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61.
Intracytoplasmic sperm injection in the mouse 总被引:9,自引:0,他引:9
Ron-El R.; Liu J.; Nagy Z.; Joris H.; Van den Abbeel E.; Van Steirteghem A. 《Human reproduction (Oxford, England)》1995,10(11):2831-2834
Intracytoplasmic sperm injection (ICSI) into mouse oocytes involvesa very low survival rate. This study was designed to determinewhy ICSI frequently fails in mice. Metaphase II oocytes wereobtained from superovulated 46 week old F1 hybrid mice.Spermatozoa were retrieved from the epididymis of 1214week old F1 hybrid mice. The spiked microinjection pipette usedto inject a spermatozoon into the ooplasm had outer and innerdiameters of 10 and 8 µm respectively. The oocytes usedin the first part of the study were not activated (group 1).Some oocytes were incubated with calcium ionophore for 5 min(group 2). The injected oocytes were evaluated 6, 20, 48 and72 h after injection. A total of 143 eggs in each group underwentICSI. In group 1, sperm heads escaped into the perivitellinespace. In all, 63 (47%) of the remaining oocytes were damagedduring the injection or had degenerated by the first evaluation.The survival rate was 53%, but fertilization did not occur.In group 2, 31 oocytes (22%) were damaged during microinjectionor soon degenerated. Two oocytes underwent accidental subzonalinsemination. Six oocytes were fertilized (4.2%) among the 78%of survivors. After injection, the sperm tail was found in thecytoplasm (27 and 31% in groups 1 and 2 respectively), the perivitellinespace (45% in both groups) or protruding through the zona pellucida(28 and 23% respectively). More oocytes degenerated when thetail remained in the cytoplasm, i.e. 78% in group 1 and 36%in group 2. 相似文献
62.
目的:观察青年和老年期大鼠下丘脑弓状核阿黑皮素原mRNA(POMC mRNA)的表达水平。方法应用原位杂交技术显示POMCmRNA和用计算机图像分析观察杂交信号的强弱及阳性细胞的面积,结果:与青年组相比,老年组下丘脑弓状核及其附近区域POMCmRNA阳性神经元的灰度下降,POMCmRNA阳性神经元的数目无明显变化,结论:老年期POMCmRNA阳性神经元相应的mRNA表达水平下降可能是下丘脑的POMC基因衍生肽表达水平下降的原因之一。 相似文献
63.
电视胸腔镜在胸心外科临床应用76例报告 总被引:1,自引:0,他引:1
目的 总结分析 76例电视胸腔镜胸心外科手术。 方法 手术方法包括 :动脉导管钳闭 ;纵隔肿瘤 ,胸交感神经切除 ;肺、胸膜 ,纵隔淋巴结活检 ;肺大泡、自发性气胸治疗 ;外伤性血胸 ,自发性血胸 ,不明原因胸腔积液探查 ;胸膜固定术 ;心包开窗引流 ;包裹性脓肿清除。 结果 电视胸腔镜 PDA钳闭病例 ,彩色超声心动图复查均无残余分流 ,术后最长已随访 2年 ,未发现再通现象。纵隔肿瘤成功地在电视胸腔镜下摘除。原发性长 QT综合征左 T2 、T3交感神经节广泛切除后 ,术后即刻 QT间期即从 0 .6 0 s缩短为 0 .42 s,术后再未出现室性心动过速和昏厥现象。重症雷诺病患者行双侧胸交感神经节切除后 ,末梢循环得到显著改善 ;自发性气胸治疗多数术后仅留置闭式引流 2~ 4天 ;纵隔淋巴结活检为准确病理诊断提供了新手段。 结论 电视胸腔镜下动脉导管钳闭等手术安全可靠、创伤小 ,值得进一步应用和完善。 相似文献
64.
电视胸腔镜解剖学肺叶切除20例 总被引:2,自引:0,他引:2
目的 探讨电视胸腔镜(VATS)辅助小切口解剖学肺叶切除术的手术式和手术指征,尤其对肺癌的手术。方法 应用VATXS辅助小切口中小学肺叶切除手术20例,手术通过胸前外侧7cm左右辅助小切口,VATS专用器械和常规开胸器械联合使用。20例肺叶切除共用缝合切割器(ENDOPATH)钉仑44只,肺癌病人通过小切口均作了肺门及纵隔淋巴结摘除。3例术中因胸膜腔粘连肺裂不完整和门血管粘连出血处理困难,将辅助小 相似文献
65.
目的 :探讨卵巢交界性上皮性肿瘤的 DNA含量、倍体分析、S期比例等特点 ,及与组织学分级、预后的关系。方法 :通过计算机图像分析仪 (ICM)测定了 2 2例卵巢交界性肿瘤的 DNA含量 ,并以 38例卵巢良恶性囊性上皮性肿瘤为对照 ,进行倍体分析、S期比例、DI测定。结果 :卵巢交界性肿瘤 DI值 1.11± 0 .0 7,S期比例 33.2 1± 13.72 % ,与良恶性组差异均有显著性意义 (P<0 .0 1)。 2 2例交界性肿瘤中 4例为异倍体肿瘤 ,与恶性组差异有显著性意义 (P<0 .0 1)。 3例复发病例与同组比较其 DI值差异有显著意义 (P<0 .0 1) ,异倍体肿瘤多见。结论 :ICM具有方便、可靠的特点 ,通过测定 DI值、S期比例倍体分析可提示卵巢肿瘤的增殖及预后情况 ,评估潜在恶性的卵巢上皮性肿瘤 ,为临床防治提供更多的信息 相似文献
66.
67.
Xin Sun Yunfeng Guo Shengdu Yang Kai Wang Lan Xie Bai Xue 《Macromolecular chemistry and physics.》2023,224(15):2300072
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields. 相似文献
68.
The predictive value of basal follicle stimulating and growth hormone levels as determined by immunofluorometry during assisted reproduction 总被引:2,自引:0,他引:2
Carin Huyser Francois Le R. Fourie Johan Pentz Philip Hurter 《Journal of assisted reproduction and genetics》1995,12(4):244-251
Purpose
Our purpose was (a) to investigate relationships of baseline endocrine serum levels with selected assisted reproduction (AR) parameters and (b) to evaluate the clinical applicability of an immunofluorometric assay (IFMA) as an alternative to a radioimmunoassay (RIA).Methods Basal endocrine values (analyzed by RIA—rFSH, rLH, and rE2; analyzed by IFMA—fFSH, fLH, and fGH) were determined for female patients (n = 142) preceding ovarian stimulation for AR.Results Specific AR parameters correlated significantly with RIA- and IFMA-determined FSH levels, although IFMA correlations consistently exceeds that of RIA. Cutoff values of fFSH 11.68 IU/L or rFSH 15.0 IU/L indicated a poor response. The high-basal fFSH group was older (34 vs 31 years; P = 0.0334) and yielded fewer oocytes (2.9 vs 4.6 oocytes; P = 0.0018) than the low-basal fFSH group (<11.68 IU/L). Lower cumulative embryo scores and conception rates were also associated with the high-fFSH group, compared to the low-fFSH group.Conclusions This study confirms the negative impact of elevated basal FSH levels on AR. Basal LH, GH, and E2 levels are, in comparison to baseline FSH levels, unsuitable indices for estimating ovarian responsiveness. IFMA can be regarded as an alternative to RIA in both clinical and research laboratories. 相似文献
69.
Anxiety and perceptive functioning of infertile women during in-vitro fertilization: exploratory survey of an Italian sample 总被引:4,自引:0,他引:4
The aim of this study was to study the emotional impact of in-vitro fertilization (IVF) and any possible influence due to the type of diagnosis, duration of infertility, number of cycles and type of responses to treatment. The study was carried out on 200 patients admitted to hospital for the final stages of IVF (oocyte retrieval and embryo transfer). The psychological measures taken into consideration were: state and trait anxiety levels (Stait-Trait Anxiety), unconscious and symptomatic anxiety, perception of self and of others (EWI). Monitoring of anxiety levels during hospitalization highlighted significant differences with respect to the state anxiety values (P < 0.01) and general anxiety (P < 0.05), but not with respect to trait anxiety. The level of state anxiety of women with a diagnosis of infertility was significantly lower (P < 0. 05). Women who have experienced infertility of medium to long duration presented a significantly lower state anxiety value (P < 0. 01). The failure of oocyte fertilization determines a significant increase in state anxiety level (P < 0.01) There were no significant differences in anxiety values with respect to the cycle number. Perceptive functioning was normal. 相似文献
70.
Genia Rozen Stephanie Sii Franca Agresta Debra Gook Alex Polyakov Catharyn Stern 《Reproductive Medicine and Biology》2021,20(3):277-288