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51.

Background

Disc space narrowing, osteophytes, and disc degeneration are common and increase with aging. Few animal models are appropriate for the study of spontaneous age-related cervical disc degeneration.

Questions/purposes

We used the sand rat, a member of the gerbil family with well-recognized age-related lumbar disc degeneration, to determine whether spontaneous cervical disc degeneration differed from lumbar degeneration when evaluated by (1) radiologic and (2) histologic measures. Animals 2 to 25 months of age were used in these analyses.

Methods

Cervical and lumbar discs of 99 sand rats were analyzed with radiology, and cervical discs of 67 sand rats were studied with histology. Lateral digital radiographs of cervical and lumbar spines were scored for presence or absence of wedging, disc space narrowing, osteophytes, end plate calcification, and irregular disc margins at C2-C3 through C6-C7 and T12-L1 through L7-S1. Percentages for presence were calculated and statistically analyzed for younger (range, 2-11.9 months old) versus older (range, 12.0-25 months old) animals.

Results

Cervical discs in younger animals exhibited a greater proportion of irregular margins compared with lumbar sites (94% versus 83%; p = 0.02; 95% CI for difference, 2.7, 19.0%). In older animals, cervical discs showed a greater proportion of osteophytes than did lumbar discs (7% versus 0%; p < 0.0001). The incidence of disc space narrowing was greater in cervical versus lumbar sites (99% versus 90%; p = 0.0008). Cervical spine sites which contained osteophytes morphologically showed irregular disc margins and revealed an extrusion of herniated disc material in the osteophytes.

Conclusions

Radiologic and morphologic studies confirmed age-related disc degeneration in the cervical spine of the sand rat.

Clinical Relevance

Clinical cervical aging studies have shown that 14% of asymptomatic subjects younger than 40 years have abnormal MRI scans with an increase to 50% by 50 years old. We studied an economic rodent model for cervical age-related spontaneous disc.  相似文献   
52.
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
53.
54.
目的 观察颈中交感神经节阻滞治疗脑梗塞的临床效果。方法 将 6 4例脑梗塞患者按就诊次序随机分为两组 :(1)颈中交感神经阻滞组 (下简称阻滞组 ) :34例。 (2 )对照组 :30例。两组在脑梗塞常规用药上相同 ,阻滞组采用气管旁颈 6横突法 ,隔日阻滞 1次 ,共 6次。 2周后进行疗效评定。结果 阻滞组总有效率 (88 2 3 % )明显高于对照组 (6 0 % )。结论 颈中交感神经节阻滞是一种创伤较小的侵入性交感神经阻断技术 ,对缺血性脑血管病疗效确切  相似文献   
55.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
  相似文献   
56.
57.
In 22 patients with malignancies, treated with high-dose chemoradiotherapy and autologous bone marrow transplantation (BMT), peripheral blood T cell subsets and functions were studied. In ten cytomegalovirus (CMV)-negative patients, CD4+ and CD8+ T cells (representing T cells of the helper/inducer phenotype and T cells of the suppressor/cytotoxic phenotype, respectively), recovered slowly and simultaneously. In 12 CMV-positive patients, however, CD8+ T cells recovered more rapidly than CD4+ T cells and rose to increased counts. No T cells with an immature phenotype (CD1+, OKT6+) were observed. Lymphocyte stimulation by herpes simplex virus infected fibroblasts (and by CMV-infected fibroblasts in CMV-positive patients) in contrast remained high and even increased after BMT in both groups. These data indicate that T cell recovery after autologous BMT is mainly due to proliferation of mature T cells present in the BM graft and not to generation of new T cells from T cell precursors.  相似文献   
58.
Atrial septal aneurysms have been related (either by association or as potential causes) to systolic clicks, atrial arrhythmias, systemic and pulmonary embolism, atrioventricular valve prolapse and atrial septal defect. To study these associations and the incidence of atrial septal aneurysm, we reviewed 80 consecutive patients (female to male ratio 1.9:1, mean age 47 years, range 1 day to 89 years) who had been identified prospectively as having an atrial septal aneurysm. These were found in 36,200 two-dimensional echocardiographic studies (incidence: 0.22% overall; 0.29% in the last year of the study done between 1978 and 1984). Three types of fossa ovalis aneurysm and one type of aneurysm involving the entire atrial septum were observed; a fossa ovalis aneurysm with leftward projection and excursion of less than 5 mm or an aneurysm involving the entire atrial septum with rightward projection was not observed. Atrial septal aneurysm occurred more often as an isolated abnormality than in association with other cardiac malformations, although all patients with an aneurysm involving the entire atrial septum had complex congenital cardiac anomalies of the hypoplastic right heart type. The reported associations between atrial septal aneurysms and atrial septal defect, atrioventricular valve prolapse, midsystolic clicks, atrial arrhythmias and cerebral ischemic events were examined. A hypothesis based on interatrial pressure gradients is proposed to explain the different motions and configurational characteristics of fossa ovalis aneurysms observed in these patients. All patients in whom atrial septal aneurysm is demonstrated should undergo examination for atrial septal defect. Atrial septal aneurysm should be specifically looked for in patients who have these associations and who undergo two-dimensional echocardiography, especially if these abnormalities are unexplained.  相似文献   
59.
When steady state pressure-flow relations are studied in the circumflex coronary artery, pressure gradients develop between it and other branches of the left coronary artery. To assess the effects of these pressure gradients, we compared the pressure axis intercept and shape of steady state circumflex pressure-flow relations in the presence and absence of gradients after autoregulation was abolished, both in the beating heart and during long diastoles in dogs. We used peripheral coronary pressures and radionuclide-labeled microspheres to assess arterial collateral flow. In the beating heart, interarterial pressure gradients reduced the curvature at low circumflex pressures, and overestimated the mean pressure axis intercept by 7.8 mm Hg (P less than 0.05). The results were similar for the pressure-flow relations derived during long diastoles. This overestimation exaggerates the difference between the pressure axis intercept and coronary sinus pressure. The peripheral coronary pressure and microsphere results indicate that these effects are mediated largely by arterial collateral flow.  相似文献   
60.
Background contextCarragee et al. have recently shown that modern discography injections are associated with subsequent acceleration of disc degeneration, herniation, and loss of disc height. Although needle puncture and pressurization are known trauma events that can create disc degeneration in animal models, another likely culprit in clinical discography–associated degeneration is a direct effect of the contrast agent itself on disc cells.PurposeTo test the hypothesis that discography contrast solution would have a deleterious effect on human annulus cells in vitro.Study designAn in vitro study using cultured human annulus cells to assay cell death, cell proliferation, and apoptosis.Patient sampleAnnulus cells from eight surgical disc specimens were evaluated (two Thompson Grade III discs and six Grade IV discs) for cell death and proliferation, and an additional five cultures were tested for apoptosis.Outcome measuresThe proportion of dead and live cells, cell proliferation, and the proportion of apoptotic cells in control and experimental groups.MethodsAfter internal review board approval, experimental design used two sets of controls: untreated cells under our normal culture conditions (control) and a set with added glucose to adjust the osmolality to match respective Isovue radiocontrast solution treatments (glucose controls) using a freezing point osmometer. Treated cells received Isovue 200 (iopamidol, Isovue-M 200; Bracco Diagnostics, Inc., Princeton, NJ, USA) at 12.5, 25, 50, or 100 mg/mL. Twenty thousand cells/well were seeded in triplicate in 24 well plates, control or test media added, and incubated for 24 hours. At termination, dead cells were identified with trypan blue staining and percentage dead cells determined. Cells were also tested to determine the percentage of apoptotic cells after 50 or 100 mg/mL Isovue exposures. Proliferation assays used standard plate reader methods. Statistical analysis used repeated measures analysis of variance with SAS software (version 9.2; SAS Institute, Inc., Cary, NC, USA).ResultsAnalysis of cell death showed a significant increase in the percentage of dead cells with increasing Isovue concentrations compared with control cells (p=.018–.0008). Cell proliferation analyses showed significantly reduced division in Isovue-treated cells (p=.004), and apoptosis assays revealed a significantly higher proportion of apoptotic cells in cells exposed to 50 and 100 mg/mL Isovue (p=.016 and .0003, respectively).ConclusionsDiscography is used extensively in the evaluation of low back pain. Because the lifetime prevalence of disc degeneration and low back pain is high (80% in the general population), many patients may undergo this procedure. Data presented here show that cells exposed in vitro to a radiocontrast agent with adjustments for osmolality have significantly reduced proliferation, increased cell death, and increased programmed cell death (apoptosis). In light of the well-recognized age- and degeneration-related decrease in disc cell numbers, it is possible that radiocontrast exposure may be contributing significantly to disc cell loss with subsequent progression of disc degeneration. Findings presented here provide a plausible cell-based explanation for the previously reported disc degeneration in patients receiving discography contrast solutions.  相似文献   
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