testicular disproportion in adolescent boys with varicocele as measured by scrotal ultrasound.  相似文献   
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Rats were made hyperphagic by 6-hydroxydopamine (6-OHDA) injected bilaterally into the ventral midbrain; then they were restricted to a 6h/day feeding schedule and tested for appetite suppression with amphetamine and fenfluramine in randomized order. Amphetamine anorexia was diminished while fenfluramine anorexia was enhanced (both P<0.001). The opposite effect on fenfluramine anorexia shows that the effect of 6-OHDA on amphetamine anorexia was not due to hyperphagia masking the anorexia. Norepinephrine in the forebrain was 90% depleted, but DA and serotonin levels were within 9% of normal. These results demonstrate a new way to dissociate amphetamine and fenfluramine anorexia, as others have done with lateral hypothalamic lesions or DA depletion. The 6-OHDA injections, which were of a type that cause hyperphagia, apparently destroyed a substrate for amphetamine anorexia and also facilitated a substrate for fenfluramine anorexia.  相似文献   
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Studies have shown that intermittent sugar availability (12 h/day) produces signs of dependence in rats, including escalation of intake, mu-opioid and dopamine receptor changes, behavioral and neurochemical indices of withdrawal, and cross-sensitization with amphetamine. "Deprivation-effect" paradigms, whereby abstinence from a substance results in enhanced intake, are often used to measure "craving" for drugs of abuse, such as alcohol. The present study used operant conditioning to investigate consumption of sugar after abstinence in rats selected for glucose avidity. The experimental group was trained on a fixed ratio (FR-1) schedule for 25% glucose for 30 min/day for 28 days and also had glucose access in the home cages for an additional 11.5 h daily. The control group had only the 30-min/day access to glucose in the operant chambers. Then, both groups were deprived of glucose for 2 weeks. After this period of abstinence, animals were put back in the operant chambers. The experimental group responded significantly more than ever before, and significantly more than the control group. In conclusion, daily 12-h access to sugar, in the paradigm used, can result in an altered neural state that lasts throughout 2 weeks of abstinence, leading to enhanced intake. Together with previous results, this deprivation effect supports the theory that animals may become dependent on sugar under selected dietary circumstances.  相似文献   
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