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991.
992.
Using polymerase chain reaction (PCR)-based sequence-specific primers, the killer immunoglobulin-like receptor (KIR) genotypes of 35 patients with natural killer (NK)-type lymphoproliferative disease of granular lymphocytes and of 50 normal subjects were investigated to evaluate whether genes coding for activating KIRs were more frequently detected in patients with NK-lymphoproliferative disease of granular lymphocytes (LDGL). Genotype frequency indicated that the most frequently found gene content was eight genes in controls and 14 in patients (P<0.05). The KIR genotype analysis revealed that patient and, surprisingly, control KIR genotypes preferentially consisted of type B haplotypes characterized by the presence of multiple-activating KIRs. Evidence was also provided that the same KIR genotype was shared by a variable number of patients. Interestingly, the recurrent genotypes observed in the patient group were not found in controls. Concerning inhibitory genes, KIR2DL5a and 2DL5b were more frequently detected in patients than in controls (P<0.01), likely representing a discrete feature of the genetic repertoire of the patients. KIR gene repertoire analysis in patients suggests that the susceptibility to NK-LDGL might be related to the presence of activating KIR genes and supports the concept that these receptors may be involved in the priming of granular lymphocytes (GL) proliferation. Population analysis might disclose a genetic background predisposing to this disease.  相似文献   
993.
994.
AIM: Microbes commonly involved in ventilator associated pneumonia (VAP) are difficult to eradicate: Pseudomonas aeruginosa and Acinetobacter baumannii are often resistant to piperacillin, aztreonam and ceftazidim while Klebsiella pneumoniae and other Enterobacteriaceae are resistant to third generation cephalosporins. Physicians need to tailor their therapeutic approach depending on individual patients and clinical setting, firmly based on local epidemiology. The aim of this study was to assess the incidence of VAP caused by multidrug-resistant bacteria in our ICU. METHODS: We conducted a retrospective review of all patients mechanically ventilated for longer than 72 h, who developed pneumonia over an eighteen-month period for whom final culture data were available. One-hundred and forty-three patients admitted to a University Hospital medical surgical ICU were included in this survey. VAP was diagnosed by Centers for Disease Control and Prevention criteria and confirmed by mini- bronchoalveolar lavage. RESULTS: In this study, the incidence of VAP in the period January 1, 2002-June 31, 2003 was very high, accounting for about 20% of all at-risk cases. Multiresistant agents were involved in about 57% of VAP occurring within 7 days of mechanical ventilation, and in 80% of late VAP. CONCLUSIONS: This study revealed differences in VAP incidence and features among our ICU and literature data, indicating a need for caution when using hospital infection surveillance data for comparisons and choice of therapy. In our setting, with high levels of antibiotic resistance, combined approaches of non-antibiotic using strategies and education programs might be beneficial.  相似文献   
995.
Knowledge of the location of the subtalar joint axis in individual patients would permit clinical assessment of the forces and moments that produce frontal-plane foot and ankle deformities. Biomechanical analysis of the subtalar joint is hindered, however, by the inaccessibility of the talus, which makes locating the joint axis difficult, and by the high degree of intersubject anatomic variation. This article discusses work done with cadaver specimens and using invasive methods in vivo that has enhanced our understanding of the mechanics of the subtalar joint and its function during gait. Also reviewed are investigations of the actions of muscles that cross the subtalar joint.  相似文献   
996.

Background

170 million people are infected with the Hepatitis C virus (HCV) around the world. Approximately 50%-70% patients infected with HCV develop chronic liver disease. Haemodialysis patients constitute an especially important group with high HCV prevalence. Outbreaks of HCV infection in dialysis units have been documented. Detection of anti-HCV antibodies is a convenient and conventional mode of documentation. However, in this group, it has it''s own caveats.

Methods

48 patients who had undergone or were on haemodialysis (HD) and had undergone a minimum of 15 dialysis sittings were studied. HCV infection was documented both by anti-HCV antibody detection and HCV RNA testing. A comparative evaluation of results by both tests was done.

Results

Out of a total of 48 patients, HCV RNA was detected in 38 (79.16%) and anti-HCV antibodies in 13(27.07%). Out of 48 patients 10(20.83%) were negative for both parameters. 22.91% (11/48) of patients were positive for both HCV RNA and anti-HCV antibody. 56.25% (27/48) were HCV RNA positive but anti-HCV antibodies were not detectable in their sera. 2 patients (04.16%) had a positive anti-HCV antibody status despite HCV RNA being negative. In 20.83% (10/48) both parameters were undetectable.

Conclusion

Chronic liver disease (CLD), particularly due to HCV infection, is a major complication amongst haemodialysis (HD) patients. Without reliable assays for antigenemia and the inability of antibody tests to define viremia in all cases, the detection of viral nucleic acid is necessary for diagnosis of active HCV infection.Key Words: Hepatitis C virus, Haemodialysis  相似文献   
997.
OBJECTIVE: To evaluate the sensitivity, specificity, accuracy, and predictive values of magnetic resonance imaging (MRI) in the assessment of mandibular involvement in oral-oropharyngeal squamous cell carcinoma. DESIGN: Prospective study. SETTING: University hospital. PATIENTS: Forty-three patients with oral or oropharyngeal squamous cell carcinoma undergoing marginal or segmental mandibulectomy between January 1, 1994, and January 31, 2003. INTERVENTIONS: Indications for mandibulectomy were MRIs suggestive of bony invasion, tumor involving the retromolar trigone or the alveolar ridge, recurrent or persistent lesion, or intraoperative suspicion of periosteal invasion. Detection of tumor signal replacing the hypointense cortical rim was considered the main radiologic finding for mandibular invasion. MAIN OUTCOME MEASURES: The MRI findings were subsequently compared with histopathologic data of surgical specimens with reference to the presence of cortical and/or medullary mandibular involvement. RESULTS: Sixteen patients had MRI findings suggestive of mandibular involvement. Segmental mandibulectomy was performed in 15 cases and marginal resection in the remaining case. In 14 patients, bony invasion was confirmed. All of the other 27 patients who underwent marginal or segmental mandibulectomy with negative MRI findings had no histopathologic evidence of mandibular involvement, except in 1 patient: on histopathologic examination, despite cortical integrity, neoplastic vascular embolization into the bony lacunae was detected. Sensitivity of MRI in detecting mandibular involvement was 93%; specificity, 93%; accuracy, 93%; and negative and positive predictive values, 96% and 87.5%, respectively. CONCLUSIONS: Magnetic resonance imaging is commonly considered the technique of choice for treatment planning in advanced oral and oropharyngeal squamous cell carcinoma because of its accuracy in depicting soft-tissue involvement. This study demonstrates the additional diagnostic value of MRI in detecting bone invasion.  相似文献   
998.
AIM: It has been reported that rhythmic gymnasts are at risk of suffering from low back injuries, because of repetitive lumbar hyperextensions. On the other hand, this sport requires features of leanness, muscular strength and flexibility that should represent protective factors for back pain. METHODS: This cross-sectional study aimed to assess the prevalence of low back pain in 67 club-level competitive rhythmic gymnasts aged 13-19 years. A standardized questionnaire was used to evaluate back-pain symptoms. Anthropometric measurements, time spent in physical activity, psychological testing results, smoking habits and age of menarche were recorded. One hundred and four age-matched general females served as control group. RESULTS: Low back pain complaints were reported by 7 rhythmic gymnasts and by 27 controls (10.4% vs 26.0%, p<0.05); the prevalent location of back pain was bilateral in gymnasts and central in controls. Gymnasts had lower body weight, body mass index, fat body mass and delayed menarche. The females with low-back pain displayed higher body weight, body mass index, fat body mass, age, a greater smoking habit and more anxious/depressive behaviour, both in the gymnast and in the control group. CONCLUSION: Competitive, club-level rhythmic gymnasts show a reduced prevalence of low back-pain. Being younger in age, having greater leanness, not smoking, displaying less anxious/depressive behaviour, and developing increased muscle strength and flexibility, all can represent preventive factors for low back pain. This study suggests that rhythmic gymnastics is not a discipline at increased risk of low back pain.  相似文献   
999.
1000.
AIM OF THE STUDY: Evaluation of hearing results after implantation of a fluoroplastic-platinum piston (FP) and of a titanium piston (T) with a shaft diameter of respectively 0.6 mm and 0.4 mm, in cases of otosclerosis requiring stapedotomy. MATERIAL AND METHODS: Pre-operative and post-operative hearing results obtained after primary stapedotomy by implantation of 30 FP and 30 T performed by the same expert author (C.Z.) were reviewed. In each patient we evaluated pre- and post-operative auditory thresholds, as recommended. RESULTS: All patients of both groups showed a significant air-bone gap (ABG) improvement for all frequencies after surgery ( P < 0. 001). Post-operative ABG comparison between the two groups showed a better ABG for lower frequencies in the FP group and for higher frequencies in the T group, but the difference was not significant. No post-operative complications, including sensorineural hearing loss, were found. Bone conduction improvement was better in the FP group than in the T one and this difference was statistically significant at 1000 and 2000 Hz. There was no statistically significant difference in the post-operative outcomes between the two prosthesis. Better results of FP for lower frequencies suggest that an increase in diameter of the prosthesis results in a greater improvement in the hearing threshold at low frequencies, while a decrease of diameter results in a greater improvement in the hearing threshold at high frequencies, as indicated by previous international studies. CONCLUSION: Our data shows that titanium piston is a as good as fluoroplastic piston in stapes surgery for otosclerosis.  相似文献   
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