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The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
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Natural killer (NK) cells have been suggested to play a protective role in HIV disease progression. One potent effector mechanism of NK cells is antibody-dependent cellular cytotoxicity (ADCC) mediated by antiviral antibodies binding to the FcγRIIIa receptor (CD16) on NK cells. We investigated NK cell-mediated ADCC function and the presence of ADCC antibodies in plasma from 20 HIV-1-infected patients and 10 healthy donors. The HIV-positive patients were divided into two groups: six who controlled viremia for at least 8 y without treatment (controllers), and 14 who were persistently viremic and not currently on treatment. Plasma from both patient groups induced NK cell IFN-γ expression and degranulation in response to HIV-1 envelope (Env) gp140-protein-coated cells. Patient antibodies mediating ADCC were largely directed towards the Env V3 loop, as identified by a gp140 protein lacking the V3 loop. Interestingly, in two controllers ADCC-mediating antibodies were more broadly directed to other parts of Env. A high viral load in patients correlated with decreased ADCC-mediated cytolysis of gp140-protein-coated target cells. NK cells from both infected patients and healthy donors degranulated efficiently in the presence of antibody-coated HIV-1-infected Jurkat cells. In conclusion, the character of ADCC-mediating antibodies differed in some controllers compared to viremic patients. NK cell ADCC activity is not compromised in HIV-infected patients.  相似文献   
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AJ Unwin  BL Smith  RL Allum  G Singer  JMR Burwell   《The Knee》1995,2(4):233-234
We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed using pain scores and the amount of supplementary analgesia required. The results demonstrate no benefit in delay in tourniquet deflation.  相似文献   
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The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
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Forty subjects served in a study investigating the characteristics of experimental pain measures. Subjects indicated when their pain threshold and tolerance levels had been reached with each of three Stressors: cold, pressure, and electrical shock. Using the multitrait-multimethod matrix procedure, the measures of threshold and tolerance were found to show both generality and discriminant validity across Stressors. Threshold judgements, which emphasize discrimination of nociceptive quality, and tolerance decisions, which indicate an unwillingness to receive more intense stimuli, are not equivalent measures of responsiveness. Both should be obtained in studies involving experimental pain. Stressors, while related, are also not equivalent. Minimum method variance was associated with the discomfort produced by electrical pulse trains.  相似文献   
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