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排序方式: 共有2441条查询结果,搜索用时 15 毫秒
1.
Takayuki Sakurai Satoshi Watanabe Minoru Kimura Masahiro Sato 《Reproductive Medicine and Biology》2006,5(1):43-50
Background and Aims: The aim of this study was to determine which mouse strains exhibit tolerance to cooling when fertilized oocytes have been stored at 4°C.
Methods: In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results: Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion: Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50) 相似文献
Methods: In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results: Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion: Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50) 相似文献
2.
M. Sh. Verbitskii Ya. N. Gotsulyak 《Bulletin of experimental biology and medicine》1997,123(1):100-104
The effects of antiovarian antiserum and monoclonal antibodies to the oolemma antigens on the ultrastructure of mouse oocytes
and their microenvironment are studied. The antioolemma monoclonal antibodies cause more pronounced degenerative changes in
the oocyte that in its microenvironment. Antiovarian antiserum induces greater changes in the microenvironment than in the
oocyte. Changes induced in the oocyte by the antiserum are secondary relative to changes occurring in the microenvironment,
while changes observed in the oocyte treated with monoclonal antibodies are primary.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 1, pp. 115–119, January, 1997 相似文献
3.
家兔未成熟心肌缺血再灌注肌浆网摄钙功能的初步研究 总被引:5,自引:2,他引:3
目的 :从亚细胞水平研究未成熟心肌缺血 -再灌注损伤中肌浆网 (SarcoplasmicReticulum ,SR)摄钙功能。方法 :36只家兔随机分为 4组 ,进行离体心灌注。组Ⅰ :幼兔 ,单纯灌注 30min ;组Ⅱ :幼兔 ,停搏 6 0min ,再灌注 30min。组Ⅲ、组Ⅳ为成兔 ,处理分别同组Ⅰ、组Ⅱ ,进行对照。测定各组心功能、冠状动脉流出液血气 ,单细胞内游离钙离子浓度 ([Ca2 + ]i) ,肌浆网Ca2 + -ATPase活性 ,肌浆网45Ca2 + 摄取。结果 :缺血 -再灌注后 ,成熟与未成熟心肌均发生钙超载 (P >0 .0 5 )。未成熟心肌肌浆网Ca2 + ATPase活性 ,肌浆网45Ca2 + 摄取恢复率 ,明显高于成熟心肌 (P <0 .0 5 )。结论 :未成熟心肌缺血 -再灌注损伤钙超载机制不同于成熟心肌 ,肌浆网钙摄取功能 ,在钙超载损伤中不起主要作用。 相似文献
4.
在微量注射大量肝脏mRNA之后,通过电压箝方法进行功能鉴定,两栖类卵母细胞成功地表达了AVPV1a受体。但在灌流AV4-8溶液时,却不能诱导卵母细胞产生内向振荡电流反应。提示AVP4-8不能通过AVPV1a受体而介导生理学效应。 相似文献
5.
Oocyte donation by gamete intra-Fallopian transfer to amenorrhoeic and cycling patients given replacement steroids 总被引:1,自引:1,他引:0
Formigli L.; Roccio C.; Belotti G.; Stangalini A.; Coglitore M.T.; Formigli G. 《Human reproduction (Oxford, England)》1989,4(7):772-776
Thirteen procedures of oocyte donation by the gamete intra-Fallopiantransfer (GIFT) technique are described. The patients includedsix women with premature ovarian failure, four normally cyclingwomen with unexplained infertility who responded poorly to super-ovulationinduction in preparation for GIFT, and lastly one woman carrierof a 16/21 balanced translocation. Two patients had oocytesdonated on two occasions. Oocyte donors were recruited eitheramong the patients' relatives (n = 4), or among GIFT or IVFpatients (n = 8), who altruistically donated their extra oocytes.Donors were superovulated and oocytes collected laparoscopicallyor vaginally under ultrasound guidance. Donors did not sufferany complications. Recipients were given exogenous oestrogens,and exogenous progesterone was added from the day of donation.Seven clinical pregnancies were obtained (53.8% per attempt);one set of triplets aborted at 14 weeks. Donation took placeon replacement day 1218 and pregnancies were obtainedin patients receiving oocytes throughout this temporal window.The increasing availability of embryo-freezing facilities willprobably reduce the number of ova available for donation. Therefore,the patients' families may become a precious source of donatedeggs, especially for those patients having large families, withstrong family ties. 相似文献
6.
The progesterone production of the granulosa cells of the cumulus oocyte complex correlates very well with the cleavagepotential of embryos in an IVF system. The method is simpleand can be easily performed by any laboratory associated withIVF. Furthermore, high intratubal progesterone levels in theimmediate post-ovulatory period are probably important in prolongingthe intra-ampullary residence of the oocyte or embryo untilthe uterine endometnum is optimal for implantation. 相似文献
7.
A. Wisanto P. Braeckmans M. Camus P. Devroey I. Khan C. Staesssen J. Smitz L. Van Waesberghe A. C. Van Steirteghem 《Journal of assisted reproduction and genetics》1988,5(2):107-111
Either a percutaneous-transvesical, a transvaginal, or a perurethral-transvesical approach can be used for oocyte recovery under ultrasound guidance in an in vitro fertilization and embryo transfer program. After having experienced these three different approaches in our program, we preferentially used the perurethral-transvesical approach as our routine technique for oocyte recovery under ultrasound guidance. We feel that this method is easier to perform and also carrier less risk for contamination. From January to December 1986, 186 oocyte retrievals under ultrasound guidance were performed. In 7 cases no oocytes were found despite normal ovarian stimulation. A total of 767 oocytes was collected; the fertilization rate was 71.8%. Forty pregnancies were achieved (21.5% per attempt or 27.7% per embryo replacement). Except for transient hematuria, no complications were observed. 相似文献
8.
Summary: The goal of this study was to develop a new model of ischemia-induced seizures in immature rats using injection of vasoconstrictor Endothelin-1 (ET-1) into the brain. ET-1 (10, 20, or 40 pmol) was infused into the left dorsal hippocampus of freely moving Wistar rats 12 (P12) and 25 (P25) days old. Animals were then video/EEG-monitored for 100 min and monitoring was repeated 22 h later. Parameters of electrographic seizures (frequency and mean duration) as well as pattern of their behavioral correlates were evaluated. The pattern of behavioral seizures was used to develop model-specific scoring system. Cresyl violet and Fluoro Jade-B-staining were used to evaluate brain damage. Extension of the lesion was correlated with seizure severity. After ET-1-injection, seizures occurred in 83–100% animals of all age-and-dose groups and persisted for 24 h except P12 rats with 10 pmol. There were no differences in average seizure duration (18–40 s) or seizure frequency (3–7 seizures/100 min) among individual dose-groups. Between the 1st and 2nd observation period, total seizure duration decreased in 71% of P12 and 47% of P25 rats. Electrographic seizure activity was most frequently accompanied by clonus, incidence of more severe convulsions (barrel rolling or generalized clonic seizures) increased with dose of ET-1. Morphologic examination did not reveal any dose-related difference in damage severity, hippocampal damage was however more extensive in P12 compared to P25 animals. Seizure severity correlated positively with severity of the damage in both age groups. Our study presents focal injection of ET-1 into the brain as a new and practical model of ischemia-induced seizures in immature rats. 相似文献
9.
Gozde Erkanli Feriha Ercan Serap Sirvanci Emsal Salik Hasan Raci Yananli Filiz Onat Tangul San 《International journal of developmental neuroscience》2007,25(6):399-407
Five-day-old Wistar albino rats were injected with kainic acid (KA) or saline i.p. to investigate time-dependent alterations in morphology and number of basic fibroblast growth factor (bFGF) immunoreactive (-ir) astrocytes and neurons in hippocampus at 15, 30, and 90 days after the injections. Sections were stained with cresyl violet for morphological evaluation and bFGF immunohistochemistry was used for quantitative evaluation of bFGF-ir cell density. Fifteen days after KA injection, there was gliosis but no neuronal loss although disorganization in CA1, CA3, CA4 pyramidal layers and neuronal loss were evident 30 and 90 days after the injection. KA injected rats demonstrated significantly increased number of bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number of bFGF-ir cells after 30 and 90 days. The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells suggesting that protective effects of bFGF may be altered during epileptogenesis in hippocampus. 相似文献
10.
Morris R.S.; Paulson R.J.; Sauer M.V.; Lobo R.A. 《Human reproduction (Oxford, England)》1995,10(4):811-814
Ovarian hyperstimulation syndrome (OHSS) is a serious complicationof gonadotrophin usage but it is difficult to accurately predictits occurrence. Previous investigators have identified the combinationof high oestradiol concentrations and oocyte number as beingpredictive in 80% of cases. In this study we sought to identifythe incidence of severe OHSS in patients with high oestradiolconcentrations and large numbers of oocytes and to evaluatethe importance of pregnancy in the development of OHSS. Between1990 and 1993, we studied 139 cycles using two assisted reproductivetechniques [oocyte donor, n =72; in-vitro fertilization (IVF),n = 67] in which either oestradiol (>4000 pg/ml), oocytenumber (>25), or both were elevated. OHSS was diagnosed bystandard criteria. There were no cases of severe OHSS in theoocyte donor group and six in the IVF group. Among 10 patientswith oestradiol concentration >6000 pg/ml and >30 oocytes,only one had OHSS (10%). The relative risk of OHSS with pregnancywas 12 (confidence interval 2.1866.14). We conclude thatthe risk of OHSS even at high levels of stimulation is lowerthan previously believed. Secondly, donors have a very low riskof OHSS, probably because of the absence of pregnancy. As such,cryopreservation of all oocytes in IVF cycles is a reasonablealternative to cycle cancellation or use of adjunctive medication. 相似文献