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41.
BackgroundComputed Tomography (CT) Pulmonary Angiography is the most commonly used diagnostic study for acute pulmonary embolism (PE). Echocardiogram (ECHO) is also used for risk stratification in acute PE, however the diagnostic performance of CT versus ECHO for risk stratification remains unclear.MethodsCT and ECHO right ventricle (RV) and left ventricle (LV) diameters were measured in a retrospective cohort of patients with acute PE. RV:LV diameter ratios were calculated and correlation between CT and ECHO RV:LV ratio was assessed. Sensitivity and specificity for the composite adverse events endpoint of mortality, respiratory failure requiring intubation, cardiac arrest, or shock requiring vasopressors within 30 days of admission were assessed for CT or ECHO derived RV:LV ratio alone and in combination with biomarkers (troponin or B-type natriuretic peptide).ResultsA total of 74 subjects met the inclusion criteria and had a mean age of 62±18 years. The proportion of patients with RV:LV >1 was similar when comparing CT (37.8%) versus ECHO (33.8%) (P = 0.61). A statistically significant correlation was found between CT derived and ECHO derived RV:LV diameter ratio (r = 0.832, P < 0.001). The sensitivity and specificity to predict 30-day composite adverse events for CT versus ECHO derived RV:LV diameter ratio >1 together with positive biomarker status was similar with sensitivity and specificity of 87% and 41% versus 87% and 42%, respectively.ConclusionsIn patients with acute PE, CT and ECHO RV:LV diameter ratio correlate well and identify similar proportion of PE patients at risk for early adverse events. These findings may streamline risk stratification of patients with acute PE.  相似文献   
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目的:探讨不同剂量的1,25(OH)2D3对大鼠抗胸腺细胞抗体(Thy1)肾炎系膜细胞凋亡的影响。方法将SD大鼠120只分为空白对照组(A组)、肾炎模型组(B组)、低剂量1,25(OH)2D3组(C组)和高剂量1,25(OH)2D3组(D组),每组30只。C、D两组造模成功后给药干预,4组分别于干预后第1、3、7、14、21天每组随机处死6只大鼠,取肾组织标本经HE及PAS染色后确定肾脏病理损害分级;免疫组化法检测肾组织中半胱氨酸天冬氨酸蛋白酶3(Caspase‐3)的表达;TUNEL试剂盒检测其肾小球内细胞凋亡。结果与A组比较,B组Caspase‐3表达增强(P<0.05);与B组比较,C、D组Caspase‐3表达增强,但差异无统计学意义(P>0.05);D组表达最高,但与C组比较差异无统计学意义(P>0.05)。与A组比较,B组肾小球内凋亡细胞明显增多(P<0.05),且随时间推移逐渐增强;与B组比较,C、D两组凋亡明显增多(P<0.05),并在3d达高峰,7、14d逐渐下降,21d趋于正常(P<0.05);C、D两组比较,D组凋亡细胞增多明显,但差异无统计学意义(P>0.05)。结论1,25(OH)2D3具有诱导大鼠肾小球系膜细胞凋亡的作用,其参与了对Caspase‐3的调节,诱导系膜细胞凋亡,促进肾炎的修复,可延缓肾脏疾病进展。  相似文献   
45.

Objective

To determine the impact of long-term, body weight–supported locomotor training after chronic, incomplete spinal cord injury (SCI), and to estimate the health care costs related to lost recovery potential and preventable secondary complications that may have occurred because of visit limits imposed by insurers.

Design

Prospective observational cohort with longitudinal follow-up.

Setting

Eight outpatient rehabilitation centers that participate in the Christopher & Dana Reeve Foundation NeuroRecovery Network (NRN).

Participants

Individuals with motor incomplete chronic SCI (American Spinal Injury Association Impairment Scale C or D; N=69; 0.1–45y after SCI) who completed at least 120 NRN physical therapy sessions.

Interventions

Manually assisted locomotor training (LT) in a body weight–supported treadmill environment, overground standing and stepping activities, and community integration tasks.

Main Outcome Measures

International Standards for Neurological Classification of Spinal Cord Injury motor and sensory scores, orthostatic hypotension, bowel/bladder/sexual function, Spinal Cord Injury Functional Ambulation Inventory (SCI-FAI), Berg Balance Scale, Modified Functional Reach, 10-m walk test, and 6-minute walk test. Longitudinal outcome measure collection occurred every 20 treatments and at 6- to 12-month follow-up after discharge from therapy.

Results

Significant improvement occurred for upper and lower motor strength, functional activities, psychological arousal, sensation of bowel movement, and SCI-FAI community ambulation. Extended training enabled minimal detectable changes at 60, 80, 100, and 120 sessions. After detectable change occurred, it was sustained through 120 sessions and continued 6 to 12 months after treatment.

Conclusions

Delivering at least 120 sessions of LT improves recovery from incomplete chronic SCI. Because walking reduces rehospitalization, LT delivered beyond the average 20-session insurance limit can reduce rehospitalizations and long-term health costs.  相似文献   
46.
Apart from its classical function in bone and calcium metabolism, vitamin D is also involved in immune regulation and has been linked to various cancers, immune disorders and allergic diseases. Within the innate and adaptive immune systems, the vitamin D receptor and enzymes in monocytes, dendritic cells, epithelial cells, T lymphocytes and B lymphocytes mediate the immune modulatory actions of vitamin D. Vitamin D insufficiency/deficiency early in life has been identified as one of the risk factors for food allergy. Several studies have observed an association between increasing latitude and food allergy prevalence, plausibly linked to lower ultraviolet radiation (UVR) exposure and vitamin D synthesis in the skin. Along with mounting epidemiological evidence of a link between vitamin D status and food allergy, mice and human studies have shed light on the modulatory properties of vitamin D on the innate and adaptive immune systems. This review will summarize the literature on the metabolism and immune modulatory properties of vitamin D, with particular reference to food allergy.  相似文献   
47.
目的:通过检测川崎病(KD)急性期血清25-羟维生素D3[25-(OH)D3]水平及T细胞亚群,探讨其与KD冠脉损害的关系及可能机制。方法选取西安市儿童医院的KD患儿35例为病例组,依据心脏超声检查结果分为冠脉损害组(CAL)9例和非冠脉损害组( NCAL)26例;选取正常查体儿童25例为对照组。分别检测其急性期血清25-( OH) D3值;同期检测CAL组及NCAL组T淋巴细胞亚群,并对结果进行分析。结果 CAL组血清25-( OH) D3水平明显高于NCAL组,经比较有显著性差异(t=3.681,P=0.001)。 CAL组CD4/CD8明显高于NCAL组,经比较亦有显著性差异(t=2.032,P=0.050)。结论25-(OH) D3参与KD冠脉损害的发生,可能与其影响T细胞亚群分布有关。  相似文献   
48.
The effect of a perfectly conducting sphere simulating the intracavitary blood mass on a dipole source located at the interface with the outer tissue (myocardium) is studied, utilizing image theory. The resulting enhancement factor is found to be a function of the field point location and is not a constant, as previously reported by Brody and by Rush and Nelson.  相似文献   
49.
A patient manifesting the arthropathy of hemochromatosis without abnormal serum iron studies is described. Hemochromatosis was confirmed by liver biopsy. This case serves to emphasize the diagnostic value of the characteristic arthropathy of hemochromatosis. Our observations in this patient support the hypothesis that the pathogenesis of hereditary hemochromatosis differs from that of acquired iron overload states. The concurrent presence of hypouricemia is explored in this patient and in 18 other patients with hereditary hemochromatosis. Men with hereditary hemochromatosis were found to have lower serum uric acid levels than expected. In our patient, a renal defect in tubular reabsorption of uric acid appears responsible for hypouricemia.The apparent association of hemochromatosis and hypouricemia deserves further investigation.  相似文献   
50.
We previously demonstrated that treatment with indomethacin in vivo significantly blunted the glucagon-induced glycemic response in the rat. This prostaglandin synthetase (cyclo-oxygenase) inhibitor also accentuated the evanescent effect of glucagon on hepatic glucose output in the intact, anesthetized rat. In this report, we present evidence that impairment of glucagon action in the rat liver by indomethacin is mediated through its inhibitory effect on both cAMP-dependent and cAMP-independent hepatic protein kinase. Indomethacin treatment did not have a measurable effect on any of the other components of the glucagon transducer system. Furthermore, infusion with glucagon for two hours that maintained plasma glucagon values at high physiological levels significantly reduced hepatic cAMP-dependent protein kinase activity without altering its Km. Glucagon infusion also down-regulated its own hepatic receptors and glucagon-stimulated cAMP production; prostaglandin E1-stimulated cAMP production was not affected. We concluded that prostaglandins may play a role in the regulation of hepatic protein kinases involved in the glucagon-stimulated glycogenolytic response and that glucagon-induced down-regulation extends at least to the hepatic protein kinases. However, a direct effect of indomethacin or protein kinase and the adenylate cyclase complex cannot be ruled out.  相似文献   
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