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81.
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PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM.  相似文献   
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Background: How breast cancer surgery affects social adjustment among Chinese women is unknown, as are factors predicting such adjustment. Methods: 405 Chinese women receiving surgery for localized breast cancer completed Social Adjustment Scales (Ch‐SAS) at 1‐, 4‐ and 8‐months post‐operatively. Subscale scores were regressed on baseline (days 3–12 post‐operatively) measures of treatment decision‐making difficulty (TDMD), self‐efficacy (GSeS), consultation satisfaction (C‐MISS‐R), psychological (CHQ‐12) and physical distress (PD), and 1‐month follow‐up optimism (C‐LOT‐R), and disappointment (E‐OI), fully adjusted for demographic and clinical factors. Results: All Ch‐SAS subscales except appearance & sexuality changed significantly over 8‐months follow‐up: Enjoyment of social activities (F=27.38, df 2, p<0.001) and self‐image (F=3.63, df 2, p=0.027) improved slightly. Family interaction (F=26.63, df 2, p<0.001) and interaction with friends (F=3.37, df 2, p=0.035) declined slightly. Family and friends interaction subscales were predominantly predicted by high self‐efficacy and optimism, whereas self‐image and appearance & sexuality subscales were predominantly predicted by low treatment outcome disappointment, TDM difficulties, baseline psychological morbidity and high self‐efficacy. Enjoyment of social activities was predicted by low baseline psychological distress and concurrent physical symptom distress. Conclusion: High self‐efficacy and optimism predicted women who have better social relationships with friends and family. Higher self‐efficacy, low TDM difficulties, less disappointment with treatment outcome and low psychological and physical distress predicted better adjustment to self‐image and body image. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
85.
The possibility to use the colorimetric MTT assay for measuring proliferation and cell death of human peripheral blood lymphocytes (PBL) was studied. In a range from 100,000-800,000 cells/well a linear correlation between the optical signal (OD signal at 570 nm) and the cell number was found. It is necessary to incubate the cells with the MTT at least 2 hours. After stimulation by different PHA concentrations a very good correlation between [3H] thymidine incorporation and MTT assay was found. A comparison of daunomycin cytotoxicity, measurement by trypan blue exclusion and MTT assay, gave also a good correlation between both methods. It can be pronounced that the MTT assay is a suitable method to measure cell proliferation and cell death of human PBL. The assay is easy to handle, a large number of probes can be assayed in a relatively short time and no radioactivity is necessary. For the measurement of the colored product a common ELISA reader can be used.  相似文献   
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Reinig  JW; Gordon  L; Frey  D; Garrick  E; Daniel  WT  d 《Radiology》1985,156(2):505-507
The clinical assessment of a transplanted kidney is often difficult, especially in the immediate postoperative period. The biochemical parameters used to monitor renal function change slowly and can take several days to reflect the actual renal status. We have modified a technique for determining the glomerular filtration rate (GFR) from a Tc-99m DTPA renal scan and have found that it correlates with the actual GFR throughout the postoperative course. In addition, we describe a method for changing dose calibrator measurements into administered counts. This technique for determining the GFR provides a quick and accurate assessment of renal function and is useful to guide therapeutic decisions.  相似文献   
88.
Bone mass and structure at the proximal femur are important predictors of hip fracture. The aims of this study were to compare in a large sample of elderly men and women the precision of measurements of bone mass and structure at multiple sites at the proximal femur, to examine their interrelationships, to establish their relationships with age and body size, and to examine criteria for defining geometric and architectural variables in bone structure. Women (n= 336) and men (n= 141) over the age of 60 years were studied cross-sectionally. Bone mineral density (BMD) and content (BMC) at the proximal femur were measured in duplicate by dual-energy X-ray absorptiometry (DXA). Shaft and total upper femur (hip) sites in addition to femoral neck, Ward's triangle and trochanter were measured. Structural variables, measured from radiographs and from DXA images, including cortical thickness at calcar femorale, lateral cortex and mid-femur, width of the femur and medulla, Singh grade, hip and femoral axis length, femoral head and neck width and the center of mass of the femoral neck. BMD and BMC had high reproducibility and there were significant differences in reproducibility across sites. Among sites, total upper femur and shaft had the highest reproducibility. Duplicate measurements substantially improved reliability of the measurement and are recommended when the value is close to a diagnostic level or when it will be used to establish rates of change. Reproducibility of structural variables was also high except for the lateral cortex, center of mass and Singh grade. Variance due to measurement error did not change with either age or gender. Women were significantly different from men, after controlling for differences in body size, in all variables except Singh grade and medulla width. BMD and BMC were negatively related to age and positively to body size. Structural variables examined in relation to age and body size fell into two categories. The first comprised variables that were not age-related but were body-size-related, suggesting that they could be classified as geometric variables. The second comprised variables that were both body-size-related and age-related, suggesting that they could be classified as architectural variables. Using these criteria, calcar and lateral cortex were architectural variables, whereas shaft width, hip and femoral axis length, femoral head and neck width, and center of mass were geometric in both men and women. In women, shaft cortex width and medulla width were age-related, whereas in men they were not. Singh grade showed no consistent pattern with age or body size in women and men. Received: 7 January 1997 / Accepted: 7 November 1997  相似文献   
89.
A 64-year-old man with history of ischaemic heart disease and coronary artery bypass graft surgery, but no history of peptic ulcer or liver disease, presented with retrosternal pain and coffee-ground vomitus. Endoscopy revealed a long column of bluish discolouration with normal mucosa interpreted as a grade IV oesophageal varix. Computed tomography showed a non-enhancing low-density submucosal columnar lesion in the mid- and lower oesophagus consistent with a submucosal haematoma. This resolved on follow-up at 10 days. The magnetic resonance features of intermediate signal intensity on T1 -weighted images and hyperintense signal on T2-weighted images of this lesion are also highlighted.  相似文献   
90.
Practicing thoracic surgeons were randomly surveyed to evaluate how computed tomography (CT) has influenced the preoperative evaluation of bronchogenic carcinoma. Thirty-six percent of the 529 respondents routinely requested CT and 62% did so selectively. Approximately 40% indicated that CT provided useful information in most cases. Nearly all surgeons (98.7%) do not rely on the identification of enlarged lymph nodes with CT to spare the patient surgical staging; however, 77.5% are influenced by CT results in their staging procedures. Fifty-seven percent reported that a negative CT study eliminates surgical staging entirely unless the patient has a "coin lesion," in which case 75% are willing to proceed directly to thoracotomy. For surgeons who use CT selectively, an abnormal mediastinal contour on the radiograph was the most frequent radiologic abnormality to prompt CT (85%). Thirty-seven percent are influenced by tumor histology in their decision to request CT. There was little difference in the pattern of CT use between university and community hospital surgeons.  相似文献   
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