全文获取类型
收费全文 | 187101篇 |
免费 | 12402篇 |
国内免费 | 5046篇 |
专业分类
耳鼻咽喉 | 2645篇 |
儿科学 | 2576篇 |
妇产科学 | 2203篇 |
基础医学 | 25834篇 |
口腔科学 | 4013篇 |
临床医学 | 18320篇 |
内科学 | 29487篇 |
皮肤病学 | 4568篇 |
神经病学 | 12608篇 |
特种医学 | 10092篇 |
外国民族医学 | 8篇 |
外科学 | 24581篇 |
综合类 | 14157篇 |
现状与发展 | 17篇 |
一般理论 | 30篇 |
预防医学 | 11779篇 |
眼科学 | 4274篇 |
药学 | 17613篇 |
57篇 | |
中国医学 | 5482篇 |
肿瘤学 | 14205篇 |
出版年
2024年 | 230篇 |
2023年 | 1505篇 |
2022年 | 4309篇 |
2021年 | 6660篇 |
2020年 | 3957篇 |
2019年 | 4396篇 |
2018年 | 5235篇 |
2017年 | 4661篇 |
2016年 | 5485篇 |
2015年 | 7901篇 |
2014年 | 9717篇 |
2013年 | 11133篇 |
2012年 | 16528篇 |
2011年 | 16291篇 |
2010年 | 10631篇 |
2009年 | 9186篇 |
2008年 | 11770篇 |
2007年 | 11244篇 |
2006年 | 10285篇 |
2005年 | 9176篇 |
2004年 | 7687篇 |
2003年 | 7044篇 |
2002年 | 6100篇 |
2001年 | 4718篇 |
2000年 | 3879篇 |
1999年 | 2801篇 |
1998年 | 1273篇 |
1997年 | 1048篇 |
1996年 | 787篇 |
1995年 | 663篇 |
1994年 | 563篇 |
1993年 | 435篇 |
1992年 | 843篇 |
1991年 | 797篇 |
1990年 | 705篇 |
1989年 | 611篇 |
1988年 | 510篇 |
1987年 | 508篇 |
1986年 | 368篇 |
1985年 | 398篇 |
1984年 | 273篇 |
1983年 | 205篇 |
1982年 | 145篇 |
1981年 | 176篇 |
1980年 | 135篇 |
1979年 | 229篇 |
1978年 | 170篇 |
1976年 | 134篇 |
1975年 | 127篇 |
1974年 | 146篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Eun Young Jung Hyung Joo Suh Wan Soo Hong Dong Geon Kim Yang Hee Hong In Sun Hong Un Jae Chang 《Nutrition Research》2009,29(7):457-461
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses. 相似文献
62.
Ki-Won Kim Kee-Yong Ha Jun-Seok Lee Suk-Woo Nam Young-Kyun Woo Tae-Hong Lim Howard S. An 《The spine journal》2009,9(4):323-329
Background contextIt was recently demonstrated that the postnatal transition from a notochordal to a fibrocartilaginous nucleus pulposus (NP) is accomplished exogenously by chondrocytes migrating from hyaline cartilage end plates (CEs) into the ectopic notochordal NP region. Although our previous in vivo studies showed evidences for the migration of CE chondrocyte from hyaline CEs into the notochordal NP, it is unknown whether CE chondrocytes of the intervertebral disc (IVD) really have a motile property. In addition, the effect of notochordal cells on this property has not been elucidated.PurposeThe purpose of this in vitro study was to demonstrate whether CE chondrocytes of the IVD are capable of migration, and whether there is any biological link between notochordal cells and CE chondrocytes that may regulate the CE chondrocyte migration.Study design/settingIn vitro cell migration assays were performed using rat IVDs.MethodsNotochordal cells and chondrocytes were obtained from the NP and CE tissues, respectively, and were cultured separately. The different numbers of notochordal cells and the supernatant (conditioned medium) that contained soluble factors produced by notochordal cells were used to demonstrate their effects on the migration of CE chondrocytes. Bovine serum albumin (BSA) and lysophosphatidic acid (LPA) were used as negative and positive controls, respectively.ResultsCompared with BSA, LPA, notochordal cells (N=4×, 2×, 1×, and 0.5×105), and its conditioned media (unconcentrated and fivefold concentrated) significantly increased migration of CE chondrocytes (p<.05 in all comparisons). Particularly, notochordal cells and its conditioned media increased migration in a number- and concentration-dependent manner, respectively.ConclusionsThis study demonstrates that CE chondrocytes of the IVD are capable of migration and that soluble factors produced by notochordal cells stimulate the migration. These results provide a plausible explanation to the question of why CE chondrocytes of the IVD migrate into the ectopic NP region during the natural transition from the notochordal to fibrocartilaginous NP. 相似文献
63.
Mark Sisco MD ; Jerome D. Chao MD ; Injoong Kim MD ; Jon E. Mogford PhD ; Tanya N. Mayadas PhD ; Thomas A. Mustoe MD 《Wound repair and regeneration》2007,15(4):566-571
The Mac-1 integrin is an important mediator of migration and inflammatory activation of neutrophils and monocytes. However, the role of Mac-1 in modulating macrophage emigration and activation and its subsequent impact on cutaneous wound healing have not been fully elucidated. To examine the significance of Mac-1 to murine wound healing, we measured epithelialization and granulation tissue formation in partial-thickness ear wounds and full-thickness head wounds, respectively, in Mac-1-deficient mice. Wounds were histologically analyzed at postwounding days 3, 5, and 7. The gap measured between the leading edges of inward-migrating granulation tissue was significantly increased in knockout mice compared with control animals at day 5 (3.8+/-0.3 vs. 2.6+/-0.5 mm; p<0.001) and day 7 (2.2+/-0.4 vs. 0.96+/-0.73 mm; p=0.005). Epithelial gap measurements were also increased in knockout mice vs. wild-type controls at days 3 (0.62+/-0.02 vs. 0.54+/-0.07 mm; p<0.05) and 5 (0.58+/-0.06 vs. 0.39+/-0.08 mm; p<0.001). Immunohistochemistry showed equal numbers of macrophages in knockout and control wounds. These findings show that Mac-1 is required for normal wound healing but that the attenuation in the deposition of granulation tissue and wound epithelialization in Mac-1 knockout mice is not associated with decreased monocyte migration into the wound. 相似文献
64.
Je-Yong Choi Hyung-Jong Kim Yong-Chan Lee Byoung-Ouck Cho Ha-Soo Seong Michael Cho Seong-Gon Kim 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(3):321-328
OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate. 相似文献
65.
66.
目的用新的生活质量量表研究癫痫患儿的生活质量并探讨其影响因素.方法用量表对71例符合标准的癫痫患儿的生活质量进行评估.结果癫痫患儿的生活质量明显低下,总评得分为63.13±18.89.发作频率、发作担忧及抑郁情绪与患儿生活质量呈负相关,相关系数分别为-0.42、-0.25和-0.45,而记忆功能与患儿生活质量呈正相关,相关系数为0.84.结论癫痫患儿的生活质量明显低下,对癫痫患儿进行药物治疗并辅以心理治疗、健康教育,能提高癫痫患儿的生活质量. 相似文献
67.
Kun Hwang MD PhD Ei Tae Kim MD Se Il Lee MD DMSc 《The Journal of foot and ankle surgery》2005,44(6):473-477
The purpose of this study was to determine the genetic characteristics of foot polydactyly and identify its inheritance pattern by analyzing familial pedigree. Five cases from 2 Korean families were studied: 1 is a family whose members have been affected for 4 generations and the other for 2 generations. Using peripheral blood samples, we performed chromosomal analysis using the banding technique with Giemsa stain and karyotyping. We investigated the shape and structure of 46 chromosomes, looking for translation, deletion, inversion, ring chromosome, and isochromosome abnormalities. All peripheral blood samples demonstrated no chromosomal abnormalities, though the genetic nature of foot polydactyly and a new genetic locus was identified recently by other studies. Familial pedigree analysis suggested that polydactyly was inherited as an autosomal dominant trait in the first family. The mode of inheritance for the second family could not be determined due to an insufficient number of family members. The result of this study brought us to the conclusion that, while genetic factors play a major role in polydactyly, other factors may contribute to its occurrence. 相似文献
68.
Hung J. Kim Torrance Jackson Konrad Noben–Trauth 《Journal of the Association for Research in Otolaryngology》2003,4(1):83-90
Genetic studies on spontaneous mouse mutants with hearing defects have provided important insights into the function of genes
expressed in inner ear hair cells. Here we report on our genetic analyses of the deaf mutants varitint-waddler (Va) and jerker
(Espnje). A high-resolution genetic map localizes VaJ to a 0.14 ± 0.08 cM region between D3Mit85 and D3Mit259 on distal chromosome
3. By comparative mapping, the human ortholog resides at 1p22.3 between markers D1S3449 and D1S2252. To study the effect of
different genetic backgrounds on the hearing phenotype, Espnje and VaJ were crossed to various inbred strains. Auditory-evoked
brainstem response tests on F2 progeny demonstrate that expression, inheritance, and penetrance of the hearing phenotype are
solely controlled by the mutant allele. To test for a genetic interaction between Espnje and Cdh23v, auditory function was
analyzed in double heterozygotes; no significant increases of thresholds of sound pressure levels were observed. The results
establish the framework for cloning the Va gene and provide valuable insights into the genetics of deafness mutations in the
mouse. 相似文献
69.
Andrew M Briggs John D Wark Susan Kantor Rayson Teh Alison M Greig Nicola L Fazzalari Kim L Bennell 《Journal of clinical densitometry》2005,8(3):314-319
Analysis of apparent bone mineral density (BMD) in the lumbar spine is commonly based on anteroposterior (AP) scanning using dual-energy X-ray absorptiometry (DXA). Although not widely used, clinically important information can also be derived from lateral scanning. Vertebral bone density, and therefore strength, can may vary in different subregions of the vertebral body. Therefore, subregional BMD measurements might be informative about fracture risk. However, the intrarater and interrater precision of in vivo subregional BMD assessments from lateral DXA remains unknown. Ten normal, young (mean: 24 yr) and 10 older (mean: 63 yr) individuals with low BMD were scanned on one occasion using an AP/lateral sequence. Each lateral scan was reanalyzed six times at L2 by three raters to determine the intrarater and interrater precision in selecting seven regions of interest (subregions). Precision was expressed using percentage coefficients of variation (% CV) and intraclass correlation coefficients (ICC). Intrarater precision ranged from ICC(1,1) 0.971 to 0.996 (% CV: 0.50-3.68) for the young cohort and ICC(1,1) 0.934 to 0.993 (% CV: 1.46-5.30) for the older cohort. Interrater precision ranged from ICC(2,1) 0.804 to 0.915 (% CV: 1.11-2.35) for the young cohort and ICC(2,1) 0.912 to 0.984 (% CV: 1.85-4.32) for the older cohort. Scanning a subgroup of participants twice with repositioning was used to assess short-term in vivo precision. At L2, short-term in vivo precision ranged from ICC(1,1) 0.867 to 0.962 (% CV: 3.38-9.61), at L3 from ICC(1,1) 0.961 to 0.988 (% CV: 2.02-5.57) and using an L2/L3 combination from ICC(1,1) 0.942 to 0.980 (% CV: 2.04-4.61). This study demonstrated moderate to high precision for subregional analysis of apparent BMD in the lumbar spine using lateral DXA in vivo. 相似文献
70.
目的:探讨腹腔内注射沙培林增强人腹腔抗癌免疫功能的机制。方法:72例早中期胃肠道肿瘤患者术前48h和24h腹腔内分别注射生理盐水和5KE的沙培林,术中采集腹腔内巨噬细胞,计数并测定乳酸脱氢酶(LDH)和酸性磷酸酶(ACP)的活性,巨噬细胞吞噬活力,一氧化氮(NO)的分泌以及对人胃癌MKN1细胞的细胞毒性进行分析。同时采集大网膜,对大网膜乳斑的数量和面积进行观察。结果:沙培林显著增加腹腔巨噬细胞(PMΦ)的数量和NO的分泌,增强LDH和ACP的活性,吞噬活力,以及抗癌细胞毒性,也显著增加了大网膜乳斑的数量和面积。结论:腹腔内注射沙培林可显著增加人大网膜乳斑的数量和面积,并因此增加PMΦ的数量,增强PMΦ的活性。因而增强了腹腔巨噬细胞的免疫功能。 相似文献