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81.
In Vitro and In Vivo Characterization of MEMS Microneedles 总被引:1,自引:0,他引:1
Transdermal drug delivery TDD systems have many advantages but are conventionally limited by the low permeability of skin. The idea of using microneedles to painlessly penetrate the topmost impermeable stratum corneum has previously been put forward. In this paper, the fabrication of solid and hollow silicon microneedles with straight side-walls and with the following dimensions: 20–100 m in diameter and 100–150 m in length is described. In vitro tests demonstrate that with prior solid microneedle application, transdermal drug transport is significantly increased by 10–20 times, with the degree of enhancement being related to needle diameter. In vivo tests in diabetic animals, however, were unable to demonstrate any delivery of insulin through the hollow microneedles. It is proposed that two factors, microneedle length and tip sharpness, have to be improved for systemic drug delivery to be seen in vivo. 相似文献
82.
苏爱 《中国优生与遗传杂志》2004,12(3):43-44
目的与方法本文对189例自然流产、闭经、发育不全患者进行细胞遗传学检查,结果发现异常核型16例,异常核型涉及1、3、4、5、6、7、8、9、10、 15、X、Y染色体.其中平衡易位10例,性染色体异常3例,大Y染色体3例.结论染色体异常是导致流产、闭经、性发育异常的重要遗传因素,应引起临床医师的高度重视. 相似文献
83.
SARS病人外周血T淋巴细胞的动态变化及其在发病进程和发病机理中的意义 总被引:10,自引:0,他引:10
目的 :通过研究严重急性呼吸综合征 (SevereAcuteRespiratorySyndrome,SARS)患者外周血免疫细胞的动态变化 ,探讨外周血免疫细胞在SARS发病进程中的意义 ,初步探讨SARS的发病机理 ,并为SARS的诊断和治疗提供有力的实验室依据。方法 :回顾性动态观察我院收治的已治愈SARS病例和SARS死亡病例外周血CD4 + 和CD8+ T淋巴细胞 ,评估外周血免疫细胞在SARS发病进程及预后中的作用。实验方法为流式细胞术检测和分析免疫细胞表面特异性荧光抗体标记 ,T细胞表面标志组合为CD3 CD8 CD4 5 CD4。结果 :所有治愈的SARS病人的CD4 + 和CD8+ T淋巴细胞都有不同程度的可逆性下降 ,而所有的死亡病例有不可逆性显著下降 ,直至死亡。T细胞下降程度和维持的时间与病情密切相关。普通型SARS病例最低CD4 + T淋巴细胞数为 30 5± 15 0cells μl(P <0 .0 0 1)、重型为 139± 6 9cells μl(P <0 .0 0 1) ,普通型SARS病例最低CD8+ T淋巴细胞数为 2 2 3± 89cells μl(P <0 .0 0 1)、重型为 171± 92cells μl(P <0 .0 0 1)。所有普通型病例和大部分重型病例T淋巴细胞恢复正常 ,个别重型病例低于正常或接近正常 ,恢复后普通型平均为 991± 2 86cells μl,重型平均为 5 4 5± 2 2 5cells μl。恢复时间有所不同 ,普通型平均为 17± 5天 相似文献
84.
A new haplogroup pattern displayed in Fujian Han in China 总被引:1,自引:0,他引:1
Yu M Zhang Y Xue Y Chen F Wang Q Huang X Wang B Yu Y Liu A Ma L Shi R Lu F Shi Z Zhang Y Cheng W Ai Q Xu F Huang C Chen B Yang H Kang X Sun Y Zhang G Li P Fu S 《Journal of human genetics》2002,47(2):95-98
Human Y-chromosomal binary polymorphisms have been considered to preserve the paternal genetic legacy and provide evidence
on human evolution and the genetic relationships among and demographic history of different populations. To reveal the genetic
origin and immigration of the Fujian Han, 13 binary markers on the Y chromosome were used to screen Fujian Han by allele-specific
polymerase chain reaction. The results indicated that the M9G marker was highly prevalent (96.20%), suggesting a significant genetic drift. In addition, M122C frequency was only 22.78%, and M45A and M103T were default. The distinctive haplogroup frequencies (H1, H5, and H6/7/8) imply that the haplogroup pattern is a relatively ancestral and interim type.
Received: October 13, 2001 / Accepted: December 3, 2001 相似文献
85.
目的 研究岭澳核电站运营后大亚湾核电基地6台机组气态流出物排放对周围陆地环境辐射水平的影响。方法 利用热释光剂量计(TLD)监测广东大亚湾核电基地外围环境辐射水平,在大亚湾核电周围陆地环境布设25个TLD监测点,每3个月左右回收热释光剂量计并测量,长期观测核电周围环境辐射水平变化。结果 2011—2020年大亚湾核电基地外围环境用热释光剂量计测量得到的γ辐射剂量率年均值范围为76.7~207.1 nGy/h、均值为(123.3 ± 5.7) nGy/h,年均值变化相对偏差范围为2%~12%,TLD监测结果、剂量率瞬时测量结果与20世纪国家环保总局组织的调查结果、核电运营前的本底水平一致。结论 不同TLD监测点环境天然辐射水平差异较大,核电站周围50 km范围内的总体环境γ辐射水平没有变化,核电运行气态流出物的释放未对外围环境辐射水平产生累积影响。 相似文献
86.
Junko Ueshima Ryo Momosaki Akio Shimizu Keiko Motokawa Mika Sonoi Yuka Shirai Chiharu Uno Yoji Kokura Midori Shimizu Ai Nishiyama Daisuke Moriyama Kaori Yamamoto Kotomi Sakai 《Nutrients》2021,13(3)
Malnutrition negatively affects the quality of life of patients with dysphagia. Despite the need for nutritional status assessment in patients with dysphagia, standard, effective nutritional assessments are not yet available, and the identification of optimal nutritional assessment items for patients with dysphagia is inadequate. We conducted a scoping review of the use of nutritional assessment items in adult patients with oropharyngeal and esophageal dysphagia. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched to identify articles published in English within the last 30 years. Twenty-two studies met the inclusion criteria. Seven nutritional assessment categories were identified: body mass index (BMI), nutritional screening tool, anthropometric measurements, body composition, dietary assessment, blood biomarkers, and other. BMI and albumin were more commonly assessed in adults. The Global Leadership Initiative on Malnutrition (GLIM), defining new diagnostic criteria for malnutrition, includes the categories of BMI, nutritional screening tool, anthropometric measurements, body composition, and dietary assessment as its required components, but not the blood biomarkers and the “other” categories. We recommend assessing nutritional status, including GLIM criteria, in adult patients with dysphagia. This would standardize nutritional assessments in patients with dysphagia and allow future global comparisons of the prevalence and outcomes of malnutrition, as well as of appropriate interventions. 相似文献
87.
Jian Zhang Ai Zhao Shiyun Lai Qingbin Yuan Xiaojiang Jia Peiyu Wang Yumei Zhang 《Nutrients》2021,13(5)
Our knowledge related to human milk proteins is still limited. The present study determined the changes in multiple human milk proteins during the first six months of lactation, investigated the influencing factors of milk proteins, and explored the impact of milk proteins on infant growth. A total of 105 lactating women and their full-term infants from China were prospectively surveyed in this research. Milk samples were collected at 1–5 days, 8–14 days, 1 month, and 6 months postpartum. Concentrations of total protein and α-lactalbumin were measured in all milk samples, and concentrations of lactoferrin, osteopontin, total casein, β-casein, αs−1 casein, and κ-casein were measured in milk from 51 individuals using ultra performance liquid chromatography coupled with mass spectrometry. The concentration of measured proteins in the milk decreased during the first six months of postpartum (p-trend < 0.001). Maternal age, mode of delivery, maternal education, and income impacted the longitudinal changes in milk proteins (p-interaction < 0.05). Concentrations of αs−1 casein in milk were inversely associated with the weight-for-age Z-scores of the infants (1 m: r −0.29, p 0.038; 6 m: r −0.33, p 0.020). In conclusion, the concentration of proteins in milk decreased over the first six months postpartum, potentially influenced by maternal demographic and delivery factors. Milk protein composition may influence infant weights. 相似文献
88.
检测血管紧张素转化酶在AFP阴性肝癌诊断中的价值 总被引:1,自引:0,他引:1
目的 探讨肝癌患者血清血管紧张素转化酶 (ACE)活性变化对AFP阴性肝癌 (HCC)患者诊断及鉴别诊断的价值。方法 选择经组织学 (肝穿刺 )或影像学确诊的 38例HCC患者 ,2 1例慢性肝炎患者 ,12例肝硬化患者及 2 0例正常健康对照者 ,检测血清AFP含量和ACE活性。结果 与其他良性肝病相比HCC患者血清ACE活性 ( 19.51± 4 .4 6)显著低于慢性肝炎 ( 38.35± 6.34 ,P <0 .0 1)及肝硬化患者 ( 4 7.77± 10 .59,P <0 .0 1) ,并且也低于正常人 ( 30 .0 0± 2 .92 ,P <0 .0 5)。 2 3例AFP阳性 (≥2 0 0mg/L)HCC患者中 ,其ACE活性为 ( 19.15± 4 .2 6) ,与AFP阴性患者比较差异无显著性 (P >0 .0 5)。结论 检测血清ACE活性有助于肝癌 ,尤其是合并肝硬化或AFP阴性的患者的诊断。ACE和AFP联合检测有助于提高肝癌的检出率 相似文献
89.
90.
为研究颈痛宁对无菌性炎症的治疗及毒性作用。建立无菌性炎症试验动物模型。设置颈痛宁、阿斯匹林、醋酸泼尼松、生理盐水等不同对照组,采用光热辐射致痛小鼠痛阈的影响(甩尾法)和对醋酸致痛小鼠镇痛作用(扭体法)的方法进行实验。结果显示:颈痛宁对光热致痛的小鼠痛阈影响,与阿斯匹林、生理盐水比较无明显差异;颈痛宁对醋酸致痛小鼠扭体次数的影响与生理盐水比较有明显差异。说明颈痛宁对软组织无菌性炎症模型有明显的治疗舰艇一定的止痛作用;在治疗软组织损伤退变引发的颈椎病方面具有进一步研究与开发的价值。 相似文献