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   272篇
  免费   10篇
儿科学   19篇
妇产科学   4篇
基础医学   21篇
口腔科学   8篇
临床医学   19篇
内科学   98篇
皮肤病学   19篇
神经病学   3篇
特种医学   19篇
外科学   36篇
综合类   1篇
预防医学   6篇
眼科学   23篇
肿瘤学   6篇
  2023年   4篇
  2022年   8篇
  2021年   12篇
  2020年   8篇
  2019年   10篇
  2018年   8篇
  2017年   6篇
  2016年   9篇
  2015年   5篇
  2014年   12篇
  2013年   12篇
  2012年   13篇
  2011年   22篇
  2010年   27篇
  2009年   16篇
  2008年   25篇
  2007年   21篇
  2006年   14篇
  2005年   17篇
  2004年   14篇
  2003年   8篇
  2002年   2篇
  2001年   2篇
  2000年   2篇
  1998年   2篇
  1996年   1篇
  1995年   2篇
排序方式: 共有282条查询结果,搜索用时 15 毫秒
1.
BACKGROUND: Despite plenty of research, the cause of recurrent aphthous stomatitis (RAS) remains obscure. It has been proposed that, the aetiological factors such as local trauma, smoking, vitamin deficiencies and viral infections lead to aphthae formation via final common pathway based on increased oxidative stress. The aim of this investigation was to evaluate the antioxidant enzyme superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) alterations in plasma and saliva, and in addition uric acid (UA) in saliva, in patients with RAS and healthy controls. METHODS: Thirty-two patients with RAS and 30 healthy controls were included into the study. The SOD, CAT, GSHPx and UA levels were measured in plasma and saliva in study and control groups. RESULTS: In the RAS group, although the mean SOD (P<0.001) and CAT (P<0.05) levels of plasma were lower, GSHPx (P<0.001) levels were higher than control group. The salivary concentrations of the SOD (P<0.001), CAT (P<0.05) and GSHPx (P<0.001) in RAS group were entirely opposite to plasma concentrations. UA were not significant between RAS group and controls. CONCLUSION: Since we found salivary SOD and CAT levels were high whereas plasma levels were low, it has been thought that, salivary defence mechanisms via antioxidant agents may be stimulated against to the ulcerous lesion. We consider that the organism might mobilize the antioxidant potential to the sites where they were needed. At this point, decrease of SOD and CAT levels in the plasma may be related to this shift. It is also thought that GSHPx secretion in the saliva may also be increased but the increase in its turnover may be responsible for the diminished activity.  相似文献   
2.
Little information exists regarding the efficacy, modifiers, and outcomes of anemia management in children with CKD or ESRD. We assessed practices, effectors, and outcomes of anemia management in 1394 pediatric patients undergoing peritoneal dialysis (PD) who were prospectively followed in 30 countries. We noted that 25% of patients had hemoglobin levels below target (<10 g/dl or <9.5 g/dl in children older or younger than 2 years, respectively), with significant regional variation; levels were highest in North America and Europe and lowest in Asia and Turkey. Low hemoglobin levels were associated with low urine output, low serum albumin, high parathyroid hormone, high ferritin, and the use of bioincompatible PD fluid. Erythropoiesis-stimulating agents (ESAs) were prescribed to 92% of patients, and neither the type of ESA nor the dosing interval appeared to affect efficacy. The weekly ESA dose inversely correlated with age when scaled to weight but did not correlate with age when normalized to body surface area. ESA sensitivity was positively associated with residual diuresis and serum albumin and inversely associated with serum parathyroid hormone and ferritin. The prevalence of hypertension and left ventricular hypertrophy increased with the degree of anemia. Patient survival was positively associated with achieved hemoglobin and serum albumin and was inversely associated with ESA dose. In conclusion, control of anemia in children receiving long-term PD varies by region. ESA requirements are independent of age when dose is scaled to body surface area, and ESA resistance is associated with inflammation, fluid retention, and hyperparathyroidism. Anemia and high ESA dose requirements independently predict mortality.Almost three decades after the advent of recombinant erythropoietin, the management of renal anemia has become a recent focus of attention and changing paradigms. Whereas correction of hemoglobin (Hb) levels to near-normal has previously been recommended on the basis of association studies linking more severe anemia to morbidity and mortality with dialysis,13 interventional clinical trials consistently demonstrate that near-normalization of Hb increases the risk of vascular events and mortality in adults receiving maintenance hemodialysis and in those with CKD who are not undergoing dialysis.46 This has prompted ongoing reevaluation and revisions of treatment targets in patients exposed to erythropoiesis-stimulating agents (ESAs).7The appropriateness of applying treatment recommendations established in adult hemodialysis populations at high cardiovascular risk and adults with CKD to children undergoing dialysis is questionable because cardiovascular events are far less common in children with CKD. Furthermore, two thirds of children requiring dialysis initially opt for peritoneal dialysis (PD), and there are no systematic studies in the adult PD population to inform the optimal Hb target range in these patients. The risk profile of patients receiving PD may differ from that of the hemodialysis setting because of the absence of dialysis-induced intermittent hemoconcentration and lack of contact activation of the complement and coagulation systems.Further aspects to consider in pediatric anemia management are the greater physical activity of children and the need for optimal cognitive functioning at school.8,9 The significant physiologic variation of the normal Hb range with age10 and the relative ESA sensitivity that reportedly increases with age during early childhood are also noteworthy.11The registry of the International Pediatric Peritoneal Dialysis Network (IPPN) prospectively collects detailed clinical, biochemical, dialysis, and medication-related information (including ESA types and doses and modalities of iron supplementation) from a substantial number of children undergoing long-term PD around the world. In-depth analysis of this unique database has allowed us to (1) gain insight into the demographic characteristics of renal anemia and its treatment in the pediatric PD population worldwide, (2) explore the relationship between ESA dose requirements and body dimensions, (3) identify factors contributing to ESA resistance in children, and (4) associate anemia control with patient outcomes.  相似文献   
3.

Background

Lip augmentation and changing contour lines have become more popular ways of improving the appearance. However, validated measures of lip fullness for quantification of outcomes are needed; ethnic background and personal goals can optimise outcomes while tailoring lip enhancement treatment to each individual’s anatomy. The aim of this study is to analyse the morphological features of the lip in detail and to clarify the objective parameters in related with the subjective ones regarding the lip augmentation and lip reconstruction.

Methods

Standard photographs of the lips of 200 young Anatolian adults were calculated with linear and angular components. The features of the lower third of the face were analysed with the software program. Linear analyses (heights of the upper lip, the upper vermilion, the lower lip height, the lower vermillion and the chin height) and angular analyses (the upper lip, the lower lip, the apex and Cupid’s bow angles) were measured as reference points. The lip shape was classified into five groups: thin, very thin, medium, full and very full.

Results

The lower third of the face was divided into three segments (Sn–Sto, Sm–Me and Sto–Sm), and the largest portion of the lower face was occupied by the chin and the smallest by the lower lip height in both genders. The upper vermilion height was 8.07?±?1.8 mm in males and 7.08?±?1.5 mm in females. The lower vermilion height was 10.1?±?2.4 mm in males and 9.7?±?1.9 mm in females. The upper lip angle was calculated as 30.3?±?9.6° in males and 24.2?±?6.2°mm in females. The lower lip angle was calculated as 38.3?±?9.7° in males and 36.5?±?6.4° in females. Meanwhile, the angular measurements of Cupid’s bow (i.e., the apex and the central angle of Cupid’s bow) were smaller in men than in women. When the lip was analyzed, the medium and full types in upper and lower lips accounted for substantial fractions in men, whereas medium and thin types were predominant also in women.

Conclusions

With the help of certain software, this research has made possible to define the best cosmetical redesign solution of lip construction and augmentation with a natural appearance for the patient.Level of Evidence: Level III, diagnostic study.
  相似文献   
4.
Breast cancer is the most frequent cancer among females and also a leading cause of cancer related mortality worldwide. A multimodality treatment approach may be utilized for optimal management of patients with combinations of surgery, radiation therapy (RT) and systemic treatment. RT composes an integral part of breast conserving treatment, and is typically used after breast conserving surgery to improve local control. Recent years have witnessed significant improvements in the discipline of radiation oncology which allow for more focused and precise treatment delivery. Adaptive radiation therapy (ART) is among the most important RT techniques which may be utilized for redesigning of treatment plans to account for dynamic changes in tumor size and anatomy during the course of irradiation. In the context of breast cancer, ART may serve as an excellent tool for patients receiving breast irradiation followed by a sequential boost to the tumor bed. Primary benefits of ART include more precise boost localization and potential for improved normal tissue sparing with adapted boost target volumes particularly in the setting of seroma reduction during the course of irradiation. Herein, we provide a concise review of ART for breast cancer in light of the literature.  相似文献   
5.
Our aim was to determine whether N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and cardiac troponin I (cTnI) levels are valuable for predicting prognosis in patients with infective endocarditis (IE). We analyzed measured plasma NT-pro-BNP levels at admission in 45 patients with definite IE. The primary end point was early surgery or in-hospital death. The other data recorded were baseline clinical, echocardiographic, and laboratory parameters. Thirty patients underwent early surgery, and 9 died in hospital. Univariate analysis revealed that log NT-pro-BNP, cTnI > or =0.03 ng/ml, New York Heart Association functional class III to IV symptoms, left atrial diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter, and severe valvular regurgitation were associated with increased risk of reaching the primary end point. Cox proportional hazard regression analysis identified log NT-pro-BNP (hazard ratio 1.5; 95% confidence interval 1.2 to 1.9, p <0.001) as the only independent predictor of the primary end point. The log NT-pro-BNP cut-off value with the highest sensitivity (97%) and specificity (92%) for predicting primary end point was 7.2 (1,500 pg/ml). Patients with NT-pro-BNP level > or =1,500 pg/ml had significantly lower event-free survival than others. In conclusion, admission NT-pro-BNP is of prognostic value in patients with IE. The combination of admission NT-pro-BNP and cTnI levels appears to have even greater value for risk stratification in this patient group.  相似文献   
6.
Background: Over the last three decades the prevalence of overweight and obesity has increased dramatically among children and adolescents worldwide. As the results of animal and human studies suggest that a diet rich in fructose may be a risk factor for the development of overweight, the aim of the pilot study was to evaluate if a dietary counseling aimed at a moderate reduction of dietary fructose intake (?50% in comparison to intake at baseline) has a positive effect on the body mass index (BMI) of overweight and obese children. Methods: Fifteen overweight or obese children aged 5–8 years were included into the 3 month dietary intervention study. At baseline and after 4 and 8 weeks children and their parents were trained to reduce fructose in the children's diet. Anthropometric parameters for calculating BMI and BMI standard deviation scores (BMI‐SDS) as well as nutritional intake were assessed at baseline, after the 12‐week intervention and after 12 week of follow up. Results: After the 12‐week intervention children had significantly reduced their total energy, fructose, sucrose and glucose intake. BMI and BMI‐SDS were significantly reduced by 0.68 kg/m2 and 0.21, respectively, at the end of the intervention. At follow up, the BMI‐SDS was significantly lower in comparison to baseline while the BMI was only decreased by trend (P= 0.08). Conclusions: The results of our pilot study indicate that counseling aimed towards a moderate reduction of dietary fructose and/or general sugar intake may have a positive effect on BMI in overweight and obese children.  相似文献   
7.
In a consanguineous Turkish family, a locus for autosomal recessive nonsyndromic hearing impairment (ARNSHI) was mapped to chromosome 2q31.1-2q33.1. Microsatellite marker analysis in the complete family determined the critical linkage interval that overlapped with DFNB27, for which the causative gene has not yet been identified, and DFNB59, a recently described auditory neuropathy caused by missense mutations in the DFNB59 gene. The 352-amino acid (aa) DFNB59 gene product pejvakin is present in hair cells, supporting cells, spiral ganglion cells, and the first three relays of the afferent auditory pathway. A novel homozygous nonsense mutation (c.499C>T; p.R167X) was detected in the DFNB59 gene, segregating with the deafness in the family. The mRNA derived from the mutant allele was found not to be degraded in lymphocytes, indicating that a truncated pejvakin protein of 166 aa may be present in the affected individuals. Screening of 67 index patients from additional consanguineous Turkish families with autosomal recessive hearing impairment revealed a homozygous missense mutation (c.547C>T; p.R183W) that segregates with the hearing impairment in one family. Furthermore, in a panel of 83 Dutch patients, two additional novel mutations (c.509_512delCACT; p.S170CfsX35 and c.731T>G; p.L244R), which were not present in ethnically matched controls, were found heterozygously. Together, our data indicate that also nonsense mutations in DFNB59 cause nonsyndromic hearing loss, but that mutations in DFNB59 are not a major cause of nonsyndromic hearing impairment in the Turkish and Dutch population.  相似文献   
8.

Background

Providing sufficient information during a preanesthetic interview may help improve patient understanding and decrease anxiety related to spinal anesthesia. We investigated the effect of video‐based education on anxiety and satisfaction in patients about to undergo spinal anesthesia.

Methods

A total of 198 patients scheduled for minor elective surgery under spinal anesthesia were prospectively enrolled. The State‐Trait Anxiety Inventory (State‐Trait Anxiety Inventory/State and State‐Trait Anxiety Inventory/Trait) questionnaires and visual analog scale were used to measure anxiety levels before the standard anesthesia evaluation was initiated. Then, 100 patients in Group 1 received written, verbal, and video‐based education, whereas 98 patients in Group 2 received only written and verbal instructions regarding spinal anesthesia. Then all participants completed the State‐Trait Anxiety Inventory/State and visual analog scale to evaluate anxiety. Finally, a 5‐point Likert scale was used to measure satisfaction during postoperative period.

Results

No differences were found in the State‐Trait Anxiety Inventory/State, State‐Trait Anxiety Inventory/Trait, or visual analog scale scores between the two groups before the information period. The State‐Trait Anxiety Inventory/State scores evaluating anxiety during the post‐information period were differed in both groups and they found as 36.5 ± 10.0 in Group 1 and 39.6 ± 8.6 in Group 2 (p = 0.033). The 5‐point Likert scale scores to measure satisfaction were stated as 4.5 ± 0.6 in Group 1 and 3.5 ± 1.2 in Group 2 (p < 0.001).

Conclusions

Providing video‐based information during the preanesthetic interview alleviated anxiety and increased satisfaction in patients undergoing spinal anesthesia.  相似文献   
9.
10.
Background: There is limited information regarding myocardial alterations in patients with obstructive sleep apnea syndrome (OSAS) in the absence of pulmonary and cardiac comorbidity. In this study, we aimed to evaluate potential myocardial alterations of these patients and investigate the possible effects of OSAS-related pathological variations on left and right ventricular functions. Methods: We studied 107 consecutive patients who were referred to our sleep laboratory for clinically suspected OSAS and 30 controls without any history or symptoms of sleep-related disorders. Severity of OSAS was quantified by polysomnography. Patients with apnea–hypopnea index (AHI) < 5 were included in the OSAS (−) group (Group 1, n = 22). Subjects with AHI ≥ 5 were considered as OSAS and classified according to their AHI as mild-to-moderate (AHI ≥ 5 and AHI < 30) (Group 2, n = 45) and severe (AHI ≥ 30) OSAS groups (Group 3, n = 40). Conventional M-mode, 2D, and Doppler mitral inflow parameters, tissue Doppler velocities, myocardial peak systolic strain, and strain rate values of various segments were measured and compared between groups. Results: Patients with OSAS displayed impairment of left ventricular diastolic function compared with controls. There were no significant differences between groups regarding parameters reflecting left ventricular systolic function. Myocardial strain analysis demonstrated significant decrement regarding apical right ventricular longitudinal peak systolic strain and strain rate values between groups in relation to the severity of OSAS. Conclusions: Patients with OSAS display a regional pattern of right ventricular dysfunction correlated with the severity of disease.  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