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1.
BACKGROUND: Stress can aggravate the allergic inflammation, but determinants of disturbed immune regulation are largely unknown. OBJECTIVE: To determine systemic immunological, local inflammatory and functional airway responses to stress in healthy and atopic individuals. METHODS: Forty-one undergraduate students, 22 with allergy of whom 16 had asthma, and 19 healthy controls, were studied in a low-stress period and in association with a large exam. Subjects completed questionnaires on stress and health behaviours, underwent lung function tests, bronchial methacholine challenge, measurements of exhaled nitric oxide and urine cortisol. Blood cells were phenotyped, and cytokines from mononuclear blood cells were analysed. RESULTS: Perceived stress and anxiety increased in both groups during the exam period while cortisol increased only in the atopy group. Cytokine production decreased broadly in response to stress in both groups, which was paralleled by an increase in the proportion of regulatory T cells (CD4(+)CD45RO(+)CD25(bright)). Interestingly, atopic individuals, but not controls, reacted with a decreased T-helper type 1/T-helper type 2 (Th1/Th2) ratio and a decrease in natural killer (NK) cell numbers in response to stress. In control subjects only, exhaled nitric oxide decreased and forced expiratory volume in one second increased during stress. CONCLUSION: Atopic and non-atopic subjects shared some immune changes in response to stress, such as a dramatic decline in cytokines and an increase in the number of regulatory T cells in peripheral blood. However, other stress-induced immune changes were unique to atopic individuals, such as a skewed Th1/Th2 ratio and reduced NK cell numbers, indicating that some pathogenic mechanisms in atopics may be more strongly affected by stress than others.  相似文献   
2.
缺血性脑血管疾病是一个非常复杂的病理生理过程 ,是多种机制共同作用的结果。本文从针刺对实验性脑缺血在脑组织形态学改变、血液流变学、脑微循环等方面的研究进展作一综述。  相似文献   
3.
Launonen V 《Human mutation》2005,26(4):291-297
The human LKB gene (official HUGO symbol, STK11) encodes a serine/threonine protein kinase that is defective in patients with Peutz-Jeghers syndrome (PJS). PJS is an autosomal dominantly inherited syndrome characterized by hamartomatous polyposis of the gastrointestinal tract and mucocutaneous pigmentation. To date, 145 different germline LKB1 mutations have been reported. The majority of the mutations lead to a truncated protein product. One mutational hotspot has been observed. A 1-bp deletion and a 1-bp insertion at the mononucleotide repeat (C6 repeat, c.837-c.842) between the codons 279-281 have been found in six and seven unrelated PJS families, respectively. However, these mutations account only for approximately 7% of all mutations identified in the PJS families (13/193). A review of the literature provides a total of 40 different somatic LKB1 mutations in 41 sporadic tumors and seven cancer cell lines. Mutations occur particularly in lung and colorectal cancer. Most of the somatic LKB1 mutations result in truncation of the protein. A mutational hotspot seems to be a C6 repeat accounting for 12.5% of all somatic mutations (6/48). These results are concordant with the germline mutation spectrum. However, the proportion of the missense mutations seems to be higher among the somatic mutations (45%) than among the germline mutations (21%), and only seven of the mutations are exactly the same in both of the mutation types.  相似文献   
4.

Although adolescents living on the street tend to have unprotected sex with many partners and substance abuse, little is known about this reality in Brazil. To estimate the prevalence and factors associated with risky sexual behavior among children and adolescents living on the street in Porto Alegre and Rio Grande. A cross-sectional study was carried out using the Respondent-Driven Sampling (RDS) sampling method to quickly and efficiently access populations of difficult access. Poisson regression with robust adjustment of variance was used in the multivariate analysis. The sample consisted of 231 participants aged 10–21 years. Most were male and aged 16- 21 years. More than half (66.7%) of the respondents did not have a school bond, and 64.5% did not live with the family. Half of the sample had been living on the street for at least four years, spending 15 h or more on the street. Most (86.6%) responded that they had already used illicit drugs in their lives, and unprotected sex prevalence was 61.9%. The variables independently associated with unprotected sex were years living on the street, hours spent on the street, having a steady partner, illicit drug use, and sexual intercourse without a condom under the influence of drugs. The high prevalence of unprotected sex points to the need for intervention policies for this population to prevent the main risk factors.

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5.
Objective.The correlation betweenp53tumor suppressor gene mutations and the presence of high-risk human papillomavirus (HPV) DNA with thein vitroradiosensitivity of gynecological malignancies was studied in 26 cell lines derived from gynecological cancers of 23 patients.Methods.Comparison of the intrinsic radiosensitivity was performed with mean inactivation dose (D?) determined with the 96-well plate clonogenic assay.p53mutations were investigated with polymerase chain reaction and single-strand conformation polymorphism (PCR–SSCP) analysis and direct DNA sequencing, and the presence of HPV DNA was studied with PCR using HPV consensus primers.Results. p53mutations were found in 6 of 10 vulvar squamous cell carcinoma (SCC) lines. Nine vulvar and 1 vaginal SCC cell lines were HPV DNA negative and 1 vulvar cell line was HPV 16 positive. All 4 cervical SCC lines were HPV positive and possessed the wild-typep53.Three cell lines expressed HPV 16 and 1 HPV 68. Among 10 endometrial cancer cell lines, 2 cell lines with mutantp53and 1 HPV 16 positive cell line were found. No correlation could be demonstrated between inactivation of thep53gene and radiosensitivityin vitro;the cell lines were evaluated as one group or according to their anatomical origin or histology.Conclusion.Our results indicate that inactivation of thep53gene through mutation or binding with HPV DNA does not increase the resistance of gynecological malignancies to ionizing radiationin vitro.  相似文献   
6.
观察利用微信干预增加青光眼患者体力活动的效果。方法:前瞻性随机对照研究。选择2018年 6-12月于温州医科大学附属眼视光医院门诊确诊的青光眼患者102例作为研究对象。利用Excel生成的随机数随机分为对照组和干预组。对照组患者仅在门诊入组时进行运动宣教,并告知其可增加每天的运动步数;干预组患者入组时进行运动宣教,告知其可增加每天的运动步数的同时,加入微信群进行运动提醒干预。所有患者均需利用运动监测仪器完成基线1周和随访1个月的体力活动监测。采用卡方检验、独立样本t检验、Mann-Whitney U检验、配对t检验及Wilcoxon符号秩检验进行数据分析。结果:排除30例基线运动量较大(步数>12 000步/d)、依从性不好及其他原因失访的患者,最终纳入72例(对照组42例,干预组30例)。干预组患者干预后的步数(t=4.94,P<0.001),运动消耗的卡路里(Z=-2.87,P=0.004),代谢当量(Z=-3.30,P=0.001),中等强度体力活动时间(Z=-2.89, P=0.004),高强度体力活动时间(t=2.57,P=0.016)及中高强度体力活动时间(Z=-3.01,P=0.003)均较基线增加;轻度体力活动时间(t=-2.14,P=0.041)和久坐静止不动次数较干预前减少(t=-2.76, P=0.022)。对照组随访的步数也较基线增加(t=3.29,P<0.001),轻度体力活动时间较基线减少(t=-2.57,P=0.014)。另外,干预组的高强度体力活动时间增加量(随访-基线)(Z=-3.04,P=0.002)和超高强度体力活动时间增加量(Z=-2.06,P=0.040)明显高于对照组,差异均有统计学意义。结论:微信干预可以增加青光眼患者的每天运动步数和中高强度体力活动时间,减少患者的轻度体力活动时间和久坐静止次数。  相似文献   
7.
8.
The past 2 decades have seen a considerable global increase in cardiovascular disease, with hypertension remaining by far the most common. More than one-third of adults in Africa are hypertensive; as in the urban populations of most developing countries. Being a condition that occurs with relatively few symptoms, hypertension remains underdetected in many countries; especially in developing countries where routine screening at any point of health care is grossly underutilized. Because hypertension is directly related to cardiovascular disease, this has led to hypertension being the leading cause of adverse cardiovascular outcomes, as a result of patients living, often unknowingly, with uncontrolled hypertension for prolonged periods of time. In Africa, hypertension is the leading cause of heart failure; whereas at global levels, hypertension is responsible for more than half of deaths from stroke, just less than half of deaths from coronary artery disease, and for more than one-tenth of all global deaths. In this review, we discuss the escalating occurrence of hypertension in developing countries, before exploring the strengths and weaknesses of different measures to control hypertension, and the challenges of adopting these measures in developing countries. On a broad level, these include steps to curb the ripple effect of urbanization on the health and disease profile of developing societies, and suggestions to improve loopholes in various aspects of health care delivery that affect surveillance and management of hypertension. Furthermore, we consider how the industrial sectors' contributions toward the burden of hypertension can also be the source of the solution.  相似文献   
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10.
Abstract Background: We studied the associations of clustering of metabolic risk factors with plasma levels of alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) in healthy prepubertal children. Methods: The subjects were a representative population sample of 492 children 6-8 years of age. We assessed body fat percentage (dual-energy X-ray absorptiometry), body mass index, waist circumference, systolic and diastolic blood pressure, glucose, insulin, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, ALT, GGT, and high-sensitivity C-reactive protein (hsCRP) and calculated a continuous metabolic syndrome score variable. We also used factor analysis to examine whether high-normal liver enzymes are a feature of metabolic syndrome among children. Results: Children with overweight or obesity, defined by International Obesity Task Force (IOTF) criteria, had a 2.1-times higher risk of having ALT and a 4.5-times higher risk of having GGT in the highest fifth of its distribution than normal weight children. Children in the highest sex-specific third of metabolic syndrome score, body fat percentage, waist circumference, and insulin had a two to three times higher risk of being in the highest fifth of ALT and GGT. Moreover, children in the highest third of glucose and hsCRP had a 2.5-fold risk of being in the highest fifth of GGT. First-order factor analysis yielded three factors; the first included insulin, glucose, and triglycerides; the second waist circumference, insulin, GGT, and hsCRP; and the third HDL-C, triglycerides, waist circumference, and insulin. Second-order factor analysis yielded a single metabolic syndrome factor, explaining 64.1% of the variance. Conclusions: Clustering of metabolic risk factors, particularly excess body fat, is associated with high-normal levels of ALT and GGT in prepubertal children. High-normal levels of liver enzymes, especially GGT, and systemic low-grade inflammation could be considered features of metabolic syndrome among children. Subtle changes in liver function may play an important role in the pathogenesis of metabolic syndrome beginning in childhood.  相似文献   
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