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Objective To determine the neural substrates of biased spatial orienting in posterior cortical atrophy (PCA) by using a combined structural and functional neuroimaging approach. Background Patients with spatial neglect typically bisect horizontal long lines towards their brain lesions but the precise neural substrates of this spatial bias remain controversial and poorly explored in neurodegenerative disorders such as PCA. Methods 15 patients with PCA underwent brain MRI and single photon emission computed tomography (SPECT) and were required to bisect five 20 cm long lines, each centred on an A4 horizontal sheet. Direct correlations between average deviations on the bisection task and both (1) the degree of grey matter density, as estimated by voxel based morphometry and (2) regional cerebral blood flow, as assessed by SPECT, were performed. Results Seven patients (47%) had pathological bias on the bisection task, deviating consistently towards the non-neglected side for each of the five lines. Rightward bias (sign of left-sided neglect) was more frequent and severe than leftward bias (sign of right-sided neglect). Correlation analyses showed that rightward deviations correlated with atrophy and hypoperfusion exclusively in the right hemisphere, involving a large scale fronto-parietal network; cortical atrophy was prominent in the parieto-temporal cortex but extended to the frontal region; hypoperfusion was substantial both in the middle frontal gyrus and in the postcentral region. No correlations emerged from leftward deviations. Conclusion The results indicate that rightward bias (sign of left-sided neglect) in PCA depends on dysfunction of a large fronto-parietal network in the right hemisphere, related to both cortical atrophy and decreased cerebral perfusion.  相似文献   
94.
The "Endomedix Laparoscan" and the "Leopard" and "Panther" intraoperative ultrasounds were successfully used for the detection of unsuspected common bile duct stones during laparoscopic cholecystectomy (LC). Out of 60 patients six had common bile duct (CBD) stones and in one patient sludge has been seen. In patients with CBD stones, four small calculi have been observed in one patient, despite negative intraoperative cholangiography (IC). In an other patient a stone in the retropancreatic part of the CBD was detected. Based on preoperative findings CBD stone was unsuspected. We found that intraoperative ultrasound (IOUS) is useful for in investigating the CBD to detect unsuspected common bile duct stones. It can be used for the examination of other organs (liver, pancreas, hepatoduodenal ligament) as well. The method is easy to perform, fairly simple and informative so it can replace IC during laparoscopic cholecystectomy.  相似文献   
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Descazeaud A  Zerbib M  Flam T  Vieillefond A  Debré B  Peyromaure M 《European urology》2006,50(6):1248-52; discussion 1253
OBJECTIVES: To report our experience with biopsy-proven pT0 prostate cancer over the last 10 yr. METHODS: We retrospectively analysed a series of 1950 consecutive patients treated with radical prostatectomy (RP) for clinically localized prostate cancer between 1996 and 2005 at our institution. The patients without residual tumour on RP specimen were defined as pT0 patients. The group of pT0 patients was compared with a control group of 295 patients operated consecutively during the same period. RESULTS: Overall, 11 (0.5%) patients were classified as pT0 on pathologic examination of the RP specimen. There was no pT0 tumour in the control group. Among the pT0 patients, five characteristics were particularly frequent: T1c clinical stage (90.9%), prostate-specific antigen (PSA) or=60 g (100%). All these characteristics were present in 8 of the 11 (72.7%) pT0 patients, while they were present in only 12 of the 295 (4.1%) controls. These parameters, when combined together, had a sensitivity of 72%, a specificity of 96%, and an accuracy of 99% for the prediction of pT0 stage. With a mean follow-up of 30 months after RP, no pT0 patient had clinical or biologic evidence of prostate cancer. CONCLUSIONS: In our experience, the rate of pT0 tumours after RP is 0.5%. The combination of clinical stage, preoperative PSA, number of positive biopsy cores, Gleason score, and prostate weight could help to predict pT0 stage after RP.  相似文献   
98.

Objective

Several retrospective studies with small cohorts reported neutrophil-to-lymphocyte ratio (NLR) as a prognostic marker in upper tract urothelial carcinoma (UTUC) following radical nephroureterectomy (RNU). We aimed at validating the predictive and prognostic role of NLR in a large multi-institutional cohort.

Methods

Preoperative NLR was assessed in a multi-institutional cohort of 2477 patients with UTUC treated with RNU. Altered NLR was defined by a ratio >2.7. Logistic regression analyses were performed to assess the association between NLR and lymph node metastasis, muscle-invasive and non-organ-confined disease. The association of altered NLR with recurrence-free survival (RFS) and cancer-specific survival (CSS) was evaluated using Cox proportional hazards regression models.

Results

Altered NLR was observed in 1428 (62.8 %) patients and associated with more advanced pathological tumor stage, lymph node metastasis, lymphovascular invasion, tumor necrosis and sessile tumor architecture. In a preoperative model that included age, gender, tumor location and architecture, NLR was an independent predictive factor for the presence of lymph node metastasis, muscle-invasive and non-organ-confined disease (p < 0.001). Within a median follow-up of 40 months (IQR 20–76 months), 548 (24.1 %) patients experienced disease recurrence and 453 patients (19.9 %) died from their cancer. Compared to patients with normal NLR, those with altered NLR had worse RFS (0.003) and CSS (p = 0.002). In multivariable analyses that adjusted for the effects of standard clinicopathologic features, altered NLR did not retain an independent value. In the subgroup of patients treated with lymphadenectomy in addition to RNU, NLR was independently associated with CSS (p = 0.03).

Conclusion

In UTUC, preoperative NLR is associated with adverse clinicopathologic features and independently predicts features of biologically and clinically aggressive UTUC such as lymph node metastasis, muscle-invasive or non-organ-confined status. NLR may help better risk stratify patients with regard to lymphadenectomy and conservative therapy.
  相似文献   
99.

Purpose

The objective of this study was to evaluate the progress in performance of senior residents in diagnosing acute appendicitis.

Material and methods

Results were collected and compared of ultrasound examinations performed for suspected acute appendicitis by three senior residents and two faculty members over a six-month period in a university hospital setting. A grid with the sonographic findings was completed separately by the residents and the faculty members immediately after each examination. The duration of each examination was reported. The final ultrasound diagnosis was compared to the surgical and pathological results and to the clinical follow-up.

Results

The residents and faculty members performed 171 consecutive ultrasound examinations including 49 children with acute appendicitis and 122 with normal appendices. The accuracy of the diagnosis by the residents was 96%, and was similar to that of the faculty members (kappa = 0.90) over the six months. The duration of the resident ultrasound examinations was significantly shorter during the second three-month period (p = 0.01). No significant differences in diagnostic accuracy were demonstrated by the residents between the first and second three-month periods (p = 0.06).

Conclusions

The residents performed well when using sonography to diagnose acute appendicitis in children, and were faster during the second three-month period.

Level of evidence

I.  相似文献   
100.
Grabli D  Auré K  Roze E 《Revue neurologique》2011,167(2):123-134
Movement disorders, especially dystonia, are a frequent manifestation of neurometabolic diseases. Proper characterization and classification of movement disorders is crucial but may be challenging in this setting. The diagnostic work-up should be focused first on treatable disease. Mixed movement disorders, marked orofacial involvement and associated neurological and extra-neurological features should prompt the clinician to consider the possibility of an underlying neurometabolic disorder. The diagnostic approach is based on the abrupt, paroxysmal or insidious nature of onset of the movement disorders, the clinical picture including neurological and systemic signs and symptoms, and the presence or absence of abnormalities on the brain MRI. In addition to specific treatment for the metabolic disease, when available, symptomatic treatment of the movement disorders can be proposed, remembering that these patients are particularly vulnerability to iatrogenesis.  相似文献   
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