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101.
Insemination with donor spermatozoa is an integral part of infertility treatment. For the last 3 years in our unit, intrauterine insemination with donor spermatozoa (IUID) has been used in preference to vaginal insemination. In this retrospective study, patients were offered an initial course of five single intrauterine inseminations with cryopreserved donor spermatozoa and treatment was then reviewed. A total of 389 patients received 1465 inseminations. In all, 1119 cycles were monitored using luteinizing hormone serum analyses and 346 cycles using the urine home test kits. The clinical pregnancy rate per insemination for the cycles monitored by the serum assay was 18.0% (202/1119) compared with the urine cycles (13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles respectively). The viable clinical pregnancy rate was significantly higher (P <03) for the serum cycles than for the cycles using the urinary monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles monitored by serum assay had a significantly higher cumulative viable clinical pregnancy rate (P <0001) of 70.2% after nine inseminations compared with the urine monitored cycles of 54.8%. The majority of patients opted for the serum cycles, with a minority self-selecting the urine cycles mainly for travelling convenience. The explanation for the significant differences between the viable clinical pregnancy rates per insemination and the cumulative viable clinical pregnancy rates may be due to the sensitivity of the urine home test kit or the patients' interpretation of the result.   相似文献   
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Inhaled beta-agonists can produce bronchodilatation and reduce airway hyperreactivity in patients with asthma. Using these two measures, we compared inhaled bitolterol (three puffs, 1110 micrograms), albuterol (two puffs, 180 micrograms), and placebo administered by metered-dose inhaler in a blinded, crossover study of 40 subjects with chronic asthma. On each study day, subjects underwent histamine challenges at 1 1/2 hours before, and 1/2, 2, 4, 6, and 8 hours after inhaling one of the three test-drug treatments. Both drugs produced significant bronchodilatation at 30 minutes through 4 hours and significant effects on airway reactivity at 30 minutes through 2 hours (p less than 0.05). Bitolterol also produced small but significant bronchodilator effects at 6 hours and effects on airway reactivity at 4 hours (p less than 0.05). Effects of bitolterol on airway reactivity diminished significantly more slowly than effects of albuterol in subjects with baseline provocative concentration causing a 20% fall in FEV1 greater than or equal to 1.0 mg/ml of histamine (half-life of biologic effect 1.37 versus 0.92 hours; p less than 0.05) but not in subjects with baseline provocative concentration causing a 20% fall in FEV1 less than or equal to 1.0 mg/ml (half-life of biologic effect of 1.01 versus 1.00 hours; p greater than 0.05).  相似文献   
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Toll-like receptor 6 (TLR6) is one of a series of highly conserved innate immune receptors. We resequenced TLR6 in DNA samples from 24 African Americans, 23 European Americans, and 24 Hispanic Americans, identifying 53 SNPs, 22 with an allele frequency >5%. Significant differences in SNP frequencies among the three populations were noted. In all, 11 SNPs caused amino-acid changes, including one with a frequency >5% in all three populations. Utilizing this SNP (Ser249Pro), we performed exploratory nested case-control disease-association studies, including one involving 56 African Americans with asthma and 93 African American controls. The minor allele of this SNP was associated with decreased risk for asthma (odds ratio 0.38, 95% CI 0.16-0.87, P=0.01), an effect consistent with the known biology of the toll-like receptors. Although replication of this finding in other, larger samples is needed, variation in TLR6 may have relevance to the pathogenesis of immunologically mediated diseases.  相似文献   
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The amount of lysine in collagen is only 3 or 4% of total aminoacids, but it has an important function in the constitution of the cross-links between the molecules to built the fibrils and the fibers of collagen. For this function, some lysine molecules must be hydroxylated and other oxidized to aldehyde compounds. Some deficits in these metabolic pathways are responsible for heritable diseases of the connectivite tissue as types IV and IX of the Ehlers-Danlos syndrome, lathyrism, the Menkes kinky hair syndrome, Cutis-Laxa or the type II of osteogenesis imperfecta. The contribution to fibrosis is also discussed.  相似文献   
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目的:观察在蛋白激酶C(PKC)激动剂TPPB促进可溶性淀粉样前体蛋白(sAPPα)释放过程中参与的信号转导通路。方法:以1 μmol/L的TPPB作用于PC12细胞3 h,同时加入信号转导通路的抑制剂,Western印迹法检测上清液内sAPPα的含量和细胞外信号调节激酶(p42/44MAPK)及磷酸化的p42/44MAPK的表达。结果:1 μmol/L的TPPB作用于PC12细胞3 h可以显著增加上清液内sAPPα的含量,细胞外信号调节激酶抑制剂U0126、c-Jun氨基末端激酶抑制剂SP600125和蛋白酪氨酸激酶抑制剂genistein可以部分消除此作用;而p38MAPK抑制剂SB203580对sAPPα的含量无显著影响。1 μmol/L的TPPB可以使磷酸化的p42/44MAPK表达增加,而对总的p42/44MAPK无显著影响。结论:细胞外信号调节激酶、c-Jun氨基末端激酶和蛋白酪氨酸激酶可能参与TPPB促进sAPPα生成的过程。  相似文献   
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不同栓塞范围的急性肺栓塞动物模型建立   总被引:2,自引:1,他引:2       下载免费PDF全文
目的:制备不同栓塞范围的急性肺栓塞动物模型,研究血流动力学变化与肺栓塞范围的相关性。方法:经导管注入犬自体血栓选择性栓塞肺动脉,通过控制注入血栓数量、速度,分别建立不同栓塞范围的急性肺栓塞动物模型;比较栓前、栓后15 min、30 min、1 h及2 h血流动力学指标变化,同时观察心脏超声影像学变化。结果:自体血栓均按要求阻塞相应肺动脉,肺栓塞形成后心输出量下降,肺动脉压力及肺毛细血管楔压显著增高,并在0.5 -1 h达到峰值,各血流动力学指标随肺栓塞范围增大而变化更显著。结论:此急性肺栓塞动物模型制作方法确切可行。  相似文献   
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