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91.
BackgroundCardiomegaly on chest X-ray is an independent predictor of death in individuals with chronic Chagas cardiomyopathy (CCC). However, the correlation between increased cardiothoracic ratio (CTR) on chest X-ray and left ventricular end-diastolic diameter (LVEDD) on echocardiography is not well established in this population.ObjectivesTo assess the relationship between chest X-ray and LVEDD on echocardiography in patients with Chagas disease and its applicability to the Rassi score.MethodsRetrospective study on 63 Chagas disease outpatients who underwent chest X-ray and echocardiography. Cardiomegaly on chest X-ray was defined as a CTR>0.5. LVEDD was analyzed as a continuous variable. ROC curve was used to evaluate the ability of LVEDD in detecting cardiomegaly by chest X-ray, with a cut-off point defined by the highest sum of sensitivity and specificity.ResultsMedian age 61 years [interquartile range 48-68], 56% were women. CCC was detected in 58 patients, five patients had the indeterminate form of Chagas disease. Cardiomegaly was detected in 28 patients. The area under the ROC curve for LVEDD was 0.806 (95%CI: 0.692-0.919). The optimal cut-off for LVEDD was 60 mm (sensitivity = 64%, specificity = 89%). The use of LVEDD on echocardiography as a surrogate for CTR on chest X-ray changed the Rassi score values of 14 patients, with a reduction in the presumed risk in 10 of them.ConclusionLVEDD on echocardiography is an appropriate, highly specific parameter to distinguish between the presence and absence of cardiomegaly on chest X-ray in Chagas disease. (Arq Bras Cardiol. 2021; 116(1):68-74)  相似文献   
92.
This position paper, sponsored by the Asociación Española de Gastroenterología [Spanish Association of Gastroenterology], the Sociedad Española de Endoscopia Digestiva [Spanish Gastrointestinal Endoscopy Society] and the Sociedad Española de Anatomía Patológica [Spanish Anatomical Pathology Society], aims to establish recommendations for performing an high quality upper gastrointestinal endoscopy for the screening of gastric cancer precursor lesions (GCPL) in low-incidence populations, such as the Spanish population. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates different measures to improve the quality of upper gastrointestinal endoscopy in this setting and makes recommendations on how to evaluate and treat the identified lesions. We recommend that upper gastrointestinal endoscopy for surveillance of GCPL should be performed by endoscopists with adequate training, administering oral premedication and use of sedation. To improve the identification of GCPL, we recommend the use of high definition endoscopes and conventional or digital chromoendoscopy and, for biopsies, NBI should be used to target the most suspicious areas of intestinal metaplasia. Regarding the evaluation of visible lesions, the risk of submucosal invasion should be evaluated with magnifying endoscopes and endoscopic ultrasound should be reserved for those with suspected deep invasion. In lesions amenable to endoscopic resection, submucosal endoscopic dissection is considered the technique of choice.  相似文献   
93.
Scott  CF; Sinha  D; Seaman  FS; Walsh  PN; Colman  RW 《Blood》1984,63(1):42-50
The traditional coagulant assay for plasma factor XI suffers from a relatively high coefficient of variation, the need for rare congenitally deficient plasma, and a poor correlation between precision and sensitivity. We have developed a simple functional amidolytic assay for factor XI in plasma using the chromogenic substrate PyrGlu-Pro-Arg- p-nitroanilide (S-2366). After inactivation of alpha 1-antitrypsin, CI inhibitor, and other plasma protease inhibitors with CHCI3, plasma was incubated with kaolin, in the absence of added calcium, which limited the enzymes formed to those dependent on contact activation. Soybean trypsin inhibitor was used to minimize the action of kallikrein on the substrate. Once the reaction was complete, corn trypsin inhibitor was used to inactive factor XIIa, the enzyme generated by exposure of plasma to negatively charged surfaces, which had activated the factor XI. The assay is highly specific for factor XI, since plasma totally deficient in that zymogen yielded only 1%-3% of the enzymatic activity in normal plasma under identical conditions. The requirements for complete conversion of factor XI to XIa in plasma within 60 min were, respectively, factor XII, 0.6 U/ml, and high molecular weight kininogen, 0.2 U/ml. Prekallikrein was not an absolute requirement for complete activation but did accelerate the reaction. The intraassay coefficient of variation was 3.4%, and the mean of 35 normal plasmas was 1.00 U +/- 0.24 SD. In addition, a new rapid radioimmunoassay was devised using staphylococcal protein A as the precipitating agent for a complex of factor XI antigen with monospecific rabbit antibody. The mean was 1.01 U +/- 0.30 SD. The correlation coefficients for amidolytic versus coagulant and amidolytic versus radioimmunoassay were r = 0.95 for the former and 0.96 for the latter. Thus, a simple, accurate amidolytic assay and a radioimmunoassay have been devised for measuring factor XI in plasma that correlate well with the coagulant activity of factor XI, as determined in our laboratory.  相似文献   
94.
95.
In the present study, the fertilizing potential of semen recovered from slaughtered bulls epididymis was evaluated after cryopreservation, by conventional techniques and flow cytometry methods. The cauda epididymal was dissected and sperm were recovered and evaluated for volume, sperm concentration, and membrane and acrosome integrity using a flow cytometer. Sperm fertility potential was tested by in vitro fertilization (IVF). For each bull, three trials of IVF were performed. Before freezing, on average, the sperm concentration was 216 ± 27.5 × 106 sperm/ml. Sperm viability averaged 86.5 ± 4%. The mean percentage of sperm with intact plasma membrane and acrosome before and after cryopreservation was 90.7 ± 2.9% and 90.8 ± 1.9% (P≥0.05), respectively. The fertilization rate using frozen/thawed epididymal semen averaged 64.1 ± 3.9% fertilization with no significant differences between bulls (P>0.05). For the bull considered as control, the fertilization rate was 72.2 ± 4.5%, differing significantly (P>0.05) from the frozen/thawed epididymal semen’s fertilization rate. In conclusion, it is possible to use in vitro techniques with cryopreserved spermatozoa obtained from bull’s epididymis using a controlled rate freezing method with a predetermined freezing curve, and with assessment of sperm’s viability by conventional techniques and flow cytometry methods, together with the fertilizing ability of cryopreserved epididymal spermatozoa.Key Words: Bovine, Cryopreservation, Epididymis, IVF, Semen  相似文献   
96.

Background

There is a hypothesis that the growing use of mobile phones in an inappropriate posture to text and read (text neck) could be a reason for the increasing prevalence of neck pain in the past decade. Before testing if there is an association between text neck and neck pain, it is necessary to develop reliable pragmatic tools appropriate to epidemiological studies.

Objectives

The primary aim of this study was to assess the reliability of the self-perception of text neck, as well as the reliability of physiotherapists’ classification of the text neck.

Methods

The convenience sample was composed of 113 high school students between 18 and 21 years old from a cross-sectional study. As their self-perceived posture, participants had to choose in a questionnaire one of four neck postures of a person texting on a mobile phone. The physiotherapists classified lateral photographs taken with the participants texting on a mobile phone in their habitual posture as 1 (normal), 2 (acceptable), 3 (inappropriate), and 4 (excessively inappropriate).

Results

The results showed that the test–retest reliability of the self-perception was substantial (kappa?=?0.73, 95% CI 0.54 to 0.86). The reliability of the physiotherapists’ responses, according to the photographic analysis considering the three raters, was moderate (kappa?=?0.5, 95% CI 0.39 to 0.61). Seventy-six percent of the participants with appropriate posture in the photographic analysis self-reported an inappropriate posture.

Conclusion

This study showed that the self-perception of the neck posture during mobile phone texting is reliable over time and that the physiotherapists’ classification based on photographic analysis was acceptable for epidemiological studies. Participants had a tendency to report that the posture was worse than it actually was in the photographic analysis performed by the physiotherapists.  相似文献   
97.

Objective

This study investigated the influence of early to moderate primary open angle glaucoma on gait, functional mobility and fall risk.

Methods

Thirty-three participants in the early and moderate stages of primary open angle glaucoma and 34 asymptomatic controls participated in the study. Spatiotemporal gait data were obtained with the GAITRite system and included: velocity, cadence, step length, base of support, swing, stance and double support times. Functional measures included the Timed Up and Go test, the Five-Repetition Sit-To-Stand test and the Dynamic Gait Index. Fall risk was measured using the Physiological Profile Assessment.

Results

The variables contrast sensitivity, proprioception and the Timed Up and Go and Dynamic Gait Index tests were significantly different between groups. In addition, the glaucoma group presented significantly higher risk of falling compared to the control group. Individuals in the early and moderate stages of primary open glaucoma presented mobility and sensory deficits that increase the risk of falling.

Conclusions

The results of this study suggest that adding the Timed Up and Go and Dynamic Gait Index tests to routine physical therapy assessment of individuals with early glaucoma could be useful. Rehabilitation programs should focus on maintaining and/or improving mobility and balance, and prevention of falls in this population.  相似文献   
98.
99.

OBJECTIVE:

to verify associations between overweight and the characteristics of young adult students to support nursing care.

METHOD:

case-control study conducted with young adults from public schools. The sample was composed of 441 participants (147 cases and 294 controls, with and without excess weight, respectively). Sociodemographic and clinical characteristics were collected together with exposure factors and anthropometrics. Multiple logistic regression was used. The study received Institutional Review Board approval.

RESULTS:

statistically significant association with overweight: non-Caucasian, having a partner; weight gain during adolescence, mother''s excess weight, the use of obesogenic medication, augmented diastolic blood pressure, of abdominal circumference and waist/hip ratio. In addition to these, schooling and weight gain during childhood were also included in the multivariate analysis. After adjustment, the final model included: having a partner, weight gain during adolescence, augmented diastolic blood pressure and abdominal circumference.

CONCLUSION:

the analysis of predictor variables for excess weight among young adult students supports nurses in planning and developing educational practices aimed to prevent this clinical condition, which is a risk factor for other chronic comorbidities, such as cardiovascular diseases.  相似文献   
100.
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