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171.
PURPOSE: The aim of this study was to evaluate chromatin condensation of human spermatozoa following swim-up compared to glass-wool separation. Semen aliquots from men attending an andrological outpatient clinic were processed by means of a swim-up procedure and glass-wool filtration. Chromatin condensation was recorded using aniline blue staining and results were reported according to color intensity of stained sperm heads. Morphometric measurements of sperm heads were performed on stained sperm samples. RESULTS: Glass-wool filtration resulted (i) in a significantly higher total motile sperm count (P < 0.0005) compared to swim-up and (ii) in a significantly higher percentage of normal chromatin-condensed spermatozoa compared to the ejaculate (P < 0.01). CONCLUSION: In contrast, comparing swim-up to the ejaculate, the percentage of matured nuclei (unstained spermatozoa) retrieved following swim-up was significantly lower (P < 0.005). Glass-wool filtration separates human spermatozoa according to motility and size of the sperm head. The size of the sperm head closely correlated with the chromatin condensation quality. 相似文献
172.
173.
dos Santos RR 《Canadian Metallurgical Quarterly》1995,51(21):15540-15546
174.
The ACS is a clinical entity that develops from progressive, acute increases in IAP and affects multiple organ systems in a graded fashion because of differential susceptibilities. The gut is the organ most sensitive to IAH, and it develops evidence of end-organ damage before the development of the classic renal, pulmonary, and cardiovascular signs. Intracranial derangements with ACS are now well described. Treatment involves expedient decompression of the abdomen, without which the syndrome of end-organ damage and reduced oxygen delivery may lead to the development of multiple organ failure and, ultimately, death. Multiple trauma, massive hemorrhage, or protracted operation with massive volume resuscitation are the situations in which the ACS is most frequently encountered. Knowledge of the ACS, however, is also essential for the management of critically ill pediatric patients (especially those with AWD) and in understanding the limitations of laparoscopy. The role of IAH in the pathogenesis of NEC, central obesity co-morbidities, and pre-eclampsia/eclampsia remains to be fully studied. 相似文献
175.
RR Gordon 《Canadian Metallurgical Quarterly》1995,345(8965):1640-1641
176.
DNA obtained from a human sputum isolate of Mycobacterium tuberculosis, NTI-64719, which showed extensive dissemination in the guinea pig model resulting in a high score for virulence was used to construct an expression library in the lambda ZAP vector. The size of DNA inserts in the library ranged from 1 to 3 kb, and recombinants represented 60% of the total plaques obtained. When probed with pooled serum from chronically infected tuberculosis patients, the library yielded 176 recombinants with a range of signal intensities. Among these, 93 recombinants were classified into 12 groups on the basis of DNA hybridization experiments. The polypeptides synthesized by the recombinants were predominantly LacZ fusion proteins. Serum obtained from patients who were clinically diagnosed to be in the early phase of M. tuberculosis infection was used to probe the 176 recombinants obtained. Interestingly, some recombinants that gave very strong signals in the original screen did not react with early-phase serum; conversely, other whose signals were extremely weak in the original screen gave very intense signals with serum from recently infected patients. This indicates the differential nature of either the expression of these antigens or the immune response elicited by them as a function of disease progression. 相似文献
177.
The recognition of odorants by olfactory receptors represents the first stage in odor discrimination. Here, we report the generation of an expression library containing a large and diverse repertoire of mouse olfactory receptor sequences in the transmembrane II-VII region. From this library, 80 chimeric receptors were tested against 26 odorants after transfection into HEK-293 cells. Three receptors were identified to respond to micromolecular concentrations of carvone, (-) citronellal, and limonene, respectively. We also found that the mouse I7 receptor, unlike the rat I7 receptor, prefers heptanal instead of octanal, as a result of a single valine-to-isoleucine substitution. This finding represents the beginning of a molecular understanding of odorant recognition. The identification, on a large scale, of cognate receptor-odorant interactions should provide insight into olfactory coding mechanisms. 相似文献
178.
We have demonstrated the presence of epidermal growth factor (EGF) and its receptors in human non-gestational corpora lutea. To determine further the characteristics of EGF receptor binding, we examined 30 human corpora lutea throughout the luteal phase and during pregnancy. Scatchard plots of EGF binding in 29 of the 30 corpora lutea were curvilinear, suggesting negative co-operativity. The mean +/- SE of the association constant Ka was (0.9 +/- 0.2) x 10(9) l/mol, the dissociation constant Kd was (2.2 +/- 0.3) x 10(-9) mol/l and the number of binding sites (Rt) was (15.8 +/- 2.1) x 10(-19) mol/micrograms protein for non-gestational corpora lutea. The Kd increased significantly in late pregnancies compared to early pregnancies (P = < 0.005), while Rt was significantly higher in term pregnancies than in either early pregnancy (P < 0.01) or the menstrual cycle (P < 0.001). Corpora lutea atretica (n = 2) and ovarian stroma (n = 6) did not show any EGF binding activity. Our findings demonstrate the presence of specific EGF receptors in human corpora lutea of both the menstrual cycle and pregnancy. The changes in EGF binding parameters in early pregnancy suggest that there may be a relationship between the role of EGF and ovarian steroidogenesis. 相似文献
179.
DE Sandberg MH MacGillivray RR Clopper C Fung L LeRoux DE Alliger 《Canadian Metallurgical Quarterly》1998,83(4):1134-1142
Several studies have investigated the quality of life (QOL) of GH-deficient (GHD) adults who, as children, had been treated with GH. Variable findings are probably related to sample heterogeneity and disparate research methodologies and designs, particularly the choice of control or comparison groups. In addition to comparing a relatively large sample to questionnaire norms, the present study is the first to compare the QOL adjustment of GHD patients to that of same sex siblings. A total of 140 former patients (76% of those eligible; mean age, 26 yr; n = 95 isolated GHD, n = 45 multiple pituitary hormone deficiencies; 117 males and 23 females) and 53 same sex siblings (84% participation), 18 yr and older, participated in the telephone questionnaire survey. The majority of interviews with GHD patients (78%) and siblings (87%) were conducted blind to the subject's clinical status. Comparisons between GHD patients and norms for standardized questionnaires indicated both better and worse functioning in several domains. In contrast, very limited differences were detected between GHD cases and same sex siblings. Isolated GHD patients were functioning better than those with multiple pituitary hormone deficiencies, but the effect sizes of these differences in most areas were relatively small. Adult height and degree of growth over the course of GH therapy were generally unrelated to QOL outcomes. Findings from the present study underscore the importance of selecting unbiased control/comparison groups in evaluating psychological outcomes among GHD adults. 相似文献
180.
L Rao DP Jones LH Nguyen SA McMahan RR Burgess 《Canadian Metallurgical Quarterly》1996,241(2):173-179
The pathogenic Neisseria have exploited the processes of horizontal DNA transfer and genetic recombination as mechanisms for the generation of extensive protein variation and modulation of gene expression. Localized recombinations have been well documented in members of multigene families as have alterations in short repetitive sequences. Here we report an analysis of the chromosomal structure of a defined lineage of Neisseria gonorrhoeae strain MSl1 pilin variants. This study reveals the occurrence of large rearrangements, including the amplification of a 26 kb region and an inversion involving more than a third of the chromosome. Additionally, a restriction site polymorphism that correlates with pilin expression has been observed. These findings highlight the flexibility of the gonococcal genome. 相似文献