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Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.  相似文献   
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In addition to the reproductive consequences, polycystic ovary syndrome (PCOS) is characterized by a metabolic disorder in which hyperinsulinemia and insulin resistance are central features. The effects and possible benefits from insulin-sensitizing drugs are not well known, especially in non-obese women with PCOS. This study was designed to evaluate the effects of metformin and flutamide on metabolic parameters and insulin resistance in non-obese women with PCOS. Thirty non-obese women newly diagnosed with PCOS and 15 age- and weight-matched healthy volunteers as controls were included in the study. Patients were assigned randomly to receive flutamide 250 mg daily or metformin 850 mg three times daily. Glucose, insulin, insulin resistance, androgen levels and glucose and insulin responses to an oral glucose tolerance tests (OGTT) were assessed before and after a 4-week therapy period. A positive correlation was found between body mass index and insulin level in patients with PCOS and controls. Follicle stimulating hormone, luteinizing hormone, free testosterone and dehydroepiandrosterone sulfate levels decreased significantly, but insulin resistance levels were not changed after flutamide therapy. Body weight, free testosterone, insulin and insulin resistance levels decreased significantly after metformin therapy. In conclusion, metformin treatment improved insulin sensitivity and decreased androgen levels, and flutamide decreased androgen levels but failed to improve insulin sensitivity in the non-obese women with PCOS.  相似文献   
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PURPOSE: The toxicity of allogeneic stem-cell transplantation can be substantially reduced using a reduced-intensity conditioning (RIC) regimen. This has increased the proportion of patients with myeloid malignancies eligible for allogeneic transplantation. However, the capacity of RIC allografts to produce durable remissions in patients with acute myeloid leukemia (AML) and myelodysplasia (MDS) has not yet been defined, and consequently, the role of RIC allografts in the management of these diseases remains conjectural. PATIENTS AND METHODS: Seventy-six patients with high-risk AML or MDS received an allograft using a fludarabine/melphalan RIC regimen incorporating alemtuzumab. The median age of the cohort was 52 years (range, 18 to 71 years). RESULTS: The 100-day transplantation-related mortality rate was 9%, and no patient developed greater than grade 2 graft-versus-host disease. With a median follow-up of 36 months (range, 13 to 70 months), 27 patients were alive and in remission, with 3-year actuarial overall survival (OS) and disease-free survival (DFS) rates of 41% and 37%, respectively. The 3-year OS and DFS rates of patients with AML in complete remission at the time of transplantation were 48% and 42%, respectively. Disease relapse was the most common cause of treatment failure and occurred at a median time of 6 months after transplantation. All but one patient destined to relapse did so within 24 months of transplantation. CONCLUSION: The extended follow-up in this series identifies a high risk of early disease relapse but provides evidence that RIC allografts can produce sustained DFS in a significant number of patients with AML who would be ineligible for allogeneic transplantation with myeloablative conditioning.  相似文献   
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Background: Many studies have shown that autonomic activation is one of the major factors in the etiology of hypertension. Furthermore, sympathovagal imbalance may be responsible for arrhythmias and sudden cardiac death. The aim of the present study was to compare and to evaluate the effects of short-term therapy with amlodipine and verapamil on heart rate variability (HRV) in patients with essential hypertension. Methods: Forty patients with essential hypertension (11 men and 29 women, mean age 50.5+/-10.4 years) were included in the study. Patients with cardiac, metabolic, or any other systemic disease were excluded. Patients were randomized to receive either amlodipine (10 mg; n=20) or verapamil (240 mg; n=20). Patients underwent 24-h Holter monitoring assessment before treatment and after the 4-week treatment period. Standard deviation of normal RR intervals (SDNN), standard deviation of all 5-min mean normal RR intervals (SDANN), square root of the mean of the sum of the squares of differences between adjacent RR intervals (r-MSSD), and pNN50 (time domain variables) and TF, high-frequency power (HF), low-frequency power (LF), and sympathovagal balance (LF/HF; frequency domain variables) were analyzed before and after treatment. Results: Blood pressure (BP) was reduced to a similar degree, from 182/104 to 128/85 mmHg with verapamil and from 174/100 to 124/86 mmHg with amlodipine (verapamil p<0.001; amlodipine p<0.001). This study revealed that amlodipine had no significant effect on any of the time or frequency domain parameters. In contrast, in patients on verapamil, there were significant increases in all time domain parameters, and the LF/HF ratio was significantly decreased (p<0.05). Conclusions: These results suggest that verapamil may have additional positive effects on sympathico-parasympathetic control beyond lowering blood pressure compared with amlodipine, even after short-term treatment in hypertensive patients.  相似文献   
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