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951.
Role of capsule endoscopy in alarm features and non‐responsive celiac disease: A European multicenter study 下载免费PDF全文
Enrique Perez‐Cuadrado‐Robles Marisol Lujan‐Sanchis Luca Elli Jose‐Francisco Juanmartinena‐Fernandez Javier Garc?a‐Lledo Luc?a Ruano‐D?az Juan Egea‐Valenzuela Victoria‐Alejandra Jimenez‐Garc?a Federico Arguelles‐Arias Mileidis San Juan‐Acosta Cristina Carretero‐Ribon Noelia Alonso‐Lazaro Bruno Rosa Francisco Sanchez‐Ceballos Antonio Lopez‐Higueras Ignacio Fernandez‐Urien‐Sainz Federica Branchi Julio Valle‐Mu?oz Pilar Borque‐Barrera Santiago Gonzalez‐Vazquez Vicente Pons‐Beltran Sof?a Xavier Begona Gonzalez‐Suarez Juan‐Manuel Herrer?as‐Gutierrez Enrique Perez‐Cuadrado‐Mart?nez Javier Sempere‐Garc?a‐Arguelles Enteroscopy Capsule Endoscopy Spanish Society Group of the Spanish Society of Digestive Endoscopy 《Digestive endoscopy》2018,30(4):461-466
952.
953.
Raphael JF Felizardo ;Niels OS Cmara 《World journal of gastroenterology : WJG》2013,19(24):3723-3725
Ochratoxin A (OTA) is a secondary metabolite of Asper-gillus and Penicillium, microorganisms that can be haz-ardous to health when present as food contaminants. OTA is a potent member of a group of mycotoxins. Prolonged exposure to mycotoxins in the diet is related to cancer, among other diseases. Hepatocellular car-cinoma (HCC) accounts for 70%-90% of primary liver cancers and is the third leading cause of cancer-related deaths worldwide. In a recent study, Ibrahim et al proposed a correlation between the incidence of HCC and contamination with OTA. Analysis of OTA in serum samples showed that HCC patients had the highest incidence of OTA of the subjects examined (5-fold higher than that of the control group). OTA levels were significantly increased in HCC patients. This study demonstrates that chronic exposure to high levels of OTA may be associated with a high risk of liver cancer development. Future epidemiologic studies of HCC should focus on good practices in food preparation, food storage and the consumption of OTA-containing foods. 相似文献
954.
955.
Gallot G; Hallet MM; Gaschet J; Moreau JF; Vivien R; Bonneville M; Milpied N; Vie H 《Blood》1996,88(3):1098-1103
Allogeneic bone marrow transplantation is still limited by the morbidity and mortality caused by graft-versus-host disease (GVHD), resulting from host recognition by donor T lymphocytes. It is possible to drastically reduce the T-cell content of the graft. However, transplanted T cells can also have a beneficial effect by graft enhancement and the graft-versus-leukemia effect. How can we keep the beneficial GVL effect while protecting the patient from possible GVHD? A recent report proposed the ex vivo transfer of the herpes simplex thymidine kinase (HSv-tk) gene into donor T cells before their infusion with hematopoietic stem cells. This procedure is expected to allow selective donor T-cell depletion with ganciclovir should GVHD occur, but it has two major drawbacks: reinjection of a fraction of untransfected T cells cannot be avoided and heterogeneity of the transfected population results in increased risks such as HSv-tk gene instability or dysfunction of some of the transfected T cell. Alternative approaches must be considered. We demonstrate here the feasibility of generating HSv-tk transfected HLA-specific CD4+ cytotoxic T-cell clonal populations, in which 100% of the cells have the HSv-tk gene inserted at a single site within their genome. These clones retained their specificity, their function, and their sensitivity to ganciclovir treatment. Our approach is not limited to bone marrow transplantation. Indeed, this procedure represents a useful alternative to retroviral gene transduction and is applicable to every circumstance where clinical use of gene modified T-cell clones is to be considered. 相似文献
956.
The gamma-delta-beta-globin gene region in G gamma-beta +-hereditary persistence of fetal hemoglobin 总被引:5,自引:0,他引:5
We report restriction endonuclease analysis of the gamma-delta-beta- globin gene region in a mother and child heterozygous for G gamma-beta +-hereditary persistence of fetal hemoglobin (HPFH). The affected chromosome in these persons directs the production of G gamma-chains and beta-chains but not A gamma-chains. DNA was digested with several restriction enzymes and was examined for gamma, delta, beta sequences by blot hybridization. Only normal digestion fragments were present. By sensitive methods, we were unable to detect a deletion in the entire gamma-delta-beta-globin gene region of the affected chromosome, indicating that in this family, G gamma-beta +-HPFH is not due to a large deletion. 相似文献
957.
Systemic, regional and cerebral hemodynamic effects of a new angiotensin converting enzyme inhibitor, imidapril, in healthy volunteers 总被引:1,自引:0,他引:1
P. Démolis D. Annane P. Duhazé and JF Giudicelli 《Fundamental & clinical pharmacology》1994,8(1):80-89
Summary— The effects of two single oral doses (5 mg and 20 mg) of a new angiotensin I-converting enzyme inhibitor, imidapril, on a) systemic hemodynamics (arterial pressure, heart rate, cardiac output), b) brachial and common carotid arteries' hemodynamics (diameter and blood flow, pulsed Doppler technique), c) cerebral hemodynamics (middle cerebral artery mean blood flow velocity, transcranial Doppler technique), and d) biological parameters (plasma converting enzyme activity, active plasma renin, plasma aldosterone, catecholamines, and atrial natriuretic factor) were investigated and compared with those of a placebo during the 24 h period following administration in a randomized, double-blind, cross-over study performed in six healthy volunteers. Imidapril induced a strong, dose-dependent and sustained inhibition of plasma converting enzyme activity and at the 20 mg dose an increase in active plasma renin. Other investigated biological parameters were not drug-affected. Imidapril, whatever the dose, did not significantly affect systemic hemodynamic parameters. Imidapril, 20 mg, significantly increased common carotid artery blood flow and diameter and brachial artery diameter. Brachial blood flow also tended to increase but this was not significant. The middle cerebral artery mean blood flow velocity investigated in only five volunteers, underwent spontaneous variations after placebo, and these variations were not affected by imidapril, suggesting that imidapril, whatever the dose, does not influence cerebral blood flow. Thus, imidapril's vasodilating properties apparently affect only the muscular (brachial artery) and cutaneous (external carotid artery) territories, but do not influence the cerebral vascular bed. 相似文献
958.
Pauline Henrot Jennifer Foret Thomas Barnetche Estibaliz Lazaro Pierre Duffau Julien Seneschal Thierry Schaeverbeke Marie-Elise Truchetet Christophe Richez 《Joint, bone, spine : revue du rhumatisme》2018,85(2):155-163
Objectives
To determine whether subclinical atherosclerosis is increased in patients with systemic lupus erythematosus (SLE) compared to healthy individuals, using carotid intima-media thickness (CIMT), carotid plaque (CP) presence or flow-mediated dilatation (FMD).Methods
A systematic literature search was performed using MedLine, Embase and Cochrane databases. Two reviewers independently screened the articles to identify studies that compared the rates of atherosclerosis in SLE patients versus healthy controls. The results were pooled in a meta-analysis. Factors influencing the CIMT, CP or FMD results were collected.Results
Of the 203 articles initially identified, 68 were selected for the meta-analysis. Compared to healthy controls, SLE patients had a significantly increased CIMT (mean difference [MD] of 0.08 mm, 95% CI [0.06–0.09], P < 0.05), more CP (odds ratio 2.01, 95% CI [1.63–2.47], P < 0.05) and decreased FMD (MD ?3.96%, 95% CI [?5.37 to ?2.54)], P < 0.05). There was marked heterogeneity among the studies. However, the results of the meta-analysis that included only the CIMT per new international recommendations also showed an increased CIMT in SLE patients, but the heterogeneity was low (MD 0.04 mm, 95% CI [0.02–0.06], P < 0.05; I2 = 23%).Conclusion
SLE patients exhibit increased subclinical atherosclerosis compared to healthy controls. CIMT is a promising measure for cardiovascular risk evaluations because non-invasive, non-radiation-based, reproducible. Thus, CIMT can be proposed as an alternative to the reliable CP evaluation and to FMD, which is influenced by independent factors such as smoking. Future studies should focus on reducing the heterogeneity of these measures using standardized procedures. 相似文献959.
目的:了解白来航笼养蛋鸡胰岛素样生长因子Ⅰ限制性片断多态性与骨质疏松症的关系。方法:实验于2006-01/04在南京农业大学畜禽骨骼研究实验室完成。随机选取83周龄白来航蛋鸡180羽,应用PCR扩增鸡胰岛素样生长因子Ⅰ启动子上游7kb处基因片断,用PstⅠ限制性内切酶消化产生限制性片断长度多态性,分析胰岛素样生长因子Ⅰ多态性与胫骨、股骨、肱骨骨放射密度及其皮质骨厚度、髓质骨和小梁骨体积、体质量、骨代谢标志物(钙、磷、骨钙素及碱性磷酸酶)、雌二醇等的关系。结果:180羽蛋鸡PP、Pp、pp基因型频率分别为0.0389、0.35、0.611,P、p等位基因频率分别为0.214、0.786。方差分析(ANOVA)显示,pp基因型肱骨骨放射密度及皮质骨厚度显著大于Pp、PP基因型(P<0.05)、pp基因型的胫骨皮质骨厚度极显著大于PP基因型(P<0.01),pp基因型胫骨骨骺骨小梁体积极显著大于Pp、PP基因型(P<0.01)。结论:白来航笼养蛋鸡胰岛素样生长因子Ⅰp等位基因具有一定的骨质指针作用,pp基因型蛋鸡呈现骨质强的优势,提示从分子水平探讨骨质丢失以及对骨质疏松症的基因诊断和抗性基因选育具有一定的意义。 相似文献
960.
Sparfloxacin but not levofloxacin or ofloxacin prolongs cardiac repolarization in rabbit Purkinje fibers 总被引:1,自引:0,他引:1
MM Adamantidis BM Dumotier JF Caron and R Bordet 《Fundamental & clinical pharmacology》1998,12(1):70-76
Summary— Sparfloxacin, a fluoroquinolone antibacterial, has been reported to prolong cardiac repolarization in some patients. In this study, we have investigated the in vitro cardiac electrophysiological effects of two other fluoroquinolones, levofloxacin and ofloxacin, and compared them with those exerted by Sparfloxacin. Cardiac action potentials have been recorded from rabbit Purkinje fibers using conventional glass microelectrodes. The influence of a sudden decrease in stimulation rate on repolarization is examined. It is found that ofloxacin and levofloxacin (1–100 μM) do not alter the action potential parameters even at a concentration as high as 100 μM. The stimulation rate is without effect on repolarization. On the contrary, Sparfloxacin (1–100 μM) lengthens concentration-dependently the duration of action potential, this effect being significant from the concentration of 10 μM. A non significant decrease in maximal rate of rise of phase 0 depolarization was observed at the concentration of 100 μTM. Under low stimulation rate, the sparfloxacin-induced prolonging effect was magnified and early afterdepolarizations occurred in one of seven fibers from the concentration of 30 μM and in four other fibers at the concentration of 100 μM. These results suggest that levofloxacin and ofloxacin had no effect on cardiac cellular electrophysiology whereas Sparfloxacin exerts pure class III electrophysiological effects, which can explain the prolongation of QT interval observed clinically in some patients and might become arrhythmogenic in the presence of other predisposing factors. 相似文献