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   1259篇
  免费   63篇
  国内免费   14篇
耳鼻咽喉   37篇
儿科学   56篇
妇产科学   85篇
基础医学   112篇
口腔科学   16篇
临床医学   98篇
内科学   388篇
皮肤病学   23篇
神经病学   78篇
特种医学   39篇
外科学   228篇
综合类   18篇
预防医学   23篇
眼科学   54篇
药学   51篇
肿瘤学   30篇
  2023年   3篇
  2022年   15篇
  2021年   25篇
  2020年   11篇
  2019年   27篇
  2018年   33篇
  2017年   32篇
  2016年   47篇
  2015年   57篇
  2014年   73篇
  2013年   100篇
  2012年   84篇
  2011年   101篇
  2010年   51篇
  2009年   68篇
  2008年   101篇
  2007年   111篇
  2006年   76篇
  2005年   80篇
  2004年   54篇
  2003年   42篇
  2002年   45篇
  2001年   16篇
  2000年   8篇
  1999年   5篇
  1998年   4篇
  1997年   12篇
  1996年   4篇
  1995年   3篇
  1994年   5篇
  1993年   5篇
  1992年   12篇
  1991年   11篇
  1990年   3篇
  1989年   1篇
  1988年   2篇
  1986年   2篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
排序方式: 共有1336条查询结果,搜索用时 15 毫秒
31.
AIM:The eradication rate of Helicobacter pylori (H pylon) shows variation among countries and regimens of treatment.We aimed to study the eradication rates of different regimens in our region and some factors affecting the rate of eradication.METHODS:One hundred and sixty-four Hpylori positivepatients (68 males, 96 females; mean age:48±12 years)with duodenal or gastric ulcer without a smoking history were included in the study. The patients were divided into three groups according to the treatment regimens. Omeprazole 20mg, clarithromycin 500mg, amoxicillin 1g were given twice daily for 1 week (Group I) and 2 weeks (Group Ⅱ).Patients in Group Ⅲ received bismuth subsitrate 300mg,tetracyline 500 mg and metronidazole 500mg four times daily in addition to Omeprazole 20mg twice daily.Two biopsies each before and after treatment were obtained from antrum and corpus, and histopathologically evaluated.Eradication was assumed to be successful if no Hpylorus was detected from four biopsy specimens taken after treatment. The effects of factors like age, sex, Hpyloridensity on antrum and corpus before treatment, the total Hpylori density, and the inflammation scores on the rate of Hpylori eradication were evaluated.RESULTS:The overall eradication rate was 42%. The rates in groups Ⅱ and Ⅲ were statistically higher than that in group I (P<0.05). The rates of eradication were 24.5%,40.7% and 61.5% in groups Ⅰ, Ⅱ and Ⅲ, respectively. The eradication rate was negatively related to either corpus Hpylori density or total Hpyloridensity (P<0.05).The median age was older in the group in which the eradication failed in comparison to that with successful eradication (55yr vs 39yr, P<0.001). No correlation between sex and Hpylori eradication was found.CONCLUSION: Our rates of eradication were significantly lower when compared to those reported in literature.We believe that advanced age and high Hpyloridensity are negative predictive factors for the rate of Hpylorieradication.  相似文献   
32.
33.
34.
AIM: To determine whether Helicobacter pylori (H pylori) infection caused hyperhomocysteinemia by altering serum vitamin B_(12), serum folate and erythrocyte folate levels and whether eradication of this organism decreased serum homocysteine level. METHODS: The study involved 73 dyspeptic H pylork positive patients, none of them had gastric mucosal atrophy based on rapid urease test and histology. Out of 73 patients, 41 (56.2%) showed a successful eradication of H pylori 4 wk after the end of treatment. In these 41 patients, fasting serum vitamin B_(12) folate and homocysteine levels, and erythrocyte folate levels before and 4 wk after H pylori eradication therapy were compared. RESULTS: The group with a successful eradication of H pylori had significantly higher serum vitamin B_(12) and erythrocyte folate levels in the post-treatment period compared to those in pre-treatment period (210±97 pg/mL vs 237±94 pg/mL,P<0.001 and 442±212 ng/mL vs 539±304 ng/mL, P=0.024, respectively), but showed no significant change in serum folate levels (5.6±2.6 ng/mL vs 6.0+2.4 ng/mL, P=0.341). Also, the serum homocysteine levels in this group were significantly lower after therapy (13.1±5.2 μmol/L vs 11.9±6.2 μmol/L, P=0.002). Regression analysis showed that serum homocysteine level was positively correlated with age (P=0.01) and negatively with serum folate level before therapy (P=0.003). CONCLUSION: Eradication of H pylori decreases serum homocysteine even in patients who do not exhibit gastric mucosal atrophy. It appears that the level of homocysteine in serum is related to a complex interaction among serum vitamin B_(12), serum folate and erythrocyte folate levels.  相似文献   
35.

Objective

We aimed to examine left–right asymmetry in involved and total neck lymph nodes distribution in patients with bilateral laryngeal cancer in the present study.

Methods

Forty-six patients with bilateral laryngeal cancer was included the study. The oncologic database of our otorhinolaryngology department was used. The right and left lymph node with and without involvement by cancer cells counts were retrieved from pathological reports.

Results

The numbers of both involved and total neck lymph nodes were significantly higher on right side than on left side for all neck levels in laryngeal malignancies.

Conclusions

The results of the present study suggest the existence of a left–right asymmetry in neck lymph node distribution and in the neck lymph node distribution involved by laryngeal cancer cells. The stronger cell-mediated immune activity in the left side of humans may be associated with the blocking of the metastatic invasion of cancer cells from laryngeal malignancies in the left body side.  相似文献   
36.
Introduction and objective: In this study, we aimed to investigate the relationship between vitamin D, parathyroid hormone (PTH) and cardiovascular risk (CVR) in hypertensive patients aged 65 years and over.

Patients and methods: This study was performed with 84 hypertensive patients and 68 normotensive control group in Afyon Kocatepe University Faculty of Medicine Hospital. The determined cardiovascular risk degrees and the stages of blood pressure were compared with the levels of 25-(OH) vitamin D and PTH.

Results: Mean systolic and diastolic blood pressure (BP) levels of the patients with vitamin D deficiency (VDD) were significantly higher than those without VDD (p?p?=?0.012, p?=?0.036, respectively). CVR was reversely correlated with vitamin D but the correlation with hyperparathyroidism did not reach statistically significant level (r?=?–0.752, p?r?=?0.210, p?=?0.055), respectively.

Conclusion: These results indicate that the presence of hypertension is associated with VDD, as well as the stage of hypertension contributes to insufficiency, hyperparathyroidism and increased CVR. Clinicians should be aware and perhaps more aggressive for the treatment of HT and VDD in patients over 65 years of age.  相似文献   
37.
The determination of the approximately truest value in height measurement is important in many fields, but it is difficult to perform true measurements, especially in the elderly individuals. We planned to investigate the following items in geriatric Turkish population: to calculate the decrease in height with advancing age by using the standing height measurement and estimated height derived from the knee height; to evaluate the significance of difference between the two measurement methods in the calculation of body mass index (BMI) and waist/height ratio (WHtR); to determine the cut-off value of WHtR according to estimated height in elderly individuals. We studied 551 cases aged between 19 and 97 years. Knee height was measured using a sliding caliper in a sitting position. Linear regression analysis was carried out to derive predictive equations for the estimation of stature with adults (≤50 years of age) according to the gender. This equation was then used to estimate height among elderly subjects. Of the cases, 60.3% were <60 years (mean: 48.75 ± 7.50); 39.7% of the cases were >60 years (mean: 69.51 ± 7.12). Estimated BMI (EBMI) measurements in the females and males >60 years were in average 1.23 kg/m2 and 0.92 kg/m2 higher than their real BMIs, respectively. EBMI measurements in the females <60 years were 0.32 kg/m2 higher than their real BMIs (p < 0.01). There is a statistically significant difference between WHtR in the females of both age groups, and in the males >60 years, as compared to our estimated WHtR (EWHtR) measurements (p < 0.01). The cut-off point of WHtR was 0.61 and 0.58 in the female and male cases of >60 years in our study, respectively. WHtR seemed to be a better anthropometric index that could predict most cardiometabolic risk factors in our study. EWHtR emerged to be a better cardiometabolic risk index especially in the elderly group.  相似文献   
38.
The FES-I is a questionnaire which was developed to assess fear of falling. The aim of this study was to evaluate validity and reliability of a Turkish language version of the FES-I in Turkish older people. The study sample included 70 volunteers with an age range of 65-81. To assess the test-retest reliability of the Turkish FES-I, questionnaire was applied again 10-15 days after the first interview (interclass correlation: ICC). FES-I was compared with The Modified Barthel Index (MBI), the timed up and go test (TUG), and The Berg Balance Scale (BBS) for construct validity. Cronbach's alpha (α) was used to evaluate the internal consistency. The internal structure of the FES-I was examined by factor analysis. ROC plots were used to define cut-point for the FES-I scales. Cronbach's α of the Turkish FES-I was 0.94 and the individual item ICC ranged from 0.97 to 0.99. The Turkish FES-I total scores were correlated with TUG positively, and MBI, and BBS negatively. The cut-off score to differentiate between persons with fear of falling and persons without fear of falling was 24 points. It was found that the Turkish version of the FES-I was a reliable and valid measure of fear of falling in Turkish older people.  相似文献   
39.
40.
Carbohydrate antigen-125 (CA-125) is emerging as a prognostic biomarker of risk in heart failure. In a prospective study, we compared the prognostic values of CA-125 and amino-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with stable heart failure.We enrolled 102 consecutive chronic, stable, systolic-heart-failure patients (68 men and 34 women; median age, 71 yr) from November 2008 through February 2010. We measured baseline NT-proBNP and CA-125 levels and compared their prognostic values. The primary endpoint was all-cause death and other major adverse events, defined as hospitalization for decompensated heart failure or acute coronary syndrome.During a mean follow-up period of 14 ± 2 months, 12 patients died and 35 others sustained major adverse events. We found that CA-125 level significantly correlated with New York Heart Association functional class, pulmonary artery pressure, microalbuminuria, creatine kinase-MB fraction, and hemoglobin, albumin, and NT-proBNP levels. Upon receiver operating characteristic curve analysis, CA-125 and NT-proBNP had similar accuracy in predicting major adverse events and death: for major adverse events, area under the curve (AUC) was 0.699 for CA-125 (P=0.002) and 0.696 for NT-proBNP (P=0.002); for death, AUC was 0.784 for CA-125 (P=0.003) and 0.824 for NT-proBNP (P=0.001). Multivariate Cox regression analysis showed that CA-125 levels greater than 32 U/mL and NT-proBNP levels greater than 5,300 pg/mL had independent prognostic value for major adverse events and death.We conclude that baseline CA-125 and NT-proBNP levels are comparably reliable as heart-failure markers, and that CA-125 can be used for prognosis prediction in heart failure.  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