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11.
1.2 ml of water or 1.2-2.4 ml of 1/2-isotonic saline were injected into the duodenum of the unanaesthetized rat. Continuous measurements of conductivity and sodium concentration in whole blood, the last by means of ion-selective electrodes, and of protein and electrolyte concentration in a filtrate of portal vein blood were made. Whereas conductivity and sodium or electrolyte concentration dropped promptly and steeply, the drop of protein concentration (Cprot) was registered with a delay of 1.9 min. A quantitative comparison of the conductivity and sodium concentration curves, showing strictly synchronous courses, suggested that no hematocrit changes (these would have influenced conductivity) had taken place during the period of constancy of Cprot. In rats having thirsted for 36 h, Cprot did not fall during a period of 5-8 min in which they drank up to 5.5 ml of water, despite a great drop of electrolyte concentration. It is concluded that at the beginning of water absorption all the fluid absorbed is transported via the lymph ducts. A gradient of negative pressure from the interstitial tissues to the lymphatic system in the non-absorbing gut is proposed, an additional electrolyte secretory process being taken into consideration. 相似文献
12.
Y Wahbi R Caujolle C Tournaire M Payard M.D. Linas J.P. Seguela 《European journal of medicinal chemistry》1995,30(12)
Aromatic ethers related to antifungal azole miconazole were synthesized and tested against various strains of Candida. We found that activity is related to the nature of the aromatic ring and the position of substituents on this ring. Activity is more strongly dependent on the substituent in the 2 position of the ethyl chain than on the aromatic group linked through the oxygen. Triazoles were always less potent than the corresponding imidazole analogues. 相似文献
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Four cases of effort-related axillosubclavian thrombosis are described. The pathogenesis of this disorder is related to an anatomic constriction of the vein by the clavicle and first rib complex associated with repetitive trauma to the vein and resultant changes in the vein wall itself. Therapy must, therefore, not only address the superimposed thrombosis but must also provide a reliable correction of the constricting mechanism and the resultant lesion in the proximal subclavian vein. Our operative approach resulted in a full return to daily activities and no recurrence or persistence of symptoms in our series. Although early intervention is advisable, patients who present with long-standing venous occlusion should also be considered for operation. Medical therapy, consisting either of anticoagulation or thrombolytic therapy, results in an unsatisfactory clinical outcome because it does not correct the underlying mechanical abnormality. 相似文献
15.
Maggie L Naguib Iris Schrijver Phyllis Gardner Lynn M Pique Samiha S Doss Mona A Abu Zekry Mona Aziz Samya Z Nasr 《Journal of cystic fibrosis》2007,6(2):111-116
BACKGROUND: Knowledge about Cystic Fibrosis (CF) in Egypt is very limited. The objective of this study was to screen for CF in Egyptian children with suggestive clinical features and to identify causative genetic mutations. METHODS: Sixty-one patients from the Chest Unit, Cairo University Children's Hospital, Egypt, were included. Subjects presented with persistent or recurrent respiratory symptoms, failure to thrive, diarrhea and/or steatorrhea and unexplained persistent jaundice. Patients were screened using the CF Indicatortrade mark sweat test system (PolyChrome Medical, Inc., Brooklyn Center, MN). A quantitative sweat testing was conducted on 10 of the 12 positive patients. Seven probands and one sibling underwent molecular analysis by direct DNA sequencing of the coding region and of the intronic sequences adjacent to the 27 exons of the CFTR gene. RESULTS: Of 61 patients, 12 (20%) had positive sweat chloride screening. Ten of the 12 patients underwent quantitative sweat testing and were positive. Eight CFTR sequence changes were identified in seven affected probands and two were confirmed in one sibling by direct DNA sequencing. CONCLUSION: The study results suggest that CF is more common in Egypt than previously anticipated. Larger studies are warranted to identify the incidence, molecular basis and clinical pattern of CF in the Egyptian population. 相似文献
16.
A 17-year-old male presented to a local hospital with symptoms of pneumonia and a hacking cough productive of yellow sputum. Direct examination of a bronchial lavage sample revealed organisms morphologically consistent with Blastomyces dermatitidis, which was confirmed by culture. The patient was placed on intravenous antifungal therapy and his condition improved dramatically. OBJECTIVES: to describe the gross and microscopic morphologies of both yeast and mold forms of B. dermatitidis; to identify B. dermatitidis given patient history, and microscopic and colony morphology; to describe the symptoms of primary pulmonary infections caused by B. dermatitidis, and to name additional tissues typically affected by the systemic pathogen. 相似文献
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Detection of Vi-negative Salmonella enterica serovar typhi in the peripheral blood of patients with typhoid fever in the Faisalabad region of Pakistan 下载免费PDF全文
Baker S Sarwar Y Aziz H Haque A Ali A Dougan G Wain J Haque A 《Journal of clinical microbiology》2005,43(9):4418-4425
The synthesis and transportation proteins of the Vi capsular polysaccharide of Salmonella enterica serovar Typhi (serovar Typhi) are encoded by the viaB operon, which resides on a 134-kb pathogenicity island known as SPI-7. In recent years, Vi-negative strains of serovar Typhi have been reported in regions where typhoid fever is endemic. However, because Vi negativity can arise during in vitro passage, the clinical significance of Vi-negative serovar Typhi is not clear. To investigate the loss of Vi expression at the genetic level, 60 stored strains of serovar Typhi from the Faisalabad region of Pakistan were analyzed by PCR for the presence of SPI-7 and two genes essential for Vi production: tviA and tviB. Nine of the sixty strains analyzed (15%) tested negative for both tviA and tviB; only two of these strains lacked SPI-7. In order to investigate whether this phenomenon occurred in vivo, blood samples from patients with the clinical symptoms of typhoid fever were also investigated. Of 48 blood samples tested, 42 tested positive by fliC PCR for serovar Typhi; 4 of these were negative for tviA and tviB. Three of these samples tested positive for SPI-7. These results demonstrate that viaB-negative, SPI-7-positive serovar Typhi is naturally occurring and can be detected by PCR in the peripheral blood of typhoid patients in this region. The method described here can be used to monitor the incidence of Vi-negative serovar Typhi in regions where the Vi vaccine is used. 相似文献
19.
Topical treatments for seasonal allergic conjunctivitis: systematic review and meta-analysis of efficacy and effectiveness 总被引:3,自引:0,他引:3
Christopher G Owen Anupa Shah Katherine Henshaw Liam Smeeth Aziz Sheikh 《The British journal of general practice》2004,54(503):451-456
BACKGROUND: Evidence for the effectiveness of topical treatments, in providing symptomatic relief from ocular allergy, remains uncertain. AIMS: To assess the effectiveness and relative efficacy of topical treatments for the management of seasonal allergic conjunctivitis. DESIGN OF STUDY: A systematic review and meta-analysis. SETTING: A literature search of the Cochrane Library, Medline, and EMBASE bibliographic databases. METHOD: Double-masked randomised controlled trials were identified, that compared the use of topical mast cell stabilisers (sodium cromoglycate, nedocromil, lodoxamide) with placebo, topical antihistamines with placebo, and topical mast cell stabilisers with topical antihistamines. RESULTS: A meta-analysis of six trials showed that patients using sodium cromoglycate were 17 times (95% confidence interval [CI] = 4 to 78) more likely to perceive benefit compared with those using a placebo, although this estimate may be partially influenced by publication bias. Five trials indicated that those patients using nedocromil were 1.8 times (95% CI = 1.3 to 2.6) more likely to perceive their allergy to be moderately or totally controlled than those using a placebo. Four trials showed that those using antihistamines were 1.3 times (95% CI = 0.8 to 2.2) more likely to perceive a 'good' treatment effect than those using mast cell stabilisers, although this beneficial effect was not statistically significant. Limited evidence suggests that antihistamines might have a faster therapeutic effect compared to mast cell stabilisers. CONCLUSION: Overall, these findings confirm the benefit of topical mast cell stabilisers and antihistamines over placebo for the treatment of allergic conjunctivitis. There is, however, insufficient evidence to recommend the use of one type of medication over another. Treatment preferences should therefore be based on convenience of use (with reduced frequency of instillation for some preparations), patient preference, and costs, especially as important side effects were not reported with any medication. 相似文献
20.
A prospective seroepidemiological study of rotavirus infection was performed in children in a village in rural Bangladesh. Ninety-three percent of the children had detectable antibodies during the study, and there were 66 significant rises in titer occurring in 57 of the 85 children. Antibody titer rises occurred in older children and younger children with equal frequency. Nine children (11%) had evidence of multiple infections during the 16-month period. Winter infections were most frequent, although one summer (monsoon) season was also associated with a large cluster. Subjects with high titers (greater than 1:8) of antibody less frequently developed a titer rise than did subjects with lower titers. 相似文献