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21.
Neuroradiology - In this study, we aimed to develop a novel prediction model to identify patients in need of a non-contrast head CT exam during emergency department (ED) triage. We collected data...  相似文献   
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Foot-and-mouth disease virus (FMDV) antigenic-match between vaccine and field viruses has traditionally been estimated in vitro by computing the r1 value using virus neutralization test (VNT) or ELISA titers. In this study we compared the accuracy in predicting cross-protection between the r1 value estimated by VNT and two recently developed tests that measure IgG subtypes and avidity. Data analyzed consisted of 64 serum samples from FMDV A24/Cruzeiro vaccinated bovines challenged with the heterologous A/Argentina/2001 strain and evaluated for podal generalization. We computed the tests sensitivity (Se), specificity (Sp), and receiving operating characteristics (ROC) curve. The heterologous IgG1/IgG2 ratio was the most accurate test (Se = 0.71, Sp = 0.98), followed by heterologous IgG1 (Se = 0.53, Sp = 0.96), VNT (Se = 0.47, Sp = 1.00), whereas r1 accuracy was substantially low (Se = 0.41, Sp = 0.81). Because sensitivity of individual tests was limited, we argue that two or more of the tests should be used in combination to produce accurate estimates of protection.  相似文献   
24.
Despite high vaccination coverage rates, pertussis continues to be a global concern, with increased incidence widely noted. The current pertussis epidemiologic situation has been mainly attributed to waning immunity and pathogen adaptation. To improve the disease control, a new generation of vaccines capable to overcome those weaknesses associated to the current vaccines need to be developed. Previously we have demonstrated that the outer membrane vesicles obtained from the recombinant Bordetella pertussis strain expressing PagL enzyme (OMVsBpPagL) are good vaccine candidates to protect against pertussis. In this work the OMVsBpPagL formulated with diphtheria and tetanus toxoids (TdapOMVsBpPagL) was used to evaluate its capacity to offer protection against Argentinean clinical isolates and to induce long-term immunity. To these aims BALB/c mice were immunized with TdapOMVsBpPagL and challenged with sublethal doses of the clinical isolate Bp106 selected as a representative circulating isolate. Comparisons with a current commercial Tdap vaccine used at a dose in which pertussis toxin level was equivalent to that of TdapOMVsBpPagL were performed. With the normalized doses of both vaccines we observed that TdapOMVsBpPagL protected against the clinical isolate infection, whereas current commercial Tdap vaccine showed little protection against such pathogen. Regarding long-term immunity we observed that the TdapOMVsBpPagL protective capacity against the recommended WHO reference strain persisted at least 9 months. In agreement with these results TdapOMVsBpPagL induced Th1 and Th2 immune response. In contrast, commercial Tdap induced Th2 but weak Th1 responses. All results presented here showed that TdapOMVsBpPagL is an interesting formulation to be considered for the development of novel acellular multi-antigen vaccine.  相似文献   
25.

Background

Laparoscopic approach is related to, among others, educing abdominal wall complications such as incisional hernia (IH). However, there are scarce data concerning laparoscopic colorectal surgery (LCRS). The aim of this study was to evaluate related factors and incidence of IH following this approach.

Methods

A retrospective analysis of consecutive patients who underwent colorectal surgery with laparoscopic approach in a single center was performed. Patients with a minimum follow-up of 6 months, and also converted to open surgery were included. Uni- and multi-variate analyses were performed using the following variables: age; gender; type of surgery (left, right, total, or segmental colectomy); comorbidities [diabetes and chronic pulmonary obstructive disease (COPD)]; previous surgery; colorectal disease (benign and malignant); operative time; surgical site infection (SSI); and body mass index (BMI). Midline incisions (right colectomy) and off-midline incisions (left colectomies and rectal resections) were also compared.

Results

During a period of 12 years, 1051 laparoscopic colorectal surgeries were performed. The incidence of IH was 6 % (n = 63). Univariate analysis showed that BMI > 30 kg/m2 [p < 0.01, OR: 2.3 (1.3–4.7)], SSI [p < 0.01, OR: 6.5 (3.4–12.5)], operative time >180 min [p < 0.01, OR: 2.1 (1.2–3.6)] and conversion to open surgery (p = 0.01, OR: 2.4 [1.1–5.0]) were related to incisional hernias. BMI and SSI have a statistically significant relation with the incidence of IH in multivariate analysis (p < 0.01). No statistical difference between right and left colectomy was observed (6.6 vs. 6.4 %, respectively).

Conclusion

The incidence of IH after LCRS seems to be acceptable. BMI over 30 kg/m2 and SSI are strongly associated to this complication.  相似文献   
26.

Objectives

Despite nanofill and submicron composites’ aim to provide high initial polishing combined with superior smoothness and gloss retention, the question still remains whether clinicians should consider using these new materials over traditional microhybrids. The aim of this paper was to systematically review the literature on how nanofills and submicrons react to polishing procedures and surface challenges in vitro compared with microhybrids. The paper has also given an overview of the compositional characteristics of all resin composites and polishing systems whose performance was presented herein.

Data

The database search for the effect of filler size on surface smoothness and gloss of commercial composites retrieved 702 eligible studies. After deduplication, 438 records were examined by the titles and abstracts; 400 studies were excluded and 38 articles were assessed for full-text reading. An additional 11 papers were selected by hand-searching. In total, 28 articles met inclusion criteria and were included in the study.

Sources

The databases analyzed were MEDLINE/PubMed, ISI Web of Science, and SciVerse Scopus.

Study selection

Papers were selected if they presented a comparison between nanofill or submicron and microhybrid composites with quantitative analysis of smoothness and/or gloss on baseline and/or after any aging protocol to assess smoothness and gloss retention. Only in vitro studies written in English were included.

Conclusions

There is no in vitro evidence to support the choice for nanofill or submicron composites over traditional microhybrids based on better surface smoothness and/or gloss, or based upon maintenance of those superficial characteristics after surface challenges.  相似文献   
27.
BACKGROUND The impact of obesity on surgical outcomes in elderly patients candidate for liver surgery is still debated.AIM To evaluate the impact of high body mass index(BMI) on perioperative and oncological outcome in elderly patients(> 70 years old) treated with laparoscopic liver resection for hepatocellular carcinoma(HCC).METHODS Retrospective multicenter study including 224 elderly patients(> 70 years old) operated by laparoscopy for HCC(196 with a BMI < 30 and 28 with BMI ≥ 30), o...  相似文献   
28.
29.
The viscacha (Lagostomus maximus maximus) is a rodent with photoperiod‐dependent seasonal reproduction. The aim of this work was to study the morphological variations of the prostate during periods of maximal (summer, long photoperiod) and minimal (winter, short photoperiod) reproductive activity. Prostates of adult male viscachas were studied by light and electron microscopy, immunohistochemistry for androgen receptor, and morphometric analysis. The prostate consisted of two regions: peripheral and central. The peripheral zone exhibited large adenomeres with a small number of folds and lined with a pseudostratified epithelium. The central zone had small adenomeres with pseudostratified epithelium and the mucosa showed numerous folds. The morphology of both zones showed variations during periods of maximal and minimal reproductive activity. The prostate weight, prostate‐somatic index, luminal diameter of adenomeres, epithelial height and major nuclear diameter decreased during the period of minimal reproductive activity. Principal cells showed variations in their shape, size and ultrastructural characteristics during the period of minimal reproductive activity in comparison with the active period. The androgen receptor expression in epithelial and fibromuscular stromal cells was different between the studied periods. Our results suggest a reduced secretory activity of viscacha prostate during the period of minimal reproductive activity. Thus, the morphological variations observed in both the central and peripheral zones of the viscacha prostate agree with the results previously obtained in the gonads of this rodent of photoperiod‐dependent reproduction. Additionally, the variations observed in the androgen receptors suggest a direct effect of the circulating testosterone on the gland. Anat Rec, 298:1919–1931, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
30.
OBJECTIVE: To collect and review all cases of sclerodermatous chronic graft-vs-host disease from January 1, 1982, through December 31, 2000. SETTING: University hospital in Madrid, Spain. PATIENTS: During the study period, 493 allogenic bone marrow transplantations were performed. Sclerotic lesions developed in 17 patients. RESULTS: Sclerotic lesions appeared after a mean of 529 days. Previously, 10 (59%) of 17 patients showed a leopard-skin eruption. Sclerosis was generalized in 12 patients and localized in 5. Nine patients presented with rippling of the skin and 8 with lichen sclerosus lesions. We found no anti-Scl-70 or anti-centromere antibodies. Results of histological analysis showed pandermal or deep-dermal sclerosis, slight vacuolar degeneration of the basal cell layer, and follicular damage with follicular plugs. In 6 (50%) of the 12 patients with evaluable biopsy specimens, septal panniculitis was found. Squamous syringometaplasia and mucin deposits were also detected. Treatment with high doses of prednisone and azathioprine helped in 8 of 9 patients. In 12 patients, sclerosis disappeared after 487 days. CONCLUSIONS: Leopard-skin eruption, follicular involvement, ripply skin, and lichen sclerosus lesions have been described poorly or not at all in sclerodermatous graft-vs-host disease. The presence of lichen sclerosus, morphea, septal fibrosis, and fasciitis suggests that the sclerosis can start at and affect any level of the skin. Treatment with prednisone and azathioprine seems to halt the process. Most patients have a good prognosis with treatment. Although most lesions disappear, small areas of fibrosis may remain that do not produce any physical or functional impairment.  相似文献   
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