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991.
OBJECTIVE: This study assesses knowledge of oral cancer risk factors, clinical signs, and oral cancer examination experience among North Carolina adults. METHODS: A statewide random digit dial, computer-assisted telephone interview was conducted in 2002. Data from 1,096 respondents, with a response rate of 62 percent, were poststratified to 2000 census data by sex, race, and age group to produce population-based estimates. Knowledge of one sign of oral cancer, four or more risk factors for oral cancer, and having ever had an oral cancer examination were compared in logistic regression models using normalized weights. RESULTS: Fourteen (95% confidence interval [CI] +/-2) percent of adults had never heard of oral or mouth cancer. Risk factor knowledge was high for 56 percent (95% CI+/-3) and associated in a logistic regression model with younger age, feeling personal factors cause cancer, and nonuse of snuff. One sign of oral cancer (sore/lesion, red or white patch in mouth, and bleeding in the mouth) was correctly identified by 53 percent (95% CI+/-3) with significantly more correct responses from younger people, nonsmokers, and some college education. Only 29 percent (95% CI+/-3) reported ever having had an oral cancer examination when this procedure was described. Most respondents reported exams performed by dentists. In a weighted logistic regression model, older age, being dentate, nonsmokers, alcohol users, and those with some college education were significantly more likely to report having ever had an oral cancer examination. CONCLUSIONS: Although there is moderate knowledge of signs and risk factors for oral cancer among North Carolina adults, knowledge deficits remain. Oral cancer examinations need to be increased, particularly among tobacco smokers.  相似文献   
992.
993.
The aim of this study was to investigate whether the mean around which arterial oxygen fluctuations take place was important in a unique animal model of oxygen-induced retinopathy. Retinopathy of prematurity (ROP) is associated with fluctuating arterial oxygen. A recent retrospective study suggested that management of high-risk preterm infants at lower oxygen saturations was associated with less severe ROP. Rat pups were raised in a variable oxygen environment around a high (24%), normal (21%) or low (17%) mean inspired oxygen for 14 d. Rat pups raised in the high (24%) mean variable oxygen environment had more retarded retinal vascular development than did rats raised in an environment that fluctuated around 21% mean oxygen. In contrast, rats raised in a lower mean (17%) but still variable oxygen environment had no discernible retinal differences from controls raised in constant room air. Rats raised in a relatively hypoxic but variable oxygen environment develop less severe retinal vascular abnormalities than those raised in variable oxygen around higher oxygen means.  相似文献   
994.
995.
996.
Our aim was to determine whether the chest radiograph appearance at 7 days predicted chronic lung disease development (oxygen dependency at 36 weeks post-menstrual age) or death before discharge and if it was a better predictor than readily available clinical data. Two consecutive studies were performed. In both, chest radiographs taken at 7 days for clinical purposes were assessed using a scoring system for the presence of fibrosis/interstitial shadows, cystic elements and hyperinflation and data were collected regarding gestational age, birth weight, use of antenatal steroids and post-natal surfactant and requirement for ventilation at 7 days. Oxygenation indices were calculated in the first study (study A) at 120 h and in the second (study B) at 168 h. In study A, there were 59 infants with a median gestational age of 26 weeks (range 24 to 28 weeks) and in study B, 40 infants with a median gestational age of 27 weeks (range 25–31 weeks). In both studies, infants who developed chronic lung disease had a significantly higher total chest radiograph score, with a higher score for fibrosis/interstitial shadowing than the rest of the cohort. Infants who died before discharge differed significantly from the rest with regard to significantly higher scores for cysts. In both studies, the areas under the receiver operator characteristic curves with regard to prediction of chronic lung disease were higher for the total chest radiograph score compared to those for readily available clinical data. Conclusion:in infants who require a chest radiograph for clinical purposes at 7 days, the chest radiograph appearance can facilitate prediction of outcome of infants born very prematurely.Abbreviations CLD chronic lung disease - CXR chest radiograph - CMV conventional mechanical ventilation - HFO high frequency oscillation - KCH Kings College Hospital - OI oxygenation index - PIE pulmonary intestinal emphysema - PMA post-menstrual age - ROC receiver operator characteristic curves - UKOS United Kingdom Oscillation Study  相似文献   
997.
BACKGROUND: Children attending day-care centers (DCCs) are at risk for Haemophilus influenzae nasopharyngeal colonization and acute otitis media. The degree to which a given strain circulates within a day-care center and the heterogeneity of strains among DCCs in a geographic area are not well-characterized. This study describes the prevalence rates of H. influenzae colonization in a large number of children attending day-care centers and examines the genetic diversity of colonizing strains and the degree of sharing among children. METHODS: Throat cultures were collected from 198 healthy children <3 years old attending 16 day-care centers in Michigan. All H. influenzae isolates were genetically typed by enterobacterial repetitive intergenic consensus PCR as the initial screening technique to identify unique strains within each child. Pulsed field gel electrophoresis was used subsequently to examine the genetic diversity of strains between children. RESULTS: There were 127 (64%) children colonized with H. influenzae. Wide variation in rates of colonization was identified among day-care centers (0 to 95%). A total of 179 genetically unique H. influenzae strains were isolated, and 47 children (37%) were colonized with 2 or more genetically distinct H. influenzae organisms. Evidence of sharing of the same strain in different children was found in 13 of 15 colonized DCCs and 23% of genotypically unique strains were shared. CONCLUSION: The degree of sharing of H. influenzae among children in this study suggests transmission of these potentially pathogenic microorganisms in day-care centers.  相似文献   
998.
OBJECTIVE: The purpose of this study was to determine whether standard therapeutic doses of dalteparin maintain peak therapeutic levels of anticoagulation during pregnancy. STUDY DESIGN: This was a prospective trial in which 13 pregnancies that required therapeutic anticoagulation were treated with dalteparin 100 U/kg every 12 hours; peak and trough (predose) low molecular weight heparin (anti-Xa activity) levels were monitored every 2 weeks. Dosage adjustments were made to maintain peak anti-Xa activity between 0.5 and 1.0 IU/ml. Bone density and bone turnover markers were measured. RESULTS: A total of 250 peak and trough low-molecular-weight heparin (LMWH) levels were obtained. Eighty-five percent of pregnancies (11/13) required an upward dosage adjustment. Trough levels were in the therapeutic range only 9% of the time, despite the maintenance of therapeutic peak levels. Bone resorption markers and density were unchanged in singleton pregnancies. CONCLUSION: Dalteparin dosing, based on weight alone, every 12 hours is inadequate to maintain most pregnant women in the therapeutic range throughout pregnancy as measured by anti-Xa activity. Trough levels are rarely in the therapeutic range, despite maintenance of therapeutic peak levels. These notable changes in low molecular weight heparin peak may explain reported failures in pregnancy.  相似文献   
999.
OBJECTIVE: Panniculectomy has been used to facilitate pelvic surgery in obese women. The goal of this study was to determine the effect of panniculectomy on staging adequacy and lymph node yield in obese women with endometrial carcinoma undergoing staging laparotomy. METHODS: A retrospective review of patients with endometrial neoplasms who underwent panniculectomy at the time of hysterectomy was performed. For each subject, two control patients were matched by body mass index (BMI). RESULTS: Twenty-seven endometrial cancer patients who underwent panniculectomy at the time of staging were identified. Panniculectomy was successfully performed in all 27 patients. While the mean number of pelvic nodes was statistically similar between the two groups (16.2 vs. 13.7) (P = 0.199), the paraaortic node count was higher in patients who underwent panniculectomy (4.3 vs. 2.9) (P = 0.032). A paraaortic node dissection was not feasible in 3 (11.1%) of the panniculectomy patients and in 11 (20.4%) of the controls (P = 0.365). There were no differences in intraoperative or postoperative complications or in survival between the two groups. CONCLUSION: Among obese women with endometrial cancer, panniculectomy is well tolerated, feasible, and associated with acceptable morbidity. While the clinical significance of an increased paraaortic node count is uncertain, our findings suggest that panniculectomy may enhance operative exposure and facilitate endometrial cancer staging.  相似文献   
1000.
OBJECTIVE: To compare stages IB1 and IB2 cervical cancers treated with radical hysterectomy (RH) and to define predictors of nodal status and recurrence. METHODS: Patients with stage IB cervical cancers undergoing RH between 1990 and 2000 were evaluated and clinicopathological variables were abstracted. The perioperative complication rate, estimated blood loss (EBL), and OR time were also tabulated. Variables were analyzed using X(2) and t tests. Disease-free survival (DFS) was calculated by Kaplan-Meier method. Multivariate analysis was performed via stepwise logistic regression. Cox-proportional hazards were used to identify independent predictors of recurrence. RESULTS: RH was performed on 109 stage IB1 and 86 stage IB2 patients. Mean age, EBL, and perioperative complication rates were similar. Overall, 38 patients (14 IB1 vs. 24 IB2) had positive nodes (P = 0.01) including 9 patients with positive para-aortic nodes (2 IB1 and 7 IB2). Parametrial involvement (PI) and outer 2/3 depth of invasion (DOI) were significantly more common in the IB2 tumors as well. Patients with IB2 disease received adjuvant radiation more frequently than IB1 patients (52% vs. 37%, P = 0.04). Univariate predictors of nodal status included lymphovascular space involvement (LVSI) (P = 0.001), DOI (P = 0.011), PI (P = 0.001), and stage (P = 0.011). Multivariate analysis identified only LVSI (OR 6.4, CI 2.4-17, P = 0. 0002) and PI (OR 8, CI 3.1-20, P = 0. 0001) as independent predictors of positive nodes. With a median follow-up of 35 months, estimates of DFS revealed tumor size (P = 0.008), nodal status (P = 0.0004), LVSI (P = 0.002), PI (P = 0.004), and DOI (P = 0.0004) as significant univariate predictors. Neoadjuvant chemotherapy, age, grade, histology, and adjuvant radiation were not associated with recurrence. The significant independent predictors of DFS were LVSI (ROR 5.7, CI 2-16, P = 0.0064) and outer 2/3 DOI (OR 5.8, CI 2-20, P = 0.0029). Neither tumor size nor nodal status was a significant predictor of DFS. CONCLUSIONS: The prognosis in stage IB cervical cancer seems to be most influenced by presence of LVSI and DOI and not by tumor size as the staging criteria would suggest. These factors are best determined pathologically after radical hysterectomy. This report contains the largest comparison of IB1 and IB2 patients managed by RH. Tumor size failed to predict recurrence or nodal status when stratified by LVSI, DOI, and PI. Treatment decisions based on tumor size alone should be reconsidered.  相似文献   
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