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51.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
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
52.
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
53.
Albrecht BK Harmange JC Bauer D Berry L Bode C Boezio AA Chen A Choquette D Dussault I Fridrich C Hirai S Hoffman D Larrow JF Kaplan-Lefko P Lin J Lohman J Long AM Moriguchi J O'Connor A Potashman MH Reese M Rex K Siegmund A Shah K Shimanovich R Springer SK Teffera Y Yang Y Zhang Y Bellon SF 《Journal of medicinal chemistry》2008,51(10):2879-2882
Tumorigenesis is a multistep process in which oncogenes play a key role in tumor formation, growth, and maintenance. MET was discovered as an oncogene that is activated by its ligand, hepatocyte growth factor. Deregulated signaling in the c-Met pathway has been observed in multiple tumor types. Herein we report the discovery of potent and selective triazolopyridazine small molecules that inhibit c-Met activity. 相似文献
54.
Homologous recombination in the fission yeast Schizosaccharomyces pombe: different requirements for the rhp51+, rhp54+ and rad22+ genes 总被引:6,自引:0,他引:6
D. F. R. Muris Kees Vreeken Henning Schmidt Kai Ostermann Beate Clever Paul H. M. Lohman A. Pastink 《Current genetics》1997,31(3):248-254
The Schizosaccharomyces pombe rhp51
+
, rad22
+
and rhp54
+
genes are homologous to RAD51, RAD52 and RAD54 respectively, which are indispensable in the recombinational repair of double-strand breaks (DSBs) in Saccharomyces cerevisiae. The rhp51Δ and rhp54Δ strains are extremely sensitive to ionizing radiation; the rad22Δ mutant turned out to be much less sensitive. Homologous recombination in these mutants was studied by targeted integration
at the leu1-32 locus. These experiments revealed that rhp51Δ and rhp54Δ are equally impaired in the integration of plasmid molecules (15-fold reduction), while integration in the rad22Δ mutant is only reduced by a factor of two. Blot-analysis demonstrated that the majority of the leu+ transformants of the wild-type and rad22Δ strains have integrated one or more copies of the vector. Gene conversion events were observed in less than 10% of the transformants.
Interestingly, the relative contribution of gene conversion events is much higher in a rhp51Δ and a rhp54Δ background. Meiotic recombination is hardly affected in the rad22Δ mutant. The rhp51Δ and rhp54Δ strains also show minor deficiencies in this type of recombination. The viability of spores is 46% in the rad22Δ strain and 27% in the rhp54Δ strain, as compared with wild-type cells. However, in the rhp51Δ mutant the spore viability is only 1.7%, suggesting an essential role for Rhp51 in meiosis. The function of Rhp51 and Rhp54
in damage repair and recombination resembles the role of Rad51 and Rad54 in S. cerevisiae. Compared with Rad52 from S. cerevisiae, Rad22 has a much less prominent role in the recombinational repair pathway in S. pombe.
Received: 20 July 1996 相似文献
55.
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
56.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
57.
Postbiopsy renal transplant arteriovenous fistulas: color Doppler US characteristics 总被引:3,自引:0,他引:3
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US. 相似文献
58.
Peripheral polyneuropathy is the most frequent complication of diabetic mellitus. In spite of many clinical trials of different specific interventions for diabetic polyneuropathy, intensive glycemic control remains the only effective specific therapy currently available for this troublesome complication. This systematic overview reports the status of current clinical trials in diabetic polyneuropathy with an emphasis on those interventions directed towards specific pathophysiological derangements. A discussion of clinical trials of agents directed towards relieving painful symptoms of diabetic polyneuropathy concludes this overview. 相似文献
59.
60.
A A van Loon R H Groenendijk G P van der Schans P H Lohman R A Baan 《International journal of radiation biology》1991,59(3):651-660
The alkaline elution technique for the detection of DNA damage has been adapted to allow application on unlabelled blood cells. Both the induction and subsequent repair have been studied of two classes of DNA damage, viz, single-strand breaks and base damage recognized by the gamma-endonuclease activity in a cell-free extract of Micrococcus luteus bacteria. The high sensitivity of the assay permitted the measurement of induction and repair of base damage after in vitro exposure of full blood under aerobic conditions to biologically relevant doses of gamma-rays (1.5-4.5 Gy). After a radiation dose of 3 Gy about 50% of the base damage was removed within 1.5 h of repair. Base damage could still be detected at 24 h after exposure to 15 Gy. 相似文献