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1.
Objective To determine the concentrations of cholesterol sulfate ( CS) in human sera and pla-cental villi during the course of pregnancy. And to analyze its inhibitory activity on thrombin and further characterize the functional significance of CS. Methods The concentrations of CS were determined by thin-layer chromatog-raphy (TLC) on 60 cases of normal pregnant women and 30 cases of normal placental villi. The effect of CS in human sera on the activity of thrombin was analyzed. Results The concentrations of CS in human sera gradually increased from the first to third trimester of gestation with a correlation coefficient of 0. 69, and a correlation between the concentration of CS and weeks of gestation (P <0. 01). CS was also contained in the placental villi, and its concentrations at the second and third trimester of gestations were 4. 7 and 6. 2-fold of that at the first trimester of gestation. CS inhibited the activity of thrombin. Conclusion Placental CS is one of the sources of CS in the serum , pr 相似文献
2.
目的:观察妊高征患者胎盘床浸润的滋养细胞内皮素(ET-1)的表达情况,探讨妊高征的发病机理。方法:收集正常妊娠病例30例,妊高征共70例,其中轻度30例,中度20例,重度20例,用免疫组化方法对妊高征和正常妊娠的胎盘床蜕膜段和肌层浸润的滋养细胞进行ET-1的标记。结果:ET-1在妊高征胎盘床蜕膜段浸润的滋养细胞的表达与正常妊娠无明显差别(P>0.05),ET-1在妊高征胎盘床肌层浸润的滋养细胞的表达明显高于正常妊娠(P<0.05)。讨论:妊高征时胎盘床肌层浸润的滋养细胞分泌的内皮素明显增多,提示妊高征的发生可能与肌层浸润的滋养细胞分泌的内皮素增多有关。 相似文献
3.
目的探讨胎盘早期剥离(胎盘早剥)的产前诊断和处理。方法对我院近10年发生的13例胎盘早剥作回顾性分析。结果妊高征及慢性高血压病占本组病因的46.2%。本组围产儿死亡率为23.08%,孕产妇死亡率为0。子宫卒中发生率46.15%,产后出血30.77%,DIC 7.70%。阴道出血、腹痛、胎心异常或消失、血性羊水为主要临床表现。产前诊断率为46.15%,B超检出率为60%。结论胎盘早剥的诊断需结合患者临床表现、发病诱因、B超检查结果全面考虑,确诊后应尽快终止妊娠。 相似文献
4.
Focal reduction of villous blood flow in early indomethacin
enteropathy: a dynamic vascular study in the rat 总被引:3,自引:0,他引:3
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Background—Oral indomethacin causes villousshortening, microvascular damage, and distortion, which might inducemucosal ischaemia and necrosis.
Aims—In order to determine the early events inindomethacin induced jejunal injury we examined the temporal relationsbetween morphological damage and changes in villous blood flowfollowing indomethacin.
Methods—In anaesthetised rats, mid jejunal villiwere exteriorised in a chamber and observed by fluorescence microscopy.Blood flow in surface capillaries was calculated from velocities and diameters. Indomethacin was applied by both luminal and intravenous routes for 90 minutes, after which the animal was perfusion fixed andthe villi were processed for histological examination. Control animalsreceived intravenous or luminal bicarbonate (1.25%).
Results—Blood flow slowed in individual villi at20 minutes, and progressed to complete stasis (in another group) by 45 minutes. Histological examination at 20 minutes revealed microvascular distortion, but no villous shortening: crypt depth:villous height ratios were 0.356 (0.02) in test and 0.386 (0.01) in surrounding villi(p>0.5). At stasis, the villi under study showed epithelial clumpingand were shortened: crypt depth:villous height ratios were 0.92 (0.2)in test and 0.42 (0.06) in surrounding villi (p<0.02). Vehicle alonehad no effect on either blood flow or histology.
Conclusions—Focal slowing of villous blood flowand microvascular distortion precede villus shortening and epithelialdisruption, and indicate that damage to surface microvasculature is anearly event in indomethacin induced mucosal injury in this model.
Aims—In order to determine the early events inindomethacin induced jejunal injury we examined the temporal relationsbetween morphological damage and changes in villous blood flowfollowing indomethacin.
Methods—In anaesthetised rats, mid jejunal villiwere exteriorised in a chamber and observed by fluorescence microscopy.Blood flow in surface capillaries was calculated from velocities and diameters. Indomethacin was applied by both luminal and intravenous routes for 90 minutes, after which the animal was perfusion fixed andthe villi were processed for histological examination. Control animalsreceived intravenous or luminal bicarbonate (1.25%).
Results—Blood flow slowed in individual villi at20 minutes, and progressed to complete stasis (in another group) by 45 minutes. Histological examination at 20 minutes revealed microvascular distortion, but no villous shortening: crypt depth:villous height ratios were 0.356 (0.02) in test and 0.386 (0.01) in surrounding villi(p>0.5). At stasis, the villi under study showed epithelial clumpingand were shortened: crypt depth:villous height ratios were 0.92 (0.2)in test and 0.42 (0.06) in surrounding villi (p<0.02). Vehicle alonehad no effect on either blood flow or histology.
Conclusions—Focal slowing of villous blood flowand microvascular distortion precede villus shortening and epithelialdisruption, and indicate that damage to surface microvasculature is anearly event in indomethacin induced mucosal injury in this model.
Keywords:indomethacin; jejunum; villi; microcirculation; endothelium; microthrombi
相似文献5.
Natural interferon enhances expression of placental alkaline phosphatase in human seminoma xenograft
T. Imao K. Koshida H. Konaka T. Uchibayashi K. Yokoyama K. Hirano M. Namiki 《Urological research》1998,26(6):377-382
The purpose of this study was to investigate the effect of natural interferon (IFN) on the expression of placental alkaline
phosphatase (PLAP) in a human seminoma xenograft in severe combined immunodeficient mice. Mice were injected intramuscularly
with 3 × 105 U/mouse of IFN, twice a day, for five consecutive days. A significant increase in PLAP level of the xenografts followed IFN
treatment. A radiolabeled anti-PLAP monoclonal antibody (MAb) was intravenously injected on the first day of IFN administration
in order to determine if IFN has the potential to enhance the efficacy of an anti-PLAP MAb in the detection of seminoma. Enhanced
retention of the anti-PLAP MAb was observed at 7 and 11 days after MAb administration. Thus, IFN treatment appears to have
some effect on the efficacy of the anti-PLAP MAb in the detection of seminoma xenografts.
Received: 26 September 1997 / Accepted: 23 April 1998 相似文献
6.
TheInfluencesofMifepristone,NorethisteroneandTamoxifenontheGlycosphingolipidsCompositionsfromHumanChorionicTissueduringEarlyP... 相似文献
7.
J. A. J. M. van den Hurk P. M. van Zandvoort F. Brunsmann I. H. Pawlowitzki W. Holzgreve P. Szabo F. P. M. Cremers B. A. van Oost 《American journal of medical genetics. Part A》1992,44(6):822-823
We performed prenatal testing to predict the inheritance of choroideremia (CHM) using a linked polymorphic DNA marker, DXS95. DNA analysis of chorionic villi at the 12th week of pregnancy indicated that the allele at risk had not been passed from the heterozygous mother to the fetus. This prenatal exclusion of choroideremia was confirmed by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis. © 1992 Wiley-Liss, Inc. 相似文献
8.
The umbilical vascular bed of the rat placenta was perfused in situ. Ouabain (10–4M) in the perfusion fluid had no effect on the unidirectional flux of Na+ from the maternal (electrically negative) to the foetal (electrically positive) side of the placenta, or on the transplacental potential difference. This was taken to indicate that there is no significant active transport of Na+ across the placenta of the rat. 相似文献
9.
10.
人早孕母胎界面SOCS1、SOCS2、SOCS3表达 总被引:2,自引:0,他引:2
目的:研究正常早孕绒毛及蜕膜组织细胞因子信号转导负调控因子(Suppressors of cytoldne signaling,SOCS)基因和蛋白水平表达,以揭示SOCS在母胎界面生理性调节作用。方法:半定量RT-PCR检测早孕绒毛组织、蜕膜组织及原代培养早孕滋养细胞、蜕膜基质细胞SOCS1、SOCS2、SOCS3 mRNA水平;Western blot检测早孕绒毛组织及蜕膜组织SOCS1、SOCS2、SOCS3蛋白表达;免疫组化定位SOCS1、SOCS2、SOCS3在早孕绒毛组织、蜕膜组织表达;ELISA检测滋养细胞、蜕膜基质细胞分泌IL-10、IFN-γ。结果:正常母胎界面见SOCS1、SOCS2、SOCS3基因表达,其中SOCS3绒毛/蜕膜阳性率73.7%/71.1%;SOCS2绒毛/蜕膜阳性率50.0%/39.5%,SOCS1最少,绒毛/蜕膜阳性率34.2%/31.6%;SOCS1、SOCS2、SOCS3蛋白表达与转录水平基本一致;正常母胎界面SOCS1、SOCS2、SOCS3表达主要定位于绒毛滋养细胞和蜕膜间质;体外无血清培养滋养细胞和蜕膜基质细胞SOCS2、SOCS3低表达,SOCS1未见表达,其分泌的IL-10随时间而增高(P〈0.05)。结论:正常早孕母胎界面表达SOCS1、SOCS2、SOCS3,无刺激条件下滋养细胞和蜕膜基质细胞低表达SOCS2、SOCS3,SOCS在正常妊娠Th平衡中具有重要意义。 相似文献