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71.
The hypothalamo-pituitary-adrenal (HPA) axis is modulated by sex hormones. Few data exist on the relation between acute estrogen deficit and HPA axis response to corticotropin-releasing hormone (CRH). The effects of a sudden drop in estradiol levels on basal and CRH-stimulated levels of ACTH, cortisol, testosterone, androstenedione and 17-hydroxyprogesterone (17-OHP) were assessed in nine premenopausal women (44-48 years of age), before and after ovariectomy. The CRH test was performed before and 8 days after ovariectomy. A significant reduction in ACTH and adrenal steroids but not in cortisol response to CRH was observed after ovariectomy. The ratio of deltamax androstenedione/17-OHP after CRH stimulation was substantially the same before and after ovariectomy, whereas deltamax 17-OHP/cortisol was significantly lower in ovariectomized women showing increased 21- and 11beta-hydroxylase activity. The results show that the acute estrogen deficit induces changes in the HPA axis characterized by reduced stimulated secretion of ACTH and steroids but normal stimulated cortisol production. 相似文献
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73.
To detect a long-term mean shift of an autocorrelated process, traditional Process Control (SPC) techniques can be applied to monitor a process with Automatic Process Control (APC) or Engineering Process Control (EPC). In this paper, we investigate the relationships between the run-length performance, the mean-shift pattern, and the autocorrelation structure of the original process. For both monitoring the output and monitoring the control action of the APC-controlled process, we study how the mean-shift pattern affects the run-length distribution of the monitoring process. We compare the performance of the two monitoring approaches and make recommendations for various autocorrelated processes. We find that one can indicate the average run-length performance of an automatic-controlled process by examining the mean-shift pattern of the monitoring process. 相似文献
74.
Spontaneous Ni2+ entry (leak), measured as fluorescence quench in fura-2-loaded HL-60 cells at the excitation wavelength of 360 nm, was strongly inhibited by tetrandrine (TET, 100 microM), a Ca2+ antagonist of Chinese herbal origin. Exposure of the cells for 5 min to saponins from Quillaja saponaria (QS, 30 microg/ml), surfactants well known to permeabilize the plasma membrane by complexing with cholesterol, promoted Ni2+ entry without causing fura-2 leak-out. Unexpectedly, TET caused an immediate (within 2.5 min) augmentation of QS-promoted Ni2+ entry; and a 5-min treatment with both TET and QS resulted not only in an enhanced Ni2+ entry, but also a fura-2 leak-out. Ginseng saponins (100 microg/ml) alone or together with TET did not cause such a permeabilization. Permeabilization induced by 1-3 microM digitonin, another cholesterol-complexing glycoside, could not be enhanced by TET. TET did not affect permeabilization induced by Triton X-100 (0.01%), a detergent which non-specifically disrupts the hydrophobic interaction at the plasma membrane. TET also did not enhance Ni2+ entry triggered by ionomycin (0.35 microM) or SK&F 96365 (20 microM). Further, it did not augment Ni2+ entry when the plasma membrane fluidity was modulated by changes of temperature (27-47 degrees C) or treatment with 5% ethanol. This QS-promoted Ni2+ entry could not be amplified by other lipophilic Ca2+ antagonists, such as diltiazem (100 microM) and verapamil (100 microM). The results hence indicate that TET enhanced Ni2+ entry (or permeabilization) elicited by QS treatment, but not other perturbations of the plasma membrane. We suggest that pore formation at the plasma membrane, a consequence of QS-cholesterol interaction, can be specifically enhanced by TET. Also, a comparative study of the effects of TET and its very close analogues, hernandezine and berbamine, reveals that the methoxyl group at the R2 position of TET appears to be crucial in enhancing QS-promoted Ni2+ entry. 相似文献
75.
V(D)J recombination generates diversity in the immune system through the lymphoid-specific assembly of multiple gene segments into functional immunoglobulin and T-cell receptor genes. The first step in V(D)J recombination is cleavage of DNA at recombination signal sequences. Cleavage produces a blunt DNA end on each signal sequence and a hairpin end on adjacent coding gene segments, and can be reproduced in vitro by using purified RAG and RAG2 proteins. The later steps involve processing and joining of the cleaved DNA ends, and until now have been studied only in cells. Here we reconstitute the complete V(D)J recombination reaction in a cell-free system. We find that the RAG proteins are not only involved in cleavage, but are also needed in the later steps for efficient joining of coding ends. Joining is largely directed by short pieces of identical sequence in the coding flanks, but addition of human DNA ligase I results in greater diversity. Coding junctions contain short deletions as well as additions complementary to a coding flank (P nucleotides). Addition of non-templated nucleotides into coding junctions is mediated by terminal deoxyribonucleotidyl transferase. The cell-free reaction can therefore reproduce the complete set of processing events that occur in cells. 相似文献
76.
Smaller individual series on the outcome of laparoscopic hernioplasty techniques have been reported. This study reports on the complications of 3,229 laparoscopic hernia repairs performed by the authors in 2,559 patients. The TAPP (transabdominal preperitoneal) technique was the most frequently performed: 1,944 (60%). The totally preperitoneal technique was performed 578 (18%) times. The IPOM (intraperitoneal onlay mesh) repair was performed 345 (11%) times. The plug-and-patch technique was used 286 (9%) times and simple closure of the hernia defect without mesh was used in 76 (2%) repairs. Overall, there were 336 (10%) complications: 17 (0.5%) major and 265 (8%) minor. There were 54 (1.6%) recurrences, with a mean follow-up of 22 months. The TAPP technique had 19 (1%) recurrences and 141 (7%) complications. There were four bowel obstructions in this subgroup from herniation of small bowel through the peritoneal closure and trocar sites. The totally preperitoneal technique had no recurrence and 60 (10%) complications. The IPOM group had 7 (2%) recurrences and 47 (14%) complications. The plug-and-patch technique had 26 (9%) recurrences and 24 (8%) complications. The simple closure of the internal ring had 2 (3%) recurrences and 10 (13%) complications. Laparoscopic hernioplasty is not without complications. Laparoscopic hernioplasty is not without complications. Training, experience, and attention to technique will prevent some of these complications. 相似文献
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78.
TT McMahon J Devulapally KM Rosheim JL Putz M Moore S White 《Canadian Metallurgical Quarterly》1997,68(4):215-224
BACKGROUND: This study was performed to explore the epidemiology and visual outcomes of major anterior segment trauma cases referred to the Contact Lens Service (CLS) in a large, urban, eye trauma center at a university hospital. METHODS: All eye trauma patients seen on the CLS at The University of Illinois in Chicago for a 2-year period were identified (n = 122). A search of all eye trauma cases seen at UIC (n = 2279) during the same period yielded 757 cases with the same diagnostic codes. RESULTS: CLS cases represent 16.1% of cases with similar diagnoses and 5.35% of all cases seen during the period of study. Cases were predominantly young men (mean age, 28 years). The mean age for CLS cases (mean age, 17 years) was significantly younger. Best-corrected visual acuity was 20/100 or better in 75% of cases with a contact lens and in 68% of cases with a spectacle lens; 82% of CLS cases had iris damage versus 14.5% of non-CLS cases; 73% of CLS cases were aphakic; 105 CLS cases were given contact lenses. Mean follow-up time was 24 months. Mean wearing time was 11 hours/day. On interview, 35 of 79 cases (44%) continued to wear lenses. CONCLUSIONS: Cases referred to the CLS tended to be young men with unilateral injuries-predominantly open globes-with resultant aphakia and iris damage. Good visual acuity was achieved in most cases. Long-term success wearing contact lenses for this population was poor, suggesting that alternatives to contact lens wear should be more actively considered. 相似文献
79.
Cover Picture: Time‐Dependent Diaryl Ether Inhibitors of InhA: Structure–Activity Relationship Studies of Enzyme Inhibition,Antibacterial Activity,and in vivo Efficacy (ChemMedChem 4/2014) 下载免费PDF全文
80.