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91.
A novel TRIM family member, TRIM59 gene was characterized to be upregulated in SV40 Tag oncogene-directed transgenic and knockout mouse prostate cancer models as a signaling pathway effector. We identified two phosphorylated forms of TRIM59 (p53 and p55) and characterized them using purified TRIM59 proteins from mouse prostate cancer models at different stages with wild-type mice and NIH3T3 cells as controls. p53/p55-TRIM59 proteins possibly represent Ser/Thr and Tyr phosphorylation modifications, respectively. Quantitative measurements by ELISA showed that the p-Ser/Thr TRIM59 correlated with tumorigenesis, whereas the p-Tyr-TRIM59 protein correlated with advanced cancer of the prostate (CaP). The function of TRIM59 was elucidated using short hairpin RNA (shRNA)-mediated knockdown of the gene in human CaP cells, which caused S-phase cell-cycle arrest and cell growth retardation. A hit-and-run effect of TRIM59 shRNA knockdown was observed 24 hours posttransfection. Differential cDNA microarrray analysis was conducted, which showed that the initial and rapid knockdown occurred early in the Ras signaling pathway. To confirm the proto-oncogenic function of TRIM59 in the Ras signaling pathway, we generated a transgenic mouse model using a prostate tissue-specific gene (PSP94) to direct the upregulation of the TRIM59 gene. Restricted TRIM59 gene upregulation in the prostate revealed the full potential for inducing tumorigenesis, similar to the expression of SV40 Tag, and coincided with the upregulation of genes specific to the Ras signaling pathway and bridging genes for SV40 Tag-mediated oncogenesis. The finding of a possible novel oncogene in animal models will implicate a novel strategy for diagnosis, prognosis, and therapy for cancer.  相似文献   
92.
93.
Yavuz O  Cam M  Bukan N  Guven A  Silan F 《Acta histochemica》2003,105(3):261-266
The aim of the present study was the evaluation of possible protective effects of melatonin against beta-cell damage in streptozotocin-induced diabetes in rats. Malondialdehyde levels and glutathione peroxidase activity were measured in pancreatic homogenates. Pancreatic beta-cells were examined by immunohistochemical methods. Streptozotocin was injected intraperitoneally at a single dose of 60 mg/kg for induction of diabetes. Melatonin (200 microg/kg/day, ip) was injected for 3 days prior to administration of streptozotocin; these injections were continued until the end of the study (4 weeks). Streptozotocin induced a significant increase in malondialdehyde levels (p < 0.01) and a significant decrease in glutathione peroxidase activity (p < 0.05) in pancreatic tissue. Degeneration of islet cells and weak immunohistochemical staining of insulin was observed in diabetic rats. Treatment of diabetic rats with melatonin markedly reduced malondialdehyde production (p < 0.05) and increased glutathione peroxidase activity (p < 0.01) without affecting hyperglycemia. Increased staining of insulin and preservation of islet cells were apparent in the melatonin-treated diabetic rats. These data suggest that melatonin treatment has a therapeutic effect in diabetes by reduction of oxidative stress and preservation of pancreatic beta-cell integrity.  相似文献   
94.

Introduction

Coronary artery disease (CAD) and vascular erectile dysfunction (ED) are related to endothelial dysfunction. Elevated asymmetrical dimethylarginine (ADMA) levels and ED are common in patients with increased cardiovascular risk. Our aim was to investigate whether ADMA has a predictive role for major adverse cardiovascular events (MACE) in acute coronary syndrome (ACS). The secondary aim of this study was to investigate whether severity of ED predicts MACE in these patients.

Material and methods

Follow-up data were available for severity of ED in 71 patients with ACS. Plasma ADMA levels were determined by ELISA in 57 patients. Erectile dysfunction was assessed by the International Index of Erectile Function-6 (IIEF-6) score. Major adverse cardiovascular events (reinfarction, all-cause hospitalisation, stroke and all-cause death) was evaluated after a median of 10 months.

Results

Severe ED had no significantly increased hazard ratio for cardiovascular events compared with mild, mild to moderate, and moderate ED (0.259 [95% CI 0.041–1.6], p = 0.147; 0.605 [95% CI 0.095–3.8], p = 0.594; 0.980 [95% CI 0.233–4.1], p = 0.978; and 0.473 [95% CI 0.052–1.3], p = 0.508). The patients who had ADMA levels ≥ 0.32 µmol/l had no significantly increased hazard ratio for cardiovascular events compared with patients who had ADMA levels < 0.32 µmol/l (2.018 [95% CI 0.615–6.6], p = 0.247).

Conclusions

Severity of ED and ADMA did not increase the risk of cardiovascular events in follow-up patients with ACS in our study. Larger prospective studies are necessary to evaluate whether ADMA predicts cardiovascular events in patients with ACS.  相似文献   
95.

Background  

Computer-based teaching (CBT) is a well-known educational device, but it has never been applied systematically to the teaching of a complex, rare, genetic disease, such as Hunter disease (MPS II).  相似文献   
96.
In order to study the incidence of hepatitis C virus (HCV) infection in Tunisian haemodialysis patients and detect its nosocomial transmission, 395 patients were enrolled in a prospective study (November 2001-2003). HCV serological and virological status was determined initially using, respectively a third generation ELISA and an RT-PCR qualitative assay. The genotype of the HCV isolates was determined by sequencing NS5B region. The issue of nosocomial transmission was addressed by sequencing the HVR-1 region of the E2 gene. About 20% of the patients had anti-HCV antibodies and HCV-RNA was detected in 73% of the anti-HCV positive patients. Two cases of de novo HCV infection were identified in two dialysis centers, during virological follow-up of patients susceptible to HCV infection. The incidence of de novo HCV infection was 0.5%. Determining the genotypes in the first center disclosed that all HCV-positive patients were infected with genotype 1b; sequencing of the HVR-1 region of the E2 gene provided strong evidence that the isolate from the newly infected patient and another infected dialysis patient were closely related, confirming nosocomial contamination. The investigation of the second center is pending. Besides, one patient with negative HCV serology had detectable HCV-RNA at the beginning of the study. This case had HCV genotype 1b, two other infected dialysis patients in the same unit had HCV genotypes 4k and 3a; thus precluding nosocomial transmission. Thanks to molecular and phylogenetic methods, one case of nosocomial HCV transmission in haemodialysis was confirmed. Epidemiological investigation suggested nosocomial transmission via the medical and/or nursing staff.  相似文献   
97.
Sickle cell disease (SCD) is associated with alterations in immune phenotypes. CD4+CD28null T lymphocytes have pro-inflammatory functions and are linked to vascular diseases. To assess the percentage of CD4+CD28null T lymphocytes, natural killer cells (NK), and IFN-gamma levels, we compared 40 children and adolescents with SCD with 40 healthy controls and evaluated their relation to disease severity and response to therapy. Patients with SCD steady state were studied, focusing on history of frequent vaso-occlusive crisis, hydroxyurea therapy, and IFN-gamma levels. Analysis of CD4+CD28null T lymphocytes and NK cells was done by flow cytometry. Liver and cardiac iron overload were assessed. CD4+CD28null T lymphocytes, NK cells, and IFN-gamma levels were significantly higher in patients than controls. Patients with history of frequent vaso-occlusive crisis and those with vascular complications had higher percentage of CD4+CD28null T lymphocytes and IFN-gamma while levels were significantly lower among hydroxyurea-treated patients. CD4+CD28null T lymphocytes were positively correlated to transfusional iron input while these cells and IFN-gamma were negatively correlated to cardiac T2* and duration of hydroxyurea therapy. NK cells were correlated to HbS and indirect bilirubin. Increased expression of CD4+CD28null T lymphocytes highlights their role in immune dysfunction and pathophysiology of SCD complications.  相似文献   
98.
Regulatory T cells (Treg) has been documented to be protective against myocardial ischemia–reperfusion injury (MIRI). The administration of drugs which recruit Treg cells may participate in the cardioprotection of MIRI. The purpose of the present study was to investigate whether the add-on vildagliptin (vild) to standard treatment of MIRI prior to reperfusion could increase Treg recruitment, anti-inflammatory, and antioxidant effects of the standard treatment or not. Sixty diabetic patients with ST-segment elevation myocardial infarction were randomly divided into two equal groups: control group was given the standard medical treatment and vild group was given the standard medical treatment plus vild. There were no statistical differences between the mean of percentage of changes in nitric oxide, ischemia modified albumin, highly sensitive C reactive protein, and interferon-gamma levels in the studied groups. While, the percentages of changes of myeloperoxidase level, CD4+CD25+ Treg cells count, and transforming growth factor-beta1 level were significantly higher in vild group compared with control group. We concluded that addition of vild to standard medical treatment of MIRI could increase its effectiveness through recruitment of CD4+CD25+ Treg cells.  相似文献   
99.
Herein we report the case of a patient with primary amenorrhea and cyclic menouria. The patient was a 20-year-old woman with primary amenorrhea and inability to achieve sexual intercourse. Clinical examination revealed normally developed labia majora and minora, clitoris, and external urethral orifice, but no vaginal opening. A mature female pubic hair pattern was present, and axillary hair development was normal. Breasts were normally developed. Abdominopelvic magnetic resonance imaging demonstrated a remnant upper vagina and unicornuate uterus filled with fluid, and left-sided renal agenesis. Intraoperatively, a congenital vesicouterine fistulous tract was observed. The fistulous tract was completely resected. Vaginal reconstruction using a sigmoid colon pedicled flap was performed. The proximal part of the neovagina was connected to the remnant cervix, and a Foley catheter was left in the uterine cavity for 7 days to prevent obstruction. The patient has been menstruating regularly since the operation. Menouria might be an early sign of congenital vesicouterine fistula. Resection of the fistulous tract with uterine preservation might be considered in patients with vaginal agenesis.  相似文献   
100.
Ticks (n = 663) and fleas (n = 470) collected from domestic animals from southeastern Tunisia were screened for Rickettsia infection using reverse line blot assay. Evidence of spotted fever group Rickettsia was obtained. We detected Rickettsia felis in fleas, Rickettsia massiliae Bar 29 and the Rickettsia conorii Israeli spotted fever strain in ticks, and Rickettsia conorii subsp. conorii and Rickettsia spp. in both arthropods. The sensitivity of the adopted technique allowed the identification of a new association between fleas and R. conorii subsp. conorii species. The presence of these vector-borne Rickettsia infections should be considered when diagnosing this disease in humans in Tunisia.  相似文献   
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