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101.
102.
Previous work has shown that in experimental animal models a lower incidence of arrhythmias and sudden death was observed if the animals were fed cod liver oil or fish oil. After a 48-h control period starting, on average, 8 days after the onset of symptoms, 18 men who were recovering from acute myocardial infarction were given 20 ml d-1 cod liver oil for 6 weeks, either immediately after the control period, weeks 0-6 (n = 10), or during weeks 6-12 (n = 8). Forty-eight-hour Holter monitoring was carried out before cod liver oil administration and at the end of weeks 6 and 12. The eicosapentaenoic acid content of plasma phospholipids was increased by 230% during cod liver oil administration. However, no significant change was observed in the 24-h prevalence of ventricular extrasystoles or other arrhythmias during the study period. The mean ln number of ventricular extrasystoles was 2.95 +/- 0.51 (+/- SEM) during cod liver oil ingestion and 2.63 +/- 0.30 when not taking cod liver oil.  相似文献   
103.
INTRODUCTION: Clinical, neuropsychological and functional neuroimaging studies in schizophrenia suggest impaired frontal lobe function, especially of the dorsolateral prefrontal region (DLPFR). This dysfunction has in particular been associated with negative or "deficit" symptoms. Despite these findings, morphological studies have failed to show consistent structural abnormalities in the frontal lobe. This may be because existing techniques are not sensitive enough to detect structural abnormalities or that dysfunction in the frontal lobe is caused by lesions elsewhere. We used volume-localised proton magnetic resonance spectroscopy (1H-MRS) to measure N-acetylaspartate (NAA), a neuronal marker, to evaluate the neuronal integrity of the dorsolateral prefrontal region in schizophrenic patients with persistent negative symptoms and in healthy comparison subjects. METHOD: Twenty-five patients who fulfilled DSM-IV criteria for schizophrenia and met the criteria for the Deficit syndrome were compared to 26 healthy controls matched for age and gender. Bilateral proton MR spectra were collected from a 2-cm(3) volume in the dorsolateral prefrontal region and the absolute concentrations of N-acetylaspartate, choline (Cho) and creatine+phosphocreatine (Cr+PCr) were measured. RESULTS: There was a significant negative correlation between severity of symptoms and NAA concentration in the schizophrenic patients. This was more marked for positive symptoms and for general psychopathology than for negative symptoms. There was also a significant correlation between NAA concentration and social functioning within the schizophrenic group. There were no significant differences between the two groups for the three metabolites. CONCLUSIONS: The negative association between severity of symptoms and NAA in schizophrenic patients and an association of NAA with social functioning suggest that NAA may be an indicator of disease severity. The lack of significant mean difference in NAA between the two groups suggests that there is no marked neuronal loss in the dorsolateral prefrontal region in schizophrenia.  相似文献   
104.
Context  Myocardial infarction (MI) is the leading cause of death in the world. Variants in the 5-lipoxygenase–activating protein (FLAP) gene are associated with risk of MI. Objective  To determine the effect of an inhibitor of FLAP on levels of biomarkers associated with MI risk. Design, Setting, and Patients  A randomized, prospective, placebo-controlled, crossover trial of an inhibitor of FLAP (DG-031) in MI patients who carry at-risk variants in the FLAP gene or in the leukotriene A4 hydrolase gene. Of 268 patients screened, 191 were carriers of at-risk variants in FLAP (87%) or leukotriene A4 hydrolase (13%). Individuals were enrolled in April 2004 and were followed up by designated cardiologists from a university hospital in Iceland until September 2004. Interventions  Patients were first randomized to receive 250 mg/d of DG-031, 500 mg/d of DG-031, 750 mg/d of DG-031, or placebo. After a 2-week washout period, patients received DG-031 if they had received placebo first or placebo if they had received DG-031 first. Treatment periods lasted for 4 weeks. Main Outcome Measures  Changes in levels of biomarkers associated with risk of MI. Results  In response to 750 mg/d of DG-031, production of leukotriene B4 was significantly reduced by 26% (95% confidence interval [CI], 10%-39%; P = .003) and myeloperoxidase was significantly reduced by 12% (95% CI, 2%-21%; P = .02). The higher 2 doses of DG-031 produced a nonsignificant reduction in C-reactive protein (16%; 95% CI, –2% to 31%; P = .07) at 2 weeks. However, there was a more pronounced reduction (25%; 95% CI, 5%-40%; P = .02) in C-reactive protein at the end of the washout period that persisted for another 4 weeks thereafter. The FLAP inhibitor DG-031 was well tolerated and was not associated with any serious adverse events. Conclusion  In patients with specific at-risk variants of 2 genes in the leukotriene pathway, DG-031 led to significant and dose-dependent suppression of biomarkers that are associated with increased risk of MI events.   相似文献   
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106.
OBJECTS: The aim of this study was to evaluate the prognostic significance of the current WHO histological subtyping and Fuhrman nuclear grading on the survival of patients with renal cell carcinoma (RCC). MATERIALS AND METHODS: A retrospective population-based study was carried out on all patients with a histopathologically confirmed diagnosis of RCC in Iceland between 1971 and 2000. Fuhrman grade, TNM stage, and survival were evaluated and multivariate analysis applied in order to determine prognostic factors. RESULTS: Out of 629 patients (387 males, 242 females, mean age 64 years), 558 (88.7%) had clear cell, 53 (8.4%) papillary, and 13 (2.1%) chromophobe RCC. Patient demographics were comparable for the two major subtypes, but chromophobe RCCs were larger in size and were diagnosed at a younger age. Clear cell RCCs were more often of higher grades (G3+G4, 48.4%) and at advanced TNM stages (III+IV, 59.3%) than papillary RCCs (22.6% and 34% respectively, p<0.001). Linear regression analysis showed a strong correlation between grade, tumor size, and stage (p<0.001). Chromophobe RCCs had a better survival in univariate analysis than both papillary and clear cell RCCs (84.6% vs. 66.5% and 54.9% 5-year disease specific survival, p<0.001). However, in the multivariate analysis, only the patient's age, calendar year of diagnosis, TNM stage, and nuclear grade were independent prognostic factors of survival. CONCLUSION: In this complete nation-wide series nuclear grading is important in predicting survival of patients with RCC. It is strongly related to both tumor size and stage, with stage being by far the strongest prognostic factor. Different histological subtypes confer different survival. However, in spite of the distinctive cytogenetic and molecular characteristics of the subtypes, the survival difference is to a large extent due to differences in grade and particularly stage.  相似文献   
107.
PURPOSE: To establish risk factors for five-year incidence of age-related macular degeneration (AMD). DESIGN: Population-based, prospective cohort study, and risk analysis. METHODS: A random sample from the Reykjavik Population Census for individuals 50 years and older was selected. We took fundus stereo color photographs and used standard grading system to study the five-year incidence of drusen, pigmentary abnormalities, and AMD and to examine possible risk factors. A questionnaire including information on disease, medication, diet, and lifestyle from the Reykjavik Eye Study database provided additional information. RESULTS: Current alcohol consumption decreased the risk for drusen. Being married rather than divorced or widowed decreased the risk for soft drusen; being single decreased the risk of hypopigmentation as compared with being divorced or married. Both consuming dietary fiber-rich vegetables and meat and meat products once a week or less frequently was a risk factor for developing soft drusen and decreased the risk of pigmentary abnormalities. Those who had smoked 20 pack-years or more as compared with nonsmokers had decreased survival rate over the five years (odds ratio (OR) 0.46, 95% confidence interval (CI) 0.27 to 0.80; P = .006). CONCLUSIONS: Risk factors for drusen appear to differ from risk factors for pigmentary abnormalities. The effect of smoking on developing AMD is partly masked by selective mortality.  相似文献   
108.
Avoidance of multiple pregnancy by use of single embryo transfer   总被引:3,自引:0,他引:3  
The benefits of single embryo transfer (SET) for both mother and child are evident. Already twin pregnancies constitute a relatively serious problem exemplified by the incidence of cerebral palsy, which will increase significantly as well as a risk for premature birth. Selective embryo reduction in countries where this is allowed may be one way to acutely solve the situation. In the beginning the use of natural cycle in vitro fertilization (IVF) avoided the problem, but with the introduction of controlled ovarian hyperstimulation predominantly by use of gonadotrophins in the early 1980ies the temptation to replace more than 1 embryo at a time became too strong. SET with maintenance of acceptable pregnancy rates can only be achieved if tools (improved morphological criteria, biomarkers, preimplantation genetic screening) to select the most viable/normal embryos are at hand together with improved cryopreservation procedures. In reports from Finland and Belgium already 5 years ago, elective single embryo transfer (eSET) was shown to reach almost the same success rates as double embryo transfer (DET) in selective patient groups (age under 37, good quality embryos). The indications for eSET have increased during the last years. In Finland the initiative came from the IVF clinics while in Sweden a legislative process (in act from January 2003) resulted in the recommendation that eSET should be used in the vast majority of the IVF cycles. In both these Nordic countries around 60% of the transfers are today eSET and the multiple pregnancy rate below 10% with no triplets. From an economical point of view, it is of course evident that multiple pregnancies with the numerous potential complications should be avoided altogether. Countries where IVF is included in the government health insurance will thus most likely show the way towards an even more successful, safer and cheaper treatment of infertile couples in the future.  相似文献   
109.
Myxoid variant of follicular dendritic cell sarcoma arising in the breast   总被引:5,自引:0,他引:5  
Follicular dendritic cell sarcoma is a malignant tumor of the follicular dendritic cell which can arise in extranodal sites. We present here a case arising as a mass in the breast of a 41-year-old woman. The tumor was composed of mildly pleomorphic spindly cells with pale ovoid nuclei and cell processes intimately admixed with mature lymphocytes. In much of the lesion the cells were dispersed in cords in a myxoid stroma, and elsewhere there were solid sheets. The neoplastic cells were immunoreactive for CD21, CD35, EMA, and S100 protein, but not for other lymphoid markers or cytokeratin. Electron microscopy showed interdigitating cytoplasmic processes with junctions but no external lamina. The differential diagnosis includes carcinoma, lymphomas, and a variety of myxoid sarcomas. The tumor recurred within a few months and displayed increased nuclear pleomorphism and lymphatic invasion but the patient appears free of disease 3 years after the further excision. This case extends the spectrum of follicular dendritic cell sarcoma in soft tissue sites.  相似文献   
110.
An association between Kaposi's sarcoma (KS) and malignant lymphoma has been suspected for many years. Both cancers belong to the group of malignancies associated with immune suppression and have been known to occur in the same individual. Accordingly, a common etiology has been suspected. Through linkage within the Nordic cancer registries, we studied the occurrence of cancers in a population-based cohort of 741 patients with classical KS. The relative risk of subsequent malignancies was expressed as the ratio of the observed numbers of cancer to the numbers expected based on age-, sex-, period- and country-specific incidence rates, i.e., the standardized incidence ratio (SIR). A total of 104 cancers was observed during 5,802 person-years of follow-up, which was close to the expected 98.8 cases (SIR, 1.05). During the first year of follow-up, 3 lymphomas were observed, which is in significant excess of the 0.2 lymphomas expected (SIR, 13.0). In contrast, no lymphomas occurred in the period beyond the first year of follow-up vs. 2.3 expected. Cancers of the buccal cavity and pharynx (SIR, 10.6; n = 4) and of the colon (SIR, 2.7; n = 7) occurred in excess among women but not among men. Accordingly, our results indicate that patients with classical KS are not at increased risk of cancer in general. In particular, the overall risk of lymphomas was not significantly increased. The high relative risk of malignant lymphoma immediately after KS was based on a limited number of cases, and this observation is unlikely to indicate a common etiology. Int. J. Cancer 73:840–843, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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