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1.
The aetiology of Klinefelter's Syndrome is not known. The causative factor(s) must explain the hypogonadism, low androgen levels, the disordered carbohydrate metabolism and the commonly associated psychiatric conditions. A biotin deficient/dependent state can account for the above. A biotin deficient Klinefelter's Syndrome patients with the above is described. The possible role of biotin in the primary, secondary and tertiary prevention of Klinefelter's Syndrome needs further research.  相似文献   
2.
Final-year undergraduate medical students were given a questionnaire on the gross anatomy curriculum they had experienced in their first year at medical school 5 years earlier. They were asked to evaluate the relevance of the dissection course, lectures and seminars in gross anatomy for clinical courses, clerkships, and everyday practical work on the ward. About two-thirds of the students found the time spent on 10 different regions in anatomy to be adequate, and a considerable number of students would have liked even more details. The vast majority expressed a wish to repeat topographical anatomy during their clinical teaching. Furthermore, ~75% of the students showed interest in short, specialized dissection courses during the clinical curriculum. Medical students just before graduation ranked gross anatomy with the dissection course and integrated clinical topics as a keystone for their clinical courses. The results of such surveys should be taken into consideration when discussing modification to teaching gross anatomy or arguing about a balanced dissection course. © 1993 Wiley-Liss, Inc.  相似文献   
3.
药物与血浆蛋白结合的药理学基础及其研究进展   总被引:4,自引:0,他引:4  
体内各种因素引起的药物与血浆蛋白结合的改变,可能导致相应的药代动力学参数变化。本文综述了有关药物 血浆蛋白结合的基础理论和研究方法进展,及其与药代动力学和药效相关性的理论阐述,并运用药理学相关基础理论对其临床意义进行了深入的探讨,总结了在常规的药物实践中如何评价药物的游离浓度监测和血浆蛋白结合的药效和临床相关性研究。  相似文献   
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Optimization of operating and design parameters is needed for the greater application to achieve higher quality, performance, and minimum cost. The paper mainly concentrates on, the optimization of process parameters influencing the deflouridation of water by Analysis of mean (ANOM) approach. The current work mainly aims at the utilization of the Taguchi approach to optimize influencing operating parameters for maximizing the removal of fluoride under batch experimental studies by using biosorbent developed from Saccharum spontaneum, weed plant. The optimum conditions were found at pH 7, sorbate content 5 mg/L, period of contact 120 min, sorbent dosage 10 g/L, and temperature 30 °C. The percent part of various process parameters is obtained in the successive sequence pH 56.21% > initial concentration of adsorbate 33.94% > biosorbent dose 5.49% > contact time 3.35% > temperature 1.01%. The equilibrium study indicates fluoride sorption on Saccharum spontaneum adsorbent fulfill the Langmuir model with parameters ‘a' and ‘b' determined as 1.617 mg/g and 0.473 L/mg. The kinetic study with sorption data suggested the Pseudo-second order kinetic model as best fitting with kinetic rate k2 0.218 g/mg min. The thermodynamic analysis suggested a spontaneous and endothermic nature (ΔH = 16.268 kJ/mol). Characterization of adsorbent was done using BET, SEM, and also by the determination of textual properties. Regeneration of the biosorbent is done for three cycles and is used for fluoride removal.  相似文献   
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Introduction: Drosophila melanogaster offers a powerful expedient and economical system with facile genetics. Because of the high sequence and functional conservation with human disease-associated genes, it has been cardinal in deciphering disease mechanisms at the genetic and molecular level. Drosophila are amenable to and respond well to pharmaceutical treatment which coupled to their genetic tractability has led to discovery, repositioning, and validation of a number of compounds.

Areas covered: This review summarizes the generation of fly models of human diseases, their advantages and use in elucidation of human disease mechanisms. Representative studies provide examples of the utility of this system in modeling diseases and the discovery, repositioning and testing on pharmaceuticals to ameliorate them.

Expert opinion: Drosophila offers a facile and economical whole animal system with many homologous organs to humans, high functional conservation and established methods of generating and validating human disease models. Nevertheless, it remains relatively underused as a drug discovery tool probably because its relevance to mammalian systems remains under question. However, recent exciting success stories using Drosophila disease models for drug screening, repositioning and validation strongly suggest that fly models should figure prominently in the drug discovery pipeline from bench to bedside.  相似文献   

8.
The gastrointestinal tract of vertebrate species is a rich source of extrapineal melatonin. The concentration of melatonin in the gastrointestinal tissues surpasses blood levels by 10–100 times and there is at least 400× more melatonin in the gastrointestinal tract than in the pineal gland. The gastrointestinal tract contributes significantly to circulating concentrations of melatonin, especially during the daytime and melatonin may serve as an endocrine, paracrine, or autocrine hormone influencing the regeneration and function of epithelium, enhancing the immune system of the gut, and reducing the tone of gastrointestinal muscles. As binding sites for melatonin exhibit circadian variation in various species, it has been hypothesized that some melatonin found in the gastrointestinal tract might be of pineal origin. Unlike the photoperiodically regulated production of melatonin in the pineal, the release of gastrointestinal melatonin seems to be related to the periodicity of food intake. Phylogenetically, melatonin and its binding sites were detected in the gastrointestinal tract of lower vertebrates, birds, and mammals. Melatonin was found also in large quantities in the embryonic tissue of the mammalian and avian gastrointestinal tract. Food intake and, paradoxically, also long-term food deprivation resulted in an increase of tissue and plasma concentrations of melatonin. Melatonin release may have a direct effect on many gastrointestinal tissues but may also well influence the digestive tract indirectly, via the central nervous system and the sympathetic and parasympathetic nerves. Melatonin prevents ulcerations of gastrointestinal mucosa by an antioxidant action, reduction of secretion of hydrochloric acid, stimulation of the immune system, fostering epithelial regeneration, and increasing microcirculation. Because of its unique properties, melatonin could be considered for prevention or treatment of colorectal cancer, ulcerative colitis, gastric ulcers, irritable bowel syndrome, and childhood colic.  相似文献   
9.
分析血清电解质、肌酸激酶同工酶(CKBB)及血乳酸水平与新生儿缺氧缺血性脑病严重程度的相关性。80例缺氧缺血性脑病患儿中轻度患儿27例、中度患儿26例、重度患儿27例。以本院同期健康的足月新生儿60例为对照组。结果显示与对照组新生儿比较,观察组新生儿氯离子及钙离子水平明显降低(P<0.05),CKBB和血乳酸水平明显升高(P<0.05);重度患儿的氯离子及钙离子水平明显低于中度患儿和轻度患儿(P<0.05),CKBB和血乳酸水平明显高于中度患儿和轻度患儿(P<0.05);血清中氯离子和钙离子与缺氧缺血性脑病严重程度呈现负相关性(P<0.05),但CKBB和血乳酸与缺氧缺血性脑病严重程度呈明显的正相关性(P<0.05)。结果说明血清氯离子和钙离子、CKBB及血乳酸水平与新生儿缺氧缺血性脑病严重程度呈明显的相关性。  相似文献   
10.
目的 探索藏族医(简称藏医)“方-药-量-性”关系复杂而共性关联突出,难以揭示隐形特异性藏医药临床用药规律等科学问题的解决方法。方法 该研究基于属性偏序结构、“味性化味”矢量结构模型、聚类分析等方法,分析《中华人民共和国卫生部药品标准藏药(第一册)》收载184首藏医临床常用方剂的“方-药-量-性”关系。结果 方-药关系分析发现诃子、红花等11个最大共有属性组方,是分类配伍的关键组方,可以有效分类治疗隆病、赤巴病、血热病等8类方剂,在方剂中三果汤散、六味良药散等调节三因和辅助脏腑功能类组方药物的共有性最强。药-量关系分析发现,诃子、红花、石榴子、余甘子等用量最高,表明这些组方药物一般以君药形式入药,而豆蔻、草果等六味良药散组方药物虽频次较高,但剂量较低,主要起着调节方剂整体药性和保护脏腑的作用,而麝香、牛黄、渣驯等藏医特效药物,频次虽高但剂量很低,具有增强药性,引药患处的作用。量-性关系分析发现属于凉性方剂较多,占75.6%,发现有67首方剂因其组方剂量不同而产生药性与功效不相符的现象。结论 藏医方剂中存在很多共性组方和共性用法,如不对这些共性关联加以处理,会出现任何疾病均以这些共性关联为核心的结果,却无法解开隐性的关键因素。因此,在“方-药-量-性”等多维层面同时注重敏感性和特异性规律,才能更有效地揭示藏医临床用药思想。  相似文献   
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