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1.
About 85% of the population of two Somali communities harboured soil-transmitted intestinal nematodes and/or protozoa. The commonest parasite (75% in the Lafoole institution and 59% in the Afgoye institution) was Trichuris trichiura. Mixed infections were common. The source of infection is contaminated fields around dwelling quarters, because of indiscriminate defaecation. One of the factors responsible for the higher incidence of hookworm in Lafoole (45%) compared with Afgoye (1.5%) may be the different soil character of the surrounding fields.  相似文献   
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以18-甲基-17β-羟基-17α-乙炔基-雌甾-4-烯-3-酮(18-甲基炔诺酮),17β-羟基-17α-乙缺基-雌甾-4-烯-3-酮(炔诺酮),17β-羟基-17α-乙炔基-雄甾-4-烯-3-酮(妊娠素)和17a-羟基孕甾-4-烯-3,20二酮(17α-羟基黄体酮)为原料,经NaBH,还原、脱水、双键转位和酯化等反应合成一系列3,5-甾二烯化合物,用1HNMR和MS证明了它们的结构。动物筛选结果表明,17β-丙酰氧基-17α-乙炔基-雌甾-3,5-二烯(IVb2有明显的抗早孕活性。中断早期妊娠的作用似与其雌激素活性有关。  相似文献   
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Bile duct calculi in patients with primary sclerosing cholangitis   总被引:1,自引:0,他引:1  
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The authors present a retrospective study concerning 135 cases of untreated synchronous metastases from colorectal cancer. The median survival is 5.5 months and the natural history is depending on the percentage of liver replacement, on the "performance status" of each patient and on the stage of primary tumors classified according to Dukes. The seric levels of Alkaline Phosphatase and CEA are other useful prognostic factors. The age of patients and systemic chemotherapy (5-Fluorouracil) are not able to influence the evolution of the disease. At last different techniques, both curative and palliative, used in the current treatment of liver metastases from colorectal cancer are discussed and the reported survival improvements reaching with these forms of treatment are compared to the natural history of the disease.  相似文献   
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In an attempt to clarify how cells integrate the signals provided by multiple chemokines expressed during inflammation, we have uncovered a novel mechanism regulating leukocyte trafficking. Our data indicate that the concomitant exposure to CCR4 agonists and CXCL10/IP-10 strongly enhances the chemotactic response of human T lymphocytes. This enhancement is synergistic rather than additive and occurs via CCR4 since it persists after CXCR3 blockade. Besides chemotaxis, other cellular responses are enhanced upon stimulation of CCR4-transfected cells with CCL22/MDC plus CXCL10. Several other chemokines in addition to CXCL10 were able to increase CCL22-mediated chemotaxis. The first beta-strand of the chemokine structure is highly and specifically implicated in this phenomenon, as established using synergy-inducing and non-synergy-inducing chimeric chemokines. As shown in situ for skin from atopic and allergic contact dermatitis patients, this organ becomes the ideal environment in which skin-homing CCR4(+) T lymphocytes can accumulate under the stimulus offered by CCR4 agonists, together with the synergistic chemokines that are concomitantly expressed. Overall, our results indicate that chemokine-induced synergism strengthens leukocyte recruitment towards tissues co-expressing several chemokines.  相似文献   
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Summary Accurate volume determination of the encephalic ventricles is of importance in several clinical conditions, including Alzheimer's presenile dementia, schizophrenia, and benign intracranial hypertension. Previous studies have investigated the accuracy with which magnetic resonance imaging (MRI) can be used in clinical practice to evaluate the encephalic ventricles. However, adequate evaluation of pathological conditions depends on a sufficient amount of morphometric data from normal subjects. To begin establishing this data base for normal subjects, we evaluated the MRI scans of 38 subjects found to have no apparent pathology and calculated the ventricular volume in each case by using methods previously developed in our laboratory. The results were then compared with published volumes determined from studies that used either ventricular casts or computerized tomographic scans. The average total ventricular volume for all 38 subjects was 17.4 cm3, while that for males was 16.3 cm3 and that for females was 18.0 cm3. A small but significant correlation was found between age of subject and ventricular volume, with ventricular size increasing with age.
Evaluation du volume des ventricules cérébraux à partir des images obtenues en résonance magnétique nucléaire chez 38 sujets humains
Résumé La détermination exacte du volume des ventricules cérébraux est importante en clinique comme par exemple dans la démence présénile d'Alzheimer, la schizophrénie et l'hypertension intracrânienne bénigne. Des études antérieures ont étudié la fiabilité de la résonance magnétique nucléaire en pratique clinique pour évaluer le volume des ventricules cérébraux. Toutefois une évaluation correcte dans les conditions pathologiques implique une bonne connaissance des données morphométriques du sujet normal. Pour établir ces données sur « le sujet normal », nous avons étudié les coupes obtenues en IRM chez 38 sujets apparemment indemnes de toute pathologie; nous avons calculé le volume ventriculaire dans chaque cas en utilisant des méthodes mises au point auparavant dans notre laboratoire. Les résultats ont été ensuite comparés avec ceux obtenus par d'autres études utilisant soit des moules ventriculaires, soit des coupes tomographiques computérisées. Le volume ventriculaire total moyen chez 38 sujets est de 17,4 cm3, mais il est chez les sujets masculins de 16,3 cm3 et chez les sujets de sexe féminin de 18 cm3. Une corrélation faible mais significative a été trouvée entre l'âge du sujet et le volume ventriculaire, étant entendu que la taille du ventricule augmente avec l'âge.
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INTRODUCTION: Properly oriented endoscopic biopsies allow an effective assessment of some diagnostic features in non neoplastic gastrointestinal diseases. MATERIALS AND METHODS: We used cellulose acetate millipore filters (Endofilter, Bio-Optica, Milan, Italy) in order to improve the orientation of biopsies during processing. Forty biopsies were placed on filter after endoscopic sampling whereas no orientation attempt was done for other 40 filter-free biopsies (20 from esophagus and 20 from gastric antrum in each group). Both groups were compared in terms of orientation and assessability of the following morphological features: thickness of basal layer in the esophageal squamous epithelium, length of esophageal papillae, interstitial space dilatations in the esophageal squamous epithelium and gland atrophy in the gastric antrum. Both orientation and assessability of individual morphological features were graded with a score ranging from 1 (good) to 3 (poor). The impact of this procedure on costs was analysed, both in terms of material and technical workload. RESULTS: All 20 esophageal and 20 antral biopsies on filter showed acceptable (score 1 or 2) orientation. In contrast, 14/20 filter-free esophageal and 13/20 antral biopsies showed poor (score 3) orientation (p = 0.0001 for both groups). Basal layer thickness was assessable (score 1 or 2) in 20/20 esophageal biopsies on filter vs 14/20 filter-free ones (p = 0.0001) and length of papillae in 15/20 biopsies on filter vs 4/20 filter-free ones (p = 0.0002). Interstitial space dilatation assessability was not affected by orientation procedures. Gland atrophy in the antrum was assessable (score 1 or 2) in 20/20 gastric biopsies on filter vs 8/20 filter-free ones (p = 0.0001). The use of endofilters permitted the process of numerous (up to 8 for each block) samples from different biopsy sites together and produced a significant reduction in costs (18.35 in the case of 8 biopsies from 4 different biopsy sites). CONCLUSIONS: The use of millipore filters allows orientation of biopsy samples, improves the assessment of several diagnostic features in esophageal and gastric pathology and yields a significant reduction in costs when biopsies from different sites are processed together.  相似文献   
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