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991.
OBJECTIVE: The aim of this study was to determine the rate of occult hepatitis B virus (HBV) infection among blood donors living in a geographic region of low (5.6%) anti-HBc prevalence. SUBJECTS AND METHODS: Sera from 150 candidate blood donors whose blood was rejected due to total anti-HBc reactivity (despite absence of HBsAg) were tested for anti-HBs and IgM anti-HBc antibodies, as well as for HBeAg/anti-HBe. Serum HBV DNA was sought by using a PCR assay able to amplify part of the surface gene. Viral load was measured in the PCR positive samples. RESULTS: The pattern 'anti-HBc alone' (without HBsAg and anti-HBs antibodies) was found in 64 (42.7%) subjects. IgM anti-HBc and anti-HBe antibodies were detected in 2 (1.3%) and 80 (53.3%) samples, respectively. No sample was HBeAg-reactive. HBV DNA was repeatedly found in five (3.3%) samples, three of which were anti-HBs positive and two anti-HBs negative. All five HBV DNA positive samples showed a low viral load (<1000copies/ml). CONCLUSIONS: The data indicated a low rate of occult infection among anti-HBc positive, HBsAg negative blood donors living in a region of low prevalence of infection. Viral load was very low in all HBV infected subjects.  相似文献   
992.
BACKGROUND: Liver iron deposits are frequent in viral C cirrhotic patients but their role is not well defined. AIMS: To investigate the effect of liver iron excess on the prevalence of hepatocellular carcinoma (HCC) in patients with viral C cirrhosis. METHODS: Hepatic iron was evaluated retrospectively using a semiquantitative method in liver biopsies of 104 viral C cirrhotic patients, 48 with HCC and 56 controls (HCC free). Corrected total iron score (0-60) was defined by the sum of three scores: hepatocytic iron score (0-36), sinusoidal iron score (0-12), and portal iron score (0-12), multiplied by 3/3, 2/3, or 1/3 according to the heterogeneous iron localisation in the nodules. RESULTS: After adjustment for known risk factors for HCC, regression analysis showed that iron deposits (corrected total iron score >0) were more frequent in HCC patients than in controls (odds ratio 4.94; 95% confidence interval 1.59-15. 32; p=0.0056). The median of corrected total iron score was significantly higher in HCC patients than in controls (odds ratio 1. 092; 95% confidence interval 1.01-1.13; p=0.021). This liver iron overload was sinusoidal (odds ratio 5.2; 95% confidence interval 1. 82-15.11; p=0.0022). CONCLUSIONS: Liver iron deposition was more frequent and more important in viral C cirrhotic patients with HCC than in HCC free controls. Liver iron overload seems to contribute to the development of HCC in patients with viral C cirrhosis.  相似文献   
993.
We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available.  相似文献   
994.
The frequency of Entamoeba histolytica and Entamoeba dispar infection was analyzed in a rural community in the state of Morelos, Mexico, using polymerase chain reaction (PCR). Sociodemographic variables as risk factors for the infection were assessed. Results highlighted the number of individuals with intestinal parasites (43.1%) in the community, indicating extensive fecalism. A high frequency of E. histolytica asymptomatic infection, higher than E. dispar infection (13.8% versus 9.6%), was detected by PCR. Anti-amebic antibody levels (IgG) in serum and saliva (IgA) samples were not associated with E. histolytica intestinal infection. These findings suggest a predominant distribution of E. histolytica strains of low invasive potential in this community.  相似文献   
995.
Warren  AP; Patel  K; McConkey  DJ; Palacios  R 《Blood》1996,87(9):3676-3687
In our search for cell surface markers expressed on hematopoietic stem cells and/or very early progenitor cells we found that the Joro 177 monoclonal antibody (MoAb) bound to most hematopoietic cells in day 8/8.5 yolk sac, day 12 fetal liver, and day 13 fetal thymocytes; it stained hematopoietic stem cells and less immature lymphoid, myeloid, and erythroid-lineage cells, but not most thymocytes and splenic lymphocytes in adult mice. Joro 177 MoAb stimulated tyrosine phosphorylation of an integral of 124-kD protein and induced homotypic aggregation of lymphoid progenitor cells. Importantly, Joro 177 MoAb inhibited cell survival/growth and consequently the generation of lymphoid, myeloid, and erythroid lineage cells in vitro from early Lin- hematopoietic precursors. Joro 177 MoAb induced apoptosis of hematopoietic progenitor cells. Molecular cloning and expression indicated that Joro 177 MoAb recognizes a type II transmembrane protein, which is the mouse homologue of the human CD98 heavy chain gene. We suggest that CD98 is a cell membrane receptor involved in the control of cell survival/death of hematopoietic cells.  相似文献   
996.
997.
Unilateral lung transplantation of two organs allows two patients to benefit from a single donor. We report the first and only such transplants--carried out simultaneously in the same surgical unit--to be performed in Spain to date. The diagnosis was idiopathic pulmonary fibrosis in both cases and the donor came from the same hospital. No complications developed during the subsequent hospital stay. Two years later, both patients are asymptomatic and carrying out normal activities with no limitations.  相似文献   
998.
Background. Incisional surgical site infections (ISSIs) are common bacterial infections in heart transplantation (HT). The purpose of this study was to determine the incidence, etiology, timing, and risk factors for ISSIs.
Methods. A prospective study was performed, which included all heart transplants carried out in the participating hospitals (pertaining to the Spanish National Hospital Network RESITRA) between August 2003 and February 2005. A population of 292 consecutive patients was included (84.9% males). The definition of ISSI used in the study was based on the Centers for Disease Control criteria.
Results. Seventeen episodes of ISSIs were recorded in 14 patients (4.8%; confidence interval [CI] 95% 2.7–7.7%). The median time from transplant to ISSI was 14 days (range 3–75). Two patients (14%) died; fatality was related to ISSI (mediastinitis) in 1 patient (7%). Coagulase-negative staphylococci (7 cases), methicillin-resistant Staphylococcus aureus (3 cases), Proteus mirabilis , extended-spectrum β-lactamase-producing Escherichia coli , Candida albicans , and Candida glabrata , 1 case each, were the isolated pathogens. The duration of extracorporeal circulation was longer in patients with ISSI, although the difference did not reach statistical significance. Antibiotic prophylaxis with ciprofloxacin alone (odds ratio, 15.8; 95% CI, 1.2–216.9) was independently associated with the development of ISSI.
Conclusions. ISSIs in HT are frequently caused by resistant bacteria and Candida , but are associated with good prognosis.  相似文献   
999.
1000.
OBJECTIVE: To evaluate the frequency of microalbuminuria and its relationship with several risk factors and left ventricular mass in a population of mildly hypertensive subjects attended in a primary-care setting. DESIGN: Cross-sectional study. SETTING: Eight primary-care centres. PATIENTS: Two hundred and twenty-three non-diabetic patients recently diagnosed with mild hypertension were included in the study. None of them had clinical evidence of target-organ damage or had received prior antihypertensive treatment. INTERVENTIONS: Subjects included in the study underwent clinical interview, measurement of blood pressure (BP) on three visits, blood analysis, measurement of albumin by immunonephelometry in three overnight urine collections, 24 h BP monitoring and M-mode and Doppler echocardiography. MAIN OUTCOME MEASURES: Tobacco habit, clinic BP, body mass index, serum lipids and uric acid, glycaemia, urinary albumin excretion (UAE), ambulatory BP and left ventricular mass index. RESULTS: The frequency of microalbuminuria was 7.2%. Microalbuminuric patients were more likely to be men and to be characterized by higher ambulatory BP, body mass index and uric acid levels. Regression analysis demonstrated that male sex and 24 h systolic BP were determinants of UAE. Patients with white-coat hypertension showed lower UAE than did subjects with sustained hypertension. Although a certain relationship between UAE and left ventricular mass index was found, these variables were not significantly correlated. CONCLUSIONS: A low proportion of mildly hypertensive patients attended in a primary care setting are microalbuminuric. In this population, UAE is an expression of BP values over 24 h and correlates with several risk factors.  相似文献   
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