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1.
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   
2.
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   
3.
To further evaluate the effect of 25(OH)vitamin D3 (25(OH)vit D3) on renal handling of phosphorus, fractional excretion of phosphorus (CP/CIn) and urinary excretion of cyclic AMP (UcAMP) were measured in the following groups of animals: 1) intact rats receiving intravenously 25(OH)vit D3. 2a) Parathyroidectomized (PTX) rats receiving a continuous infusion of parathyroid hormone (PTH). 2b) PTX rats undergoing continuous infusion of PTH and receiving intravenously 25(OH)vit D3. In group 1 a decrease in CP/CIn from a control value of 0.210 +/- 0.064 (kappa +/- SE) to 0.052 +/- 0.017 (P less than 0.001) during 25(OH)vit D3 infusion was associated with a corresponding decrease in UcAMP from 182 +/- 18 to 87 +/- 8 pmol/min (P less than 0.001). In group 2a an increase in CP/CIn from a control value of 0.031 +/- 0.014 to 0.365 +/- 0.017 during PTH infusion was associated with a corresponding increase in UcAMP from 76 +/- 17 to 330 +/- 51 pmol/min (P less than 0.001). In group 2b a decrease in CP/CIn from 0.365 +/- 0.017 to 0.256 +/- 0.011 (P less than 0.01) during 25(OH)vit D3 infusion was associated with a decrease in UcAMP from 356 +/- 63 to 191 +/- 33 pmol/min (P less than 0.01). These results indicate that the blunting of the phosphaturic response to PTH by 25(OH)vit D3 is associated with a decrease in UcAMP. This observation suggests that the mechanism underlying the enhanced tubular reabsorption of phosphorus is inhibition of the PTH-induced activation of adenylate cyclase in the kidney.  相似文献   
4.
急性有机磷农药中毒120例的救治   总被引:1,自引:0,他引:1  
0 引言 近年来 ,我科在救治急性有机磷农药 (organophos-phorus,OP)中毒方面 ,积累了一些经验 ,现报告如下 .1 对象和方法1 .1 对象 本组 1 2 0例符合《急诊急救学》中的诊断标准 [1 ](男 2 9例 ,女 91例 ) ,年龄 1 .5~ 70岁 ,平均 2 8.6岁 .经口中毒 99例 ,经皮肤中毒 2 1例 .轻度中毒 1 5例 ,中度中毒 42例 ,重度 (含极重度 )中毒 6 3例 . 1 996年 39例 ,1 997年 43例 ,1 998年 38例 . DDV 79例 ,乐果 2 0例 ,混合性中毒 1 0例 ,水胺磷 3例 ,氧化乐果、 391 1、 1 0 5 9、对硫磷各 2例 ,敌百虫 1例 ,药名不详 1 0例 .服毒量 >2 5 …  相似文献   
5.
Upham  BL; Kang  KS; Cho  HY; Trosko  JE 《Carcinogenesis》1997,18(1):37-42
Cell to cell communication via gap junctions is essential in the maintenance of the homeostatic balance of multicellular organisms. Aberrant intercellular gap junctional communication (GJIC) has been implicated in tumor promotion, neuropathy and teratogenesis. Oxidative stress has also been implicated in similar pathologies such as cancer. We report a potential link between oxidative stress and GJIC. Hydrogen peroxide, a known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible as indicated by the complete recovery of GJIC with the removal of H2O2 via a change of fresh media. Free radical scavengers, such as t-butyl alcohol, propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2, which indicated that the effects of H2O2 on GJIC was probably not a consequence of aqueous free radical damage. The depletion of intracellular GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of glutathione- sufficient cells with H2O2 resulted in the hyperphosphorylation of connexin43, which is the basic subunit of the hexameric gap junction protein, as determined by Western blot analysis. TPA, a well-known tumor promoter, also inhibits GJIC via hyperphosphorylation of GJIC, which is a result of protein kinase-C activation. However, H2O2 also induced hyperphosphorylation in GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism of GJIC inhibition must be different from the TPA-pathway and involves GSH.   相似文献   
6.
7.
Intelligibility scores with a modified rhyme test were obtained for normally hearing subjects and subjects with sensorineural hearing impairment using several commercial hearing aids. These hearing aids differed mainly in values of time constants of compression and of harmonic distortion during overshoots. In general, better performance was obtained for the shorter time constants of compression, but performance seemed also to be affected by the occurrence of higher levels of harmonic distortion and of peak-clipping during overshoots.  相似文献   
8.
9.
Angiogenic factors stimulate mast-cell migration   总被引:18,自引:1,他引:18  
Gruber  BL; Marchese  MJ; Kew  R 《Blood》1995,86(7):2488-2493
Mast cells accumulate at sites of angiogenesis. The factor(s) that control mast-cell recruitment at these sites have yet to be defined. We sought to determine if angiogenic factors result in mast-cell chemotaxis. In this study, we observed that platelet-derived growth factor-AB (PDGF-AB), vascular endothelial cell growth factor (VEGF), and basic fibroblast growth factor (bFGF) each cause directed migration of murine mast cells at picomolar concentrations, with a typical bell- shaped dose-response curve. Another potent angiogenic factor, platelet- derived endothelial cell growth factor (PD-ECGF), appears to promote chemokinesis of mast cells, whereas tumor necrosis factor-alpha, a weak angiogenic factor, is less robust but still functions as a mast cell chemotactic factor. Epidermal growth factor (EGF), a growth factor with minimal angiogenic properties, was ineffective as a mast cell chemotactic factor. A checkerboard analysis confirmed the directional chemotactic response of PDGF-AB, VEGF, and bFGF, while indicating the chemokinetic response induced by PD-ECGF. Cross-desensitization of growth-factor-induced directed migration was observed between PDGF-AB and bFGF, and also between PDGF-AB and PD-ECGF. Tyrosine kinase- inhibitor genistein effectively dampened the chemotactic responses, whereas pertussis toxin had no effect. In summary, our findings suggest that factors known to act on endothelial cells and stimulate neovascularization may simultaneously serve to recruit mast cells to these sites. The local accumulation of mast cells is believed to facilitate new vessel formation through complex cell:cell interactions.  相似文献   
10.
Introduction

Patients with pelvic and acetabular fractures often have considerable pain in the perioperative period. Regional anesthesia (RA) including peripheral nerve blocks and spinal analgesia may reduce pain. However, the real-world impact of these modalities on inpatient opioid consumption and outpatient opioid demand is largely unknown. The purpose of this study was to evaluate the impact of perioperative RA on inpatient opioid consumption and outpatient opioid demand.

Methods

This is a retrospective, observational review of inpatient opioid consumption and outpatient opioid demand in all patients ages 18 and older undergoing operative fixation of pelvic and acetabular fractures at a single Level, I trauma center from 7/1/2013–7/1/2018 (n = 205). Unadjusted and adjusted analyses were constructed to evaluate the impact of RA on inpatient opioid consumption and outpatient opioid demand while controlling for age, sex, race, body mass index (BMI), smoking, chronic opioid use, ASA score, injury mechanism, additional injuries, open injury, and additional inpatient surgery.

Results

Adjusted models demonstrated increases in inpatient opioid consumption in patients with RA (12.6 estimated OE’s without RA vs 16.1 OE’s with RA from 48 to 72 h post-op, p < 0.05) but no significant differences at other timepoints (17.5 estimated OE’s without RA vs 16.8 OE’s with RA from 0 to 24 h post-op, 15.3 vs 17.1 from 24 to 48 h post-op, p > 0.05). Estimated cumulative outpatient opioid demand was significantly higher in patients with RA at discharge to 90 days post-op (and 156.8 vs 207.9 OE’s to 90 days, p < 0.05) but did not differ significantly before that time (121.5 OE’s without RA vs 123.9 with RA from discharge to two weeks, 145.2 vs 177.2 OE’s to 6 weeks, p > 0.05).

Discussion

In pelvis and acetabulum fracture surgery, RA was associated with increased inpatient and outpatient opioid demand after adjusting for baseline patient and treatment characteristics. Regional anesthesia may not be beneficial for these patients.

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