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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   
3.
Experiments on mice of nine strains with different H-2 genotypes showed that a predisposition to anaphylaxis at the stage of formation of IgG1 and IgE antibodies and sensitivity of the skin to passive anaphylaxis and to histamine are independent characters, interaction between which and with other factors form the overall predisposition to immediate allergy.Allergologic Research Laboratory, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 318–320, March, 1977.  相似文献   
4.
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   
5.
The antiphosphodiesterase preparation 1-methyl-3-isobutylxanthine (MIBX) inhibited anaphylactic reactionsin vitro andin vivo: It inhibited the anaphylactic liberation of histamine from isolated rat mast cells, the anaphylactic contraction of the isolated guinea pig trachea, the passive cutaneous anaphylactic reaction (PCAR) in mice, and anaphylactic bronchospasm (AB) in guinea pigs. The MIBX inhibited the anaphylactic reaction of the trachea, PCAR, and AB to a greater degree than the corresponding reactions induced by histamine.Allergologic Scientific-Research Laboratory, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 443–446, April, 1977.  相似文献   
6.
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   
7.
Flow cytofluorimetry and statmokinetic method were used to study the circadian rhythm of bone marrow proliferation in Pliss' lymphosarcoma-bearing and intact rats. These data were compared to those obtained in the study of the mitotic activity of the bone marrow in cancer patients. It was found that, already at early stage, tumor affected the circadian rhythm of bone marrow proliferation, reducing the amplitude of oscillations. A model simulating formation of the circadian rhythm of the bone marrow was suggested basing on the possibility to arrest cells at the end of G1 phase. The rate of transition of G1 cells to S phase was determined not only by endogenous "set-points" of the rhythm which formed the basic wave of proliferation but also by conditions of animal upkeep.  相似文献   
8.
BACKGROUND AND PURPOSE: Complete stricture of the ureteropelvic junction (UPJ), ureter, or both represents a secondary upper tract obstruction and is a challenge for surgical management. The endourologic repair of these complete strictures remains controversial because of the many unsatisfactory results in the literature. The aim of this study was to achieve recanalization of the ureter or the UPJ using endourologic techniques to prove durable success of this technique. PATIENTS AND METHODS: We present data on the 21 patients with complete UPJ or ureteral strictures treated over 5-year period. The length of the obliterated portion of the ureter or UPJ ranged from 0.3 to 1.7 cm. The stricture was at the UPJ level in 12 patients (57%), in the upper ureter in 3, and in the lower ureter in 4. The technique was a combined approach, with antegrade introduction of the guidewire and retrograde cold-knife incision in the majority of the cases. In five cases, the incision was carried out in the reverse direction with a guidewire introduced retrograde up to the stricture level. An originally designed 6F to 7F polyethylene double-J stent with a movable 12F to 16F silicon sheath or percutaneous tube was placed at the completion of the procedure. RESULTS: The follow-up period ranged from 6 to 48 months. Recanalization was achieved in 17 patients (81%), of whom 14 became symptom free. Other surgical outcomes necessitated open surgical intervention (pyeloplasty, nephrectomy) in two patients. One patient developed a clinically significant recurrent urinary tract infection and deterioration of kidney function. Thus, the overall success rate of the endourologic management of the complete UPJ and ureteral strictures was 67% in our series. CONCLUSION: Endourologic management with retrograde or antegrade pyeloureterotomy can be successful in patients with short (up to 1.0-cm) obliterative strictures who are without extensive hydronephrosis and with preserved renal function.  相似文献   
9.
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   
10.
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