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101.
体外培养的人卵母细胞的超微结构 总被引:3,自引:1,他引:3
目的探讨体外培养的人卵母细胞的超微结构。方法用光镜观察体外培养前生发泡期(GV期)、培养后生发泡破裂但仍处于MⅠ期的未成熟卵母细胞和达到MⅡ期的成熟卵母细胞的形态,并将成熟卵母细胞分为优质与非优质;用透射电镜观察卵母细胞的超微结构。结果GV期卵母细胞微绒毛短小稀少;核偏一侧,核仁致密。培养后卵母细胞微绒毛粗大增多,细胞器丰富,高尔基体周围有许多分泌小泡;线粒体和脂滴伴行;卵丘细胞的胞质突起与卵母细胞的微绒毛问形成缝隙连接,卵丘细胞之间形成较多桥粒。成熟的卵母细胞粗面内质网、高尔基体减少,滑面内质网发达,线粒体幼稚化,脂滴融合,皮质颗粒沿质膜下呈线性排列,细胞连接减少,第一极体含多种细胞器。非优质卵母细胞线粒体大量存在膜和嵴模糊、膨大的现象,有的极体碎裂,透明带形态不正常,其周围卵丘细胞的凋亡率较高。结论揭示了体外培养的不同时期、不同质量的人卵母细胞的超微结构。 相似文献
102.
103.
目的 通过观察突变蛋白与野生蛋白过量对卵母细胞成熟过程的影响,分析Uchl1在小鼠卵母细胞离体成熟中发挥的作用及其作用方式。方法 通过原核重组蛋白技术制备点突变(C90S和I93M)和野生型Uchl1蛋白,通过蛋白微量注射技术将突变蛋白与对照蛋白注射到未成熟卵母细胞,或体外培养液中添加突变蛋白与野生型蛋白,分析野生型Uchl1过量,或突变Uchl1-I93M蛋白添加,或泛素水解酶活性缺失的Uchl1-C90S突变蛋白添加,对于卵母细胞体外成熟的影响。结果 显微注射UCHL1融合蛋白的各组之间以及与注射PBS之间, GVBD率差异没有达到统计学显著性;同时培养液中添加Uchl1的GST融合蛋白,相对于无注射对照组,也没有统计学显著差异(P>0.05)。注射GST-C90S融合蛋白组少量GV期卵母细胞体外发育为MII期卵母细胞后呈现极体偏大于对照组。I93M点突变小鼠与WT小鼠比较,GV期卵母细胞体外GVBD率无显著差异。结论 在小鼠卵母细胞中,添加外源性Uchl1,或者有毒性作用的I93M突变体,或者水解酶活性结构改变的C90S突变体,均不影响卵母细胞成熟的GVBD进程。即使构建的I93M点突变小鼠卵母细胞GVBD率无异常。但是,其水解酶活性位点突变影响极体的形成。 相似文献
104.
105.
Jack Yu Jen Huang Ri-Cheng Chian Lucy Gilbert David Fleiszer Hananel Holzer Ezgi Dermitas Shai Elazar Elizur Yariv Gidoni Dan Levin Weon-Young Son Seang Lin Tan 《American journal of surgery》2010,200(1):177-183
Background
We report a novel fertility preservation strategy that may be useful for young breast cancer patients who present with time constraints or concerns about the effect of ovarian stimulation.Methods
The protocol involves retrieval of immature oocyte from unstimulated ovaries followed by in vitro maturation (IVM), and vitrification of oocytes or embryos.Results
Thirty-eight patients (age 24-45 years) underwent vitrification of oocytes (n = 18) or embryos (n = 20). The mean ages were 33.1 ± 5.0 years and 34.7 ± 4.8 years, respectively. The mean days required to complete the egg collection was 13 days. The median numbers of vitrified oocytes and embryos per retrieval were 7 (range 1-22) and 4 (range 1-13), respectively.Conclusions
The strategy of immature oocyte retrieval without ovarian stimulation followed by IVM and oocyte or embryo vitrification, which does not increase the serum estradiol level and delay cancer treatment, represents an attractive option of fertility preservation for many breast cancer patients. 相似文献106.
107.
目的 探讨骨形态发生蛋白(BMP)4/Smad 信号通路在小鼠原始卵泡卵母细胞凋亡中的调控作用。方法 取出生3d的雌性昆明小鼠卵巢,采用两步酶消化法,分离纯化卵母细胞,进行原代培养。将卵母细胞分为3组:正常对照组(Con组)、添加重组人BMP4组(BMP4组)、添加BMP4和BMP4抑制剂6-{4-[2-(1-呱啶基)乙氧基]苯基}-3-(4-吡啶基)吡唑并(1,5-A)嘧啶(dorsomorphin)组(BMP4+抑制剂组)。采用TUNEL法, 检测BMP4对卵母细胞凋亡的影响;采用免疫组织化学染色与实时定量PCR,检测BMP4对卵母细胞中p-Smad1/5/8、sohlh2、c-kit及foxo3a表达的影响。采用RNA干扰技术、转染sohlh2质粒和LY294002处理,探讨BMP4/Smad 信号通路在小鼠原始卵泡卵母细胞凋亡中的调控机制。结果 TUNEL 结果显示,BMP4组凋亡卵母细胞比例明显低于Con组(P<0.05)和BMP4+抑制剂组(P<0.05);加入BMP4可明显促进细胞Smad入核,上调 sohlh2和c-kit表达,抑制foxo3a入核; 转染sohlh2 siRNA 后,可明显阻断BMP4抑制卵母细胞凋亡的作用;转染sohlh2质粒后,p-foxo3a表达量显著增加,LY294002可明显抑制sohlh2促进foxo3a磷酸化的作用。 结论 激活BMP4/Smad信号通路可抑制小鼠原始卵泡卵母细胞的凋亡,其作用机制可能是通过上调sohlh2和c-kit基因表达,进而调控foxo3a入核而实现的。 相似文献
108.
《Journal of pediatric and adolescent gynecology》2014,27(6):342-346
ObjectiveTo preliminarily study the feasibility of oocyte cryopreservation in postpubertal girls aged between 13 and 15 years who were at risk for premature ovarian failure due to the accelerated follicle loss associated with Turner syndrome or cancer treatments.DesignRetrospective cohort and review of literature.SettingAcademic fertility preservation unit.ParticipantsThree girls diagnosed with Turner syndrome, 1 girl diagnosed with germ-cell tumor. and 1 girl diagnosed with lymphoblastic leukemia.InterventionsAssessment of ovarian reserve, ovarian stimulation, oocyte retrieval, in vitro maturation, and mature oocyte cryopreservation.Main Outcome MeasureResponse to ovarian stimulation, number of mature oocytes cryopreserved and complications, if any.ResultsMean anti-müllerian hormone, baseline follical stimulating hormone, estradiol, and antral follicle counts were 1.30 ± 0.39, 6.08 ± 2.63, 41.39 ± 24.68, 8.0 ± 3.2; respectively. In Turner girls the ovarian reserve assessment indicated already diminished ovarian reserve. Ovarian stimulation and oocyte cryopreservation was successfully performed in all female children referred for fertility preservation. A range of 4-11 mature oocytes (mean 8.1 ± 3.4) was cryopreserved without any complications. All girls tolerated the procedure well.ConclusionsOocyte cryopreservation is a feasible technique in selected female children at risk for premature ovarian failure. Further studies would be beneficial to test the success of oocyte cryopreservation in young girls. 相似文献
109.
J. Sudiman L. J. Ritter D. K. Feil X. Wang K. Chan D. G. Mottershead D. M. Robertson J. G. Thompson R. B. Gilchrist 《Journal of assisted reproduction and genetics》2014,31(3):295-306
Purpose
We hypothesised that varying native oocyte-secreted factor (OSF) exposure or using different recombinant OSF peptides would have differential effects on post-in vitro maturation (IVM) embryo and fetal development.Methods
Mouse cumulus oocyte complexes (COCs) were treated with the purified mature domain of GDF9 and/or BMP15 or were co-cultured with denuded oocytes (DOs) from 0 h or 3 h of IVM. DOs were matured for 3 h as either intact COCs+/-FSH before denuding, or as DOs + FSH. COCs were fertilised and blastocyst development was assessed on days 5 and 6, and either differentially stained for ICM numbers or vitrified/warmed embryos were transferred to recipients to assess implantation and fetal rates.Results
No improvement in embryo development was observed with the addition of GDF9 and/or BMP15 to IVM. In contrast, embryos derived from COCs co-cultured with DOs had significantly improved blastocyst rates and ICM numbers compared to controls (P < 0.05). The highest response was obtained when DOs were first added to COCs at 3 h of IVM, after being pre-treated (0–3 h) as COCs + FSH. Compared to control, co-culture with DOs from 3 h did not affect implantation rates but more than doubled fetal yield (21 % vs 48 %; P < 0.05). GDF9 Western blot analysis was unable to detect any differences in quantity or form of GDF9 (17 and 65 kDa) in extracts of DO at 0 h or 3 h.Conclusions
This study provides new knowledge on means to improve oocyte quality in vitro which has the potential to significantly aid human infertility treatment and animal embryo production technologies. 相似文献110.
Yoko Yoshida Yoshiki Yamashita Natsuho Saito Yoshihiro Ono Hikaru Yamamoto Yoko Nakamura Atsushi Hayashi Yoshito Terai Masahide Ohmichi 《Journal of assisted reproduction and genetics》2014,31(2):163-168