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11.
Investigations in the physiological demands of soccer have identified that a significant percentage of energy production in match performance is provided through the aerobic pathways. It is therefore important to assess maximal oxygen uptake (VO2Max) of players in order to evaluate their aerobic fitness status and optimize their physical conditioning. However, it is also important to consider the variation of (VO2Max) profiles for soccer players, with differences having been identified in terms of playing position as well as playing style. This paper reviews the academic literature between 1996 and 2006 and reports on the methodologies employed and the values obtained for stature, body mass and (VO2Max) profiles of soccer players of different positions in professional Brazilian clubs at U-17, U-20 and First Division levels. Indirect measurements accounted for the majority of tests conducted at U-17 (70%) and U-20 (84.6%) levels whereas at First Division level almost half of the (VO2Max) evaluations were performed by direct measurements (47.8%). The mean (VO2Max) profiles obtained for outfield players in U-17 was 56.95 ± 3.60 ml·kg-1·min-1, 58.13 ± 3.21 ml·kg-1·min-1 for U-20 players and 56.58 ± 5.03 ml·kg-1·min-1 for First Division players. In Brazil, the U-20 players appear to have highest VO2Max values, however the profiles reported for all outfield positions in U-17 and First Division levels are often lower than those reported for the same category of players from other countries. This may be a reflection of the style of play used in Brazilian soccer. This is further emphasized by the fact that the playing position with the highest VO2Max values was the external defenders whereas most findings from studies performed in European soccer indicate that midfielders require the highest VO2Max values.

Key points

  • Physical and physiological differences exist between Brazilian soccer and European soccer.
  • Players in Brazil appear to be shorter in stature, similar in body mass and have a lower overall aerobic capacity to their European equivalents
  • In Brazil, there seems to be a physical development phase for players at U-20 level which prepares them for the demands at First Division level.
Key words: Soccer, maximal oxygen uptake, playing positions  相似文献   
12.

Introduction

Anatomical and functional influences on gastric bypass (GBP) results are often poorly evaluated and not yet fully understood.

Purpose

The purpose of this study is to evaluate the influence of the gastric pouch volume and its emptying rate on long-term weight loss and food tolerance after GBP.

Materials and Methods

Weight loss, food tolerance, pouch volumetry (V) by three-dimensional reconstruction, and pouch emptying rate by 4 h scintigraphy were evaluated in 67 patients. Cutoffs were identified for V and retention percentage (%Ret) at 1 h (%Ret1). From these parameters, the sample was categorized, looking for associations between V, %Ret, weight loss, and food tolerance, assessed by a questionnaire for quick assessment of food tolerance (SS).

Results

PO median follow-up time was 47 months; median V was 28 mL; %Ret at 1, 2, and 4 h were 8, 2, and 1%, respectively. There were associations between V ≤ 40 mL and higher emptying rates up to 2 h (V ≤ 40 mL: %Ret1 = 6, %Ret2 = 2, p = 0.009; V > 40 mL: %Ret1 = 44, %Ret2 = 13.5, p = 0.045). An association was found between higher emptying speed in 1 h and higher late weight loss (WL), represented by lower percentage of excess weight loss (%EWL) regain (p = 0.036) and higher %EWL (p = 0.033) in the group with %Ret1 ≤ 12%, compared to the group %Ret1 ≥ 25%. Better food tolerance (SS > 24), was associated with lower %Ret1 (p = 0.003).

Conclusion

Smaller pouch size is associated with a faster gastric emptying, greater WL maintenance, and better food tolerance. These data suggest that a small pouch with rapid emptying rate is an important technical parameter for good outcomes in GBP.
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Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2.  相似文献   
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Forensic Toxicology - We have developed and validated a high-sensitivity method to quantify lysergic acid diethylamide (LSD) and 2-oxo-3-hydroxy-LSD (OH-LSD) in oral fluid samples using...  相似文献   
18.
Background Whole Slide Imaging (WSI) is an alternative method to light microscopy (LM). However, few studies have compared the diagnostic agreement between WSI and LM, especially to grade oral epithelial dysplasia (OED). The purpose of this study was to evaluate the variability in grading OED by the World Health Organization grading system, using WSI and conventional LM, and to investigate whether the access to clinical information, and psychologic or physical states of the pathologists could interfere with the diagnosis. Material and Methods eleven experienced pathologists from seven Brazilian universities independently evaluated twenty-five OED cases. The analyses were performed in duplicate for each method, with an interval of at least 30 days, and the time consumed in each analysis was measured. Physical and psychologic states were evaluated by blood pressure levels, heart rate and two questionnaires: State-Trait Anxiety Inventory and Perceived Stress Scale. Clinical information was provided after the second evaluation using WSI and the pathologist could change their diagnostic decision or not. Results LM showed a higher inter-examiner agreement (k=0.53) than WSI (k=0.45) and a smaller time consumed by the pathologists (mean of 65.53 seconds compared to 91.02 seconds in WSI). In the first analysis using conventional microscopy, there was a positive correlation between kappa values and anxiety (r=0.47, p=0.02), and stress (r=0.64, p<0.01), and an inverse correlation with heart rate (r=-0.48, p=0.02). In the digital analysis, there was also a positive correlation between kappa values and anxiety (r=0.75, p<0.001). After clinical information was given, there was a slight change in 11.3% of the cases, and a great discrepancy in 1.1% of the cases, mainly increasing the OED grade. Conclusions both microscopy systems had similar results, although LM had slightly higher kappa values, and WSI was more time consuming. Key words:Pathology, microscopy, diagnosis, leukoplakia oral, anxiety.  相似文献   
19.
Clinical Oral Investigations - To compare the root filling quality, the sealer extrusion, and the healing rates of apical lesions addressed via two endodontic treatment approaches. The hypothesis...  相似文献   
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