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排序方式: 共有1094条查询结果,搜索用时 15 毫秒
971.
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974.
目的观察32P-磷酸铬胶体注入兔类风湿关节炎模型膝关节腔后对外周血淋巴细胞染色体畸变率的影响。方法9只新西兰兔随机分成3组,A组3只为正常对照;B组3只为模型对照;C组3只诱导成模型1周后,右膝关节腔内各注射32P-胶体磷酸铬44.4MBq。3组均在C组核素注射后2个月时经耳缘静脉采血,其中C组另在核素注射前、注射后3d时采血。经培养后比较各组分裂中期淋巴细胞染色体畸变率的变化。结果A、B、C3组外周血淋巴细胞染色体观察均未见双着丝粒,无着丝粒断片率3组无明显差异(P>0.05)。C组各时间点外周血淋巴细胞染色体观察也未发现双着丝粒,无着丝粒断片率也无明显差异(P>0.05)。结论关节腔注射实验剂量的32P-磷酸铬胶体,兔外周血淋巴细胞畸变率的波动在正常范围内,说明放射性滑膜切除术是一种安全的治疗方法。 相似文献
975.
The occurrence of a symptomatic Rathke's cleft cyst without extension into the sella turcica is rare. The purpose of this report is to present such a case, with its clinical manifestation, diagnostic imaging characteristics, operative approach, pathology and review of the literature. 相似文献
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977.
F Bonvicini E Manaresi G Gallinella GA Gentilomi M Musiani M Zerbini 《BJOG : an international journal of obstetrics and gynaecology》2009,116(6):813-817
Objective The purpose of our work was to examine the most reliable laboratory diagnosis of fetal parvovirus B19 infection in hydropic fetuses by evaluating the most appropriate clinical sample and laboratory test.
Design B19 DNA detection in fetal samples and serological signs of B19 infection in the respective mothers. Samples collected between January 2000 and July 2008.
Setting Microbiology, University of Bologna, Bologna, Italy.
Samples One hundred thirty-five fetal samples (58 fetal cord blood and 77 amniotic fluid samples) and 109 serum samples collected from 109 pregnant women.
Methods Validated and certified in situ hybridisation assay (ISH) and polymerase chain reaction–enzyme-linked immunosorbent assay (PCR-ELISA) were performed on fetal samples to detect B19 DNA. B19-specific antibodies were investigated in maternal serum samples by a commercial enzyme immunoassay.
Main outcome measures Parvovirus B19 DNA detection in fetal specimens was analysed in relation to maternal serological signs of infection.
Results Parvovirus B19 DNA was detected in 22.41% of fetal cord blood and 36.36% of amniotic fluid samples. A statistically significant difference was found between DNA detection by ISH (23.70%) and PCR-ELISA (14.81%) ( P = 0.004). Only 11.76% of fetuses with virological diagnosis of B19 infection were from women with serological signs of acute/recent B19 infection.
Conclusions Diagnosis of fetal parvovirus B19 infection cannot always rely on maternal serological investigations but rather on the virological analysis of fetal samples. Both fetal cord blood and amniotic fluid samples are suitable for diagnosis, but the detection of B19 DNA in the cells of amniotic fluid samples by ISH proved to be the most reliable diagnostic system. 相似文献
Design B19 DNA detection in fetal samples and serological signs of B19 infection in the respective mothers. Samples collected between January 2000 and July 2008.
Setting Microbiology, University of Bologna, Bologna, Italy.
Samples One hundred thirty-five fetal samples (58 fetal cord blood and 77 amniotic fluid samples) and 109 serum samples collected from 109 pregnant women.
Methods Validated and certified in situ hybridisation assay (ISH) and polymerase chain reaction–enzyme-linked immunosorbent assay (PCR-ELISA) were performed on fetal samples to detect B19 DNA. B19-specific antibodies were investigated in maternal serum samples by a commercial enzyme immunoassay.
Main outcome measures Parvovirus B19 DNA detection in fetal specimens was analysed in relation to maternal serological signs of infection.
Results Parvovirus B19 DNA was detected in 22.41% of fetal cord blood and 36.36% of amniotic fluid samples. A statistically significant difference was found between DNA detection by ISH (23.70%) and PCR-ELISA (14.81%) ( P = 0.004). Only 11.76% of fetuses with virological diagnosis of B19 infection were from women with serological signs of acute/recent B19 infection.
Conclusions Diagnosis of fetal parvovirus B19 infection cannot always rely on maternal serological investigations but rather on the virological analysis of fetal samples. Both fetal cord blood and amniotic fluid samples are suitable for diagnosis, but the detection of B19 DNA in the cells of amniotic fluid samples by ISH proved to be the most reliable diagnostic system. 相似文献
978.
979.
目的 探讨应用siRNA技术沉默EPAS1 (HIF-2α)基因表达对低氧条件下培养的大鼠肺动脉平滑肌细胞(PASMCs)增殖的影响.方法 原代培养大鼠PASMCs共采用免疫荧光法进行鉴定.构建特异性EPAS1 siRNA脂质体,转染PASMCs,从3个干扰靶点中选取效果最好的靶点进行干扰;在常氧(37℃、5%CO2、20%O2)和低氧(37℃、5%CO2、2%O2)条件下分别培养24、48、72h,采用Western blotting检测PASMCs中EPAS1、VEGF蛋白的表达水平,CCK-8法检测细胞增殖情况.结果 成功分离培养原代大鼠PASMCs并经免疫荧光鉴定证实.将特异性的EPAS1 siRNA脂质体转染到PASMCs,选择干扰效果最好的靶点2进行干扰.与常氧条件比较,低氧条件下PASMCs中VEGF蛋白的表达及细胞增殖水平均明显升高;沉默EPAS1后,无论低氧还是常氧条件下,PASMCs中VEGF蛋白的表达及细胞增殖水平均明显降低.结论 EPAS1基因参与了低氧条件下大鼠PASMCs增殖的调控,其调节可能是通过VEGF介导完成的. 相似文献
980.