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排序方式: 共有1011条查询结果,搜索用时 15 毫秒
101.
We measured brain activities with a whole head magnetoencephalograph (MEG) to investigate the influence of a background odor on alphabetical encoding of words in 20 healthy volunteers (10 females). Odor stimulation and control air stimulation were both accomplished with a computer-controlled olfactometer by providing permanent stimulation conditions. Behavioral data revealed significantly prolonged reaction times in men under the influence of phenylethyl alcohol (PEA) compared to the control condition. Women did not show a change in reaction time during stimulation with PEA. A comparison of men and women revealed significantly shorter reaction times in women for both the odor conditions, as well as for the control condition. Analysis of performance accuracy showed no significant differences between the odor and the control condition within and across gender. Analysis of grand averaged, event-related fields and localization of the underlying equivalent current dipoles revealed higher dipole strength in the odor, compared to the control condition in the right hemisphere, over the temporo-parietal brain areas, in the time range between 200 and 500 ms after word-onset only in male subjects. Within this time range, the gender-specific effect is interpreted to reflect odor-related modulation of word processing. The findings suggest gender-specific processing strategies in the present task with implications for differences in hemispheric laterality.  相似文献   
102.

OBJECTIVE

Prostate cancer is still the most frequent noncutaneous male malignancy and is the second most common cause of cancer death. Genetic factors have been extensively studied in different countries. In addition, numerous genome–wide association studies have been performed in developed countries. Genetic tests will be applied in the near future for diagnosis, therapeutic, and prognostic significance. Therefore, we reviewed the association of several important pathways and genes with critical functions in prostate cancer development or progression.

MATERIALS AND METHODS

We performed a PubMed® search using several key words such as prostate cancer, names of important genes with critical function, and polymorphisms. Then, we reviewed retrieved articles as well as relevant articles from 1997 to 2009.

RESULTS

There are conflicting results of studies on some gene polymorphisms in association with prostate cancer. Most of the inconsistent results have been reported in studies investigating the vitamin D receptor gene polymorphism in association with prostate cancer. Genes related to angiogenesis and cell adhesion genes are more promising. Following results of future studies, the use of antibodies blocking over‐expressed genes or proteins may be supported in patients with prostate cancer.

CONCLUSIONS

The difference between the results of studies on gene polymorphisms in prostate cancer may be explained partly by ethnic differences, limited sample size, and other risk or protective factors modifying these effects. Genome‐wide studies are currently performed in developed countries and extensive use of this type of analysis may merit consideration in other countries. Furthermore, future studies are needed to further investigate environmental and diet factors interactions with genetic factors.  相似文献   
103.

OBJECTIVE

To analyse the morphological appearance of horseshoe kidneys (HKs) and crossed fused ectopia (CFE) and to assess the frequency and clinical significance of associated anomalies and diseases.

PATIENTS AND METHODS

The findings and images of 209 patients with fused kidneys (FKs) were reviewed; in all, 244 scans from computed tomography (CT), 233 ultrasonograms and 89 micturition cysto‐urethrograms, urograms, magnetic resonance images and angiograms were taken.

RESULTS

HKs (found in one of 474 abdominal CT scans) and CFEs (found in one of 3078 CT scans) showed a high variability of vasculature that could not be classified. However, some generalized conclusions were possible about the renal vasculature (430 arteries in 103 kidneys). Variants of the most cephalad artery of both sides were rare. The second artery on the right had a pre‐caval course. The origins of vessels located further caudal were more ventral. CFEs were anatomically different from HKs with respect to lower position, greater axial rotation, smaller pelvic width, more caudal origin, and fewer vessels, but not in accompanying anomalies. Severe anomalies or malformations were found in 23% of patients, with half of them in the urogenital system. Malformations were found considerably more often in children than in adults. There was no increased incidence of diseases such as stones or inflammation of the renal pelvis.

CONCLUSION

Concomitant anomalies and diseases were equally frequent for HK and CFE, but less frequent than generally assumed. Individual cases of complex anatomical situations require special examination strategies, and CT appears to be the most reliable imaging method.  相似文献   
104.
OBJECTIVES: To review published data on the perioperative management of antirheumatic treatment and perioperative outcome in patients with rheumatoid arthritis (RA). METHODS: The review is based on a MEDLINE (PubMed) search of the English-language literature from 1965 to 2005, using the index keywords "rheumatoid arthritis" and "surgery". As co-indexing terms the different disease-modifying antirheumatic drugs (DMARDs) as well as nonsteroidal anti-inflammatory drugs (NSAIDs) and "glucocorticoids" were used. In addition, citations from retrieved articles were scanned for additional references. Furthermore, because the number of published articles is so limited, relevant abstracts presented at congresses were included in the analysis. RESULTS: Continuation of methotrexate (MTX) appears to be safe in the perioperative period. Only a limited number of studies address the use of leflunomide and the results are conflicting. Because of the very long drug half-life, its discontinuation would need to be of long duration and is probably not necessary. Data on hydroxychloroquine do not show increased risks of infection. Regarding sulfasalazine, there are no studies from which definite answers could be drawn on whether it should be withheld perioperatively. Preliminary data show that the risk of infections during treatment with TNF-blocking agents may be lower than initially expected. The only available recommendation (Club Rhumatismes et Inflammation, CRI) suggests discontinuing the drugs before surgery for several weeks, depending on the risk of infection and the drug used. They should not be restarted until wound healing is complete. To avoid the antiplatelet effect during surgery, NSAIDs other than aspirin should be withheld for a duration of 4 to 5 times the drug half-life. Patients with chronic glucocorticoid therapy and suppressed hypothalamic-pituitary-adrenal (HPA) axis need perioperative supplementation. CONCLUSIONS: While continuation of MTX likely is safe, data on other DMARDs are sparse. In particular, more data on the perioperative use of the biologic agents are needed.  相似文献   
105.
106.
107.

Purpose

Management of long gap esophageal atresia poses challenges. The surgical techniques for esophageal replacement are associated with complications and high morbidity. The aim of this study was to develop protocols to obtain single layer sheets of esophageal epithelial cells (EECs) and to investigate their survival on collagen scaffolds.

Methods

Esophageal epithelial cells were sourced from adult Sprague-Dawley rats. Briefly, the esophagus was treated with dispase to separate the epithelial layer and further trypsined to obtained EEC. The esophageal epithelial cells were cultured in vitro and seeded on to new generation of 3-dimensional collagen scaffolds.

Results

Esophageal epithelial cells organized after 48 hours in culture and formed clusters after 72 to 96 hours. Organization of the EEC was completed after 7 days in culture and characteristic sheets of EEC with the histologic morphology of mature esophageal epithelium were obtained after 14 days of culture. Immunohistochemistry demonstrated pure EEC culture using cytokeratin (CK-14) markers. The esophageal epithelial cells transferred on to collagen polymers demonstrated excellent viability after 8 weeks of in vitro culture.

Conclusion

Successful protocols for EEC isolation and proliferation have been established. The engineering of sheets of EEC and the viability of EEC on collagen scaffolds for 8 weeks in vitro, which are prerequisites for esophagus tissue engineering, was demonstrated.  相似文献   
108.
Breast-conserving therapy for centrally located breast cancer   总被引:2,自引:0,他引:2  
OBJECTIVE: To analyze whether breast-conserving therapy (BCT) may be an oncologically safe approach and result in a good cosmesis in patients with centrally located breast cancer (CLBC). SUMMARY BACKGROUND DATA: Only underpowered, retrospective, single-arm studies have suggested that oncoplastic BCT for CLBC may be oncologically safe and may result in a good cosmesis. METHODS: The authors retrospectively analyzed the overall and recurrence-free survival in 1485 patients with breast cancer undergoing BCT comparing CLBC with non-CLBC. Moreover, the authors described 4 different oncoplastic techniques for BCT in patients with CLBC and compared the cosmetic results with simple lumpectomy according to a recently elaborated objective cosmetic evaluation system, the Breast Symmetry Index. RESULTS: Kaplan-Meier curves show no significant difference in a 5-year overall, local, or distant recurrence-free survival between patients with CLBC and non-CLBC after BCT (94% vs. 96%; 100% vs. 98%; 92% vs. 90%; median follow-up, 35.3 months). The cosmetic outcome after oncoplastic BCT compared with simple lumpectomy differed significantly (Breast Symmetry Index: 22 +/- 6%d vs. 44 +/- 12%d; P < 0.05). CONCLUSIONS: The results demonstrate that BCT for CLBC is oncologically safe and that oncoplastic techniques improve cosmesis.  相似文献   
109.
Over the years, multiple articles on Artemisinin-based Combination Therapies (ACTs) were published, highlighting the relative advantages or drawbacks of these combinations. Many studies were comparative. Because none of the studies compare all combinations and methodology varies between studies, there is no homogeneity. A multi-treatment Bayesian random-effects meta-analysis was designed to assess the relative effect of each combination therapy to artesunate + sulfadoxine-pyrimethamine (4 mg/kg/day for 3 days). By far the most attractive result for the variable adequate clinical and parasitological response at day 28 PCR corrected is given by the combination artemether-lumefantrine. Annual follow-up on the data published is intended to reveal the changes in the relative drug efficacy values of ACTs.  相似文献   
110.
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