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91.
Abstract –  To evaluate the frequency and causes of dental and maxillofacial trauma in hospitalized patients. From January 1, 2000 to December 31, 2003, data from hospitalized trauma patients in a level 1 trauma center in Israel were analyzed according to age, gender, time, place, and cause of injury. Maxillofacial and tooth injuries were separated and further analyzed according to the above parameters. The analysis was based on data from the Israel Trauma Registry (ITR). Of all 14 040 trauma patients, 1038 (7.4%) involved maxillofacial or dental injuries. Common causes of injury were motor vehicle crashes (41%), falls (27%) and intentional injuries (23%). Fifty percent occurred on the street/road, 17% at home and 14% in public buildings. Surgery was required in 55.5% of all maxillofacial injuries. Males were hospitalized three times more than females, and young people, ages 19–28, were at greatest risk (30.2%). Oral and maxillofacial trauma is common, requiring dental health training for primary caregivers.  相似文献   
92.

Background

Cranioplasty is a surgical procedure used to treat a bone defect or deformity in the skull. To date, there is little consensus on the standard-of-care for graft materials used in such a procedure. Graft materials must have sufficient mechanical strength to protect the underlying brain as well as the ability to integrate and support new bone growth. Also, the ideal graft material should be individually customized to the contours of the defect to ensure a suitable aesthetic outcome for the patient.

Purpose

Customized 3D-printed scaffolds comprising of polycaprolactone-β-tricalcium phosphate (PCL-TCP) have been developed with mechanical properties suitable for cranioplasty. Osteostimulation of PCL-TCP was enhanced through the addition of a bone matrix-mimicking heparan sulphate glycosaminoglycan (HS3) with increased affinity for bone morphogenetic protein-2 (BMP-2). Efficacy of this PCL-TCP/HS3 combination device was assessed in a rat critical-sized calvarial defect model.

Method

Critical-sized defects (5 mm) were created in both parietal bones of 19 Sprague Dawley rats (Male, 450–550 g). Each cranial defect was randomly assigned to 1 of 4 treatment groups: (1) A control group consisting of PCL-TCP/Fibrin alone (n = 5); (2) PCL-TCP/Fibrin-HSft (30 μg) (n = 6) (HSft is the flow-through during HS3 isolation that has reduced affinity for BMP-2); (3) PCL-TCP/Fibrin-HS3 (5 μg) (n = 6); (4) PCL-TCP/Fibrin-HS3 (30 μg) (n = 6). Scaffold integration and bone formation was evaluated 12-weeks post implantation by μCT and histology.

Results

Treatment with PCL-TCP/Fibrin alone (control) resulted in 23.7% ± 1.55% (BV/TV) of the calvarial defect being filled with new bone, a result similar to treatment with PCL-TCP/Fibrin scaffolds containing either HSft or HS3 (5 μg). At increased amounts of HS3 (30 μg), enhanced bone formation was evident (BV/TV = 38.6% ± 9.38%), a result 1.6-fold higher than control. Further assessment by 2D μCT and histology confirmed the presence of enhanced bone formation and scaffold integration with surrounding host bone only when scaffolds contained sufficient bone matrix-mimicking HS3.

Conclusion

Enhancing the biomimicry of devices using a heparan sulphate with increased affinity to BMP-2 can serve to improve the performance of PCL-TCP scaffolds and provides a suitable treatment for cranioplasty.  相似文献   
93.
Alloys, in which the main constituents are palladium and titanium, have the following potential advantages for dental application: corrosion resistance, biocompatibility and acceptable casting temperatures for porcelainfused-to-metal dental prostheses. Alloy compositions chosen for investigation were as follows: 30 w/o Ti which lies in the 5% single-phase region near TiPd, 50 w/o Ti which lies near the 1120°C melting temperature minimum of the Pd?Ti system, and 70% Ti which minimizes Pd content while still in a relatively low melting range (1300°C). Analysis of the X-ray diffraction of 70%Pd30%Ti showed mostly PdTi with some Pd5Ti3; in 50%Pd50%Ti mostly PdTi2 was observed with some PdTi; in 30%Pd70%Ti mostly PdTi2 was found with some alpha Ti and PdTi4. The amounts of the minor phases in each of the 3 alloys depended on heat treatment. The Knoop hardness of the alloys ranged from 300–500 KHN for the as-melted condition; after heat treatment the maximum hardness values were 400 KHN. After centrifugal casting, hardness values increased to a range of 350 to 560 KHN, depending on composition. These values exceed those obtained for the pure metals which were in the neighborhood of 100 KHN. From anodic potentiodynamic scans the breakdown potentials in Ringer's solution for 70%Pd30%Ti, 50%Pd50%Ti and 30%Pd70%Ti were 600, 650 and 500 (SCE); the repassivation potentials for the same alloys are 450, 300 and 350 (SCE), respectively. These are all above oral potential. The Pd?Ti system investigated was, thus, found to have adequate corrosion resistance and hardness. Therefore, it can be considered of good potential as a dental prosthetic alloy.  相似文献   
94.
95.
目的了解小学生口腔状况及卫生保健行为,分析影响口腔健康的相关因素,探索切实可行的口腔预防保健措施。方法采用口腔检查、唾液隐血试验及问卷调查表对南京市鼓楼区随机抽取的80名五年级小学生进行调查。结果受检小学生唾液隐血阳性率为42.3%,不同性别间的差别无显著性。喜软食组唾液隐血阳性率较阴性组显著增高(P<0.05),阳性组就餐时间较阴性组显著减少(P<0.05),阳性组的错位牙者较阴性组显著增多(P<0.05),在牙齿拥挤度(≥4mm)及前牙深覆盖上(>5mm)均较阴性组有显著增高(P<0.05)。结论要加强对小学生的口腔卫生保健,合理安排其膳食时间及食物搭配,积极矫正错畸形的发生。  相似文献   
96.
目的:初步研究热休克蛋白47(HSP47)重组质粒pTraeer—CMV—HSP47局部注射对糖尿病大鼠皮肤创口愈合的影响,探讨以HSP47质粒为摹础的基因治疗促进糖尿病皮肤创口愈合的可行性和有效性.方法:制备四氧嘧啶诱导的糖尿病大鼠皮肤创口愈合模型,创缘皮下局部注射HSP47重组质粒,观察其对皮肤创口愈合的影响,并用免疫组织化学、荧光定量RT—PCR、Western blotting检测创口愈合过程中HSP47和collagen Ⅰ的表达变化。结果:在糖尿病大鼠皮肤刨缘连续两次注射质粒后第3、6、9天.免疫组织化学、荧光定量RT-PCR和Western blotting检测证实,HSP47重组质粒组比对照组能显著增加创口中的HSP47和collagenⅠ的表达。结论:在糖尿病大鼠皮肤创口周围注射质粒pTracer—CMV—HSP47,能明显增强HSP47和coilagenⅠ的表达,有助于改善创口愈合,HSP47可能是促进糖尿病皮肤创口愈合的潜在治疗靶点。  相似文献   
97.
菌斑固相、变形链球菌及葡聚糖对酸的缓冲作用   总被引:1,自引:0,他引:1  
目的研究糖代谢后菌斑固相缓冲力的变化及影响因素。方法采集40名18~21岁的大学生的饥饿牙菌斑,体外10%蔗糖孵育1h。体外制备无糖培养和2%蔗糖培养的变链菌团。以25mmol/L KCl制备菌斑固相、变链菌团和不溶性葡聚糖混悬液及可溶性葡聚糖溶液,用1mmol/LHCl滴定并计数细菌密度,统计学分析。结果变链菌团代谢蔗糖后的缓冲容量为(0·099±0·047)mmol/L,比无蔗糖培养的变链菌团的缓冲容量(0·609±0·202)mmol/L低,且缓冲力随细菌密度降低直线下降,葡聚糖几乎没有缓冲作用[(0·028~0·032)mmol/L]。人牙菌斑固相缓冲力的变化规律与体外纯菌培养研究结果一致。结论菌斑固相缓冲力与所含细菌密度密切相关。  相似文献   
98.
630名四川农村成人牙本质敏感流行病学调查分析   总被引:1,自引:0,他引:1       下载免费PDF全文
目的 了解四川省农村成人牙本质敏感的患病状况,并探讨可能的危险因素.方法 采用多阶段、分层、等容量、随机抽样的方法,对四川省农村630名成人进行牙本质敏感问卷调查和口腔临床检查,使用SPSS 18.0软件对调查数据进行统计分析.结果 四川省农村成人牙本质敏感的患病率为27.9%,酸刺激是最常见的敏感诱发因素.第一前磨牙...  相似文献   
99.
The main purpose of the National Nutrition and Health Systematic Survey for children 0-17 years of age in China (CNHSC) was to collect basic data on the nutrition, development, and health status for children in different regions across China using evidence-based, reliable, and cost-effective approaches. Children and their parents or guardians from seven regions (south, southwest, north, northwest, eastern, central, and northeast China) in China were recruited. A multi-stage stratified randomized sampling method was used. Two provinces were randomly sampled from each of the seven regions, from which one urban district and one rural country were also randomly sampled, resulting in a total of 28 survey counties/districts. Dietary surveys, health examinations, laboratory testing, and questionnaires were used to collect dietary intake, nutritional status, child development, and health status information. Nutrition, health, and lifestyle assessment of children and their parents was determined using the Knowledge Attitude Practice (KAP) survey. Greater than 100,000 children (38,000 children < 6 years of age and 66,000 children 6-17 years of age) completed the survey. The survey provided comprehensive data on child nutrition and health status for future studies and will serve as the basis for an integrated nutrition and health improvement strategies proposal for children in China.  相似文献   
100.
Objective This study was performed to compare the genetic diversity, virulence, and antimicrobial resistance of Aeromonas strains isolated from patients and healthy individuals. Methods A total of 38 clinical strains and 19 strains from healthy individuals were isolated from the samples collected in Ma'anshan City, Anhui Province. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, and their resistance to 12 antibiotics was evaluated. The pathogenicity of these strains was examined through beta-hemolysis, protease activity, and virulence gene assays. Results The 57 Aeromonas strains were divided into 55 sequence types. Of these types, 21 were novel, suggesting that their genetic diversity was high. These Aeromonas isolates could be divided into 7 species, and the positive rates of beta-hemolysis and protease activity were 49.1% and 73.7%, respectively. The detection rate of clinical patients in terms of beta-hemolysis and protease activity was higher than that of healthy individuals. Among the four most common Aeromonas strains, A. dhakensis had the highest detection rate of virulence genes. The multidrug resistance rate of the clinical isolates was much higher than that of the strains isolated from healthy individuals. Conclusions The taxonomy, virulence properties, and antibiotic resistance of Aeromonas isolates from patients differ from those of the isolates from healthy individuals.  相似文献   
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