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1.
Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them.  相似文献   
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We report an unusual case of myocardial mycotic aneurysm of the left ventricle resulting from a healed myocardial abscess caused by an aortic regurgitant jet lesion. The diagnosis was made during intraoperative transesophageal echocardiography and confirmed by surgical inspection. The echocardiographic features are described.  相似文献   
5.

Introduction and hypothesis

There is a paucity of data on the success of vaginal surgery for severe prolapse. The authors hypothesized that the success rates of total vaginal hysterectomy (TVH) with McCall culdoplasty in women with advanced pelvic organ prolapse (POP) and in women with less severe POP are similar.

Methods

This was a retrospective review of women undergoing TVH with McCall culdoplasty from 2005 to 2014. Advanced POP was defined as exteriorized uterovaginal prolapse with Pelvic Organ Prolapse Quantification (POP-Q) point C, Ba or Bp ≥50% of the total vaginal length. The primary aim was to compare surgical success of TVH with McCall culdoplasty for the repair of advanced POP and less severe POP at ≥1 year.

Results

A total of 311 women were included, 38 with advanced POP and 273 with less severe POP. Women with advanced POP were older (71.6 vs. 61.8 years, respectively; p < 0.0001), but there were no significant differences in the length of follow-up (102.5 vs. 117 weeks, p = 0.2378), success rates (76.3% vs. 68.5%, p = 0.3553) or reoperation rates (2.6% vs. 4%, p > 0.9999) between women with advanced POP and less severe POP, respectively. There was a higher failure rate in the anterior compartment in those with advanced POP (18.4% vs. 6.2%, p = 0.0168), but not in the apical or posterior compartment.

Conclusions

TVH with McCall culdoplasty is equally effective for the treatment of advanced uterovaginal prolapse as for the treatment of less severe POP. Surgeons should consider this traditional surgery for their patients even if they have high-stage uterovaginal prolapse.
  相似文献   
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Aims:

The aim of the study was to measure airway patency objectively during dexmedetomidine sedation under radiographic guidance in spontaneously breathing pediatric patients scheduled for cardiac catheterization procedures.

Subjects and Methods:

Thirty-five patients in the age group 5–10 years scheduled for cardiac catheterization procedures were enrolled. All study patients were given loading dose of dexmedetomidine at 1 μg/kg/min for 10 min and then maintenance dose of 1.5 μg/kg/h. Radiographic airway patency was assessed at the start of infusion (0 min) and after 30 min. Antero-posterior (AP) diameters were measured manually at the nasopharyngeal and retroglossal levels. Dynamic change in airway between inspiration and expiration was considered a measure of airway collapsibility. Patients were monitored for hemodynamics, recovery time and complications.

Statistical Analysis:

Student paired t-test was used for data analysis. P < 0.05 was considered significant.

Results:

Minimum and maximum AP diameters were compared at 0 and 30 min. Nasopharyngeal level showed significant reduction in the minimum (6.27 ± 1.09 vs. 4.26 ± 1.03, P < 0.0001) and maximum (6.51 ± 1.14 vs. 5.99 ± 1.03, P < 0.0001) diameters. Similarly retroglossal level showed significant reduction in the minimum (6.98 ± 1.09 vs. 5.27 ± 1.15, P < 0.0001) and maximum (7.49 ± 1.22 vs. 6.92 ± 1.12, P < 0.0003) diameters. The degree of collapsibility was greater at 30 min than baseline (P < 0.0001). There was a significant decrease in heart rate (P < 0.0001), and the average recovery time was 39.86 ± 12.22 min.

Conclusion:

Even though airway patency was maintained in all children sedated with dexmedetomidine, there were significant reductions in the upper airway dimensions measured, so all precautions to manage the airway failure should be taken.  相似文献   
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OBJECTIVES: To investigate the factors associated with delay in 1) care-seeking (patient delay), and 2) diagnosis by health providers (health system delay), among smear-positive tuberculosis patients, before large-scale DOTS implementation in South India. METHODS: New smear-positive patients were interviewed using a structured questionnaire. RESULTS: Among 531 participants, the median patient, health system and total delays were 20, 23 and 60 days, respectively. Twenty-nine per cent of patients delayed seeking care for > 1 month, of whom 40% attributed the delay to their lack of awareness about TB. Men postponed seeking care for longer periods than women (P = 0.07). In multivariate analysis, the patient delay was greater if the patient had initially consulted a government provider (adjusted odds ratio [AOR] 2.2, P < or = 0.001), resided at a distance >2 km from a health facility (AOR 1.6, P = 0.04), and was an alcoholic (AOR 1.6, P = 0.04). Health system delay was >7 days among 69% of patients. Factors associated with health system delay were: first consultation with a private provider (AOR 4.0, P < 0.001), a shorter duration of cough (AOR 2.6, P = 0.001), alcoholism (P = 0.04) and patient's residence >2 km from a health facility (AOR 1.8, P = 0.02). The total delay resulted largely from a long patient delay when government providers were consulted first, and a long health system delay when private providers were consulted first. CONCLUSION: Public awareness about chest symptoms and the availability of free diagnostic services should be increased. Government and private physicians should be educated to be aware about the possibility of tuberculosis when examining out-patients. Effective referrals for smear microscopy should be developed between private and public providers.  相似文献   
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A reliable identification method was developed for three closely related Curvularia species, which are frequently isolated from human keratomycoses. Since the traditionally used morphological method and the increasingly used internal transcribed spacer (ITS)‐based molecular method proved to be insufficient to discern C. australiensis, C. hawaiiensis and C. spicifera, other molecular targets, such as β‐tubulin, translation elongation factor 1‐α and the nuclear ribosomal intergenic spacer (IGS), were tested. Among them, the use of the highly divergent IGS sequence is suggested and the species‐specific discriminating characters were determined in appropriate reference strains. It was also concluded that C. hawaiiensis and C. spicifera can be predominantly isolated from eye infections among the three species. The in vitro antifungal susceptibility of 10 currently used antifungal agents against 32 Curvularia isolates was also investigated. MICs were determined in each case. Isolates of C. spicifera proved to be less susceptible to the tested antifungals than those of C. hawaiiensis, which underline the importance of the correct identification of these species.  相似文献   
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