全文获取类型
收费全文 | 3724篇 |
免费 | 244篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 38篇 |
儿科学 | 121篇 |
妇产科学 | 67篇 |
基础医学 | 536篇 |
口腔科学 | 39篇 |
临床医学 | 334篇 |
内科学 | 1005篇 |
皮肤病学 | 83篇 |
神经病学 | 244篇 |
特种医学 | 419篇 |
外国民族医学 | 10篇 |
外科学 | 361篇 |
综合类 | 30篇 |
一般理论 | 6篇 |
预防医学 | 201篇 |
眼科学 | 37篇 |
药学 | 232篇 |
中国医学 | 4篇 |
肿瘤学 | 259篇 |
出版年
2023年 | 15篇 |
2022年 | 18篇 |
2021年 | 43篇 |
2020年 | 26篇 |
2019年 | 61篇 |
2018年 | 65篇 |
2017年 | 37篇 |
2016年 | 45篇 |
2015年 | 60篇 |
2014年 | 76篇 |
2013年 | 127篇 |
2012年 | 176篇 |
2011年 | 139篇 |
2010年 | 112篇 |
2009年 | 151篇 |
2008年 | 166篇 |
2007年 | 182篇 |
2006年 | 136篇 |
2005年 | 148篇 |
2004年 | 112篇 |
2003年 | 108篇 |
2002年 | 118篇 |
2001年 | 123篇 |
2000年 | 116篇 |
1999年 | 134篇 |
1998年 | 107篇 |
1997年 | 109篇 |
1996年 | 131篇 |
1995年 | 82篇 |
1994年 | 78篇 |
1993年 | 72篇 |
1992年 | 79篇 |
1991年 | 64篇 |
1990年 | 71篇 |
1989年 | 93篇 |
1988年 | 97篇 |
1987年 | 69篇 |
1986年 | 73篇 |
1985年 | 69篇 |
1984年 | 37篇 |
1983年 | 38篇 |
1982年 | 24篇 |
1981年 | 18篇 |
1980年 | 22篇 |
1979年 | 24篇 |
1978年 | 19篇 |
1977年 | 20篇 |
1976年 | 21篇 |
1975年 | 20篇 |
1974年 | 16篇 |
排序方式: 共有4026条查询结果,搜索用时 250 毫秒
21.
22.
23.
24.
25.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
26.
Polymorphism and drug-selected mutations in the protease gene of human immunodeficiency virus type 2 from patients living in Southern France
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Colson P Henry M Tourres C Lozachmeur D Gallais H Gastaut JA Moreau J Tamalet C 《Journal of clinical microbiology》2004,42(2):570-577
The susceptibility of human immunodeficiency virus type 2 (HIV-2) to protease inhibitors (PI) is largely unknown. We studied HIV-2 protease genes from 21 HIV-2-infected patients who were exposed or not exposed to PI. The aim of this study was (i). to characterize the polymorphism of HIV-2 protease in the absence of drug, (ii). to know whether the HIV-2 protease gene naturally harbors HIV-1 drug resistance codons, and (iii). to identify mutations emerging under PI-selective pressure. Sixty-five HIV-2 RNA or proviral DNA samples were directly sequenced from the plasma or peripheral blood mononuclear cells of 8 patients who had received PI and 13 patients who had never received any antiretroviral. In untreated patients, the highest amino acid variability in HIV-2 protease was observed at positions 14, 40, 43, 46, 65 and 70, and seven codons (10V, 32I, 36I, 46I, 47V, 71V, and 73A) associated with drug resistance in HIV-1 were highly prevalent. In addition, at six positions (positions 7, 46, 62, 71, 90, and 99), the amino acid variability or the amino acid frequencies or both differed significantly in PI-treated and untreated patients, suggesting that mutations 7K-->R, 46V-->I, 62V-->A/T, 71V-->I, 90L-->M and 99L-->F were occurring under PI-selective pressure. At these positions, at least one sample simultaneously harbored both wild-type and mutated codons, while substitutions at positions 62, 71, 90, and 99 were confirmed in a longitudinal analysis. Moreover, the presence of codons 46I and 99F in the absence of drug in HIV-2 subtype B proteases may reflect natural resistance to PI. In conclusion, the present study revealed that HIV-2 strains harbor specific patterns of natural polymorphism and resistance. 相似文献
27.
J. Pillet B. Enon P. Cronier Ph. Mercier P. Moreau J. M. Chevalier 《Surgical and radiologic anatomy : SRA》1982,4(4):307-314
Summary The arteries of the gut, and in particular in the inferior mesenteric artery (a. mesenterica inferior), normally play a minimal role in supplying blood to the lower limbs. However, this is far from being the case in aorto-iliac obstruction. The anatomical anastomoses between the intestinal arterial system and the arteries of the lower limb hypertrophy and in one case out of ten become predominant.In the present study the path taken and the relations of the collaterals of the intestinal arteries and of their anastomoses have been traced, and several collateral pathways are described.
Rôle des artères mésentériques dans la revascularisation artérielle des membres inférieurs
Résumé Les artères digestives, et en particulier l'artère mésentérique inférieure (a. mesenterica inferior), jouent à l'état normal un rôle minime dans la vascularisation des membres inférieurs. Il n'en est pas de même en cas d'oblitération aorto-iliaque. Les anastomoses anatomiques entre le système artériel digestif et les artères du membre inférieur s'hypertrophient et, dans un cas sur 10, deviennent prédominantes.Dans cette étude, le trajet et les relations des collatérales des artères digestives et leurs anastomoses sont étudiés. Plusieurs voies collatérales sont possibles.相似文献
28.
Gamma irradiation alters bluetongue virus protein antigen. 总被引:1,自引:0,他引:1
Bluetongue virus (BTV) antigen, prepared for a monoclonal antibody (MAb)-based competitive enzyme-linked immunosorbent assay (C-ELISA), was exposed to 1, 2, 3, 4, 5 and 6 Mrad of gamma irradiation. The major group-specific BTV protein (VP7) reactive with the Mab was altered at higher doses of radiation, as revealed by immunoblotting studies. As well, a reduction in immunoreactivity was noted when irradiated antigen was used in the ELISA. 相似文献
29.
Boisgard S Moreau PE Descamps S Courtalhiac C Silbert H Moreel P Michel JL Levai JP 《Surgical and radiologic anatomy : SRA》2003,25(3-4):330-334
The epicondylar axis is a reliable reference to check the rotation of the femoral implant in total knee prostheses (TKPs). However, during the operation it seems easier to use the posterior condylar axis as a landmark. The angle between these two axes is called the posterior condylar angle (PCA). The aim of this study was to measure the PCA in arthritic knees to assess the reliability of the posterior condylar axis as a reference for the control of the rotation of the femoral implant and to look for correlation with other radiological measurements. This prospective study consisted of 103 arthritic knees (81 varus, 22 valgus) before a TKP had been done in 103 patients (75 women, 28 men). The assessment of the PCA was made by computed tomographic scanning (CT). The HKA, HKS and HKT angles were measured on the pangonogram. The posterior condylar axis was internally rotated with respect to the epicondylar axis. The average value for all the patients was 2.65° degrees with a range from 0° to 7°. The PCA was significantly increased in the valgus knees. There was no correlation between the angles on the pangonogram and the posterior condylar axis. While the preoperative assessment of the PCA by CT scanning is reliable, the results obtained indicate the marked variability in its value. If one wishes to use the posterior condylar axis as a guide for rotation, it is therefore necessary to assess the PCA for each patient using adjustable jigs according to the value obtained. No measurement on standard radiographs allowed an extrapolation of the value of the PCA, and CT scanning seems to be the preferable radiological examination.
Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Etude tomodensitométrique de l'angle condylien postérieur dans les genoux arthrosiques. Intérêt dans le positionnement en rotation de l'implant fémoral dans les prothèses totales de genou
Résumé L'axe épicondylien est une référence fiable pour le contrôle de la rotation de l'implant fémoral dans les prothèses totales de genou (PTG). Mais, lors de l'intervention, il semble plus facile d'utiliser l'axe condylien postérieur comme repère. L'angle entre ses deux axes est appelé angle condylien postérieur (ACP). Le but de cette étude était de mesurer l'ACP dans les genoux arthrosiques, d'évaluer la fiabilité de l'axe condylien postérieur comme référence pour le réglage de la rotation de l'implant fémoral, de rechercher une corrélation avec d'autres mesures radiologiques. Une étude prospective comportant 103 genoux arthrosiques (81 varus et 22 valgus), avant PTG a été effectuée, chez 103 patients (75 femmes et 28 hommes). L'évaluation de l'ACP a été faite par examen tomodensitométrique (TDM). Les angles HKA, HKS et HKT ont été mesurés sur le pangonogramme. L'axe condylien postérieur était en rotation interne par rapport à l'axe épicondylien. La valeur moyenne pour tous les patients était de 2.65°, avec des valeurs de 0 à 7°. La valeur de l'angle CP augmentait avec une différence significative dans le groupe des genu valgum. Il n'y avait pas de corrélation entre les angles du pangonogramme et l'ACP. Si l'évaluation pré-opératoire de l'ACP par TDM est fiable, les résultats obtenus mettent en évidence une variabilité importante de sa valeur. Il faut donc, si l'on veut utiliser l'axe condylien postérieur comme repère de rotation, évaluer pour chaque patient l'ACP, et utiliser un ancillaire réglable reportant la valeur obtenue. Aucune mesure sur des radiographies standard ne permettant d'extrapoler la valeur de l'ACP, la TDM semble l'examen radiologique de choix.相似文献
30.
J Y Scoazec A Moreau M Maurice N Hassan G Feldmann 《Laboratory investigation; a journal of technical methods and pathology》1990,62(4):459-466
Certain markers used in the diagnosis and monitoring of human adenocarcinomas, such as carcinoembryonic antigen are membrane glycoproteins normally absent from the serum. How those proteins may reach the blood after the neoplastic transformation remains debated. In this work, we show that cholangiocarcinoma induced by 3'-methyl-4-dimethylaminoazobenzene in the rat provides some insight into the mechanisms implicated in this process. We observed that the extracellular matrix of all cholangiocarcinomas tested contained large amounts of a glycoprotein identified by a monoclonal antibody termed B10, and previously characterized as an integral membrane protein normally restricted to the apical domain of epithelial cell plasma membrane. The extracellular deposition of the B10-binding glycoprotein in cholangiocarcinomas was associated with the appearance of detectable levels of the protein in the serum, and an abnormal membrane expression of the protein, which was detected on both apical and basal plasma membrane domains of neoplastic biliary cells. We postulate that neoplastic transformation of biliary cells leads to an inappropriate membrane expression of the B10-binding protein, which in turn, results in the extracellular release of the protein and in its diffusion into the blood. The characteristic desmoplastic stroma of cholangiocarcinoma offers the opportunity to easily visualize the release process. A comparable mechanism is likely to explain how certain membrane glycoproteins used as serum markers in human malignancy may reach the blood. 相似文献