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61.
目的 制备链亲和素(SA)标记的人白细胞介素21融合蛋白(SA-hIL-21),检测其生物学活性.方法 构建hIL21-SA-pET21及pET24a-SA-hIL21质粒,利用大肠杆菌BL21(DE3)表达两种双功能融合蛋白,并利用镍金属螯合层析柱(Ni-NTA)纯化,之后透析复性,Western blotting进行鉴定,最后利用MTT法检测hIL21-SA及SA-hIL21融合蛋白与抗CD3单克隆抗体(anti-CD3)共刺激人外周血淋巴细胞的增殖活性,流式细胞仪分析两种融合蛋白对生物素化的MB49肿瘤细胞的锚定修饰效率.结果 hIL21-SA及SA-hIL21重组融合蛋白在大肠杆菌中实现了高效表达,约占菌体蛋白的30%,经复性后hIL21-SA及SA-hlL21具有了双重活性,即不仅可以与抗CD3单抗共刺激淋巴细胞的增殖,而且具有了SA介导的高效结合已生物素化的MB49肿瘤细胞表面的功能(表面修饰效率95.18%,96.91%).结论 本实验成功研制了具有双重活性的hIL21-SA及SA-hlL21融合蛋白,两种融合蛋白的双功能活性无显著性差异,该项研究为SA/hIL21双功能融合蛋白应用于肿瘤疫苗以及肿瘤局部治疗奠定了基础.  相似文献   
62.
The interest in cervical total disc replacement (TDR) as an alternative to the so-far gold standard in the surgical treatment of degenerative disc disease (DDD), e.g anterior cervical discectomy and fusion (ACDF), is growing very rapidly. Many authors have established the fact that ACDF may result in progressive degeneration in adjacent segments. On the contrary, but still theoretically, preservation of motion with TDR at the surgically treated level may potentially reduce the occurrence of adjacent-level degeneration (ALD). The authors report the intermediate results of an undergoing multicentre prospective study of TDR with Mobi-C® prosthesis. The aim of the study was to assess the safety and efficacy of the device in the treatment of DDD and secondary to evaluate the radiological status of adjacent levels and the occurrence of ossifications, at 2-year follow-up (FU). 76 patients have performed their 2-year FU visit and have been analyzed clinically and radiologically. Clinical outcomes (NDI, VAS, SF-36) and ROM measurements were analyzed pre-operatively and at the different post-operative time-points. Complications and re-operations were also assessed. Occurrences of heterotopic ossifications (HOs) and of adjacent disc degeneration radiographic changes have been analyzed from 2-year FU X-rays. The mean NDI and VAS scores for arm and neck are reduced significantly at each post-operative time-point compared to pre-operative condition. Motion is preserved over the time at index levels (mean ROM = 9° at 2 years) and 85.5% of the segments are mobile at 2 years. HOs are responsible for the fusion of 6/76 levels at 2 years. However, presence of HO does not alter the clinical outcomes. The occurrence rate of radiological signs of ALD is very low at 2 years (9.1%). There has been no subsidence, no expulsion and no sub-luxation of the implant. Finally, after 2 years, 91% of the patients assume that they would undergo the procedure again. These intermediate results of TDR with Mobi-C® are very encouraging and seem to confirm the efficacy and the safety of the device. Regarding the preservation of the status of the adjacent levels, the results of this unconstrained device are encouraging, but longer FU studies are needed to prove it.  相似文献   
63.
The psychometric properties of the Obsessive-Compulsive Inventory-Revised (OCI-R) subscales have not been validated in a clinical sample of individuals diagnosed with obsessive-compulsive disorder (OCD). Data were collected on 186 patients diagnosed with OCD and 17 patients diagnosed with generalized anxiety disorder (GAD) using the OCI-R and the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Confirmatory factor analysis revealed an acceptable factor structure. Patients with a given primary symptom subtype were elevated on the corresponding subscale of the OCI-R compared to other OCD patients and patients with GAD. In addition, patients who acknowledged that symptom subtype as present but not primary on the Y-BOCS had elevated OCI-R scores on that scale compared to patients who did not endorse that symptom subtype and patients with GAD. Results indicate that the subscales of the OCI-R are valid measures of six symptom subtypes of OCD. The OCI-R is a psychometrically sound, brief instrument. The current data combined with previous efforts suggest that it is appropriate for clinical and non-clinical populations, and for clinical and research purposes. Further research should examine the sensitivity of the specific subscales to treatment effects, and the potential for adding more items to account for other symptom domains of OCD.  相似文献   
64.
Objectives: The Central Massachusetts Oral Health Initiative (CMOHI) aimed to improve access to quality oral health care in central Massachusetts. Methods: A broad‐based public and private organization partnership with local and national funding created a steering committee to organize school administrators, community leaders, and a medical school to collaborate on five goals: advocate for changes in oral health policy, increase oral health care access, provide school‐based dental services for underserved children, establish a Dental General Practice Residency, and educate medical professionals about oral health. Results: A state legislative Oral Health Caucus helped secure sought‐after policy improvements; more regional dentists now accept Medicaid; community health center capacity to provide dental services was expanded; school‐based programs were designed and delivered needed dental services; a dental residency was created; and methods of educating medical professionals were established. Conclusions: Significant sustainable gains in oral health care access were created through our multifaceted approach, ongoing evaluation and communication, coordination of CMOHI partner resources, and collaboration with other involved parties.  相似文献   
65.
To cite this article:
Int J Dent Hygiene
DOI: 10.1111/j.1601‐5037.2009.00427.x
Pickett FA. New guidelines for cardiac risk assessment prior to non‐cardiac surgery. Abstract: The European Society of Cardiology (ESC) has established guidelines to determine the risk for non‐cardiac procedures, such as oral procedures, when individuals have experienced severe cardiac disease, including myocardial infarction. This is the first time the ESC has developed consensus guidelines to assist practitioners in managing care for cardiac patients receiving medical or dental procedures. Factors for risk assessment are described and management for oral care is discussed.  相似文献   
66.

Background

Agricultural science can address a population's vitamin, amino acid and mineral malnutrition through biofortification - agronomy, plant breeding and biotechnology to develop crops with high nutrient contents. Biofortified crop varieties should be grown in areas with populations at risk of nutrient deficiency and in areas where the same crop is already grown and consumed. Information on the population at risk of nutrient deficiency is rarely available for sub-national administrative units, such as provinces, districts, and municipalities. Nor is this type of information commonly analyzed with data on agricultural production. This project developed a method to identify populations at risk of nutrient deficiency in zones with high crop production, places where biofortification interventions could be targeted.

Results

Nutrient deficiency risk data were combined with crop production and socioeconomic data to assess the suitability of establishing an intervention. Our analysis developed maps of candidate sites for biofortification interventions for nine countries in Latin America and the Caribbean. Results for Colombia, Nicaragua, and Bolivia are presented in this paper. Interventions in northern Colombia appear promising for all crops, while sites for bean biofortification are widely scattered throughout the country. The most promising sites in Nicaragua are found in the center-north region. Candidate sites for biofortification in Bolivia are found in the central part of the country, in the Andes Mountains. The availability and resolution of data limits the analysis. Some areas show opportunities for biofortification of several crops, taking advantage of their spatial coincidence. Results from this analysis should be confirmed by experts or through field visits.

Conclusion

This study demonstrates a method for identifying candidate sites for biofortification interventions. The method evaluates populations at risk of nutrient deficiencies for sub-national administrative regions, and provides a reasonable alternative to more costly, information-intensive approaches.  相似文献   
67.
我省长学制医学教育的回顾与思考   总被引:1,自引:0,他引:1  
我省七年制医学教育开办了近20年,为社会培养了一批深受欢迎、质量较好和具有较高综合素质的高层次医学人才。建立与我省经济发展水平相适应的以五年制为主体、重点发展八年制的医学教育学制体系,是我省高等医学教育发展的必然趋势。  相似文献   
68.
Dehydroepiandrosterone (DHEA) is a steroid that shows a marked age-related decline in humans. Previous research suggests potential for DHEA replacement in old age to enhance cognition and well-being. We conducted a clinical trial to test these hypotheses in a non-clinical sample of 46 men aged 62-76. Participants received either 50 mg DHEA daily for 13 weeks, followed by placebo for 13 weeks, or the reverse, in a randomised double-blind cross-over trial design. Levels of salivary cortisol and DHEA were measured at 0800 h and 2000 h prior to each assessment session. Cognition was assessed with tests of speed, attention and episodic memory. Well-being was measured with questionnaires of mood and perceived health. Mood questionnaires were completed at the assessment session as well as concurrently with saliva sampling.A correlational analysis of baseline behavioural data with hormonal data, controlling for age, revealed that higher morning DHEA was associated with lower confusion (r=-0.33; P=0.04), while higher evening DHEA was associated with lower anxiety (r=-0.35; P=0.03) and lower current negative mood in the morning (r=-0.37; P=0.03). Conversely, higher morning cortisol and a morning cortisol/DHEA ratio were associated with higher anxiety (r=0.35; P=0.03), (r=0.46; P=0.004), general mood disturbance (r=0.32; P=0.046), (r=0.32; P=0.04) and higher current negative mood in the evening (r=0.37; P=0.03), (r=0.38; P=0.03). A higher morning cortisol/DHEA ratio was also associated with higher confusion (r=0.39; P=0.01) and lower visuo-spatial memory performance (r=-0.39; P=0.01). Unexpectedly, higher evening cortisol was associated with faster choice reaction time (r=-0.33; P=0.04). These findings are consistent with an impairing effect of high cortisol on episodic memory and mood in older men, which may be attenuated by DHEA. When treatment effects were analysed, no significant effects of DHEA were observed on any of the trial outcomes, providing no support for benefits of DHEA supplementation for cognition or well-being in normal older men in the shorter-term.  相似文献   
69.
70.
Molecular ultrasound is capable of elucidating the expression of angiogenic markers in vivo. However, the capability of the method for volumetric "multitarget quantification" and for the assessment of antiangiogenic therapy response has rather been investigated. Therefore, we generated cyanoacrylate microbubbles linked to vascular endothelial growth factor receptor 2 (VEGFR2) and alphavbeta3 integrin binding ligands and quantified their accumulation in squamous cell carcinoma xenografts (HaCaT-ras-A-5RT3) in mice with the quantitative volumetric ultrasound scanning technique, sensitive particle acoustic quantification. Specificity of VEGFR2 and alphavbeta3 integrin binding microbubbles was shown, and changes in marker expression during matrix metalloproteinase inhibitor treatment were investigated. In tumors, accumulation of targeted microbubbles was significantly higher compared with nonspecific ones and could be inhibited competitively by addition of the free ligand in excess. Also, multimarker imaging could successfully be done during the same imaging session. Molecular ultrasound further indicated a significant increase of VEGFR2 and alphavbeta3 integrin expression during tumor growth and a considerable decrease in both marker densities after matrix metalloproteinase inhibitor treatment. Histologic data suggested that the increasing VEGFR2 and alphavbeta3 integrin concentrations in tumors during growth are related to an up-regulation of its expression by the endothelial cells, whereas its decrease under therapy is more related to the decreasing relative vessel density. In conclusion, targeted ultrasound appears feasible for the longitudinal molecular profiling of tumor angiogenesis and for the sensitive assessment of therapy effects in vivo.  相似文献   
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