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11.
化学染发剂和冷烫精的毒性及对人体健康影响的调查研究 总被引:7,自引:1,他引:6
本文通过化学染发剂和冷烫精对大白鼠骨髓多染红细胞,毛囊细胞的微核实验及人群健康影响调查,结果表明化学染发剂,冷烫清具有较强致突变作用,两者同时使用致突变明显增强,并提出研制高效无毒染发剂和加强防护的重要性。 相似文献
12.
LYNDA E ALBERTYN 《Journal of Medical Imaging and Radiation Oncology》1992,36(1):17-22
Both systemic and local therapy, for conditions of the breast and unrelated to it, may produce manuno-graphic changes. Some of these are characteristic, such as the pattern of scarring seen in reduction mammo-plasty. In many other instances, however, the changes produced overlap features commonly seen in malignancy. A knowledge of the timing, natural history and spectrum of these changes will aid mammographic interpretation. 相似文献
13.
Stuart A. Batterman Alfred Franzblau Nanzheng Zhou 《International archives of occupational and environmental health》1996,68(4):268-274
Dermal exposures of methanol were administered in a clinical study designed to compare several biological indicators. Four
subjects were exposed in five exposure sessions of varying length. In each session, a sequence of measurements of methanol
concentrations in blood, breath, and headspace samples of air at exposed and unexposed skin were collected before and after
dermal exposures. Skin headspace samples, collected in gas sampling bags, were designed to reflect equilibrium skin: air partitioning.
At exposed skin, headspace samples were highly elevated for at least 8 h following exposure, indicating the presence of a
methanol reservoir in skin. After exposure, methanol concentrations at exposed skin showed a rapid initial decline, then a
slower first-order decrease. Methanol concentrations were clearly detectable in headspace samples at unexposed skin. Substantial
transfer from exposed skin occurred due to mechanical contact and washing. When transfer was restricted, surface concentrations
at unexposed skin were similar to levels in breath and were strongly correlated to methanol concentrations in blood. While
results are preliminary due to the small sample sizes and several unresolved experimental issues, the simple, rapid, and noninvasive
skin headspace measurements appear useful as a biological exposure indicator that clearly shows the presence and site of a
dermal exposure, and measurements at unexposed skin reflect concentrations in blood.
Received: 14 March 1995/Accepted: 3 November 1995 相似文献
14.
15.
Porcine models have been used extensively for skin flap research because of the established similarity between the cutaneous
blood supply of the swine and humans. The Yucatan minipig provides an excellent model for researching the properties of random
cutaneous flaps, offering several advantages over other breeds of swine. In this study, a total of 67 random cutaneous dorsal
flank flaps measuring 4 × 14 cm were raised on nine Yucatan minipigs. The mean survival length (10.03 ± 1.60 cm) of the nondelayed
flaps was greater than others reported in the literature. The well-defined plane between the subcutaneous tissue and the panniculus
carnosus facilitated flap elevation consistently above the level of the panniculus carnosus thereby ensuring the creation
of a true random cutaneous flap. Furthermore, the hairless nature of the skin, particularly beneficial in studying chemical
peels, permits easy visualization and monitoring of any external skin changes. These advantages make the Yucatan minipig a
more desirable alternative to other breeds of swine for use in skin flap research. 相似文献
16.
目的:报告了因汽车安全气囊造成的眼外伤及化学性烧伤。希望引起眼科同仁的高度重视.方法:4例病人均是进口高档小卧车,在发生碰撞时因汽车安全气囊高速膨胀打开及气囊破裂所致的眼损伤及化学烧伤.分析了汽车型号及种类,事故发生时的速度,眼损伤的类型和视力情况.结果:第一例病人为碱性化学性角膜炎伴虹膜根部离断及瞳孔括约肌破裂而造成瞳孔扩大;第二例病人为近视镜片致角巩膜板层撕裂伤;第三例病人为广泛角膜擦伤伴前房出血;第四例病人为视网膜水肿出血伴后极部脉络膜裂伤.结论:安全气囊能保护生命降低致伤率,但因气囊的冲击力量引起的机械损伤和气囊中强碱性气体导致的化学烧伤更要引起国内眼科医生的注意. 相似文献
17.
云芝糖肽的结构组成分析 总被引:4,自引:0,他引:4
目的:对云芝糖肽的结构与组成进行研究.方法:采用还原衍生化气相色谱,紫外、核磁、高碘酸氧化、Smith降解、琼脂糖凝胶电泳等方法.结果:云芝糖肽由葡萄糖、半乳糖、岩藻糖、甘露糖、木糖和鼠李糖组成,具有α,β型糖苷键,连接方式有(1→4)、(1→6)两种,含有结合态蛋白,糖肽键类型初步确定为N-连接.结论:首次对云芝糖肽的化学结构与组成进行了较为细致的研究. 相似文献
18.
云南阳春砂仁的质量与生态环境关系的探讨 总被引:7,自引:0,他引:7
当前云南阳春砂仁产量,占全国总产量的65.5%,商品有左右全国砂仁市场之势。经调查云南产区生态环境较原产区广东阳春县为优,故表现出植株生长较高,果实较大,每室籽粒数较多等性状特征之差,这些差异并非是物种的变异,而是生态环境较好所致。从两地商品中的精油成分和微量元素分析结果也基本一致,认为影响云南阳春砂仁质量的酸味,两地商品均有,并都来源于假种皮,只不过云南商品果实较大,假种皮较厚,总酸含量较高,但是总酸均为无毒副作用的低分子有机酸,不影响砂仁的质量。因此我们认为云南引种区的阳春砂仁质量,与广东原产区的阳春砂仁质量应基本一致。 相似文献
19.
D Evison R F R Brown P Rice 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(10):1087-1093
The chemical warfare agent, sulphur mustard (SM), is a potent blistering agent in man. Skin exposure can produce partial-thickness burns which take up to three months to heal. The aim of this study was to investigate the use of early laser ablation as a means of accelerating this exceptionally slow rate of healing. Four circular partial-thickness SM burns were induced on the dorsum of nine large white pigs (under general anaesthesia). At 72 h post-exposure, three burns per animal were ablated with a single pass of an UltraPulse 5000C CO(2) laser, at a fluence of 5-6 J cm(-2). All the burns were dressed with silver sulphadiazine and a semi-occlusive dressing. At one, two and three weeks post-surgery three animals were culled and all lesions excised for histological analysis. Burn depth was confirmed and measurements of the radii of regenerative epithelium were performed allowing the area of the zone of re-epithelialisation in each lesion to be calculated. Laser-treated lesions showed a significant increase (350%) in healing rates compared to controls (p<0.005). At two weeks, the laser-treated sites were 95% healed in comparison with control sites (28% healed). These data suggest that laser ablation may be effective in the treatment of partial-thickness SM-induced skin injury. 相似文献
20.