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OBJECTIVES: We sought to determine the prevalence of treatable left ventricular (LV) systolic dysfunction (LVSD) in patients who present with their first noncardiac vascular episode. BACKGROUND: Screening for LV dysfunction in patients who present with their first stroke (cerebrovascular accident), their first transient ischemic attack (TIA) or their first manifestation of peripheral vascular disease (PVD) may represent a golden opportunity to identify treatable LV dysfunction, and so their known high incidence of sudden cardiac death may be reduced. METHODS: Participating in this study were 522 (75%) of 700 consecutive patients (302 patients with stroke, TIA or PVD and 220 age- and gender-matched control subjects). Each underwent a full clinical assessment, 12-lead electrocardiography and two-dimensional echocardiography. Left ventricular dysfunction was defined as LV ejection fraction < or = 40%. RESULTS: Seventy-two (28%) patients with vascular disease and 11 (5.5%) control subjects were found to have LVSD. Twenty-six (28%) stroke patients, 22 (26%) patients with TIA and 24 (31%) patients with PVD had LVSD. Left ventricular systolic dysfunction was symptomatic in 44% of patients and in 35% of control subjects. CONCLUSIONS: Left ventricular systolic dysfunction is five times more common among patients with stroke, TIA and PVD than among age- and gender-matched control subjects. Asymptomatic LVSD is more common than symptomatic LVSD in these patients. These findings suggest that routine screening of all patients with noncardiac vascular episodes for LVSD should now be considered. Future studies should investigate whether identifying and treating LVSD in these patients would reduce their known high rate of cardiac death.  相似文献   
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Summary. Plasma fibrinogen was measured in 4837 women aged 25-64 years as part of the Scottish Heart Health Study and Scottish MONICA population surveys. The relationships of oral contraceptive use, the menopause and hormone replacement therapy were examined.
Univariate analyses found that women with a history of oral contraceptive use, premenopausal women and those on hormone replacement therapy all had significantly lower fibrinogen levels than women who had never used oral contraceptives, postmenopausal women and non-hormone replacement users respectively. These differences persisted after age standardization.
On multivariate analysis, menopausal status and hormone replacement therapy had independent effects on fibrinogen levels. Together with the common risk factors, 9.9% of the total variation in plasma fibrinogen levels was explained. However, less than 1% of this was from the combined menopausal and hormonal factors.
These results confirm a postmenopausal rise in fibrinogen level which may be relevant to an increased risk of coronary heart disease. In addition, a protective effect with hormone replacement therapy is noted, although this was probably due to selection bias.  相似文献   
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Arrhythmogenic right ventricular cardiomyopathy/dysplasia: An update   总被引:1,自引:0,他引:1  
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a genetic cardiomyopathy characterized by ventricular arrhythmias and structural abnormalities of the right ventricle (RV). The diagnosis is based on the International Task Force criteria. Cardiologists may not be aware of these diagnostic criteria for ARVC/D and may place too much importance on the results of MRI imaging of the right ventricle. Patients with ARVC/D usually have an abnormal 12-lead electrocardiogram, abnormal echocardiogram, and ventricular arrhythmias with a left bundle branch block morphology. If noninvasive testing suggests ARVC/D, invasive testing with an RV angiogram, RV biopsy, and electrophysiologic study is recommended. Once a diagnosis of ARVC/D is established, the main treatment decision involves whether to implant an implantable cardioverter-defibrillator. We also recommend treatment with β blockers. Patients with ARVC/D are encouraged to avoid competitive athletics. Recent advances in the understanding of the genetic basis of ARVC/D have revealed that ARVC/D is a disease of desmosomal dysfunction.  相似文献   
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Most acute promyelocytic leukaemia (APL) patients suffer from disordered haemostasis. APL can be treated successfully in most instances by all-trans retinoic acid (ATRA) therapy, which induces endpoint maturation of the leukaemic promyelocytes with the characteristic t(15;17). Annexin II (AnII), a profibrinolytic protein, has been implicated in the bleeding manifestation seen in APL. Our group has shown previously that high levels of AnII are expressed on other acute myeloid leukaemia subtypes that are sometimes associated with disordered haemostasis, albeit less frequently than APL. This study examined the effects of ATRA on AnII expression and cell differentiation, on myeloid leukaemia cell lines to determine whether a regulatory influence on AnII may contribute to the return of haemostatic stability in APL following treatment. The results confirmed that AnII expression in the APL cell line (NB4) was significantly downregulated in response to ATRA (P < 0.01), with associated morphological and immunophenotypical evidence of myeloid differentiation. ATRA also downregulated AnII expression on other myeloid cell lines, albeit to a lesser extent than observed on NB4 cells. The results provide evidence that ATRA may resolve the hyperfibrinolysis in APL by downregulation of AnII expression.  相似文献   
127.
A 62-year-old man with Class III heart failure and left bundle branch block underwent cardiac resynchronization therapy. Because prior implantation attempts from the left side were unsuccessful, the right side approach was attempted. However, it was still impossible to advance the pre-shaped sheaths into the distal coronary sinus (CS) because the CS was abnormal with a posterior vertical take off followed by a sharp sigmoid curve before the AV groove. Ultimately, a straight sheath was adjusted to fit the sigmoid curve with the guidance of an electrophysiologic catheter and a left ventricular lead was then passed into the anterolateral vein. There was no financial support for this study.  相似文献   
128.
Significant concern exists over the long-term results of right ventricular outflow tract repair using heterograft valved conduits. Because these conduits and valves are difficult to image using ultrasound, a serially applicable two dimensional Doppler echocardiographic, M mode echocardiographic and phonocardiographic method for noninvasive investigation was developed and applied in 15 children. The method provides two dimensional echocardiographic imaging of valve contour and motion, as well as M mode and phonocardiographic analysis and quantitative range-gated Doppler information about the timing of flow through the conduit. Conduit diameter in two dimensional echocardiographic images correlated well with known conduit size (r = +0.96). A thickened and stenosed heterograft valve was predicted in two patients before hemodynamic investigation. This new method provides serially obtainable information to aid in the management of children and infants with a valved conduit placed for repair of congenital heart malformations and aids in planning the timing of hemodynamic follow-up studies.  相似文献   
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Neuroblastoma, the most common extracranial solid tumor of childhood, is responsible for over 15 % of pediatric cancer deaths. We have shown that neuroblastoma cell lines overexpress focal adhesion kinase (FAK), a non-receptor protein tyrosine kinase that controls a number of tumorigenic pathways. In this study, we hypothesized that inhibition of FAK would result in decreased cellular migration and invasion in neuroblastoma cell lines, and decrease metastasis in a murine model. We utilized non-isogenic and isogenic MYCN human neuroblastoma cell lines and parallel methods of FAK inhibition. Cell viability, migration, and invasion assays were employed to assess the effects of FAK inhibition in vitro. A nude mouse model was utilized to determine the effects of FAK inhibition on in vivo liver metastasis. FAK knockdown with siRNA resulted in decreased invasion and migration in neuroblastoma cell lines, and the effects of siRNA-induced FAK inhibition were more pronounced in MYCN amplified cell lines. In addition, abrogation of FAK with a small molecule inhibitors resulted in decreased cell survival, migration and invasion in neuroblastoma cell lines, again most pronounced in cell lines with MYCN amplification. Finally, small molecule FAK inhibition in a nude mouse model resulted in a significant decrease in metastatic tumor burden in SK-N-BE(2) injected animals. We believe that FAK plays an important role in maintaining and propagating the metastatic phenotype of neuroblastoma cells, and this driver role is exaggerated in cell lines that overexpress MYCN. FAK inhibition warrants further investigation as a potential therapeutic target in the treatment of aggressive neuroblastoma.  相似文献   
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