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31.
Meckel''s diverticulum is a true intestinal diverticulum that results from the failure of the vitelline duct to obliterate during the fifth week of fetal development. In about 50% cases, it contains ectopic or heterotopic tissue which can be the cause of complications. A systematic review of literature was undertaken to study the history, incidence, embryoanatomy, clinical presentation, complication and management of Meckel''s diverticulum. Although Meckel''s diverticulum is the most common congenital abnormality of the gastrointestinal tract, it is often difficult to diagnose. It may remain asymptomatic or it may mimic disorders such as Crohn''s disease, appendicitis and peptic ulcer disease.  相似文献   
32.
Pathology-based cancer data is a high quality reflection of the patterns of cancer in the population it represents, provided the demographic details of the patients are carefully recorded. Relative frequency data is neither a replacement for population-based data nor a suggested alternative; it simply enhances the quality of population data and in very large data sets reflects the cancer patterns observed in the representative populations. Aware of the standard shortfalls of pathology-based data, the department of pathology, The Aga Khan University Hospital (AKUH) standardized its data, representing 53.4% of the cancer data of Karachi Division (Pakistan) and also reflecting the cancer pattern of other provinces of Pakistan. This data was compared with 4 different population and institutional-based data sets. The findings substantiate the observation that despite the problems of interpretation of data from pathology laboratories, they are an invaluable source of information on cancer patterns in much of the world where incidence data are unavailable . If developing countries, unable to organize National Population- Based Registry should as an alternate develop National Pathology-based Registers a well targeted and monitored, a Cancer Control Program would be possible. A good quality, large-scale pathology data with demographic details of the patient recorded can also be extended to give coverage to the population.  相似文献   
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34.
Bone marrow transplantation (BMT) is a successful and recognised treatment option for patients with a number of haematological and non-haematological malignant and non-malignant conditions. Pulmonary complications both infectious and non-infectious are common after BMT. Multiple factors are thought to contribute to pulmonary complications, including the type and duration of immunological defects produced by the underlying disease and treatment, the development of graft-versus-host disease (GVHD), and the conditioning regimens employed. These complications are classified as early or late, depending on whether they occur before or after 100 days from transplantation. Early non-infectious pulmonary complications typically include pulmonary oedema, upper airway complications, diffuse alveolar haemorrhage, cytolytic thrombi, and pleural effusion. Bronchiolitis obliterans, veno-occlusive disease, and secondary malignancies occur late after BMT. Idiopathic pneumonia syndrome, GVHD, and radiation induced lung injury can occur in early or late period after BMT.  相似文献   
35.
To evaluate the role of ras activation and human papillomavirus (HPV) infection in laryngeal carcinoma, we analyzed tumor DNA from 43 cases, including 25 primary laryngeal tumors, 12 lymph-node and one skin metastases, and 5 recurrent laryngeal carcinomas. Thirteen normal laryngeal tissues and 7 benign laryngeal nodule biopsy specimens along with normal tissue surrounding laryngeal carcinoma in 2 cases were also included. The polymerase-chain-reaction technique was used to amplify DNA fragments containing codon 12 and 61 of H-, K- and N-ras, also HPV 16, 18 and 33 DNA, subsequently hybridized with sequence-specific oligonucleotides. DNA samples from 22 patients with laryngeal carcinoma revealed ras mutations (18 in N-ras codon 12, 6 in H-ras codon 61, and 3 in K-ras codon 61). Likewise, HPV DNA was found in 16 cases (HPV 16, 18 and 33 in 3 cases, 14 cases and 1 case respectively). ras mutations were significantly higher in metastatic tumors (10 of 13 cases) than in primary (11 of 25 cases) and recurrent laryngeal carcinomas (1 of 5 cases). HPV DNA was detected in 60% of recurrent, 44% of primary and 15% of metastatic tumors. Only 2 of the 13 normal laryngeal tissues and 1 out of 7 laryngeal nodule specimens were found to contain HPV DNA. These results suggest that ras activation, especially in N-ras codon 12.1 (GGT → AGT) and HPV infection are 2 important factors in (multistage) laryngeal carcinogenesis. The ras mutation may be associated with metastatic ability of the tumor.  相似文献   
36.
Summary— This paper is a compendium of exact and asymptotic formulas and tables for calculating the sample size in a clinical trial for a matched-pair design involving a dichotomous outcome. Formulas for calculating power given the sample size are also given.  相似文献   
37.
A 16-month-old infant with hepatic fibrosis, cholestasis, and chronic jaundice had signs of vitamin E deficiency, including mild acanthocytosis, thrombocytosis, increased peroxide haemolysis, and absent serum vitamin E. Abormal prothrombin consumption and platelet restocetin aggregation suggested the presence of defective platelet function, and correction studies indicated that this was due to a plasma defect. The abnormality was corrected by treatment with vitamin E, and the findings suggest a possible role of this vitamin in platelet reactions.  相似文献   
38.
OBJECTIVE: The prostate specific antigen (PSA) era has been associated with a grade migration towards moderately-differentiated (Gleason 5-7) prostate cancer. We investigated whether changes in interpretation of the Gleason system could be a contributing factor by reviewing the Gleason scores for prostate cancer in our region. PATIENTS AND METHODS: Records of patients with prostate cancer assigned a Gleason score between 1991-2001 were retrospectively reviewed. We analysed trends in Gleason score, method of diagnosis and age at diagnosis. Following this, 50 cases from the dataset were randomly selected (stratified to contain half Gleason 2-4 reports) and reviewed in a blinded manner by an uropathologist and given a new Gleason score. RESULTS: 2737 patients were diagnosed and given a Gleason score; 1484 by prostate biopsy (PB) and 1172 by transurethral resection of prostate (TURP). 273 radical prostatectomy (RP) specimens were received, although the results of pre-operative biopsies were available in only 192 of these patients. Over time, there was an increase in the proportion of patients with Gleason 5-7, and a significant decrease in reporting of Gleason 2-4 cancer (r2 = 0.81, p < 0.0001). In 1991, 24% of cancers were Gleason 2-4; in 2001 this had decreased to 2.4%. TURP was associated with more Gleason 2-4 reports (23%) compared with PB (13.2%) and RP (9.2%). On blinded review, all Gleason 2-4 reports were upgraded to Gleason 5-7 cancer (p < 0.001). CONCLUSION: Over time, the proportion of Gleason 2-4 prostate cancer reported has significantly decreased. Our study suggests that a change in practice by the pathologist is a significant factor in this grade migration.  相似文献   
39.
BACKGROUND AND PURPOSE: Stone size forms the basis of management pathways in patients with urolithiasis. We carried out a questionnaire-based audit to find out how stone size is routinely measured by radiologists in the UK. MATERIALS AND METHODS: A series of 831 anonymous questionnaires concerning how stone size is assessed using four imaging modalities--plain abdominal radiograph (KUB film), intravenous urogram (IVU), ultrasound, and CT--were sent to 277 radiology departments. Following the survey, a substudy at our institution compared urologists (N = 10) and radiologists (N = 5) in estimating the size of a large (26-mm) and small (11- mm) calculus on KUB films. RESULTS: Of the questionnaires, 425 were returned, and 421 were analyzed. Of these, 85% were from consultants, 14% from trainees/middle grades, and 1% "unspecified." In total, 92% of the respondents were radiologists (10% uroradiologists) and 8% urologists. Estimation of stone size ("guestimation") from KUB films and IVUs was used by 40% and 36% of radiologists, respectively, whereas graded rulers were used by 57% and 59%, respectively. For ultrasound scans and CT, electronic measurement was the favored method (81% and 73%), but guestimation was still used by 10% and 15%, respectively. When assessing the KUB films and IVU, 59% and 61% of urologists, respectively, also used guestimation. The substudy revealed a significant difference among radiologists in the accuracy of size estimation for the 11-mm stone (mean estimated size 9.6 mm; P = 0.02, one-sample t-test). CONCLUSION: A large proportion of radiologists use guestimation for assessing stone size on KUB films and IVU. Even when electronic measuring aids were available for CT and ultrasonography, guestimates remained prevalent. Our substudy showed that radiologists significantly underestimated the smaller stone.  相似文献   
40.
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