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31.
32.
OBJECT: Image-guided stereotactic brain biopsy is associated with transient and permanent incidences of morbidity in 9 and 4.5% of patients, respectively. The goal of this study was to perform a critical analysis of risk factors predictive of an enhanced operative risk in frame-based and frameless stereotactic brain biopsy. METHODS: The authors reviewed the clinical and neuroimaging records of 270 patients who underwent consecutive frame-based and frameless image-guided stereotactic brain biopsies. The association between preoperative variables and biopsy-related morbidity was assessed by performing a multivariate logistic regression analysis. Transient and permanent stereotactic biopsy-related morbidity was observed in 23 (9%) and 13 (5%) patients, respectively. A hematoma occurred at the biopsy site in 25 patients (9%); 10 patients (4%) were symptomatic. Diabetes mellitus (odds ratio [OR] 3.73, 95% confidence interval [CI] 1.37-10.17, p = 0.01), thalamic lesions (OR 4.06, 95% CI 1.63-10.11, p = 0.002), and basal ganglia lesions (OR 3.29, 95% CI 1.05-10.25, p = 0.04) were in'dependent risk factors for morbidity. In diabetic patients, a serum level of glucose that was greater than 200 mg/dl on the day of biopsy had a 100% positive predictive value and a glucose level lower than 200 mg/dl on the same day had a 95% negative predictive value for biopsy-related morbidity. Pontine biopsy was not a risk factor for morbidity. Only two (4%) of 45 patients who had epilepsy before the biopsy experienced seizures postoperatively. The creation of more than one needle trajectory increased the incidence of neurological deficits from 17 to 44% when associated with the treatment of deep lesions (those in the basal ganglia or thalamus; p = 0.05), but was not associated with morbidity when associated with the treatment of cortex lesions. CONCLUSIONS: Basal ganglia lesions, thalamic lesions, and patients with diabetes were independent risk factors for biopsy-associated morbidity. Hyperglycemia on the day of biopsy predicted morbidity in the diabetic population. Epilepsy did not predispose to biopsy-associated seizure. For deep-seated lesions, increasing the number of biopsy samples along an established track rather than performing a second trajectory may minimize the incidence of morbidity. Close perioperative observation of glucose levels may be warranted.  相似文献   
33.
Introduction The purpose of this study was to examine the normal pituitary gland in male subjects with ultrashort echo time (TE) pulse sequences, describe its appearance and measure its signal intensity before and after contrast enhancement. Methods Eleven male volunteers (mean age 57.1 years; range 36–81 years) were examined with a fat-suppressed ultrashort TE (= 0.08 ms) pulse sequence. The studies were repeated after the administration of intravenous gadodiamide. The MR scans were examined for gland morphology and signal intensity before and after enhancement. Endocrinological evaluation included baseline pituitary function tests and a glucagon stimulatory test to assess pituitary cortisol and growth hormone reserve. Results High signal intensity was observed in the anterior pituitary relative to the brain in nine of the 11 subjects. These regions involved the whole of the anterior pituitary in three subjects, were localised to one side in two examples and were seen inferiorly in three subjects. Signal intensities relative to the brain increased with age, with a peak around the sixth or seventh decade and decreasing thereafter. Overall, the pituitary function tests were considered to be within normal limits and did not correlate with pituitary gland signal intensity. Conclusion The anterior pituitary shows increased signal intensity in normal subjects when examined with T1-weighted ultrashort TE pulse sequences. The cause of this increased intensity is unknown, but fibrosis and iron deposition are possible candidates. The variation in signal intensity with age followed the temporal pattern of iron content observed at post mortem. No relationship with endocrine status was observed.  相似文献   
34.
35.
BACKGROUND: Assessment of centre variation in renal transplantation outcome provides an opportunity to examine differences in quality of care between centres. However, differences in outcome may represent differences in patient factors between centres and be biased by sampling variability and inadequate data ascertainment. METHODS: Differences in 12-month graft survival in 1986 primary renal transplant adult recipients from 16 centres in Australia between 1993 and 1998 were examined. Fifteen recipient and donor factors known prior to transplantation were examined to determine factors independently predictive of graft survival. Differences between centres in these factors were examined. Unadjusted and multivariable adjusted outcomes for each centre were compared to the average for all centres. Multivariable hierarchical modelling was employed to account for potential bias due to sampling variability. RESULTS: Factors predictive of reduced 12-month graft survival on multivariable analysis that were significantly different between centres were time on dialysis prior to transplantation, donor age, organ source, and number of human lymphocyte antigen mismatches. Unadjusted 12-month graft survival for all centres was 91.7% and ranged from 83.1 to 96.4%. Although two centres performed significantly lower than average, this poorer outcome was accounted for in one of these two centres after adjusting for factors shown to be independently predictive of outcome. However, multivariable hierarchical modelling failed to identify any centre as performing significantly different to average, with 12-month graft survival ranging from 89.2 to 92.2%. Outcome in patients excluded from the study due to inadequate data ascertainment was significantly worse than patients who were included. CONCLUSIONS: There was no evidence of centre variation after accounting for variation in risk factors predictive of poor outcome between centres, as well as potential bias due to sampling variability. Exclusion of patients due to inadequate data remains an important source of bias in estimating accurate outcomes. Appropriate analytical strategies and consideration of sources of bias are important for the valid identification of centres with poorer outcomes.  相似文献   
36.
Trends in kidney transplantation in Australia and New Zealand, 1993-2004   总被引:2,自引:0,他引:2  
BACKGROUND: We hypothesize that transplant outcome in Australia and New Zealand has improved despite more unfavorable transplant characteristics. Data from the Australia and New Zealand Dialysis and Transplant registry was used to examine this hypothesis. METHODS: All adult kidney-only transplants from January 1993 to December 2004 in Australia or New Zealand were followed-up until death or December 2005. Outcomes were adjusted for covariates in multivariate models, with transplant year modeled as a continuous variable. RESULTS: Altogether 6764 patients were included. There were proportionately more live donor and primary transplants, older donors and recipients, and higher recipient body mass index, waiting time, and human leukocyte antigen mismatch in recent cohorts. Death-censored graft loss decreased (adjusted hazard ratio: 0.92 [0.90-0.95] per year, P<0.001). This trend was seen at both 0-1 and 1-5 years posttransplant, and was mainly for immune-mediated graft losses. Patient survival improved only in New Zealand, and only for the first posttransplant year (adjusted odds ratio: 0.88 [0.82-0.95] per year, P=0.001). Cardiovascular deaths decreased while infection or cancer deaths were unchanged. Adjusted delayed graft function rates were unchanged. The acute rejection incidence at 6 months decreased (adjusted odds ratio: 0.88 [0.85-0.90] per year, P<0.001). One and 3-year graft function significantly improved, even after adjusting for rejection. All outcomes did not vary by expanded donor criteria status. CONCLUSIONS: Graft survival and function have improved in recent years, but long-term patient survival remains unchanged. With longer follow-up, the improvement in rejection rates and graft function may lead to further improvements in long-term graft survival and potentially better patient survival.  相似文献   
37.
There are limited techniques described in the literature on how to lower the nipple–areola complex following surgery to the breast. We present a case of successful correction of a high-riding nipple using a Z-plasty technique with an 8-year follow-up in a breast reconstruction patient. The technique described may also be applicable to cases of high-riding nipples following aesthetic breast surgery such as reduction mammaplasty.  相似文献   
38.
39.
The relationship between osteoarthritis (OA) and osteoporosis remains controversial. This study was designed to determine the association between hip and knee radiographic OA and change in total hip bone mineral density (BMD) over 2.6 years. A total of 867 population‐based randomly selected subjects (mean age 62 years, range 51 to 80 years, and 49% female) were included. Hip and knee joint space narrowing (JSN, 0 to 3) and osteophytes (0 to 3) in both lower limbs was assessed using Altman's atlas. Total hip BMD was measured by dual‐energy X‐ray absorptiometry (DXA). We found that radiographic OA (score of JSN or osteophytes > 0) was common in this sample (hip 45%, knee 68%). In multivariable analyses, percentage change in total hip BMD per year was predicted by right and left hip axial JSN (β = –0.25% and –0.29% per grade, respectively, both p < .05), right hip superior femoral osteophytes (grades 2 and 3 versus 0: β = –1.60, p < .05), combined right and left knee tibiofemoral JSN (β = –0.06 per grade from grades 0 to 12, p < .05), and osteophytes (β = –0.06 per grade from grades 0 to 14, p < .05) independent of each other and joint pain. In conclusion, older subjects with radiographic hip and knee OA have higher total hip bone loss over 2.6 years regardless of symptoms, suggesting that consideration should be given to the monitoring of bone mass in these subjects. © 2010 American Society for Bone and Mineral Research.  相似文献   
40.

Context

Controversy remains over whether adrenalectomy and lymph node dissection (LND) should be performed concomitantly with radical nephrectomy (RN) for locally advanced renal cell carcinoma (RCC) cT3–T4N0M0.

Objective

To systematically review all relevant literature comparing oncologic, perioperative, and quality-of-life (QoL) outcomes for locally advanced RCC managed with RN with or without concomitant adrenalectomy or LND.

Evidence acquisition

Relevant databases were searched up to August 2012. Randomised controlled trials (RCTs) and comparative studies were included. Outcome measures were overall survival, QoL, and perioperative adverse effects. Risks of bias (RoB) were assessed using Cochrane RoB tools. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach.

Evidence synthesis

A total of 3658 abstracts and 252 full-text articles were screened. Eight studies met the inclusion criteria: six LNDs (one RCT and five nonrandomised studies [NRSs]) and two adrenalectomies (two NRSs). RoB was high across the evidence base, and the quality of evidence from outcomes ranged from moderate to very low. Meta-analyses were not undertaken because of diverse study designs and data heterogeneity. There was no significant difference in survival between the groups, even though 5-yr overall survival appears better for the RN plus LND group compared with the no-LND group in one randomised study. There was no evidence of a difference in adverse events between the RN plus LND and no-LND groups. No studies reported QoL outcomes. There was no evidence of an oncologic difference between the RN with adrenalectomy and RN without adrenalectomy groups. No studies reported adverse events or QoL outcomes.

Conclusions

There is insufficient evidence to draw any conclusions on oncologic outcomes for patients having concomitant LND or ipsilateral adrenalectomy compared with patients having RN alone for cT3–T4N0M0 RCC. The quality of evidence is generally low and the results potentially biased. Further research in adequately powered trials is needed to answer these questions.  相似文献   
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