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1.
Play behavior and stress-associated behavior of a captive juvenile gorilla were observed before and after his transfer to a larger and more natural environment. The gorilla was observed for 4 months after the transfer and at 1 and 4 years after the transfer. Throughout his first month in the new environment play decreased dramatically. Although play subsequently increased again 2 months and 1 year after the transfer, it never reached the levels of play in the old environment. Four years after the move his play had decreased again to the low level of his first month in the new environment. Two of his stress-associated behaviors, coprophagy and regurgitation/reingestion, decreased after the transfer. Self-clasping behavior increased initially in the new environment and remained at high levels 1 year after the move. Four years after the move his self-clasping behavior was significantly less than at 1 year after the move; however, it continued to be significantly greater than in the old environment. These findings suggest that larger and more natural environments do not necessarily result in more play activity or a reduction in all stress-associated behavior.  相似文献   
2.
Differences in the function and composition of individual ovarian follicles were noted in Booroola Merino ewes which had previously been segregated on at least one ovulation rate record of greater than 5 (FF ewes, N = 15), 3-4 (F+ ewes, N = 18) or less than 3 (++ ewes, N = 18). Follicles in FF and F+ ewes produced oestradiol and reached maturity at a smaller diameter than in ++ ewes. In FF (N = 3), F+ (N = 3) and ++ (N = 3) ewes, the respective mean +/- s.e.m. diameters for the presumptive preovulatory follicles were 3.4 +/- 0.3, 4.1 +/- 0.2 and 6.8 +/- 0.3 mm and in each of these follicles the respective mean +/- s.e.m. numbers of granulosa cells (X 10(6)) were 1.8 +/- 0.3, 2.2 +/- 0.3 and 6.6 +/- 0.3. During a cloprostenol-induced follicular phase, the oestradiol secretion rates from FF ewes with 4.8 +/- 0.4 'oestrogenic' follicles, F+ ewes with 3.2 +/- 0.2 'oestrogenic' follicles and ++ ewes with 1.5 +/- 0.02 'oestrogenic' follicles were not significantly different from one another. Moreover, the mean total numbers of granulosa cells from the 'oestrogenic' follicles from each genotype were identical, namely 5.4 X 10(6) cells. Irrespective of genotype the mean weight of each corpus luteum was inversely correlated to the ovulation rate (R = 0.91, P less than 0.001). Collectively, these findings support the notion that the maturation of greater than or equal to 5 follicles in FF ewes and 3-4 follicles in F+ ewes may each be necessary to provide a follicular-cell mass capable of producing the same quantity of oestradiol as that from 1-2 preovulatory follicles in ++ ewes.  相似文献   
3.
A marked difference in both the function and composition of individual ovarian follicles was noted in Booroola X Romney ewes (6-7 years of age) which had previously been segregated on at least one ovulation rate record of 3-4 (F + ewes, N = 21) or less than 3 (++ ewes, N = 21). Follicles in F + ewes produced oestradiol and reached maturity at a smaller diameter than in ++ ewes. In F+ ewes (N = 3), the presumptive preovulatory follicles were 4.4 +/- 0.5 (s.e.m.) mm in diameter and contained 2.1 +/- 0.3 X 10(6) (s.e.m.) granulosa cells, whereas in ++ ewes (N = 3), such follicles were 7.3 +/- 0.3 mm in diameter and contained 6.5 +/- 0.8 X 10(6) cells. During a prostaglandin (PG)-induced follicular phase, the secretion rate of oestradiol from ovaries containing 3 presumptive preovulatory follicles in F + ewes was similar to that from ovaries with only one such follicle in ++ ewes. We suggest that the putative 'gene effect' in F + ewes is manifested during early follicular development and that it may be mediated via an enhanced sensitivity of granulosa cells to pituitary hormones. As a consequence, the development of 3 preovulatory follicles in F + ewes may be necessary to provide a cell mass capable of producing the same quantity of oestradiol as that from one preovulatory follicle in ++ ewes.  相似文献   
4.
We present complete restriction endonuclease cleavage site maps of the bacteriophage P22 chromosome for 16 enzymes with six base recognition sequences, thereby positioning 116 new sites on the chromosome. Twenty-four such restriction maps for P22 DNA, containing 162 sites, have now been completed, and three enzymes were found that did not cut P22 DNA. Our results are consistent with the ideas that ClaI does not cleave the methylated recognition sequence ATCGA(me)T or A(me)TCGAT and StuI does not cleave the methylated recognition sequence AGGCC(me)T.  相似文献   
5.
用间接酶联免疫吸附实验(ELISA)对新近诊断的179例血液病患者血清巨细胞病毒(HCMV)IgM和IgA抗体进行了检测。阳性率分别为11,17%11,73%,明显高于对照人群(4,76%和3,97%),提示血液病患者由于免疫功能下降,易于发生HCMV活动性感染。  相似文献   
6.
At 37 degrees C 125I-labelled human (h) FSH (NIAMDD-hFSH-I-3) bound rapidly to granulosa cells from Booroola and Romney ewes with 50% maximum binding achieved after 3 min and equilibrium being reached within 45 min, irrespective of whether the cells were obtained from the FF, F+ or ++ Booroola genotypes or from Romney ewes. Binding of 125I-labelled FSH followed second order kinetics and there was no effect of follicle diameter (1-2.5 mm vs greater than or equal to 3 mm). Irrespective of breed, genotype or follicle size, the mean (+/- s.e.m.) calculated association rate constant, (ka) was 7.3 (+/- 0.8) x 10(5) litres mol-1 sec-1 (n = 12). Dissociation of receptor bound 125I-labelled hFSH was less than 5% after 30 min and low but variable (i.e. between 0 and 30%) after 2-6 h irrespective of breed, genotype or follicle size. No gene-specific differences were noted in binding specificity between F+ and ++ genotypes: studies were not performed with cells from FF ewes because of insufficient cells. The binding of 125I-labelled hFSH could be displaced with sheep FSH (NIH-FSH-S16; 10% cross-reaction) and FSH-P (2.5% cross-reaction) but other sheep pituitary hormones and hCG showed little or no cross-reaction (less than or equal to 0.1%). The calculated binding capacities (Bmax) and equilibrium dissociation constants (Kd) for 125I-labelled hFSH binding to granulosa cells did not differ between the Booroola genotypes or between Booroola or Romney follicles of different diameter (i.e. 1-2.5 mm; or greater than or equal to 3 mm). The overall mean +/- s.e.m. (n = 24) Bmax and Kd values were 16.7 +/- 0.8 fm/mg protein (i.e. approximately 800 available receptor binding sites/cell) and 1.1 +/- 0.1 nM respectively. Collectively, these findings suggest that the earlier maturation of follicles in FF or F+ ewes compared to ++ ewes is unlikely to be due to gene-specific differences in the FSH binding characteristics of the granulosa cells.  相似文献   
7.
We report DNA and clinical analyses of cystic fibrosis (CF) in two previously unstudied, genetically isolated populations: Pueblo and Navajo Native Americans. Direct mutation analysis of six mutations of the CFTR gene--namely, delta F508, G542X, G551D, R553X, N1303K, and W1282X--was performed on PCR-amplified genomic DNA extracted from blood samples. Haplotype analyses with marker/enzyme pairs XV2c/TaqI and KM19/PstI were performed as well. Of the 12 affected individuals studied, no delta F508 mutation was detected; only one G542X mutation was found. None of the other mutations was detected. All affected individuals have either an AA, AC, or CC haplotype, except for the one carrying the G542X mutation, who has the haplotype AB. Clinically, six of the affected individuals examined exhibit growth deficiency, and five (all from the Zuni Pueblo) have a severe CF phenotype. Four of the six Zunis with CF are also microcephalic, a finding not previously noted in CF patients. Our DNA data have serious implications for risk assessment of CF carrier status for these people.  相似文献   
8.
Biological Trace Element Research - The essential trace elements in 30 traditional Chinese medicines, (24 tonics and 6 nontonics) were determined by proton-induced X-ray emission. The...  相似文献   
9.
露水草的光合特性及其生态学意义   总被引:2,自引:0,他引:2  
用盆栽和遮阴试验研究了露水草(Cyanotis arachnoidea Clarke) 的光合作用特征,比较了不同遮光水平对光合速率、光合器官特性及光合产量的影响。结果如下:1.露水草是一种耐阴偏阳的C3 类草木植物,其光合作用的光饱和点约为650 μm ol·m - 2·s- 1,光补偿点约为17 μm ol·m - 2·s- 1,且具有高达130×10- 6的CO2 补偿点。2.露水草的最大净光合速率为12.45 μm ol·m - 2·s- 1。叶片净光合速率的日变化规律呈双峰曲线,主峰在11~12 时,次峰在15时左右。3.遮光20% ~50% 有利于露水草的生长。与对照相比,叶片中叶绿素b 的含量增加了47% ~83% ,并且由于净光合速率(相对光合速率)的提高,使光合生产量增加了12% ~18% 。  相似文献   
10.
 以淀粉珠为载体的亲和层析法分离纯化高温α淀粉酶张学忠,宋伦,王群,吴晓霞,唐锌进(吉林大学酶工程国家重点实验室,长春130023;南京师范大学生物系,南京210024)金凤燮等人从酒曲中筛选出高产热稳定α淀粉酶的菌株,命名为Bacillussp-JF...  相似文献   
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