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991.
992.
An unexpected experimental pitfall in the molecular diagnosis of bacterial endophthalmitis 下载免费PDF全文
Ugahary L van de Sande W van Meurs JC van Belkum A 《Journal of clinical microbiology》2004,42(11):5403-5405
General primer-mediated ribosomal DNA amplification during endophthalmitis may improve the quality of diagnostic microbiology. However, extreme care needs to be taken not to introduce contaminating bacterial DNA during surgery procedures. The use of decontaminating iodine solutions can lead to such contamination due to the presence of DNA from Pseudomonas-like organisms. 相似文献
993.
Reducing motor-vehicle collisions, costs, and fatalities by treating obstructive sleep apnea syndrome 总被引:7,自引:0,他引:7
STUDY OBJECTIVES: Drivers suffering from obstructive sleep apnea syndrome (OSAS) have an increased risk for being involved in motor-vehicle collisions. This study estimates, for the first time, the annual OSAS-related collisions, costs, and fatalities in the United States and performs a cost-benefit analysis of treating drivers suffering from OSAS with continuous positive airway pressure (CPAP). DESIGN: The MEDLINE-PubMed database (1980 to 2003) was searched for information on OSAS. A meta-analysis was performed of studies investigating the relationship between collisions and OSAS. Data from the National Safety Council were used to estimate OSAS-related collisions, costs, and fatalities and their reduction with treatment. Next, the annual cost of treating OSAS with CPAP was calculated. Finally, multiple 1-way sensitivity analyses were performed. SETTING: N/A. PATIENTS OR PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: More than 800,000 drivers were involved in OSAS-related motor-vehicle collisions in the year 2000. These collisions cost 15.9 billion dollars and 1,400 lives in the year 2000. In the United States, treating all drivers suffering from OSAS with CPAP would cost 3.18 billion dollars, save 11.1 billion dollars in collision costs, and save 980 lives annually. CONCLUSION: Annually, a small but significant portion of motor-vehicle collisions, costs, and deaths are related to OSAS. With CPAP treatment, most of these collisions, costs, and deaths can be prevented. Treatment of OSAS benefits both the patient and the public. 相似文献
994.
Selective serotonin reuptake inhibitors (SSRIs) are well-established medications for the treatment of mood disorders including major depression. These agents are also known to exhibit potent antiplatelet and endothelium protective effects effects. Additionally, SSRIs can exacerbate the development of inflammation, and modulate the interleukin and interferon production. All of the above suggest that SSRIs therapy could be considered as a potential strategy for the wound healing treatment. We summarized some body of the available data on the history of serotonin metabolism, mechanism of action of ketanserin, and hypothesize why SSRIs may be beneficial in the wound repair natural history. Different pathophysiological considerations are also reflected in this review. Finally, we suggest that the topical use of SSRIs may represent a promising avenue for future strategies affecting wound repair in high-risk patients, especially those with diabetes mellitus, venous insufficiency, obesity, and other vascular disorders. 相似文献
995.
Bojarczuk CC Lopes HS Freitas AA Michalkiewicz EL 《Artificial intelligence in medicine》2004,30(1):27-48
This paper proposes a new constrained-syntax genetic programming (GP) algorithm for discovering classification rules in medical data sets. The proposed GP contains several syntactic constraints to be enforced by the system using a disjunctive normal form representation, so that individuals represent valid rule sets that are easy to interpret. The GP is compared with C4.5, a well-known decision-tree-building algorithm, and with another GP that uses Boolean inputs (BGP), in five medical data sets: chest pain, Ljubljana breast cancer, dermatology, Wisconsin breast cancer, and pediatric adrenocortical tumor. For this last data set a new preprocessing step was devised for survival prediction. Computational experiments show that, overall, the GP algorithm obtained good results with respect to predictive accuracy and rule comprehensibility, by comparison with C4.5 and BGP. 相似文献
996.
Mlynarek A Tewfik MA Hagr A Manoukian JJ Schloss MD Tewfik TL Choi-Rosen J 《The Journal of otolaryngology》2004,33(6):360-365
OBJECTIVE: To evaluate the usefulness of adynamic lateral neck radiographs and dynamic video rhinoscopy in assessing adenoid size and the relationship of these methods to associated symptoms and thus the severity of the disease. METHODS: Children with suspected adenoid hypertrophy underwent standard lateral neck soft tissue radiographs: the percentage of airway occlusion, adenoid to nasopharynx (AN) ratio, airway to soft palate ratio, and adenoid thickness were assessed by a radiologist. The percentage of airway closure was assessed by direct fibre-optic rhinoscopy in an ear, nose, and throat clinic. Associated clinical symptoms were assessed by parents using a standardized questionnaire, evaluating the severity of symptoms (snoring, sleep apnea, mouth breathing, and otitis media) to give a total symptom score out of 16. RESULTS: Nonparametric statistical analysis using Spearman's correlation coefficients was performed on 32 patients. There was a weak correlation, which approaches significance, between the percentage of airway occlusion assessed by fibre-optic rhinoscopy and the total symptom score (r = .344, p = .054). However, this correlation becomes significant when the frequency of otitis media is omitted (r = .367, p = .039). There was also a significant correlation between airway occlusion assessed by rhinoscopy and the percentage of airway occlusion as determined by lateral neck radiography (r = .431, p = .014). There was no correlation between any of the measurements taken by lateral soft tissue neck radiography and total symptom score. CONCLUSION: Dynamic video rhinoscopy is more accurate at assessing adenoid hypertrophy, and the percentage of airway occlusion, as estimated by video rhinoscopy, is better correlated to the severity of symptoms than are values obtained by lateral neck radiography. 相似文献
997.
Sewell DA Douven D Pan ZK Rodriguez A Paterson Y 《Archives of otolaryngology--head & neck surgery》2004,130(1):92-97
BACKGROUND: Human papillomavirus (HPV) has been implicated in the pathogenesis of 15% to 23% of head and neck squamous cell carcinomas as well as most oropharyngeal carcinomas. The viral oncoproteins E6 and E7 are expressed in HPV-positive tumor cells and therefore provide ideal targets for tumor immunotherapy. Because of its unique ability to induce a cellular immune response, the intracellular bacteria Listeria monocytogenes has been studied as a potential HPV-positive tumor vaccine. OBJECTIVE: To present a new recombinant strain of L monocytogenes that is effective in treating HPV-positive tumors in a murine model. DESIGN: A new recombinant L monocytogenes vaccine, Lm-ActA-E7, was designed by transforming an attenuated Listeria strain with an E7 expression cassette. The cassette consists of the HPV-16 E7 sequence fused to the Listeria protein ActA. The resultant strain of bacteria secretes E7 antigen as a fusion protein with ActA. METHODS: Tumors were established in C57BL/6 mice with a syngeneic HPV-positive cell line prior to treatment with vaccine. INTERVENTION: The Lm-ActA-E7 vaccine was administered intraperitoneally to the mice 5 days after tumors were established. A booster dose was administered 7 days after the first dose. Tumor progression was measured in 2 dimensions periodically after the vaccination. RESULTS: In C57BL/6 mice, the administration of Lm-ActA-E7 caused the complete regression of HPV-positive tumors in 6 of 8 mice tested. A cytotoxic T-lymphocyte assay revealed that administration of the vaccine caused the generation of cytotoxic T cells specific for E7. CONCLUSION: Our results demonstrate the ability of a new Listeria-based vaccine to generate a specific antitumor T-cell response and cause the regression of HPV-positive tumors in a murine model. 相似文献
998.
Wilcox MH Freeman J Fawley W MacKinlay S Brown A Donaldson K Corrado O 《The Journal of antimicrobial chemotherapy》2004,54(1):168-172
OBJECTIVES: We followed the effects of changes to a new antibiotic policy favouring a ureidopenicillin as opposed to a third-generation cephalosporin on the long-term incidence of Clostridium difficile diarrhoea (CDD) and antibiotic utilization in a large Elderly Medicine Unit. PATIENTS AND METHODS: In 1999, piperacillin-tazobactam was added to the formulary in Elderly Medicine and its use promoted in preference to cefotaxime. Following review and feedback to clinicians of surveillance data, cefotaxime prescribing was actively restricted during 2000-2001. An audit of prescriber adherence to antibiotic policy was carried out by reviewing the records of 159 patients during February-April 2001. In December 2001, due to manufacturer production problems, supply of piperacillin-tazobactam was stopped. We performed standardized period prevalence surveillance (February-April) allowing comparisons of antibiotic utilization and CDD incidence during the 5 year study period (1998-2002). RESULTS: CDD incidence did not change significantly (P>0.1) during 1998-1999 despite a marked increase in piperacillin-tazobactam prescribing. However, when cefotaxime prescribing was curtailed in 2001, CDD rates decreased (in four of five wards) and overall by 52% (P=0.008). When piperacillin-tazobactam became unavailable in 2002, despite advice to the contrary cefotaxime prescribing rose five-fold, and CDD rates increased in four of five wards and by 232% (P<0.01) overall. Adherence to antibiotic policy introduced in 2000 was good (81% accordance); 94%, 88% and 73% of patients with cellulitis, urinary tract and respiratory tract infection, respectively, received appropriate antibiotics. CONCLUSIONS: Long-term prescribing of piperacillin-tazobactam in Elderly Medicine in preference to cefotaxime is associated with reduced rates of CDD. However, unless cephalosporin prescribing is curtailed, the beneficial effects on CDD rates may be missed. This is one of few studies to document adverse effects due to loss of antibiotic supply. 相似文献
999.
1000.
Tapp RJ Zimmet PZ Harper CA de Courten MP Balkau B McCarty DJ Taylor HR Welborn TA Shaw JE;Australian Diabetes Obesity Lifestyle Study Group 《Diabetes care》2004,27(3):688-693
OBJECTIVE: The aim of this work was to study the frequency of examining for diabetic eye and foot complications in an Australian population and to study factors associated with regular screening. RESEARCH DESIGN AND METHODS: The Australian Diabetes, Obesity, and Lifestyle Study (AusDiab) was a population-based study of 11,247 people from randomly selected areas of Australia. Participants identified as having previously diagnosed diabetes (n=475) were invited to participate in the complications study. Measures included foot examination, retinopathy photography, and self-report use of health care services. RESULTS: Seventy-seven percent of participants reported having an eye examination within the previous 2 years, and 50% reported having their feet examined by a health professional in the previous year. Type of diabetes treatment (odds ratio 1.46, 95% CI 0.85-2.50 for tablets versus diet alone and 4.17, 1.71-10.17 for insulin or insulin and tablets versus diet alone) and visiting a diabetes nurse educator in the previous 12 months (2.14, 1.18-3.87) were independent predictors of having had an eye examination. Duration of diabetes (1.33, 1.06-1.67 per year) and visiting a diabetes nurse educator in the previous 12 months (1.89, 1.20-2.95) were independent predictors of a foot examination. CONCLUSIONS: This study has shown that retinopathy screening is performed more frequently than foot screening in Australia. This may be due to the implementation of eye screening programs and awareness campaigns. Foot screening appears to be poor, with less than one-half of the population reporting a regular examination for foot complications. In Australia, diabetes nurse educators play a key role in promoting screening for diabetes complications. 相似文献