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Objectives: The epidemiology of lower gastrointestinal bleeding (LGIB) in Western populations has been reported; however, there are scant Asian reports. The aim of the present study was to determine the etiology of LGIB in a Chinese population by reporting a retrospective case series and a systematic analysis of Chinese literature. Methods: A large colonoscopy database in a tertiary endoscopic center was searched to identify all patients with the indication of LGIB. The data, including patients' sex, age, endoscopic and pathological findings, were collected and analyzed. A comprehensive database search of the Chinese literature was carried out to obtain all relevant studies. Results: In our series, a total of 720 patients with LGIB were included. There were 425 males and 295 females with a median age of 50 years, the most common etiologies of LGIB were inflammatory bowel disease (IBD; 30.2%), polyps (23.4%) and cancer (10.7%). In 30.2% of all the patients, no obvious causes were identified. A systematic analysis of Chinese literature found an additional 160 studies providing relevant data in 53 951 patients. Overall, colorectal cancer (24.4%), colorectal polyps (24.1%), colitis (16.8%), anorectal disease (9.8%) and IBD (9.5%) were the most common etiologies of LGIB. The main etiologies were different between adults, the elderly and children. Conclusion: The study shows colorectal cancer, colorectal polyps, colitis, anorectal disease and IBD were the most common etiologies of LGIB in the Chinese adult and elderly population, whereas colorectal polyps, chronic colitis and intussusception were the main causes of LGIB in Chinese children. Whereas diverticulum, the most common cause of LGIB in Western populations, is uncommon in China. 相似文献
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Eduardo Rodrigues‐Pinto Joel Ferreira‐Silva Guilherme Macedo Douglas K. Rex 《Digestive endoscopy》2019,31(5):583-587
Cecal intubation is a critical aspect of effective, complete colonoscopy. Difficult colonoscopy is most often considered as one in which it is challenging or impossible to reach the cecum. It may be a common occurrence due to patient and/or endoscopist factors. Incomplete colonoscopies should be avoided, since patients in this context present an important prevalence of lesions that escape examination. The approach to successful cecal intubation should depend on characterization of the problem as redundant colon or difficult sigmoid colon. Most patients with a prior incomplete colonoscopy can be colonoscoped successfully, if careful attention is paid to technique, using a variety of scopes, colonoscopy methods and additional equipment. Sufficient time should be allotted to make the attempt. 相似文献
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Astrid T. Stormorken Neal Clark Eli Grindedal Lovise Mæhle 《Scandinavian journal of gastroenterology》2013,48(5):611-617
Objective. In recent years persons at risk for colorectal cancers (CRC) have been subjected to follow-up with colonoscopy in many centres. There is, however, limited knowledge about the effect of such interventions. The objective of this study was to report the results of our observations during the past 15 years. Material and methods. Healthy persons were included in the study according to their family history of CRCs, and prospectively followed with colonoscopies. Results. Altogether, 1133 individuals were included and observed for a total of 3474 follow-up years from the first to the last colonoscopy initiated by our activity. Mismatch repair (MMR) mutations were detected in 6.5% of cases. A total of 1383 polyps were removed, 72% were less than 5 mm in diameter. Findings were scored as hyperplastic polyps (n=887), adenomas with mild to moderate dysplasia (n=460), adenomas with high-grade dysplasia (n=30) and cancers (n=6). Two cancers were observed after the first colonoscopy, compared with 2.6 expected by chance and more than 20 expected under the hypothesis of predominant inherited diseases in the families. Observed annual incidence rates for adenomas were similar in all groups, while in the mutation carriers there was a higher frequency of progression to severe dysplasia or infiltrating cancer. Conclusions. A simple explanation for the combined findings may be that all selected families had a similar tendency to produce adenomas, while mutation carriers more frequently demonstrated dysplasia/cancer in the adenomas. The low annual incidence rates for CRC indicated that the removal of adenomas may have prevented cancers. 相似文献
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《Expert Review of Gastroenterology & Hepatology》2013,7(3):211-213
Existing and emerging colorectal screening tests can be assessed in terms of the key categories of diagnostic performance, procedural risks, patient acceptability, and cost-effectiveness. To push a new screening test to acceptance, it need not outperform existing strategies in all of these criteria. Rather, a relative advantage in one criterion combined with acceptable performance in the others may be considered adequate. For computed tomographic colonography (CTC), a strong case can be made that this test meets or exceeds optical colonoscopy, the current screening standard, in all of these categories. Published data, including our own experience with CTC screening, will be reviewed to support this claim. Reasons why CTC has not yet achieved its full potential as a valuable screening test for colorectal cancer prevention will also be considered. 相似文献
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《Minimally invasive therapy & allied technologies》2013,22(1):25-30
A method of fibre-optic colonoscopy with simultaneous high resolution MRI has been developed to obtain cross-sectional information of the intramural and extramural extent of lesions, for diagnostic and therapeutic purposes. An MR-compatible colonoscope with receiver coil was designed, developed and used in ex vivo studies to scan a section of large bowel in transverse and longitudinal planes with T1 and T2 weighted spin-echo sequences. In vivo five patients were followed-up after excision of large bowel cancer. The patients were three men and two women aged 50-77 years, (mean 65.6 years) who were studied on a 0.5 T scanner (Picker Asset, OH, USA). The coil and colonoscope were inserted into the rectum. After routine visual inspection of the colon, T1 weighted spin-echo images and radio-frequency spoiled gradient-echo images of the bowel wall were obtained. Ex vivo: three layers of bowel wall were identified: an intermediate to high signal-intense mucosa, a high signal intensity layer on T1 weighting which corresponded to the submucosa, and a low signal intensity muscularis propria. In vivo: On T1 weighted images three layers could be identified that corresponded to the layers seen on the ex vivo imaging. This pilot study demonstrates that MR colonoscopy is feasible and allows delineation of bowel wall structure, thus providing a useful adjunct to conventional colonscopy. 相似文献