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排序方式: 共有1763条查询结果,搜索用时 31 毫秒
11.
R. Gamzu L. Yogev PhD A. Botchan A. Amit J. B. Lessing D. Lichtenberg G. Paz and H. Yavetz 《Andrologia》1997,29(1):17-21
Summary. The study was conducted to evaluate the diverse effect and clinical significance of TEST yolk buffer treatment on sperm samples of 128 infertile men. Sperm samples were incubated with TEST yolk buffer and control medium (Ham's F-10) at room temperature for 2 h. The hemizona indices (mean ± SE) of the TEST yolk buffer and medium-treated sperm samples were 29 ± 2.3% and 22 ± 1.6%, respectively. Inspection of the individual response of each sperm sample to TEST yolk buffer revealed that 63 samples (49%) improved (double the interassay variation = 28%) their binding to zona pellucida, 36 (28%) remained unchanged, whereas the binding capacity of 29 samples (23%) decreased. Furthermore, TEST yolk buffer treatment of 24 samples (19%) resulted in an increased binding beyond the hemizona index threshold set up at 23%. This level was previously shown to be the cut-off point between fertile and infertile sperm samples. It was concluded that when applied to an unselected group of infertile men, TEST yolk buffer significantly increased sperm binding capacity to the zona pellucida. However, only 19% of the sperm samples showed improvement with clinical significance. The other sperm samples may have improved, remained unchanged or even deteriorated independently on basic sperm variables. Thus, the effect of TEST yolk buffer treatment on sperm binding should be tested prior to its clinical use to avoid possible damage to certain sperm samples. 相似文献
12.
目的:提高对小儿早期睾丸卵黄囊瘤的诊断与治疗水平。方法:回顾性分析12例小儿早期睾丸卵黄囊瘤的病例资料。结果:12例患者术前行阴囊B超示睾丸增大,内部回声不均匀,7例可见睾丸内积液改变;甲胎蛋白(AFP)值均明显升高。12例均行根治性睾丸切除术,术后行病理检查确诊。术前、术后均未行化疗,9例随诊5年未见复发,2002年就诊的3例目前未见复发症状。结论:小儿早期睾丸卵黄囊瘤可根据相关检查结果,结合病理检查确诊。治疗方法为行根治性睾丸切除,可不作化疗,预后较好。 相似文献
13.
目的探讨两种麻醉方法对儿童腹腔镜疝高位结扎术(lapamscopic hernia sac high ligation)应激反应的影响。方法ASAⅠ-Ⅱ级择期行腹股疝疝囊高位结扎术患儿60例,年龄6—12岁,随机分为硬膜外麻醉组(E组)和单纯气管内全麻组(G组)各30例。检测术中不同时点血浆皮质醇(Cor)、去甲肾上腺素(NE)、肾上腺素(E)、促肾上腺皮质激素(ACTH)浓度并观察平均动脉压(MAP)和心率(HR)的变化。结果E组各时点Cor、NE、E、ACHT浓度无明显变化(P〉0.05),G组气腹后上述各指标较气腹前明显增高(P〈0.05)且显著高于E组同时点(P〈0.05)(见表2);E组气腹后平均动脉压及心率变化无统计学意义(P〉0.05),而G组的则显著升高(P〈0.05);两组患儿气腹10min后PaC02均显著增加(P〈0.05),停气腹后渐恢复至正常,血PH值则变化不明显。结论硬膜外麻醉复合基础麻醉相对于单纯气管内全麻更能有效抑制儿童腹股疝疝囊高位结扎术的应激反应。 相似文献
14.
小儿腹腔镜下疝囊高位结扎术的麻醉处理 总被引:1,自引:1,他引:0
目的探讨小儿腹腔镜下疝囊高位结扎术的麻醉处理方法和安全性。方法本组80例腹腔镜下疝囊高位结扎术患儿,ASAⅠ~Ⅱ级,以气管全麻下行术式,入室后连续监测HR、MAP、SpO2、气道峰压(PIP)、PETCO2及体温,并分别记录术前、气腹后5min、气腹后10min、放气后10min的各项监测指标。结果所有患儿麻醉均满意,无一例出现麻醉意外、并发症,CO2气腹后10、20min HR、MAP、PETCO2、PIP显著升高(p<0.05,p<0.01),SpO2无显著变化,放气后10min各项指标与术前相比差异无显著意义。结论面对小儿特殊的解剖、生理和CO2气腹对生理产生的影响,做好术前准备,选择正确的麻醉方法和合适的麻醉药物,维持稳定的循环,小儿可安全实施腹腔镜疝囊高位结扎手术。 相似文献
15.
一氧化氮与胚胎异常发育的相关性研究 总被引:3,自引:0,他引:3
为了解开一氧化氮(NO)是否与畸胎发生有关这一谜团和进一步阐明砷致畸作用机理,本实验应用诱生型NO合成酶(iNOS)组织化学、扫描电镜(SEM)及体内致畸试验等方法研究了砷对小鼠卵黄囊胎盘(YSP)和胚胎发育的影响。结果表明YSP细胞iNOS表达与砷浓度之间存在明显的剂量—反应关系(P<0.05);SEM观察可见YSP内皮层和间皮层细胞受损;光镜下可见YSP变小、萎缩和微血管分化不良;随着染毒剂量的升高,畸胎率和死胎率亦逐步增加,最高分别达到56.8%和24.7%;畸胎的主要表现是神经管未闭,心包积液和体位异常等。研究结果率先提示过量NO与畸胎发生及致畸机理关系密切;推荐在致畸研究中iNOS可作为一种有效的生物标志物。 相似文献
16.
Summary Shortly after subcutaneous or intraperitoneal injection of nontoxic quantities of trypan blue into laying Japanese quails, red fluorescent yolk granules appear in the peripheral ooplasm of their oocytes at the end of the lampbrush stage or subsequently. Later a red fluorescence can be observed in the apical cytoplasm of the granulosa cells. The results obtained by this method confirm our previous results (Callebaut 1974) obtained by autoradiography after 3H-leucine administration and furnish interesting additional data. The trypan blue-induced fluorescence method gives a good indication of the permeability of the oocytal cortex and its derivative the germinal disc. The avian yolk which is, or has been peripherally assembled (primordial, true white and yellow yolk) can be characteristically labelled by the administration of trypan blue. The injection of higher, still nontoxic quantities of trypan blue has a prolonged retarding effect and permits the marking of a broader part of the germinal disc or eventually of the blastoderm which develops from it. 相似文献
17.
M. Vandenbranden J.L. de Coen R. Jeener L. Kanarek J.M. Ruyschaert 《Molecular immunology》1981,18(7):621-631
Interactions between rabbit-γ-immunoglobulins and model membranes (lipid monalayers, planar lipid bilayers, liposomes) have been investigated. No significant interaction was observed with immunoglobulins. However, immunoglobulins dialysed first vs aqueous buffer having pH 2 or 3 and then dialysed against pH 7 buffer presumably adopt a new conformation which allows their bindings to model membranes. This binding is hydrophobic and the immunoglobulin region interacting with the lipid acyl chains is probably located in the heavy chain, as suggested by labelling in this region by a photosensitive probe previously incorporated into the lipid hydrophobic core. Cleavage at the hinge region by papain or pepsin, or heating above 38°C, induces the loss of the hydrophobic conformation responsible for hydrophobic bindings. The binding capacity of immunoglobulins heated above 38°C is restored after momentary dialysis at pH 2. The possible existence of two Ig isomers is discussed in relation to the mechanism of γ-immunoglobulin passage through the endoplasmic membrane and fixation into the plasma membrane. 相似文献
18.
Ulug U Jozwiak EA Mesut A Berksoy MM Bahceci M 《Human reproduction (Oxford, England)》2004,19(2):360-364
BACKGROUND: The purpose of this study was to determine the rate of spontaneous gestational sac loss during the first trimester in women achieving multiple pregnancies by ICSI. METHODS: A retrospective analysis was performed of 1448 consecutive multiple pregnancies conceived by ICSI. RESULTS: Of the cohort of 1448 pregnancies, twin gestations constituted 59.6% (864), triplets 30.2% (438) and quadruplets 10.0% (146). During the first trimester, 69 (4.7%) patients miscarried, while 179 (12.3%) continued their pregnancies and had fewer gestational sacs at the end of the first trimester than at the beginning. The overall loss rate of any gestational sac during the first trimester in these multiple pregnancies was 10.1%. There was a significant difference in the frequency of spontaneous reduction to twin or singleton pregnancies in the first trimester between women carrying triplets (11.7%) and those carrying quadruplets (3.5%) [P = 0.004; odds ratio (OR) 3.5; 95% confidence interval (CI) 1.3-9.1]. The frequency of gestational sac loss was significantly greater among women >35 years old (20.9%) than in women less than 35 years old (15.9%) (P = 0.03; OR 1.4; 95% CI 1.0-1.9). CONCLUSION: In multiple pregnancies there is a significant risk of spontaneous loss of any embryo during the first trimester. These findings should be considered prior to any decision about selective embryo reduction. 相似文献
19.
Anders Larsson David Carlander Martin Wilhelmsson 《Food and Agricultural Immunology》1998,10(1):29-36
Chicken antibodies offer many advantages over the traditional mammalian ones. A laying hen produces large amounts of yolk antibodies and the use of yolk antibodies eliminates the painful procedure of collecting blood from the animal. Thus, the use of chicken antibodies will reduce both the number of animals required to produce antibodies and also animal distress. Chicken antibodies also have several biochemical advantages compared to mammalian antibodies: they often increase the signal and reduce interference in many assays. However, the species chosen for antibody production have usually been mammals. This is probably due to tradition, but also to limited knowledge about the production of chicken antibodies. We studied the immune response in the chicken using small amounts of mammalian antigen, and show that a good immune response can be obtained with 0.1–1.0 μg of bovine serum albumin. 相似文献
20.
Extraembryonic rhythmic motor activity in higher vertebrates, along with the intrinsic motor activity of the embryo, is important
for the normal development of the embryo. This can have different natures in different classes of amniotes (i.e., motor activities
of the amnion, yolk sac, and uterus), but these have similar functional importance. This activity changes reproducibly during
the process of embryogenesis, providing the optimum conditions for normal embryo development. During embryogenesis, a system
for controlling extraembryonic rhythmic motor activity is also formed. There is a trend for the regulation of this activity
to become more complex in mammals as compared with birds. Reptiles have received little study from this point of view. In
addition to regular changes in extraembryonic rhythmic motor activity during embryogenesis which depend on the developmental
stage of the embryo, motor activity can also change in response to changes in a number of environmental factors (for example,
temperature and the gas composition of the air). This demonstrates the possible involvement of embryo-associated extraembryonic
motor activity in adapting the embryo to changing environmental conditions and maintaining homeostasis for the development
of the embryo itself.
Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 84, No. 10, pp. 961–968, October, 1998. 相似文献