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We describe three cases of fetal intracranial teratoma diagnosed by ultrasound and review the literature. Sonographic features include cranial enlargement, gross distortion of normal cerebral architecture by a hyperechoic, multicystic mass, and polyhydramnios. Despite early diagnosis, the cesarean section rate is high and the overall prognosis is dismal.  相似文献   
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中药升麻的化学成分   总被引:14,自引:0,他引:14  
李从军  陈迪华  肖培根 《药学学报》1993,28(10):777-781
从中药兴安升麻[Cimicifuga dahurica(Turcz.)Maxim.]的干燥根茎中分得五个化合物,其中四个为三萜木糖甙:升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅰ),25-O-乙酰升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅱ),12-羟基升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅲ),升麻醇-3-O-β-D-吡喃木糖基(3→1)-β-D-吡喃木糖甙(23R,24S)(Ⅳ),另一个为异阿魏酸(Ⅴ)。Ⅲ和Ⅳ为新化合物,通过光谱(IR,MS,1H及13C NMR)解析确定了它们的结构,分别命名为升麻甙A(cimiside A)和升麻甙B(cimiside B)。  相似文献   
106.
In this study, we compared pregnancy and delivery outcomes after the utilization of assisted reproductive technologies (ART) in Europe and the United States (US). ART outcomes were compared between Europe and the US for the year 2001, based on formal reports published by the European Society for Human Reproduction and Embryology (ESHRE) and the Center for Disease Control and Prevention (CDC) in collaboration with the American Society for Reproductive Medicine (ASRM) and Society for ART (SART). Europe utilizes ART at approximately twice the rate of the US (P < 0.001). United States patients showed a significantly decreased likelihood of reaching oocyte retrieval (P < 0.001) and embryo transfer (P < 0.001). Despite this lower chance of reaching oocyte retrievals and embryo transfers, US patients experienced significantly higher clinical pregnancy rates (P < 0.001) and delivery rates per started cycle (P < 0.001) than European patients. Amongst patients reaching oocyte retrieval, the difference in clinical pregnancy rates and live birth rates was even more pronounced in favour of the US. However, US patients received significantly more embryos per embryo transfer (P < 0.001) and experienced a significantly higher multiple pregnancy rate (P < 0.001). Significant differences in favour of US patients in pregnancy rates and live birth rates were also observed for frozen embryo cycles and oocyte donation cycles, where the difference was most pronounced. The better pregnancy and live birth outcomes in the US are not explainable by the transfer of larger embryo numbers alone.  相似文献   
107.
BACKGROUND: The aim of this study was to investigate the effect of treatment with dehydroepiandrosterone (DHEA) on fertility outcomes among women with diminished ovarian reserve. MATERIALS AND METHODS: This is a case-control study in an academically affiliated private infertility centre. Twenty-five women with significantly diminished ovarian reserve had one IVF cycle before and after DHEA treatment, with otherwise identical hormonal stimulation. Women received 75 mg of DHEA daily (25 mg three times daily) for an average of 17.6 +/- 2.13 weeks. We performed a comparison of IVF outcome parameters, before and after DHEA treatment, including peak estradiol (E(2)) levels, oocyte and embryo numbers, oocyte and embryo quality and embryo transfer statistics. RESULTS: Paired analysis of IVF cycle outcomes in 25 patients, who underwent cycles both before and after DHEA supplementation, demonstrated significant increases in fertilized oocytes (P < 0.001), normal day 3 embryos (P = 0.001), embryos transferred (P = 0.005) and average embryo scores per oocyte (P < 0.001) after DHEA treatment. CONCLUSION: This study confirms the previously reported beneficial effects of DHEA supplementation on ovarian function in women with diminished ovarian reserve.  相似文献   
108.
BACKGROUND: Photochemical methods can effectively inactivate extracellular viruses and bacteria found in blood components. Treatment of plasma with methylene blue (MB), a phenothiazine dye, and visible light inactivates enveloped viruses including HIV-1. The effects of MB- treated plasma on cellular components stored in vitro have not been well characterized. STUDY DESIGN AND METHODS: MB-treated plasma (83 microg MB/250 mL plasma) was added to single-donor platelets, stored AS- 1 red cells (RBCs), irradiated RBCs, and frozen-deglycerolized RBCs. In vitro platelet assays performed after 1 and 5 days of storage in MB- treated plasma included pH, pO2, pCO2, HCO3, platelet number, lactate dehydrogenase, glucose, osmotic recovery, and CD62 expression. RBC components were examined at specific intervals for leakage of potassium, plasma hemoglobin level, and percentage of hemolysis. Direct antiglobulin tests, osmotic fragilities, and RBC antigen stability tests were also performed on RBCs stored in MB-treated plasma. Components stored with autologous plasma or nontreated allogeneic plasma served as controls. RESULTS: Similar storage-induced changes in pH, glucose, and platelet numbers, as well as increases in lactate dehydrogenase, CD62 expression, and lactate were seen in single-donor platelets stored with MB-treated and control plasma. Platelet morphology scores and osmotic recoveries were not altered. Plasma hemoglobin and potassium and percentage of hemolysis increased equally in the various RBC components stored with MB-treated or nontreated plasma. Osmotic fragility and RBC antigen stability were not appreciably altered by MB-treated plasma. CONCLUSION: Plasma treated by MB photoinactivation can be used for in vitro resuspension and storage of platelets or RBCs, because of the lack of influence of MB-treated plasma on a variety of in vitro platelet and RBC assays.  相似文献   
109.
Most axons in the CNS innervate specific subregions or layers of their target regions and form contacts with specific types of target neurons, but the molecular basis of this process is not well understood. To determine whether collapsin-1/semaphorin-III/D, a molecule known to repel specific axons, might guide afferent axons within their cerebellar targets, we characterized its expression by in situ hybridization and observed its effects on mossy and climbing fiber extension and growth cone size in vitro. In newborn mice sema-D is expressed by cerebellar Purkinje cells in parasagittal bands located medially and in some cells of the cerebellar nuclei. Later, sema-D expression in Purkinje cells broadens such that banded expression is no longer prominent, and expression is detected in progressively more lateral regions. By postnatal day 16, expression is observed throughout the cerebellar mediolateral axis. Collapsin-1 protein, the chick ortholog of sema-D, did not inhibit the extension of neurites from explants of inferior olivary nuclei, the source of climbing fibers that innervate Purkinje cells. In contrast, when it was applied to axons extending from basilar pontine explants, a source of mossy fiber afferents of granule cells, collapsin-1 caused most pontine growth cones to collapse, as evidenced by a reduction in growth cone size of up to 59%. Moreover, 63% of pontine growth cones arrested their extension or retracted. Its effects on mossy fiber extension and its distribution suggest that sema-D prevents mossy fibers from innervating inappropriate cerebellar target regions and cell types.  相似文献   
110.
HPLC法测定地西泮和艾司唑仑的血药浓度   总被引:9,自引:0,他引:9  
建立HPLC法同时测定地西泮和艾司唑仑血药浓度。方法:以Ultrasphere-ODS5μm4.6mm*25cm色谱柱为分离柱,流动相:甲醇-乙腈-水(40:20:40);检测波长为254nm,以外标法峰面积定量。结论本法可用于血药浓度测定。  相似文献   
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