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901.
Feto-maternal immune interaction at the placental level 总被引:7,自引:0,他引:7
A special interaction is established during pregnancy between the maternal immune system and fetal cells to allow the survival and the normal growth of the fetus. Fetal cells expressing paternal alloantigens are not recognized as foreign by the mother because of an efficient anatomic barrier and a local immunosuppression determined by the interplay of locally produced cytokines, biologically active molecules and hormones. A special balance between TH1 and TH2 lymphocytes has also been observed at the feto-maternal barrier that contribute to control the immune response at this level. An important role is played by trophoblast cells that act as a physical barrier forming a continuous layer and exert immunomodulatory function. Trophoblast cells have also been shown to express regulators of the complement system and to downregulate the expression of HLA antigens. Dysfunction of these cells leads to morphological and functional alterations of the feto-maternal barrier as well as to hormonal and immune imbalance and may contribute to the development of pathologic conditions of pregnancy, such as recurrent spontaneous abortions. Efforts are still needed to better understand the physiology of the feto-maternal interaction and the pathogenetic mechanisms responsible for tissue damage in pathologic conditions of pregnancy. 相似文献
902.
903.
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
904.
905.
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
906.
907.
908.
909.
目的:探讨丹参酮对高血压肾病的治疗作用。方法:选择符合高血压肾病入选标准的慢性肾病(CKD)Ⅰ~Ⅲ期患者60例,基础治疗全部用氯沙坦,随机分为丹参酮组、基础治疗对照组,治疗用药2周,检测并比较各组血压、肾功能、24 h尿蛋白定量、尿N-乙酰-β-D氨基葡萄糖苷酶(NAG)等的变化。结果:2组治疗前、后血压变化无明显差异;丹参酮组治疗2周时血肌酐(SCr)水平较基线下降[(162.2±10.1)μmol/L比(134.0±7.1)μmol/L],与对照组治疗2周时[(151.8±8.3)μmol/L]比较差异有统计学意义(P<0.05),但治疗后组间比较无明显差异。与基线相比,丹参酮组尿NAG下降有明显差异,氯沙坦组无明显下降趋势。结论:在氯沙坦降低蛋白尿的基础上,丹参酮还具有保护肾小管功能及延缓肾功能进展的作用,且安全性好,是高血压肾病治疗的可选药物之一。 相似文献
910.
Benedetto Manuti Paolo Rizza Aida Bianco Carmelo GA Nobile Maria Pavia 《BMC public health》2010,10(1):350