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991.

Introduction

Renal insufficiency, as evidenced by an increase in creatinine, is associated with higher mortality in patients with acute heart failure (AHF). Conversely, hemoconcentration (HC) in AHF is associated with lower mortality, but can also cause an increase in creatinine. Our aim was to assess the prognosis of HC in patients hospitalized for AHF presenting with or without worsening renal function (WRF).

Methods

A total of 618 consecutive patients admitted for AHF were included. WRF was defined according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria and HC was defined as an elevation of hemoglobin during hospitalization compared to the admission value. Six-month all-cause mortality was analyzed.

Results

The patients’ mean age was 79±11 years; 58% were women. Mortality at six months was 38% and 49% of patients had WRF. HC occurred in 38.9% of patients with WRF and was associated with improved survival (HR 1.6, 95% CI 1.10-2.34; p=0.02) compared to WRF without HC. HC was associated with better survival in KDIGO stages 1 and 2 (HR 1.8; 95% CI 1.1-2.8; p=0.01). For patients without chronic kidney disease (CKD) with WRF in stages 1 and 2, HC was associated with significantly better survival (HR 2.3; 95% CI 1.2-4.2; p=0.01).

Conclusion

In patients admitted for AHF without renal failure or CKD, WRF with HC is associated with a better prognosis, similar to that of patients without WRF, and should therefore be reclassified as ‘pseudo-WRF’.  相似文献   
992.
993.
Objectives: To evaluate the possible relationship between aminotransferases levels and markers of oxidative stress in chronic hepatitis C patients. Design and methods: Patients without treatment for hepatitis were divided in to group I (15–39 U/L); group II (41–76 U/L) and group III (81–311 U/L) of activity alanine aminotransferase (ALT). Blood markers of oxidative stress [catalase (CAT), glutathione peroxidase (GPx), thiobarbituric acid‐reactive species (TBARS), nonprotein and protein thiol (NP‐SH and P‐SH) groups and vitamin C] were determined. Results: P‐SH and NP‐SH levels, TBARS, GPx and CAT were not different between groups. Vitamin C was significantly decreased in groups II (P=0.03) and III (P=0.001) when compared with group I and correlated negatively with aspartate aminotransferase (AST; r=?0.29, P=0.042). Conclusion: Vitamin C levels were negatively associated with AST, suggesting that vitamin C could be an additional indicator of hepatitis C severity.  相似文献   
994.
Background and Objective High levels of some adipocytokines have been reported in patients with chronic renal failure, but little information is available on adipocytokine concentrations in uraemic patients under different modalities of therapy. Our aims were (1) to quantify the serum concentrations of leptin, adiponectin and resistin in uraemic patients on peritoneal dialysis (PD) and haemodialysis (HD), in comparison with patients on conservative management, and (2) to study the relationships between adipocytokine levels and previous atherosclerotic vascular disease. Patients and Measurements We studied 82 dialysis patients treated by PD (n = 44, 23 males and 21 females, mean age 54·4 ± 1·8 years) or HD (n = 38, 22 males and 16 females, age 60·8 ± 1·6 years). A group of 19 uraemic patients on conservative management served as the control. Serum concentrations of leptin, adiponectin and resistin were measured in all subjects. Information on vascular disease (cerebral vascular, peripheral vascular and heart disease) was obtained from a detailed medical history. Results PD patients showed significantly higher serum leptin concentrations [median (interquartile range), 28·7 (13·0–71·9) µg/l] than those found in patients on HD [9·7 (4·7–31·9) µg/l, P < 0·01] or in conservative management [5·9 (4·3–38·6) µg/l, P < 0·05]. Adiponectin concentrations were similar in the three groups of patients (mean ± SEM, 48·0 ± 4·5 mg/l in PD, 57·7 ± 4·4 mg/l in HD, and 44·4 ± 7·0 mg/l in controls, NS). Patients treated by both PD and HD exhibited resistin concentrations significantly higher than those found in controls (26·3 ± 0·99 and 27·5 ± 1·4 µg/l, respectively, vs. 17·3 ± 1·0 µg/l, P < 0·001). Leptin concentrations were positively correlated with body mass index (BMI) (r = 0·287, P < 0·01) and adiponectin levels were negatively related to BMI (r = ?0·416, P < 0·001) and the homeostatic model assessment (HOMA‐R) index (r =?0·216, P < 0·05). Leptin, adiponectin and resistin levels in patients with previous vascular events were similar to those found in patients without these complications. Logistic regression analysis did not demonstrate any relationship between serum adipocytokine concentrations and the presence of vascular disease of any type. A significant relationship between resistin and heart disease [odds ratio (OR) 1·80 (1·03–3·15), P = 0·039] was found when analysing subgroups of patients. Conclusions These data suggest that leptin levels are higher in PD patients, and resistin levels are higher in PD and HD patients in relation to patients on conservative management, whereas adiponectin concentrations are similar in the three groups. These results do not support the presence of a clinically relevant relationship between adipocytokines and previous episodes of vascular disease in the whole population or in patients classified in subgroups, with the only exception of a relationship between resistin levels and heart disease.  相似文献   
995.

Introduction

Immune response to vaccination in infants born prematurely may be lower than in infants born at full-term. Some clinical factors might be associated with humoral immune response.

Objectives

The objectives of this study were to compare the immune response to measles and varicella vaccination in infants born prematurely with those born at full-term and to analyze factors associated with measles and varicella antibody levels.

Methods

Prospective study including two groups of infants aged 12 months. One group of infants born prematurely with birth-weight <1500 g and who were in follow-up at the outpatient clinic for preterm infants at the institution and other group of infants born at full-term. Infants with malformations, primary immunodeficiency diseases, born to HIV-positive mothers or who had received plasma or immunoglobulin transfusions five months before or three weeks after vaccination were excluded. Plasma antibodies were measured by ELISA and factors associated with antibody levels were assessed by linear regression.

Results

Sixty-five premature and 56 full-term infants were included. The percentage of immune individuals after vaccination against measles (100% vs. 100%) and varicella (92.5% vs. 93.2%) were similar in both groups, as well as the antibody levels against measles (2.393 vs. 2.412 UI/mL; p = 0.970) and varicella (0.551 vs. 0.399 UI/mL; p = 0.114). Use of antenatal corticosteroids decreased measles antibody levels whereas breastfeeding for more than six months increased varicella antibody levels.

Conclusions

Humoral responses to measles and varicella were similar between infants born prematurely and full-term infants. Measles antibody levels were negatively associated with antenatal corticosteroid use; varicella antibodies were positively associated with prolonged breastfeeding.  相似文献   
996.
997.
There is a high level of genetic diversity among the clinical isolates of the taxon Trypanosoma cruzi. The results of recent studies on well defined gene loci have revealed that T. cruzi can be divided into two major phylogenetic lineages, designated T. cruzi I and T. cruzi II. Further intra-lineage polymorphisms were explored, in clinical isolates from five representative regions of Brazil, using the internal transcribed spacers that flank the 5.8S ribosomal RNA gene. These regions were amplified in a PCR and the products were digested with six restriction enzymes before being subjected to RFLP analysis in polyacrylamide gels. The results were used to construct a complex evolutionary tree, in which the isolates were clustered into two major phylogenetic lineages with a low level of similarity. To investigate the evolutionary relationships between the isolates, the PCR products were cloned and sequenced. The results of the subsequent phylogenetic analysis confirmed the presence of the two major groups of T. cruzi and showed that zymodeme 3, a third iso-enzymatic sub-group, is closer to T. cruzi I than to T. cruzi II.  相似文献   
998.
999.
Determination of plasma and tissue cytokinelevels in inflammatory bowel disease have frequentlyresulted in conflicting data. In the present study wedetermined in patients with ulcerative colitis (UC), the levels of the proinflammatory cytokinesinterleukin (IL)-1, IL-6, interferon(IFN)-, and tumor-necrosis factor (TNF)-liberated by peripheral blood mononuclear cells (PBMC)and lamina propria mononuclear cells (LPMC) after 48-hrculture with pokeweed mitogen (PWM). IL-1, IL-6,IFN- and TNF- in the supernatant weredetected by ELISA. Results show low basal levels ofIL-1 secretion by PBMC and LPMC, and a considerableincrease after mitogen stimulation. Basal IL-6production by PBMC was higher in UC patients than incontrols [2029 pg/ml, CI9 (–165 to4223) vs 572 pg/ml (–383 to 1527) respectively, P = 0.05] and also afterPWM activation [14,995 pg/ml (7759 -22230) vs 6598 pg/ml(3240-9956), respectively, P = 0.05]. In LPMC, nodifferences in IL-6 secretion were observed. TNF- in activated PBMC of patients with UC was notsignificantly increased in relation to control (P =0.09). No constitutive secretion of IFN- wasobserved in mononuclear cells. IFN- levelssecreted by activated LPMC were lower in patients withUC than in controls [1571 pg/ml (–108 to 3251) vs7953 pg/ml (3851-12,055), respectively, P = 0.03]. Theseresults suggest that IL-6, IL-1, and TNF- participate as mediators in the inflammatoryphenomena observed in UC. Further studies are necessaryto evaluate the role of IFN- in thiscondition.  相似文献   
1000.
Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.  相似文献   
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