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One thousand biopsy specimens obtained from 10 sites in the stomachs of 50 patients were examined for the presence of active chronic gastritis and Campylobacter pylori. All 32 patients with active chronic gastritis at 234 out of 320 sites were positive for C pylori: 227 showed colonisation with C pylori by the Warthin-Starry stain; and 222 were positive by culture. C pylori was not found in 18 patients with inactive chronic gastritis or histologically normal mucosa. The area of C pylori colonisation was larger than the area of active chronic gastritis in 289 positive specimens on culture and 261 on staining, respectively, suggesting that C pylori colonisation may precede the development of active chronic gastritis. It is concluded that patchy distribution of active chronic gastritis and C pylori colonisation must be considered, particularly in serology or breath test studies where the histological examination serves as a reference. Furthermore, it may have important implications for the follow up of patients after antibacterial treatment. The topographic and specific association of C pylori and active chronic gastritis provides further evidence for the pathogenic role of C pylori in active chronic gastritis.  相似文献   
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AIMS--To evaluate further the relation between gastric malignant lymphoma of the mucosa associated lymphoid tissue (MALT) and Helicobacter pylori. METHODS--One hundred and sixty two surgical specimens of MALT lymphoma were retrospectively investigated to determine tumour type and inflammatory patterns. In 121 cases biopsy specimens obtained before surgery were available and stained with haematoxylin and eosin, periodic acid Schiff, Giemsa and Warthin-Starry stains. RESULTS--Residual lymphoid follicles were found less often in high grade malignant than in low grade malignant MALT lymphomas. Chronic active gastritis was shown within the mucosa at some distance from the tumours in 143 of 146 specimens. In all the cases for which biopsy specimens could be evaluated, colonisation of the mucosa by H pylori had occurred. Lymphoid follicles and lymphoid aggregates were detected in 82.7% of the antral, and in 85% of the body mucosa specimens. CONCLUSIONS--These data support the hypothesis that H pylori has an important role in the development of MALT lymphomas. Furthermore, the chronic inflammation preceding malignant transformation might enhance the probability of malignant transformation via chronic stimulation of the lymphoid tissue. This might in part indicate why MALT lymphomas occur most often in the stomach.  相似文献   
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Macrolide-resistant Helicobacter (H.) pylori represent an increasing therapeutic problem. Macrolide resistance is usually determined phenotypically in vitro with methods such as E-test or agar dilution test. A prerequisite for those tests, however, is bacterial culture that is not routinely set up in the course of gastroscopy. In contrast, formalin-fixed, paraffin-embedded biopsies are regularly available from patients who have undergone gastroscopy. In such biopsies macrolide-resistant H. pylori can be detected by the genotype-based technique of fluorescence in situ hybridization (FISH). Experience gained by this new method, however, is still extremely limited, especially in formalin-fixed tissue. Therefore, we retrospectively investigated formalin-fixed, paraffin-embedded biopsy specimens by FISH in 104 patients suffering from therapy-resistant H. pylori gastritis. To test the accuracy of FISH, we initially examined specimens from 53 patients for whom results of the E-test were available. Next we analyzed biopsies from another 51 patients that had been selected since phenotypical resistance testing had failed despite documented culturing attempts. In all 104 patients, H. pylori was detected by FISH and could thus be investigated for macrolide resistance. Overall, macrolide-resistant bacteria were found in 71 patients (68.3%). In 49 of 53 patients (92.4%), FISH and E-test returned identical results (no significant discordance according to McNemar's chi(2)-test). Taken together, our study demonstrates that FISH is a highly sensitive and reliable method for detecting macrolide-resistant H. pylori in formalin-fixed, paraffin-embedded biopsy specimens, which represents the routine method of processing tissue obtained upon gastroscopy.  相似文献   
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The results of several retrospective studies allow us to conclude that the detection of fundic gland polyps (Elster's cysts) is associated with an increased incidence of colorectal tumors. In this survey, we present the results of a prospective study investigating such a possible relationship. A total of 144 patients were investigated, of whom 80 had fundic gland polyps of the gastric corpus mucosa. Sixty-four of these patients underwent a colonoscopy, whereas the other 64 patients belonged to a sex- and age-matched control group with no fundic gland polyps. In the group with known fundic gland polyps, colorectal neoplasias were found in 29 (45.3%) patients. Eight of these patients had (12.5%) adenocarcinomas, 3 (4.7%) had high-grade intraepithelial neoplasia, and 18 (28.1%) had tubular adenomas. In one patient, a synchronous carcinoma of the rectum and the colon was detected. In comparison, 6 patients of the control group (9.3%) developed tubular adenomas and 9 (14.1%) had hyperplastic polyps of the colonic and rectal mucosa. Our results suggest that it is necessary to conduct a careful diagnostic work-up of the colon in patients with gastric fundic gland polyps.  相似文献   
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In a 46-year-old man, a pedunculated rectal polyp measuring 3.0×3.0×2.0 cm was diagnosed histologically as a pyloric gland-type adenoma arising in heterotopic gastric corpus mucosa. The luminal site was covered by glands of the gastric foveolar type, displaying focal marked proliferation interpreted as low-grade intraepithelial neoplasia. A bidirectional gastric differentiation was found: most lower glandular structures showed positivity for the deep gastric mucin core protein Muc 6 and superficial positivity for gastric foveolar epithelium mucin core protein Muc 5AC. Pyloric gland adenoma has so far been described in one larger series only and a few case reports of the stomach, gallbladder, pancreatic duct and within heterotopic gastric corpus mucosa of the duodenal bulb. The present case report is the first case of a pyloric gland-type adenoma within a gastric corpus heterotopia of the rectal mucosa.  相似文献   
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BACKGROUND: Novel technology based on laser optogalvanic spectroscopy called the LARA (Laser Assisted Ratio Analyser) system was developed to measure 12C/13C ratios in breath samples using stable 13C isotopes, to detect Helicobacter pylori infection. AIM: To determine the sensitivity and specificity of the 13C-LARA-urea breath test in the detection of H. pylori infection in a prospective European multicentre trial; FDA-and EMEA-approved. METHODS: Consecutive dyspeptic patients underwent diagnostic gastroscopy with biopsies for culture and histopathology, to detect H. pylori infection (gold standard). Subsequently, the LARA-urea breath test was performed using either a system without a cold trap (part I) or a system with a cold trap (part II). In both instances baseline, 30-min and 60-min breath samples were collected. The optimum cut-off level for 12C/13C ratios was determined by Receiver Operator Characteristics analysis. RESULTS: In part I, 544 out of 604 patients were evaluable (low CO2: 47; withdrawn: 13). 284 out of 544 patients (52%) were H. pylori-positive according to the gold standard. The sensitivity of the LARA-urea breath test was 95% and the specificity 94%. In part II, 257 out of 272 were evaluable (low CO2: 14; withdrawn: 1). Sensitivity and specificity were 93% and 96%, respectively. CONCLUSION: The LARA-technology represents an accurate and non-invasive testing system for the detection of H. pylori infection. Its major advantages are the use of stable 13C isotope, the high throughput of samples and the easy means of collecting, storing and transporting the samples, thus making the system convenient to both patient and clinician.  相似文献   
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