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991.
Background Anal inspection and digital rectal examination are routinely performed in fecal incontinent patients but it is not clear to what extent they contribute to the diagnostic work-up. We examined if and how findings of anal inspection and rectal examination are associated with anorectal function tests and endoanal ultrasonography. Methods A cohort of fecal incontinent patients (n=312, 90% females; mean age 59) prospectively underwent anal inspection and rectal examination. Findings were compared with results of anorectal function tests and endoanal ultrasonography. Results Absent, decreased and normal resting and squeeze pressures at rectal examination correlated to some extent with mean (±SD) manometric findings: mean resting pressure 41.3 (±20), 43.8 (±20) and 61.6 (±23) Hg (p<0.001); incremental squeeze pressure 20.6 (±20), 38.4 (±31) and 62.4 (±34) Hg (p<0.001). External anal sphincter defects at rectal examination were confirmed with endoanal ultrasonography for defects <90 degrees in 36% (37/103); for defects between 90-150 degrees in 61% (20/33); for defects between 150-270 degrees in 100% (6/6). Patients with anal scar tissue at anal inspection had lower incremental squeeze pressures (p=0.04); patients with a gaping anus had lower resting pressures (p=0.013) at anorectal manometry. All other findings were not related to any anorectal function test or endoanal ultrasonography. Conclusions Anal inspection and digital rectal examination can give accurate information about internal and external anal sphincter function but are inaccurate for determining external anal sphincter defects <90 degrees. Therefore, a sufficient diagnostic work-up should comprise at least rectal examination, anal inspection and endoanal ultrasonography.  相似文献   
992.
BACKGROUND/AIMS: The agonistic Jo2 anti-Fas antibody reproduces human fulminant hepatitis in mice. We tested the hypothesis that enhancing hepatic glutathione (GSH) stores may prevent Jo2-induced apoptosis. METHODS: We fed mice with a normal diet or a sulfur amino acid-enriched (SAA(+)) diet increasing hepatic GSH by 63%, and challenged these mice with Jo2. RESULTS: The SAA(+) diet markedly attenuated the Jo2-mediated decrease in hepatic GSH and the increase in the oxidized glutathione (GSSG)/GSH ratio in cytosol and mitochondria. The SAA(+) diet prevented protein kinase Czeta (PKCzeta) and p47(phox) phosphorylations, Yes activation, Fas-tyrosine phosphorylation, Bid truncation, Bax, and cytochrome c translocations, the mitochondrial membrane potential collapse, caspase activation, DNA fragmentation, hepatocyte apoptosis, and mouse lethality after Jo2 administration. The protective effect of the SAA(+) diet was abolished by a small dose of phorone decreasing hepatic GSH back to the levels observed in mice fed the normal diet. Conversely, administration of GSH monoethyl ester after Jo2 administration prevented hepatic GSH depletion and attenuated toxicity in mice fed with the normal diet. CONCLUSIONS: The SAA(+) diet preserves GSSG/GSH ratios, and prevents PKCzeta and p47(phox) phosphorylations, Yes activation, Fas-tyrosine phosphorylation, mitochondrial permeabilization, and hepatic apoptosis after Fas stimulation. GSH monoethyl ester is also protective, suggesting possible clinical applications.  相似文献   
993.
Semicarbazide-sensitive amine oxidase (SSAO)-deficient mice present no alteration in elastin cross-linking processes and carotid mechanical properties. In contrast, previous studies have shown that SSAO inhibitors induced marked anomalies in arterial structure and function. The aim of the present study was to examine the effect of semicarbazide (SCZ), an efficient SSAO inhibitor, on the arterial phenotype of the carotid artery in relation to modulation of SSAO and lysyl oxidase activities in growing rats. We first show that after 6 weeks of SCZ treatment (100 mg/kg per day), SSAO activity was reduced by 90%, whereas lysyl oxidase activity was only partially inhibited (<60%) in carotid artery, compared with controls. There was significant growth inhibition and no difference in mean arterial pressure but an increase in pulse pressure with a smaller arterial diameter in SCZ-treated rats. SCZ decreased aortic insoluble elastin without a change in total collagen. In addition, extracellular proteins other than insoluble elastin and collagen were increased in SCZ-treated rats. All of the elastic lamellae presented globular masses along their periphery, and focal disorganization was observed in the ascending aorta. Carotid artery mechanical strength was lower in SCZ-treated rats, and the elastic modulus-wall stress curve was shifted leftward compared with controls, indicating increased stiffness. Thus, SCZ modifies arterial geometry and mechanical properties, alters elastic fiber structure, and reduces the content of cross-linked elastin. Because these abnormalities are essentially absent in SSAO-deficient mice, our results suggest that lysyl oxidase inhibition is responsible for the major part of the vascular phenotype of SCZ-treated rats.  相似文献   
994.
BACKGROUND: The cardiovascular effects of sulfonylureas (SU) in diabetic patients are controversial and it has been suggested that diabetic patients with acute myocardial infarction while on SU were at increased risk. OBJECTIVES: To assess the in-hospital outcome of patients with acute myocardial infarction according to the use of SU at the time of the acute episode. METHODS: Of 443 intensive care units in France, 369 (83%) prospectively collected all cases of infarction admitted within 48 h of symptom onset in November 2000. RESULTS: Among the 2320 patients included in the registry, 487 (21%) had diabetes, of whom 215 (44%) were on SU. Patients on SU were older and had a more frequent history of hyperlipidemia than those not receiving SU. Type and location of infarction were similar in the two groups, and there was no difference in Killip class on admission. In-hospital mortality was lower in patients on SU (10.2%) than in those without SU (16.9%) (p = 0.035). There was a trend toward less frequent ventricular fibrillation (2.3% vs 5.9%, p = 0.052). In two models of multivariate analyses, SU therapy was associated with decreased in-hospital mortality (model 1: relative risk: 0.44, p = 0.012; model 2: relative risk: 0.37, p = 0.020). CONCLUSIONS: In this nationwide registry reflecting real-world practice, the use of sulfonylureas in diabetic patients was not associated with increased in-hospital mortality.  相似文献   
995.
Local/regional and systemic treatments of hepatocellular carcinoma   总被引:4,自引:0,他引:4  
Screening programs for patients with cirrhosis are designed to detect hepatocellular carcinoma at an early stage when effective treatment is feasible and may provide long-term survival benefits. However, only a minority of these patients will be considered candidates for liver transplantation or surgical resection and hence, most cases will be evaluated for other medical options. While systemic therapy has never been shown to bear a relevant antitumoral activity with an impact on survival, there are several locoregional options that can achieve a high rate of objective responses (this includes complete necrosis or partial reduction in tumor burden). Percutaneous ablation by any of the available methods (ethanol injection, radiofrequency, microwave, acetic acid injection, laser) is extremely useful in patients with small solitary tumors. Results indicate that 90% of tumors < 2 cm will be completely ablated using the percutaneous approach. However, when tumor size exceeds 3 cm and/or the number of nodules is greater than 3, the rate of treatment success is significantly reduced. In patients with large/multifocal disease, the sole option that has been shown to provide treatment efficacy with moderate improvement in survival is chemoembolization. New therapeutic agents should target biological mechanisms in a tailored strategy, and the demonstration of beneficial results for patients should be obtained by large, randomized, controlled trials comparing active intervention versus no treatment.  相似文献   
996.
In heart failure (HF) a main factor in reduced contractility is reduced SR Ca2+ content and reversed force-frequency response (FFR), ie, from positive to negative. Our arrhythmogenic rabbit HF model exhibits decreased contractility mainly due to an increase in Na/Ca exchange (NCX) activity (with only modest decrease in SR Ca2+-ATPase (SERCA) function), similar to many end-stage HF patients. Here we test whether phospholamban (PLB) inhibition using a dominant-negative mutant PLB adenovirus (K3E/R14E, AdPLB-dn, with beta-galactosidase adenovirus as control) could enhance SERCA function and restore Ca2+ transients and positive FFR in ventricular myocytes from these HF rabbits. HF myocytes infected with AdPLB-dn (versus control) had enhanced Ca2+ transient amplitude (2.0+/-0.1 versus 1.6+/-0.05 F/Fo at 0.5 Hz, P<0.05) and had a positive FFR, whereas acutely isolated HF myocytes or those infected with Adbetagal had negative FFR. Ca2+ transients declined faster in AdPLB-dn versus Adbetagal myocytes (RT50%: 317+/-29 versus 551+/-90 ms at 0.5 Hz, P<0.05) and had an increased SR Ca2+ load (3.5+/-0.3 versus 2.6+/-0.2 F/Fo at 0.5 Hz, P<0.05), indicative of increased SERCA function. Furthermore, this restoration of function was not due to changes in NCX or SERCA expression. Thus, increasing SERCA activity in failing myocytes by AdPLB-dn gene transfer reversed the contractile dysfunction (and restored positive FFR) by increasing SR Ca2+ load. This approach could enhance contractile function in failing hearts of various etiologies, even here where reduced SERCA activity is not the main dysfunction.  相似文献   
997.
BACKGROUND: NOD2/CARD15, the first identified susceptibility gene in Crohn's disease (CD), is associated with ileal stenosis and increased frequency of surgery. Anti-Saccharomyces cerevisiae antibody (ASCA), a serological marker for CD, is associated with ileal location and a high likelihood for surgery. We hypothesized that the presence of ASCA and NOD2/CARD15 mutations could predict increased health care cost in CD. METHODS: CD patients in a prospectively designed community-based multinational European and Israeli cohort (n = 228) followed for mean 8.3 (SD 2.6) years had blood drawn for measurement of ASCA (IgG, IgA), Arg702Trp, Gly908Arg, and Leu1007fsinsC. Days spent in the hospital and the costs of medical and surgical hospitalizations and medications were calculated. RESULTS: The median duration of surgical hospitalizations was longer in Gly908Arg-positive than -negative patients, 3.5 and 1.5 days/patient-year (P < 0.01), and in ASCA-positive than -negative patients, 1.1 and 0 days/patient-year (P < 0.001). Median surgical hospitalization cost was 1,580 euro/patient-year in Gly908Arg-positive versus 0 euro/patient-year in -negative patients (P < 0.01), and 663 euro/patient-year in ASCA-positive versus 0 euro/patient-year in -negative patients (P < 0.001). Differences in cost of medications between groups were not significant. The effect of Gly908Arg was expressed in countries with higher Gly908Arg carriage rates. ASCA raised surgical costs independently of the age at diagnosis of disease. Arg702Trp and Leu1007fsinsC did not affect the cost of health care. CONCLUSIONS: Since CD patients positive for Gly908Arg and ASCA demonstrated higher health care costs, it is possible that measurement of Gly908Arg and ASCA at disease diagnosis can forecast the expensive CD patients.  相似文献   
998.
CONTEXT: The strong relationship between serum anti-Müllerian hormone (AMH) levels and the number of antral follicles supports the use of AMH measurements as a quantitative marker of the ovarian follicular status. Yet, it still is unclear whether the aptitude of an individual follicle to produce AMH reflects its reproductive competence. OBJECTIVE: This study examined the possible relationship between serum or follicular fluid (FF) AMH concentrations and the fate of the ensuing oocytes and embryos obtained by in vitro fertilization-embryo transfer conducted in monodominant follicle cycles. DESIGN AND SETTING: We conducted a prospective study at the University of Paris XI, Assistance Publique-H?pitaux de Paris, Institut National de la Santé et de la Recherche Médicale U782. PATIENTS: Patients included 118 infertile in vitro fertilization-embryo transfer candidates. INTERVENTIONS: Concentrations of AMH, progesterone, and estradiol were measured in the serum on cycle d 3 and on the day of oocyte pickup (dOPU), and in FF. Cycles were sorted into three sets of three distinct groups according to whether serum d 3, serum dOPU, and FF AMH concentrations were 30th centile or below (low AMH), between the 31st and the 70th centiles (average AMH), or above the 70th centile (high AMH) of measurements. MAIN OUTCOME MEASURE: Clinical pregnancy and embryo implantation rates were assessed. RESULTS: Clinical pregnancy rates (5.7, 20.0, and 39.5%, respectively; P < 0.002) and embryo implantation rates (11.8, 30.8, and 65.4, respectively; P <0.001) were markedly different among the low, moderate, and high FF AMH groups but not among the serum (d 3 or dOPU) AMH groups. Fertilization rates and embryo morphology remained similar irrespective of AMH concentrations in the serum or in FF. Incidentally, FF AMH concentrations were negatively correlated with FF progesterone (r = -0.27; P <0.003) and FF estradiol (r = -0.21; P <0.02) concentrations. CONCLUSIONS: Concentrations of AMH in the FF, but not in the serum, constitute a useful follicular marker of embryo implantation and are negatively related to FF progesterone and estradiol concentrations.  相似文献   
999.
Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretins secreted in response to oral glucose ingestion by intestinal L and K cells, respectively. The molecular mechanisms responsible for intestinal cell glucose sensing are unknown but could be related to those described for beta-cells, brain and hepatoportal sensors. We determined the role of GLUT2, GLP-1 or GIP receptors in glucose-induced incretins secretion, in the corresponding knockout mice. GLP-1 secretion was reduced in all mutant mice, while GIP secretion did not require GLUT2. Intestinal GLP-1 content was reduced only in GIP and GLUT2 receptors knockout mice suggesting that this impairment could contribute to the phenotype. Intestinal GIP content was similar in all mice studied. Furthermore, the impaired incretins secretion was associated with a reduced glucose-stimulated insulin secretion and an impaired glucose tolerance in all mice. In conclusion, both incretins secretion depends on mechanisms involving their own receptors and GLP-1 further requires GLUT2.  相似文献   
1000.
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