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In order to assess the impact of nutritional status on the onset of menarche and the association between age at menarche and age at marriage, a survey of 1155 girls, ages 10 through 20, was conducted in a rural area of Bangladesh in March 1976. In order to obtain an estimated mean of age of menarche, probit analysis was used. The mean age of menarche using this technique is estimated at 15.65 for Muslims and 15.91 for Hindus. It was learned that in recent years the age of menarche has increased in a rural area. This increase seems to be associated with malnutrition caused by the war, postwar inflation, floods and famines during the 1971-75 period. When age is controlled for, the prominent effect of weight on menstrual status is evident. 98% of the girls whose weights were 88 pounds or greater had reached menarche compared to only 1% of those weighing less than 66 pounds. Body weight appears to be 1 of the most important factors for the determination of onset of menarche. There exists a seasonality of onset of menarche with a peak in winter. Age of marriage among this rural population has increased and may be associated with the increasing age of menarche. Since both age of menarche and age of marriage have increased, fertility among females age 15-19 may be expected to decrease in the future if this pattern continues. 相似文献
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The aim of the present investigation is to evaluate adrenomedullary hormones and blood glucose responses to intermale aggression in the bandicoot rat. Aggression elicited a rise in adrenaline and noradrenaline content of the adrenal gland and in blood glucose level in the subordinate rats. No significant change was marked in the dominant rats after aggression. It is suggested that during aggression the subordinate rats suffered from psychosomatic stress that resulted in hyperactivity of the adrenal medulla and consequently hyperglycemia. 相似文献
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Dopamine synthesis rate and cyclic AMP concentration were measured in synaptosomes prepared from rat striatum. Dopamine synthesis rate was decreased by the addition of either adenosine deaminase or 8-phenyltheophylline, an adenosine receptor blocker, and was increased by the addition of 2-chloroadenosine. The addition of L-glutamate in the absence of adenosine deaminase decreased both dopamine synthesis rate and cyclic AMP concentration; in the presence of adenosine deaminase, glutamate had no effect on basal dopamine synthesis, but enhanced K(+)-stimulated synthesis. Both these effects of glutamate were abolished in Ca2(+)-free medium or in the presence of 2-amino-5-phosphonovalerate, an N-methyl-D-aspartate (NMDA) receptor blocker. In Mg2(+)-free medium with adenosine deaminase, glutamate enhanced both basal and K(+)-stimulated synthesis. These results suggest that dopaminergic terminals have A2 adenosine receptors, whose activation can stimulate dopamine synthesis by a cyclic AMP-dependent mechanism, and NMDA receptors, which modulate dopamine synthesis by a Ca2(+)-dependent mechanism. 相似文献
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A 14-kilodalton inner membrane protein of Vibrio cholerae biotype e1 tor confers resistance to group IV choleraphage infection to classical vibrios.
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Choleraphage phi 149 differentiates the two biotypes, classical and el tor, of Vibrio cholerae. This phage cannot replicate in V. cholerae biotype el tor cells because the concatemeric DNA intermediates produced are unstable and cannot be chased to mature phage DNA. A V. cholerae biotype el tor gene coding for a 14,000-Da inner membrane protein which destabilizes the concatemeric DNA intermediates by hindering their binding to the cell membrane has been identified. Presumably, a 22,000-Da V. cholerae biotype el tor protein might also have a role in conferring phage phi 149 resistance to cells belonging to the biotype el tor. A nucleotide sequence homologous to the 1.2-kb V. cholerae biotype el tor DNA coding for both the 14,000- and 22,000-Da proteins is present in all strains of classical vibrios but is not transcribed. The nucleotide sequence of the gene coding for the 14,000-Da protein has been determined. 相似文献
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N.A. Chowdhury M. Moniruzzaman N. Nahar N. Choudhury 《World journal of microbiology & biotechnology》1991,7(6):603-606
A locally isolated strain of Micromonospora sp. when grown on different natural cellulosic substrates gave the highest activity of carboxymethylcellulase (34 U/ml) and Avicelase (0.9 U/ml) on rice straw. Sugar cane bagasse was also a good substrate for growth and cellulase production. With commercial cellulosic substrates, highest carboxymethylcellulase (90 U/ml) and Avicelase (2.8 U/ml) activities were when the organism grew on xylan. Saccharification of sugar cane bagasse and rice straw by enzyme preparations of the organism grown on the respective substrates released 5.6 and 5.8 mg reducing sugar/ml. With all enzyme preparations, bagasse was more easily saccharified than rice straw.The authors are with the Atomic Energy Research Establishment, GPO Box 3787, Dhaka 1000, Bangladesh; N.A. Chowdhury, M. Moniruzzaman, and N. Choudhury in the Institute of Food and Radiation Biology, and N. Nahar in the Institute of Nuclear Science and Technology. 相似文献
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Detection of Vibrio cholerae O1 in the aquatic environment by fluorescent-monoclonal antibody and culture methods. 总被引:8,自引:6,他引:2
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A Huq R R Colwell R Rahman A Ali M A Chowdhury S Parveen D A Sack E Russek-Cohen 《Applied microbiology》1990,56(8):2370-2373
Vibrio cholerae O1 in plankton samples collected from ponds and rivers between February 1987 and January 1990 in Matlab, Bangladesh, was detected by the fluorescent-monoclonal antibody (FA) technique. Samples were collected at sites which were monitored fortnightly (fixed sites) as well as at sites that were part of a case-control study. FA results were compared with those obtained by conventional culture methods (CM). A total of 876 samples were collected; V. cholerae O1 was detected in 563 samples (64.27%) by the FA method and in 3 samples (0.34%) by CM. Of the fixed-site plankton samples, 439 (63.62%) were positive by FA and none were positive by CM. Of the 93 case sites sampled on the day after the occurrence of a case of cholera, 73 (78.49%) were positive for V. cholerae O1 by FA and 3 (3.2%) were positive by CM. In comparison, of the 93 first-day sample collections at control sites at the time a case of cholera occurred, only 51 (54.83%) were positive by FA and none were positive by CM. From the data, it is concluded that V. cholerae O1 is present throughout the year in the ponds and rivers of Bangladesh that were examined in this study and that V. cholerae can be detected by FA but not always by CM. The FA procedure was found to be very useful in detecting V. cholerae in plankton, with which it was associated and often occurred in large numbers in the nonculturable stage. Thus, studies investigating the significance of the role of environmental factors in the epidemiology of cholera can be performed effectively by using FA. Such studies are in progress. 相似文献
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