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91.
A cohort of 485 couples starting their first in-vitro fertilization(IVF) attempt between January, 1989 and February, 1991 inclusive,were followed until June 1, 1992. A total of 1086 treatmentcycles were initiated (mean 2.2, range 1–6). Of these,235 (21.8%) cycles were cancelled, giving a total of 851 embryoreplacements (mean 1.7, range 1–5). After IVF treatment,189 women have either delivered or have an ongoing pregnancyin the second or third trimester. This gives a baby take-homerate of 17.4% per started cycle and 22.2% per embryo replacement.For 91 (18.6%) of the couples, the treatment was abandoned priorto completion of the three scheduled IVF attempts and 57 (11.7%)of these had no completed IVF cycles. In the group of coupleswith reduced sperm quality, the delivery rate was significantlylower than that of the other groups. A total of 193 women hadembryos cryopreserved in at least one IVF cycle; 124 of thesewomen started a frozen embryo replacement cycle and 88 had atleast one cycle with replacement of frozen/thawed embryos, resultingin 25 deliveries/ongoing pregnancies. Due to the Norwegian lawon assisted procreation 65 (33.7%) of the women have had theirfrozen embryos thawed and discarded after 12 months of storage.The cryopreservation programme, with the limitations of theNorwegian law, gives a 5.2% increase in the baby take-home ratefor women entering the IVF programme, an increase of 13.2% inthe number of ongoing pregnancies/deliveries and an 11.6% increasein number of children/viable fetuses. A total of 214 women havedelivered or have ongoing pregnancies in the second or thirdtrimester. This represents 44.1% of the 485 women accepted forIVF treatment, irrespective of whether they were treated ornot, and 50.0% of those couples who completed at least one IVFcycle.  相似文献   
92.
目的:报告股骨近端解剖型钢板治疗股骨转子间骨折的疗效。方法:应用股骨近端解剖钢板治疗19例股骨转子间骨折,评价治疗结果。结果:19例病人中4个月全部骨性愈合,髋关节屈伸活动恢复95%以上,旋转活动恢复85%,2例轻度髋内翻。结论:股骨近端解剖型钢板治疗转子间骨折具有手术简单,有效,符合生物力学要求,效果满意。  相似文献   
93.
Enhancement of the speed and sensitivity of an ELISA technique was achieved by doing it on a polystyrene microtiter plate preactivated by a simple photochemical reaction. Immobilization of Epicoccum nigrum antigen (allergenic antigen) or goat anti-rabbit IgG onto the photoactivated plates was found to occur in only 45 min with higher binding than that obtained through adsorption during the same period onto the untreated surface. Nearly 1.5-2-folds higher readings were obtained when the ELISA was carried out with the solid phase prepared on the photoactivated surface rather than on the untreated surface. Moreover, solid phases prepared on the activated surface could detect IgE (E. nigrum antibody) even at 1/50 (v/v) dilutions, whereas a solid phase prepared on the untreated surface failed to do so. Around three times higher ELISA values were obtained in the activated plate than the untreated plate when IgE was diluted to 1/5 (v/v). Such photoactivated surface could be of great importance in diagnostic tests involving the ELISA technique particularly to confirm false negative cases and for other immunoassays such as radioimmunoassay procedures.  相似文献   
94.
An energy balance of front crawl   总被引:1,自引:3,他引:1  
With the aim of computing a complete energy balance of front crawl, the energy cost per unit distance (C= v–1, where is the metabolic power and v is the speed) and the overall efficiency (o=Wtot/C, where Wtot is the mechanical work per unit distance) were calculated for subjects swimming with and without fins. In aquatic locomotion Wtot is given by the sum of: (1) Wint, the internal work, which was calculated from video analysis, (2) Wd, the work to overcome hydrodynamic resistance, which was calculated from measures of active drag, and (3) Wk, calculated from measures of Froude efficiency (F). In turn, F=Wd/(Wd+Wk) and was calculated by modelling the arm movement as that of a paddle wheel. When swimming at speeds from 1.0 to 1.4 m s–1, F is about 0.5, power to overcome water resistance (active body drag × v) and power to give water kinetic energy increase from 50 to 100 W, and internal mechanical power from 10 to 30 W. In the same range of speeds increases from 600 to 1,200 W and C from 600 to 800 J m–1. The use of fins decreases total mechanical power and C by the same amount (10–15%) so that o (overall efficiency) is the same when swimming with or without fins [0.20 (0.03)]. The values of o are higher than previously reported for the front crawl, essentially because of the larger values of Wtot calculated in this study. This is so because the contribution of Wint to Wtot was taken into account, and because F was computed by also taking into account the contribution of the legs to forward propulsion.  相似文献   
95.
Two methods for in vitro endpoint titration of poliovirus — the roller tube and the microtitration assay — were compared with each other and with the plaque assay, using secondary vervet monkey kidney cells and Vero cells as indicators. The roller tube method is the most reliable under difficult working conditions, but is otherwise cumbersome and expensive. The microtitre method is the most economical and the plaque assay the most sensitive. By suspending freshly trypsinized indicator cells with the virus dilutions before planting, it was possible to simplify the microtitre method considerably. The sensitivity of the plaque assay was improved for Vero cells by absorbing the virus onto freshly planted monolayers. The method was scaled down to a semi-micro level by using 24-well cell culture trays. The slower rate of plaque development under a low calcium overlay medium facilitated a more accurate plaque count.  相似文献   
96.
目的探讨锁定加压钛板内固定治疗桡骨远端骨折疗效。方法对2001~2006年间49例桡骨远端骨折经掌背侧联合入路锁定加压钛板内固定,钛板置于桡骨远端背侧,骨缺损严重者(20例)均置入人工骨(OsteoSet)。术后功能康复时间,6~24周,平均10.6剧。结果随访6~24个月。按Dienst功能评估标准进行评定:优40例,良7例,差2例,优良率95.9%。结论掌背侧联合入路锁定加压钛板内固定治疗移位的桡骨远端骨折疗效显著。  相似文献   
97.
The proximal and distal growth plates of the principal long bones do not contribute equally to longitudinal growth. Most forelimb elongation occurs at the shoulder and wrist, while most hindlimb growth occurs at the knee. This study examined whether insulin‐like growth factor‐I (IGF‐I), a potent growth regulator, could underlie this variation via differential receptor expression. The spatiotemporal distribution of the IGF‐I receptor (IGF‐IR) was mapped in hindlimb growth plates (overall and within regional zones) from immature mice using immunohistochemistry. Growth activity was assessed by size/morphology of the growth plate and proliferating cell nuclear antigen (PCNA) expression. Both IGF‐IR and PCNA staining declined considerably with age in the proximal femur and distal tibia (hip and ankle), but expression remained high in the more active distal femur and proximal tibia (knee) throughout growth. Growth plate size decreased with age in all sites, but the absolute and relative decline in IGF‐IR in the hips and ankles of older mice indicated a site‐specific loss of IGF‐I sensitivity in these less active regions. These results suggest that regulation of the IGF‐IR may at least partially mediate differential long bone growth, thereby providing a local mechanism for altering skeletal proportions absent modification of systemic hormone levels. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
98.
Summary To investigate the effect of hyperthyroidism on the pattern and time course of O2 uptake ( O2) following the transition from rest to exercise, six patients and six healthy subjects performed cycle exercise at an average work rate (WR) of 18 and 20 W respectively. Cardiorespiratory variables were measured breath-by-breath. The patients also performed a progressively increasing WR test (1-min increments) to the limit of tolerance. Two patients repeated the studies when euthyroid. Resting and exercise steady-state (SS) O2 (ml·kg–1·min–1) were higher in the patients than control (5.8, SD 0.9 vs 4.0, SD 0.3 and 12.1, SD 1.5 vs 10.2, SD 1.0 respectively). The increase in O2 during the first 20 s exercise (phase I) was lower in the patients (mean 89 ml·min, SD 30) compared to the control (265 ml·min–1, SD 90), while the difference in half time of the subsequent (phase 11) increase to the SS O2 (patient 26 s, SD 8; controls 17 s, SD 8) were not significant (P = 0.06). The OZ cost per WR increment ( O2/WR) in ml·min–1·–1, measured during the incremental period (mean 10.9; range 8.3–12.2), was always within two standard deviations of the normal value (10.3, SD 1). In the two patients who repeated the tests, both the increment of O2 from rest to SS during constant WR exercise and the O2/WRs during the progressive exercise were higher in the hyperthyroid state than during the euthyroid state. While both resting and exercise O2 are increased in the hyperthyroid patients, the O2 cost of a given increment of WR is within the normal range. However, a small reduction in the O2 requirement to perform exercise following treatment of the hyperthyroid state suggests a subtle change O2 cost of muscle work in this disease.  相似文献   
99.
目的探讨应用胫骨远端锁定钢板经皮微创植入治疗胫骨远端骨折的疗效。方法自2010年1月~2012年12月应用小切口植入胫骨远端锁定钢板治疗32例胫骨远端骨折,男19例,女13例,年龄13~77岁,平均39.8岁。其中开放性骨折4例,闭合性骨折28例,均为新鲜骨折。结果 29例获得随访,随访时间6~15个月,平均11.7个月。所有骨折均愈合,平均愈合时间为13.6周,均无感染、骨不连、钢板松动等并发症。按照Mazur踝关节功能评分:优19例,良8例,可2例,优良率为93.1%。结论微创钢板内固定手术创伤小,固定可靠,骨折愈合率高,符合生物学固定原则。  相似文献   
100.
一种平板流动腔重力灌流系统的力学分析   总被引:2,自引:1,他引:2  
本文分析了一种采用重力灌流的平板流动腔灌流系统,并根据实验结果确定出相应的阻力系数,获得平板流动腔剪应力、雷诺数以及入口长度与流体重力灌流高度的关系。  相似文献   
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