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41.
Objective To evaluate the repeatability and reproducibility of four simplified molecular assays for the diagnosis of Trypanosoma brucei spp. or Leishmania ssp. in a multicentre ring trial with seven participating laboratories. Methods The tests are based on PCR or NASBA amplification of the parasites nucleic acids followed by rapid read‐out by oligochromatographic dipstick (PCR‐OC and NASBA‐OC). Results On purified nucleic acid specimens, the repeatability and reproducibility of the tests were Tryp‐PRC‐OC, 91.7% and 95.5%; Tryp‐NASBA‐OC, 95.8% and 100%; Leish‐PCR‐OC, 95.9% and 98.1%; Leish‐NASBA‐OC, 92.3% and 98.2%. On blood specimens spiked with parasites, the repeatability and reproducibility of the tests were Tryp‐PRC‐OC, 78.4% and 86.6%; Tryp‐NASBA‐OC, 81.5% and 89.0%; Leish‐PCR‐OC, 87.1% and 91.7%; Leish‐NASBA‐OC, 74.8% and 86.2%. Conclusion As repeatability and reproducibility of the tests were satisfactory, further phase II and III evaluations in clinical and population specimens from disease endemic countries are justified.  相似文献   
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OBJECTIVE: Disturbance of any of the ET functions may contribute to the development of otitis media. Sonotubometry measures the ventilatory function using sound. The qualities of sonotubometry as a test for eustachian tube ventilatory function have been studied by various investigators. The development of the method is described in the review, and a summary of the study results is provided to make an estimate of the diagnostic potential of this eustachian tube function test. DATA SOURCES: The English-language literature on the topic was searched systematically by Medline and Pubmed using the following key words: ventilatory function, eustachian tube, sonotubometry, and function test. There were no limits for the year of publication. STUDY SELECTION: Articles that described the method itself (validity, reproducibility, diagnostic value) were studied in detail. DATA EXTRACTION: All the articles described in study selection were used for this review. CONCLUSIONS: The technique of sonotubometry has been improved gradually over the years. The results of sonotubometry are at least as good as those of other function tests. However, because the results still tend to be ambiguous in children and otitis media is most common in this population, the reproducibility and application of sonotubometry must be evaluated further. Sonotubometry has great advantages over other function tests, but it is not used routinely to assess eustachian tube ventilatory function because its value for clinical practice has not yet been adequately demonstrated. The review showed that sonotubometry can be improved further and that efforts to do so seem justified because it forms a particularly promising method to assess eustachian tube function in children with suspected eustachian tube disease.  相似文献   
43.
Proximal row carpectomy in advanced Kienbock's disease   总被引:1,自引:0,他引:1  
This retrospective study assessed the outcomes of 21 patients (16 male and 5 female, mean age 39 years) with advanced Kienbock's disease treated by resection of the proximal carpal row. They were clinically reviewed. The mean follow-up was 67 months, with all but two patients having had a follow-up of 2 years. No or mild pain was being experienced by 13 patients, moderate pain by 3 and severe pain by 5. Grip strength increased from 19 kg pre-operatively to 26 kg postoperatively (or 65% of the normal contralateral side). There was a slight increase of mobility. The DASH score was 22 points (range 0-78) and the Patient Rated Wrist Score (PRWS) was 30 points (range 0-84). Two patients developed Complex Regional Pain Syndrome which was ongoing at the time of review and one developed a superficial wound infection. Proximal carpal row resection arthroplasty gave satisfactory results in patients with advanced Kienbock's disease.  相似文献   
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BACKGROUND: Automatic and semi-automatic algorithms to calculate ejection fraction (EF) from planar radionuclide ventriculography (PRV) have been used for many years in nuclear medicine. Validation of these algorithms is scarce and often performed on outdated versions of the software. Nevertheless, clinical trials where PRV is being used as the 'gold standard' for EF are numerous. Because of the importance attributed to the EF calculated by these programs, the accuracy of the resulting EF was assessed with a dynamic left ventricular physical phantom. METHODS: A dynamic left ventricular phantom was used to simulate 21 combinations of various ejection fractions (7-66%) and end diastolic volumes (27-290 ml). For each combination, a planar radionuclide ventriculograph was acquired, converted to an interfile format and transferred into processing stations with 10 different contemporaneously available commercial algorithms. The gold standard was the 'real' EF of the phantom, derived from the exact volume of the ventricle in end diastolic and end systolic position. Correlation and Bland-Altman analysis was performed between the real EF and the calculated EF. RESULTS: The correlation for all data was excellent (r=0.98), the mean difference was very acceptable (0.98%). Nevertheless, Bland-Altman analysis showed a significant trend in the difference between real and calculated EF, with a growing underestimation for higher ranges of EF, due to an overestimation of background in larger volumes compared to smaller ones. CONCLUSION: The determination of EF from PRV, calculated with commercially available algorithms, correlates closely to the real EF of a dynamic left ventricular phantom. This phantom can be used in the development and validation of algorithms for PRV studies, in software audits and in quality assurance procedures.  相似文献   
47.

Background/purpose

Anorectal malformations occur in 1 per 4,000 live births and represent a surgical challenge. Although critically important, the basic mechanisms of normal anorectal union are incompletely understood. Fgf10 signaling is known to serve a key role in mesenchymal/epithelial interactions in many organ systems including the gastrointestinal tract (GIT). The authors therefore hypothesized that Fgf10 signaling has a central role in normal anorectal development.

Methods

Fgf10 expression in wild-type (Wt) embryos was evaluated using whole-mount in situ hybridization. Wt and Fgf10−/− embryos were harvested from timed pregnant mothers at E12.5 through E17.5 and were analyzed for anorectal phenotype.

Results

Wt development of union between anorectal structures is completed between E12.5 and E13.5 with luminal communication between distal rectal epithelium and anus. Fgf10 is discreetly expressed at E12.5 in the distal rectum. Fgf10−/− mutants show failure of union of the rectum and anus at an early stage (E13.5) and near term (E17.5).

Conclusions

Fgf10 is expressed in the rectum at the time when anorectal continuity is established, indicating a role in normal anorectal development. Fgf10 invalidation (Fgf10−/− mutant) results in a genetically reproducible anorectal malformation phenotype. Fgf10 function is critical for normal anorectal development.  相似文献   
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BACKGROUND: The correction-based therapeutic community (TC) is one of the most described treatment modalities for (substance abusing) incarcerated offenders. The origins and development of the therapeutic community have been traced back to two independent traditions: the American hierarchical concept-based TC and the British democratic Maxwell Jones-type TC. Both branches have developed independently, targeting different people and tackling diverse problems. AIMS: To demonstrate that there are clear and undeniable similarities between the 'two' prison-based therapeutic communities. METHOD: A comparative historical review of the literature and a critical discussion and comparison. RESULTS: The links between the democratic and hierarchical therapeutic communities are summarised under five headings: social learning and behavioural modification; permissiveness and modelling; democracy and hierarchy; communalism and community as method; reality testing and 'acting as if'. CONCLUSIONS: The 'two' correction-based therapeutic communities are on converging pathways. Far from being oppositional models, they can be regarded as being complementary.  相似文献   
50.
Post‐transplant lymphoproliferative disorder (PTLD) may compromise long‐term outcome of lung transplant (LTx) recipients. A case‐control study was performed, comparing LTx recipients with PTLD (n=31) to matched recipients without PTLD (Controls, n=62). Risk factors for PTLD and post‐transplant outcomes were assessed. PTLD prevalence was 3.9%, time to PTLD 323 (166‐1132) days; and 54.8% had early‐onset PTLD versus 45.2% late‐onset PTLD. At LTx, more Epstein‐Barr virus (EBV)‐seronegative patients were present in PTLD (42%) compared to Controls (5%) (P<.0001); most of whom had undergone EBV seroconversion upon PTLD diagnosis. EBV viral load was higher in PTLD versus Controls (P<.0001). Overall, lower hemoglobin and higher C‐reactive protein levels were present in PTLD versus Controls (P<.0001). EBV status at LTx (P=.0073) and EBV viral load at PTLD (P=.0002) were the most important risk determinates for later PTLD. Patients with PTLD demonstrated shorter time to onset of chronic lung allograft dysfunction (CLAD) (P=.0006) and poorer 5‐year survival post‐LTx (66.6% versus 91.5%), resulting in worse CLAD‐free survival (HR 2.127, 95%CI 1.006‐4.500; P=.0483) and overall survival (HR 3.297 95%CI 1.473‐7.382; P=.0037) compared to Controls. Late‐onset PTLD had worse survival compared to early‐onset PTLD (P=.021). Primary EBV infection is a risk for PTLD; which is associated with worse long‐term outcome post‐LTx.  相似文献   
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