首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   18314篇
  免费   1360篇
  国内免费   531篇
耳鼻咽喉   7篇
儿科学   682篇
妇产科学   569篇
基础医学   1171篇
口腔科学   82篇
临床医学   1735篇
内科学   7063篇
皮肤病学   82篇
神经病学   446篇
特种医学   215篇
外国民族医学   1篇
外科学   625篇
综合类   2711篇
现状与发展   4篇
预防医学   1216篇
眼科学   62篇
药学   2349篇
  7篇
中国医学   931篇
肿瘤学   247篇
  2024年   61篇
  2023年   229篇
  2022年   433篇
  2021年   556篇
  2020年   495篇
  2019年   499篇
  2018年   534篇
  2017年   561篇
  2016年   581篇
  2015年   557篇
  2014年   935篇
  2013年   1484篇
  2012年   996篇
  2011年   1068篇
  2010年   853篇
  2009年   848篇
  2008年   938篇
  2007年   901篇
  2006年   746篇
  2005年   640篇
  2004年   647篇
  2003年   600篇
  2002年   451篇
  2001年   419篇
  2000年   386篇
  1999年   333篇
  1998年   290篇
  1997年   276篇
  1996年   200篇
  1995年   178篇
  1994年   175篇
  1993年   157篇
  1992年   151篇
  1991年   138篇
  1990年   98篇
  1989年   115篇
  1988年   117篇
  1987年   114篇
  1986年   104篇
  1985年   138篇
  1984年   131篇
  1983年   71篇
  1982年   115篇
  1981年   106篇
  1980年   122篇
  1979年   102篇
  1978年   80篇
  1977年   73篇
  1976年   64篇
  1973年   63篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Background:School-aged children often participate in type 1 diabetes (T1D) self-care tasks. Despite widespread discussion about the importance of developing self-care skills in childhood, few explain how the health care team should assess the skills of children with T1D when performing insulin injections.Objective:We sought to assess content validity evidence in two checklists regarding injection technique performed by children.Methods:Two checklists were designed based on a systematic review of the insulin injection technique. Experts in pediatric diabetes, health literacy, and diabetes education assessed the checklists regarding their clarity, objectivity, and relevance. Content validity was assessed using the content validity ratio (CVR).Results:Eleven providers (72% nurses or physicians, professional experience 19.4 ± 10.1 years, 45% of specialists in endocrinology, and 18% in pediatrics) participated in the assessment. Experts considered items containing the word homogeneity inappropriate. Items related to the needle insertion angle and the skin fold did not reach the CVR critical value. The final version of the checklist for syringe injection comprised 22 items with CVR = 0.91, and the checklist for pen injection comprised 18 items with CVR = 0.87.Conclusions:The checklists presented clear, objective, and relevant content that assesses the skills of children with T1D for insulin injection. The checklists formally present the order of the technique and all the steps for insulin injection and allow a quantitative assessment of the operational skills of children. The developed instruments offer providers the possibility of continuous assessment of the progress of the pediatric clientele until they reach independence in diabetes self-care.  相似文献   
72.
Smart pen technology has evolved over the past decade with new features such as Bluetooth connectivity, bolus dose calculators, and integration with mobile apps and continuous glucose monitors. While similar in appearance to a traditional insulin pen, smart pens have the ability to record and store data of insulin injections. These devices have the potential to transform diabetes management for clinicians, and patients with type 1 and type 2 diabetes on insulin therapy by improving adherence, glycemic control, and addressing barriers to diabetes management. Smart pens can also highlight the relationship between insulin, food, and physical activity, and provide insight into optimizing insulin regimens. Education of clinicians and patients, and more clinical studies showing the benefits of smart pens and cost-effectiveness, are needed.  相似文献   
73.
Abstract

Alginic acid nanoparticles (NPs) containing insulin, with nicotinamide as permeation enhancer were developed for sublingual delivery. The lower concentration of proteolytic enzymes, lower thickness and enhanced retention due to bioadhesive property, were relied on for enhanced insulin absorption. Insulin-loaded NPs were prepared by mild and aqueous based nanoprecipitation process. NPs were negatively charged and had a mean size of ~200?nm with low dispersity index. Insulin loading capacities of >95% suggested a high association of insulin with alginic acid. Fourier Transform Infra-Red Spectroscopy (FTIR) spectra and DSC (Differential Scanning Calorimetry) thermogram of insulin-loaded NPs revealed the association of insulin with alginic acid. Circular dichroism (CD) spectra confirmed conformational stability, while HPLC analysis confirmed chemical stability of insulin in the NPs. Sublingually delivered NPs with nicotinamide exhibited high pharmacological availability (>100%) and bioavailability (>80%) at a dose of 5?IU/kg. The high absolute pharmacological availability of 20.2% and bioavailability of 24.1% in comparison with subcutaneous injection at 1?IU/kg, in the streptozotocin-induced diabetic rat model, suggest the insulin-loaded alginic acid NPs as a promising sublingual delivery system of insulin.  相似文献   
74.
Lately, studies have shown that patients with Parkinson’s disease (PD) report a strong craving for sweets and consume significantly more fast-acting carbohydrates than healthy controls. Consuming food with a high-sugar content is assumed to lead to an increase in insulin concentration, which could positively influence dopamine concentration in the brain and unconsciously be used by patients as kind of “self-medication” to compensate for a lack of dopamine in PD. On the other hand, high-sugar intake could also lead to insulin resistance and diabetes, which is discussed as a causative factor for progressive neurodegeneration in PD. In this critical appraisal, we discuss the role of sugar intake and insulin on dopamine metabolism in patients with PD and how this could influence the potential neurodegeneration mediated by insulin resistance.  相似文献   
75.
Two Caucasian girls, both of normal weight and body mass indices, were diagnosed with type A insulin resistance (IR) in childhood. Case 1 presented with premature adrenarche aged 7 years, then by age 12 years had hirsutism, acne, acanthosis nigricans, and asymptomatic diabetes. Subsequent investigation revealed raised adiponectin (15.3 mg/L) and heterozygous p.Pro1205Leu mutation in the INSR gene encoding the insulin receptor. She experienced postprandial hypoglycaemia on metformin; acarbose was trialled and discontinued aged 16 years, as she became normoglycaemic. Hirsutism was treated with topical eflornithine, oral spironolactone and flutamide, and laser therapy. Unfortunately, diabetes reemerged in young adulthood with obesity. Case 2: during an emergency admission for acute abdominal pain aged 11 years, hyperglycaemia was noted which led to further investigation. An oral glucose tolerance test showed diabetes and ultrasound showed polycystic ovaries. Further investigations revealed raised adiponectin (18 mg/L) and compound heterozygous mutations in the INSR gene: p.Pro1263Ala and p.Ser748Leu (latter probable normal variant). She was treated with metformin and experienced postprandial hypoglycaemia. Symptoms of hyperandrogenism were controlled by flutamide. She maintained a healthy weight and reassessment at young adulthood showed resolution of diabetes. Type A IR may present in childhood with overlapping features of common endocrine entities such as premature adrenarche and polycystic ovarian syndrome. Patients with abnormal glucose tolerance yet normal weight merit screening with adiponectin; raised adiponectin levels prompt insulin receptor mutational analysis. Postprandial hypoglycaemia is characteristic. Management includes optimization of glycaemic control with oral hypoglycaemic agents and maintenance of healthy weight, and controlling the effects of hyperandrogenism.  相似文献   
76.
无沦合并糖尿病与否,多种因素可导致重症患者出现高血糖,高血糖能够增加重症患者的病死率.近来,多项临床研究显示,胰岛素强化治疗可以使血糖严格的控制于正常水平,显著降低各种普通重症患者及诸如心血管、神经.外科等各科重症患者的病死率和医疗费用,并给患芹带来长期的生存获益.虽然强化治疗控制血糖增加了低血糖的发生,但低血糖并未增加患者的病死率.胰岛素强化控制血糖成为重症监护病房中不容忽视的一种重要治疗措施.  相似文献   
77.
目的从PI3K/AKT信号通路研究三七总皂苷(panax notoginseng saponins,PNS)预防糖尿病大血管病变的机制。方法雄性SD大鼠分为对照组、模型组和治疗组,模型组和治疗组大鼠高脂饲料喂养6周后给予链脲佐菌素单次腹腔注射(30 mg·kg-1体质量)建立2型糖尿病模型,成模后治疗组给予PNS灌胃干预(100mg·kg-1体质量)。血糖仪检测大鼠空腹尾静脉血糖(FBG),ELISA法测定血清空腹胰岛素(FINS)和糖化血红蛋白(GHbA1c)水平,苏木素-伊红(HE)染色观察腹主动脉病理形态改变,荧光定量PCR检测腹主动脉标记物MMP2、MMP9、CD34、VEGF及PI3K、AKT mRNA相对表达,Western Blot法观察PI3K和AKT蛋白表达情况。结果模型组和治疗组大鼠在STZ注射造模后,FBG均显著高于对照组(P<0.01和P<0.01),两组间差异无统计学意义(P>0.05)。模型组和治疗组血清INS均显著高于对照组(P<0.01和P<0.01),治疗组INS显著低于模型组(P<0.05)。HE染色显示,与对照组比较,模型组动脉壁变薄,平滑肌细胞增多,排列紊乱,内膜不光滑;治疗组较模型组明显改善。模型组MMP2、MMP9表达较对照组显著上调(P<0.05和P<0.01),治疗组MMP9较模型组显著下调(P<0.01)。模型组CD34、VEGF表达较对照组显著上调(P<0.05和P<0.01),治疗组CD34较模型组显著下调(P<0.05)。模型组大鼠PI3K表达较对照组显著上调(P<0.05),治疗组PI3K表达较模型组显著下调(P<0.05)。模型组PI3K蛋白、p-AKT蛋白表达均显著高于对照组(P<0.01和P<0.01),治疗组PI3K、p-AKT均显著低于对照组(P<0.01和P<0.05),模型组p-AKT/AKT显著高于对照组(P<0.05),治疗组p-AKT/AKT较模型组有显著降低趋势,且与对照组差异无统计学意义。结论PNS可能通过下调PI3K/AKT信号通路预防糖尿病大血管病变。  相似文献   
78.
79.
As HIV-positive women live longer lives, and as testing for HIV becomes more routine, clinicians can expect to see more HIV-positive women in their practices. The need to be aware of management issues particular to this population becomes increasingly important. Metabolic dysregulation is a common, long-term complication associated with HIV and is one of the most difficult to manage. Hormonal contraception also is associated with metabolic dysregulation. As more HIV-positive women choose long-term, reversible contraception, the potential for concomitant and additive side effects, and the need for careful, proactive management strategies to avoid these complications, will become more important. This article reviews research detailing the metabolic dysfunction associated with hormonal contraception and with HIV-seropositivity. It highlights reasons for concern regarding the potential, although as yet theoretical, increased risk for metabolic dysfunction when hormonal contraception is used in the presence of HIV. Suggestions for management strategies for women living with HIV who choose to use hormonal contraception are presented. These strategies should be viewed as suggestions for management until substantitive research becomes available.  相似文献   
80.
AIM: This study aims to investigate the existence of any relationship between homocysteine levels and insulin resistance in Turkish women with polycystic ovary syndrome. METHODS: A case-controlled, cross-sectional, observational study was undertaken in a total of 94 infertile Turkish women who required professional help in the Department of Infertility of Dr Zekai Tahir Burak Women's Health Research and Education Hospital. The correlation between serum homocysteine with age, body mass index, hormone profile, fasting insulin and glucose concentrations and insulin resistance were examined in patients with polycystic ovary syndrome and the results were compared to those of women with normal ovaries, who served as a control group. RESULTS: The mean serum fasting glucose and insulin levels, thus insulin resistance index of women with polycystic ovary syndrome, were significantly higher than those of the control subjects. The mean serum homocysteine levels were significantly higher in women with polycystic ovary syndrome than those in the control group. A positive correlation was detected between the mean homocysteine, the insulin resistance index determined by homeostasis model assessment and the fasting insulin levels in polycystic ovary syndrome patients. CONCLUSIONS: Serum homocysteine levels are elevated in women with polycystic ovary syndrome, and this elevation is associated with the serum insulin level rather than androgen excess. The intense treatment of hyperhomocysteinemia in women with polycystic ovary syndrome might improve reproductive outcome and contribute to protection from cardiovascular risks.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号