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101.
We investigated the effects of combined lower body (LB) endurance and upper body (UB) resistance training on endurance, strength, blood lipid profile and body composition in active older men. Ten healthy still active men (73 ± 4 years, peak: 36 (31–41) ml min−1 kg−1) were tested before and after 14 weeks of combined training (3 times week−1). Training consisted of 3 × 12 min of high intensity interval training on a bicycle for endurance interspersed by 3 × 12 min of UB resistance exercises. peak during leg cycling and arm cranking, isokinetic torque of knee extensor and shoulder abductor and the cross-sectional area (CSA) of several muscles from UB and LB were measured. Sagittal abdominal diameter (SAD) and abdominal fat area were measured on MRI scans. Total body composition was assessed by hydrostatic weighing (HW) and dual-energy X-ray absorptiometry (DEXA). Blood lipid profile was assessed before and after training. By the end of the training period, peak (l min−1) increased significantly by 9 and 16% in leg cycling and arm cranking tests, respectively. Maximal isokinetic torque increased both for the knee extensor and shoulder abductor muscle groups. CSA increased significantly in deltoid muscle. Percentage of body fat decreased by 1.3% (P < 0.05) and abdominal fat and SAD decreased by 12 and 6%, respectively (P < 0.01). There was also a significant decrease in total cholesterol and low-density lipoprotein. Thus, combined LB endurance and UB resistance training can improve endurance, strength, body composition and blood lipid profile even in healthy active elderly.  相似文献   
102.
 This multicenter study has revealed that treating a woven polyethylene terephthalate (polyester) ligament with a radiofrequency (RF)-generated glow discharge (RFGD) produces marked benefits in terms of increased cell attachment and proliferation on the implant surface. In vitro tests of the same material revealed that the number of synovial fibroblasts attached to the treated samples after 14 days was four times that of the untreated material. Many of the cells were spread over the surface of a single filament, and some formed bridges between one filament and the next. The incorporation of [3H]-thymidine by synovial stromal cells (a measure of the amount of cell division) growing on the treated material was five times that on the untreated samples. The amount of DNA present on the treated material was also found to be almost an order of magnitude greater than that on untreated samples. This increase in cell attachment and proliferation is almost certainly related to a notable increase in wettability of the polyester surface induced by treatment. Mechanical tests revealed that, for ligaments with a nominal ultimate tensile strength of 2100 N, RF-generated glow treatment reduced the ligament's strength by 12% but increased its stiffness by 15%. After a medium-term fatigue test (10.8 million cycles), however, there appeared to be recovery of the mechanical properties, with the strength and stiffness of untreated and treated samples being essentially the same. After exhaustive fatigue tests (more than 62 million cycles) the residual strength of the treated ligaments was only 9% lower than that of the unfatigued and untreated ligaments. Received: July 1, 2002 / Accepted: October 22, 2002 Acknowledgments. The authors thank Xiros plc for providing ligament samples. We also thank the following individuals for their contribution to the work described in this study: Mr. Les Johnson, School of Textile Industries, University of Leeds, for carrying out wettability tests; Dr. David Woolley, Department of Medicine, University of Manchester for supplying cells for the study at Yorkshire Regional Tissue Bank; Mr. John Tresnan, Xiros plc, for carrying out the mechanical tests. We especially acknowledge the contribution of Sangjin Kang to the work carried out at the School of Biochemistry and Molecular Biology, University of Leeds. Offprint requests to: J.R.J. Rowland  相似文献   
103.
We examined the oxygen uptake (VO2) and carbon dioxide output (VCO2) during completion of a circuit developed for testing fire fighters and related performance time to laboratory measures of fitness. Twenty-two healthy university students (ten women) were trained in the tasks then performed the circuit as quickly as possible. Breath-by-breath gas exchange and heart rate were continuously measured with a portable system. Median circuit time was 6:13 (min:s, 25-75% = 5:46-6:42) for men and 7:25 (25-75% = 6:49-10:21) for 8 women finishers (P = 0.023), and VO2 averaged 68 and 64% VO2max for the men and women during the circuit. Both men and women had high respiratory exchange ratios (>1.0) suggesting marked anaerobic energy contribution. Physiological variables associated with circuit time were assessed by backward stepwise regression yielding a significant model that included only peak work rate during arm cranking exercise as a function of circuit completion time across men and women combined (P < 0.001). For men, but especially for women, the time required for the simulated victim drag (68.2 kg mannequin) was positively correlated with total time to complete the other circuit elements (r = 0.51, r = 0.96 respectively). The simple correlation between circuit time and VO2max (mL/kg/min) revealed poor relationships for men (r = -0.37, P > 0.05) and women (r = 0.20, P > 0.05). These data demonstrated that upper body fitness as reflected by peak work rate during arm cranking correlated with total circuit time for the men and women in our population sample.  相似文献   
104.
The purpose of this study was to determine the effect of vertical whole-body vibration (WBV) on heart rate (HR), mean arterial pressure (MAP), femoral artery blood flow (FBF), and leg skin temperature (LSktemp) during static exercise. These parameters were examined: seated next to the WBV device (passive, unloaded), with feet secured onto the WBV platform (knees 90° flexion) and while standing in a semi-squat position (static, loaded, knees 120° flexion); both with and without WBV. Conditions involved 1 min bouts separated by 1 min rest, repeated 15 times followed by 10 min recovery. WBV in the seated condition had no effect on the responses examined. The static semi-squat without WBV increased MAP 9 mmHg (P < 0.05) with no significant effect on HR, FBF, or LSktemp. Similarly, WBV static semi-squat increased MAP 8–14 mmHg (P < 0.05), FBF 135–180 mL/min, and LSktemp 1.8–3.1°C (P < 0.05). However, only the LSktemp was increased above the no-WBV semi-squat position (P < 0.05). The addition of WBV to repeated intermittent static semi-squats does not appear to be a significant cardiovascular stressor.  相似文献   
105.
Previous research suggests that individuals use a sense of effort, more than proprioceptive feedback, to gauge force production in their upper limbs. We have adopted an isometric force matching task to determine if force asymmetry between lower limbs during bilateral force production results from a neural mechanism related to sense of effort. We hypothesized that subjects attempting to produce equal lower limb forces would generate equal percentages of their bilateral maximum voluntary strength rather than equal absolute limb forces. Ten subjects performed isometric lower limb extensions on an exercise machine. Subjects attempted to match forces in their lower limbs at three different submaximal levels (20, 40, and 60% of their weaker limb peak force during bilateral maximum voluntary contraction). Subjects received visual feedback of only the target and stronger limb force. Results showed that subjects consistently produced less force in their weaker limb during all force matching levels when normalized to their unilateral maximum voluntary contraction force (ANOVAs 20% P = 0.0473, 40% P = 0.0012, 60% P = 0.0007). As predicted by our hypothesis, normalizing force magnitudes by bilateral maximum voluntary contraction forces revealed no significant differences between limbs at all force levels (ANOVA P = 0.8490). Regardless of whether humans produce maximal or submaximal forces, limb force asymmetry appears to be related to neural factors rather than differences in mechanical capabilities between the limbs. Our findings have implications for bilateral asymmetries during movement in healthy and neurologically impaired populations.  相似文献   
106.
Hooten WM  Qu W  Townsend CO  Judd JW 《Pain》2012,153(4):915-923
Strength training and aerobic exercise have beneficial effects on pain in adults with fibromyalgia. However, the equivalence of strengthening and aerobic exercise has not been reported. The primary aim of this randomized equivalence trial involving patients with fibromyalgia admitted to an interdisciplinary pain treatment program was to test the hypothesis that strengthening (n=36) and aerobic (n=36) exercise have equivalent effects (95% confidence interval within an equivalence margin ± 8) on pain, as measured by the pain severity subscale of the Multidimensional Pain Inventory. Secondary aims included determining the effects of strengthening and aerobic exercise on peak Vo(2) uptake, leg strength, and pressure pain thresholds. In an intent-to-treat analysis, the mean (± standard deviation) pain severity scores for the strength and aerobic groups at study completion were 34.4 ± 11.5 and 37.6 ± 11.9, respectively. The group difference was -3.2 (95% confidence interval, -8.7 to 2.3), which was within the equivalence margin of Δ8. Significant improvements in pain severity (P<.001), peak Vo(2) (P<.001), strength (P<.001), and pain thresholds (P<.001) were observed from baseline to week 3 in the intent-to-treat analysis; however, patients in the aerobic group (mean change 2.0 ± 2.6 mL/kg/min) experienced greater gains (P<.013) in peak Vo(2) compared to the strength group (mean change 0.4 ± 2.6 mL/kg/min). Knowledge of the equivalence and physiological effects of exercise have important clinical implications that could allow practitioners to target exercise recommendations on the basis of comorbid medical conditions or patient preference for a particular type of exercise. This study found that strength and aerobic exercise had equivalent effects on reducing pain severity among patients with fibromyalgia.  相似文献   
107.
108.
The Strength and Difficulties Questionnaire (SDQ) is a brief screening instrument for assessing emotional and behavioural problems in children and adolescents. This study examined the factor structure and validity of the self‐report original English version of the SDQ and four of its many translations (German, Cypriot Greek, Swedish, and Italian). A total of 2418 adolescents from five European countries (Germany, Cyprus, England, Sweden, Italy), ages 12 to 17 years, participated. The sample was drawn from general (school) populations. In addition to the SDQ, all participants completed the Spence Children's Anxiety Scale (SCAS), a measure of anxiety symptoms. The internal consistency and validity of the SDQ total difficulties were good for most countries. Confirmatory factor analysis showed that both five‐ and three‐factor models provided good fit for the whole sample; however, the three‐factor model fit somewhat better than the five‐factor model. The factor structure differed across countries, with the three‐factor model showing better fit indices in Cyprus, whereas the five‐factor model fitted better in Germany. Fit indices for the UK, Sweden, and Italy were poor for both models. When the reversed items were removed, the goodness‐of‐fit improved significantly for the total sample and in each country. It is therefore recommended that the reversed items be removed or re‐worded in future studies. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
109.

Introduction

There is an increase in the number of anabolic-steroid (AS)-abusing trainees, who suffer from sports injuries, needing reconstruction surgery. Rupture of the distal biceps brachii tendon is a common injury in this group.

Purpose

The study aimed to investigate the effect of AS abuse in the anatomic reconstruction of the ruptured distal biceps brachii tendon along with an immediate range-of-motion postoperative protocol.

Methods

We conducted an observation study of 17 male athletes suffering from distal biceps tendon ruptures. Six of them reported that they abused AS (group A), whereas the non-users comprised group B (n = 11). Both groups were treated with the modified single-incision technique with two suture anchors and an immediate active range-of-motion protocol postoperatively. Follow-up was at 4, 16 and 52 weeks postoperatively, with a final follow-up at 24 months.

Results

Follow-up at 4, 16 and 52 weeks postoperatively showed a statistical significance in favour of group A for therapeutic outcomes concerning flexion, supination, pronation, Disabilities of the Arm, Shoulder and Hand (DASH) Disability Symptom Scores, Mayo Elbow Performance Elbow Scores and isometric muscle strength tests for both flexion and supination. Twenty-four months postoperatively, statistical significance in favour of group A was recorded in isometric muscle strength tests for both flexion and supination and also in DASH Disability Symptom Score.

Discussion

The results of our study suggest that there is a correlation between the effect of AS and the quicker and better recuperation and rehabilitation observed in group A. Nonetheless, these results must be interpreted with caution, and further in vivo research is needed to confirm these findings.  相似文献   
110.
PurposeThis review aimed to investigate the effects of cryotherapy on the functional capacity parameters of athletes, such as muscular strength, flexibility, neuromuscular control, and balance.MethodsA computerized search of EBSCO Host databases, Proquest, Medline, SportDiscus, CinahlPlus, Health Source Nursing/Academic Edition, Academic Search Complete, and GoogleScholar databases was performed to identify clinical trials with a focus on cryotherapy applications in sport. Thekeywords used were “cryotherapy,” “sports,”“strength,”“flexibility,” and “proprioception.”Study selectionRandomized control trials and randomized crossover studies of healthy athletes were included in this review. The methodological quality of the studies was assessed by the validation criteria given by Furlan et al (2009).ResultsA total of 50 randomized controlled trials (RCTs) and randomized crossover studies met the above criteria and were included in the final analysis. The studies available indicate that there is no strong research evidence to suggest that cryotherapy can definitely influence joint strength and neuromuscular control. The only positive effect of cryotherapy appears to be an improvement in joint flexibility.ConclusionsLimited and equivocal evidence is available to address the effect of cryotherapy on muscular function. The only evidence-based positive impact after the applications of cryotherapy is improved joint flexibility. Despite the extensive use of cryotherapy in sports, further research is needed to document the actual effects of cryotherapy applications on athletes' functional performance and rehabilitation parameters.  相似文献   
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