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OBJECTIVE: Little is known about the interactions of sports-related demands and human body, in particular on musculoskeletal features, during growth. Focusing on the relationship between soccer and lower limb alignment, we examined the hypothesis that varus knee deviation is more prevalent among high-performance pediatric and adolescent soccer players. DESIGN: Cross-sectional study with focused sampling. SETTING: First league sports clubs. PARTICIPANTS: 106 male child/adolescent soccer players aged 10 to 21 years and 68 age-matched tennis players. INTERVENTIONS: All athletes completed a demographic questionnaire and underwent physical examinations, which included height, weight, generalized laxity, knee, ankle, foot and spine axis, hip range of motion, tibial torsion, Q angle, foot navicular height, and progression angle. MAIN OUTCOME MEASUREMENT: Varus/valgus axis was determined by the intercondylar intermalleolar distance while standing. Soccer and tennis players were compared on knee axis and other outcome variables by analysis of covariance, adjusting for age and by t-tests within age groups. RESULTS: A significantly higher prevalence of knee varus was found among the soccer players compared to that among the tennis players. The difference in intracondylar distance was statistically significant after the age of 13 years (P < 0.001). In addition, compared to tennis players, soccer players had higher foot arches, decreased hip external rotation and increased external tibial torsion. CONCLUSIONS: Varus knee axis deviation was more common among children and adolescent soccer players than among tennis players. The prevalence was more pronounced among players aged 13 years or older. Further research is needed to explore the rationale of this phenomenon.  相似文献   
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PURPOSETo evaluate the effect of MR contrast dose versus delayed imaging time on the detection of metastatic brain lesions based on lesion size.METHODSContrast MR examinations with gadoteridol were obtained in 45 patients with brain metastases. The patients were divided into two groups: 16 received cumulative standard dose (0.1 mmol/kg) and 29 received cumulative triple dose (0.3 mmol/kg). Both groups were evaluated at two dose levels (lower dose and higher dose) with two separate injections. Each patient received an initial bolus injection of either 0.05 (cumulative standard dose) or 0.1 (cumulative triple dose) mmol/kg of gadoteridol to reach the lower-dose level and underwent imaging immediately and 10 and 20 minutes later. Thirty minutes after injection, an additional bolus injection of 0.05 (cumulative standard dose) or 0.2 (cumulative triple dose) mmol/kg was administered to reach the cumulative higher-dose level (cumulative standard dose, 0.1 mmol/kg; cumulative triple dose, 0.3 mmol). Images were acquired immediately.RESULTSThere was no difference in the detection rate for lesions larger than 10 mm among T2-weighted, lower-dose immediate and delayed, or immediate higher-dose images in both study groups. Lesions smaller than 10 mm had improved detection with delayed imaging in both study groups; however, the immediate higher-dose studies still had the highest detection rate.CONCLUSIONIn the evaluation of small central nervous system metastases, either delayed imaging after the injection of standard contrast dose or higher contrast dose may improve their detection, and therefore affect clinical management. Higher contrast dose (cumulative triple dose) studies appear to be more effective than delayed imaging with standard dose.  相似文献   
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Hoffman  Amnon  Alfon  Jose  Siegal  Tzony  Siegal  Tali 《Pharmaceutical research》1994,11(4):536-540
The purpose of this investigation was to determine whether paraplegia induced by neoplastic cord compression affects the pharmacodynamics of phenobarbital general anesthesia or of pentylenetet-razol (PTZ)-induced convulsions. Paraplegic rats harboring a thora-columbar epidural tumor, or an identical hindlimb tumor mass, received an i.v. infusion of phenobarbital until the onset of anesthesia. At that point, the phenobarbital concentrations in the CSF and serum were measured. Similarly, PTZ was infused until the onset of maximal seizures. It was found that changes related to systemic tumor growth and newly developed paraplegia due to neoplastic spinal cord compression did not attenuate the pharmacodynamics of phenobarbital. However, sustained paraplegia of 4 days duration reduced CNS sensitivity to the hypnotic action of the barbiturate as evidenced by the higher cerebrospinal fluid phenobarbital concentration required to induce anesthesia (170 ± 31 vs 125 ± 20 mg/L; P < 0.05). On the other hand, sustained paraplegia did not affect brain threshold concentration for PTZ-induced seizures.  相似文献   
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OBJECTIVE: The study was designed to investigate obstetric risk factors and pregnancy outcome of patients with pruritic urticarial papules and plaques of pregnancy (PUPPP). METHODS: A population-based study comparing all pregnancies of women with and without PUPPP was conducted. Deliveries occurred during the years 1988-2002 at the Soroka University Medical Center. A multivariable logistic regression model was constructed in order to find independent risk factors associated with PUPPP. RESULTS: During a 15-year period, 159 197 deliveries took place. PUPPP complicated 42 (0.03%) of all pregnancies. Using a multivariable analysis, the following conditions were significantly associated with PUPPP: multiple pregnancies (odds ratio (OR) = 4.9, 95% confidence interval (CI) 1.7-14.1), hypertensive disorders (OR = 2.2, 95% CI 1.1-4.7), and induction of labor (OR = 7.6, 95% CI 4.0-14.5). Higher rates of 5-minute Apgar scores lower than 7 (OR = 8.0, 95% CI 4.4-14.9) and of cesarean deliveries (OR = 2.9, 95% CI 1.5-5.6) were noted in the PUPPP as compared to the comparison group. While investigating other perinatal outcome parameters such as oligohydramnios, intrauterine growth restriction, meconium-stained amniotic fluid and perinatal mortality, no significant differences were observed between the groups. CONCLUSION: Pruritic urticarial papules and plaques of pregnancy is a condition significantly associated with multiple pregnancies, hypertensive disorders, and induction of labor. Perinatal outcome is comparable to pregnancies without PUPPP.  相似文献   
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STUDY OBJECTIVES: To compare the oxygen pulse curve (O(2)P-C) as measured during cardiopulmonary exercise testing (CPET) with left ventricular (LV) ejection fraction (LVEF) rest-exercise response as measured by multigated equilibrium (99m)Tc radionuclide cineangiography (MUGA) in patients with different degrees of ischemic heart disease (IHD). PATIENTS: Forty-six patients (39 men and 7 women; mean plus minus 1 SD age, 59.2 plus minus 11 years) with IHD, with no hypertrophic, valvular, or pericardial disease. METHODS: A supine bicycle ergometer with increments of 25 W every 2 min was used for MUGA, and an electronically braked cycle ergometer was used for upright symptoms-limited CPET. Exercise was increased by 10 to 20 W/min until the target heart rate (HR) was reached (similar peak HR for both studies). MEASUREMENTS AND RESULTS: The O(2)P-C was scored on a 10-point scale as follows: type A, normal curve (10 points); type B, normal-shaped curve with low values (8 points); type C, low and flat curve (5 points); type D, descending curve (3 points). Findings for the MUGA study were classified into four groups by the degree of ischemic response: group 1 (control), normal diastolic function (n = 10), LVEF > 55%, LVEF during exercise minus LVEF at rest [DeltaLVEF] greater-than-or-equal 5%; group 2, mild ischemia (n = 10), LVEF > 55%, < 0 DeltaLVEF < 5%, diastolic dysfunction at exercise (prominent "A" waves); group 3, LV dysfunction (n = 9), LVEF < or = 35% at rest; and group 4, significant ischemia (n = 17), LVEF > 55%, DeltaLVEF < 0, diastolic dysfunction. A highly significant relationship between the O(2)P-C score and the MUGA grouping was observed by Fisher's Exact Test and Pearson's linear regression line (p < 0.001; R = - 0.89). CONCLUSIONS: Exercise-responded O(2)P-C might serve as a good noninvasive, physiologically based, parameter to distinguish between IHD patients with normal and impaired LV function.  相似文献   
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