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41.
Studies from Africa have demonstrated that black people have higher vitamin B12 (cobalamin) levels than do white people. The authors compared healthy white people, black people, and Latin-Americans in the United States. Their study is also the largest in which the effect of race and sex on the cobalamin levels has been examined. Analysis of 233 healthy subjects showed that black people had significantly higher (P less than 0.0001) vitamin B12 levels than did white people. Latin-Americans had levels intermediate between those of white and black people, although their levels were significantly different only in comparison with white people (P = 0.0029). Based on the study of 305 healthy subjects, no sex difference in vitamin B12 levels was noted. Conflicting claims have been made on sex difference in the past. The authors conclude that there is a racial but not a sex difference in vitamin B12 levels in the United States. Like African black people, black people and Latin-Americans in this country have significantly higher vitamin B12 levels than do white people. This finding supports the thesis that genetic factors contribute to the racial differences in vitamin B12 levels.  相似文献   
42.
The distribution of cardiac output (c.o.) was measured by the radioactive microsphere method in rats at different time intervals after the implantation of carrageenanimpregnated sponges. The amount of blood distributed to the developing granulomata increased from day 5 after sponge implantation to day 7, but showed no further increase at day 10. A similar pattern in blood flow was observed in the skin covering the granulomata. Injection of PGE1 (100 ng) into the sponges led to an increase in blood flow, the magnitude of which became gradually larger between days 5 and 10. A similar, though less marked increase in sensitivity to PGE1 was observed in the skin covering the granulomata, PGE1 causing a significant increase in blood flow to the skin on day 10. These changes in sensitivity to exogenous PGE1 may be due to decreasing levels of endogenous PGE and/or maturation of the newly formed blood vessels in the granulation tissue.  相似文献   
43.

Background  

Colon cancer is the second leading cause of cancer deaths in the western world. If detected early, colorectal cancer is one of the most treatable forms of cancer. Unfortunately, very few people are screened. N-myristoyltransferase (NMT) catalyzes myristoylation of various proteins including oncoproteins. We have demonstrated earlier the alteration of NMT activity during the progression of colorectal cancer and established NMT as a putative therapeutic target for cancer.  相似文献   
44.
Three strains of Escherichia coli isolated from infectious processes in a calf, a dog, and a cat were examined for their capacity to produce disease or death, or both, in newborn gnotobiotic piglets. The O groups represented by these particular strains of E. coli were O4: (canine origin), O6: (feline origin), and O39: (bovine origin). All three isolates upon oral administration proved to be pathogenic. Infection with the E. coli O4: (canine) or O39: (bovine) consistently produced signs of enteric coli-bacillosis and death in all 1- and 3-day-old piglets within 24 to 48 hr. The O6: (feline) isolate, on the other hand, produced a marked polyserositis and generally required 6 to 7 days to kill a piglet. Only the respective type of E. coli used in the particular trial was recovered from the diseased piglets. These findings suggest the possible role of domestic animals and household pets in the spread of potentially pathogenic E. coli to other species.  相似文献   
45.
BCA200 has been described as a 200,000 Mr monomeric cell surface glycoprotein associated with human breast cancer. Since the physical properties and cellular distribution of BCA200 resemble those of c-erbB-2, antibodies to BCA200 were tested for the ability to bind a recombinant protein containing the c-erbB-2 extracellular domain (erbB-2 ECD). Three antibodies to distinct epitopes of BCA200 reacted with erbB-2 ECD but not with a control protein expressed in a similar baculovirus lysate. Control myeloma proteins and antibodies to four other antigens did not react with erbB-2 ECD. A protein with the expected molecular weight for erbB-2 ECD was also immunoprecipitated by anti-BCA200 antibody 520C9. We conclude that BCA200 is another synonym for c-erbB-2.  相似文献   
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48.
A key recommendation of the National AIDS Control Programme‐IV of India was to develop new strategies for geo‐prioritization of the human immunodeficiency virus (HIV) epidemic. We conducted this study to categorize the districts in Maharashtra (India) based on a multidimensional framework for geo‐prioritization of services. Programmatic data on trends of HIV prevalence, coverage of marginalized populations and vulnerability factors were included. A composite indicator based on these was developed, and the cumulative score was calculated for each district. HIV prevalence among general population has declined steadily from 0.60% in 2007 to 0.33% in 2017. The programme coverage was stable but inadequate for men who have sex with men (MSM). The coverage for female sex workers (FSWs) was inadequate and reduced over time. Nine districts were categorized as high priority, 13 as moderate priority and 11 were classified as low‐priority districts based on burden and vulnerability for HIV. The high‐priority districts were Pune, Solapur and Yavatmal for FSW interventions and Pune, Thane and Latur for MSM interventions. This multidimensional indicator is based on existing programmatic data, dynamic and can be made state‐specific. It is useful to categorize and prioritize districts for allocation of resources and geo‐prioritization of services in resource limited settings.  相似文献   
49.
Effect of diphenhydramine was investigated on withdrawal signs in lorazepam dependent rats. Physical dependence was produced by giving lorazepam admixed with the food in the following dose schedule: 10 x 4, 20 x 4, 40 x 4, 80 x 4 and 120 x 7 (mg/kg, daily x days). The parameters observed during the periods of administration of lorazepam and after its withdrawal were spontaneous locomotor activity (SLA), body temperature, reaction time to pain, foot shock aggression (FSA) and audiogenic seizures. Diphenhydramine was administered orally in the dose schedules of once daily (10, 20 and 40 mg/kg) and twice daily (5, 10 and 20 mg/kg) in separate groups during the withdrawal period. The withdrawal signs observed in control group (without diphenhydramine) were hyperkinesia, hyperthermia, hyperaggression and audiogenic seizures. Hyperkinesia and hyperthermia were blocked in all the groups of diphenhydramine-treated rats. FSA was inhibited only by diphenhydramine (10 and 20 mg/kg) given twice daily. Audiogenic seizures were completely blocked by once daily (20 and 40 mg/kg) as well as twice daily (20 mg/kg) doses of diphenhydramine. It may be concluded that diphenhydramine exerts a protective effects on benzodiazepine withdrawal syndrome.  相似文献   
50.
Episodic Vertigo Comprises a large group of patients seen in any neurootology unit. A total of 118 subjects were reviewed who attended the neurootology unit. Vertigo of shorter duration was noted in 78 and of longer duration in 40 cases. 51 cases showed bilateral neurosensory deafness, 15 cases had bilateral and another one case had unilateral conductive loss. Spinovestibular tests were abnormal in all cases of vertigo of short duration but only 29 cases showed abnormal reflex in patients with a long duration of illness. Thermal vestibulometry revealed hyporeflexia in 33 cases, directional preponderance in 30 cases and 4 cases showed hyperreflexia 28 cases had peripheral lesions while 81 cases had central lesions. The acute cases showed significant improvement on follow up except cases with abnormality in thermal vestibulometry . The cases with positional nystagmus showed improvement with head and body balance exercises expect in those who received treatment with vestibulosedative and vestibular suppersive drugs. Hearing loss remained the same except in patients with middle ear disorders.  相似文献   
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