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   613篇
  免费   38篇
  国内免费   12篇
耳鼻咽喉   6篇
儿科学   26篇
妇产科学   15篇
基础医学   67篇
口腔科学   12篇
临床医学   54篇
内科学   204篇
皮肤病学   15篇
神经病学   59篇
特种医学   11篇
外科学   62篇
综合类   1篇
预防医学   46篇
眼科学   15篇
药学   30篇
中国医学   1篇
肿瘤学   39篇
  2024年   1篇
  2023年   9篇
  2022年   16篇
  2021年   30篇
  2020年   21篇
  2019年   31篇
  2018年   23篇
  2017年   25篇
  2016年   22篇
  2015年   25篇
  2014年   41篇
  2013年   47篇
  2012年   71篇
  2011年   62篇
  2010年   36篇
  2009年   26篇
  2008年   37篇
  2007年   33篇
  2006年   36篇
  2005年   30篇
  2004年   15篇
  2003年   5篇
  2002年   8篇
  2001年   2篇
  2000年   7篇
  1998年   3篇
  1985年   1篇
排序方式: 共有663条查询结果,搜索用时 15 毫秒
71.
Research questionSex hormone-binding globulin (SHBG), androgen receptor (AR), LH beta polypeptide (LHB), progesterone receptor membrane component 1 (PGRMC1) and progesterone receptor membrane component 2 (PGRMC2) regulate follicle development and maturation. Their mRNA expression was assessed in peripheral blood mononuclear cells (PBMC) of normal and poor responders, during ovarian stimulation.DesignFifty-two normal responders and 15 poor responders according to the Bologna criteria were enrolled for IVF and intracytoplasmic sperm injection and stimulated with 200 IU of follitrophin alpha and gonadotrophin-releasing hormone antagonist. HCG was administered for final oocyte maturation. On days 1, 6 and 10 of stimulation, blood samples were obtained, serum hormone levels were measured, RNA was extracted from PBMC and real-time polymerase chain reaction was carried out to identify the mRNA levels. Relative mRNA expression of each gene was calculated by the comparative 2?DDCt method.ResultsDifferences between mRNA levels of each gene on the same time point between the two groups were not significant. PGRMC1 and PGRMC2 mRNA levels were downregulated, adjusted for ovarian response and age. Positive correlations between PGRMC1 and AR (standardized beta = 0.890, P < 0.001) from day 1 to 6 and PGRMC1 and LHB (standardized beta = 0.806, P < 0.001) from day 1 to 10 were found in poor responders. PGRMC1 and PGRMC2 were positively correlated on days 6 and 10 in normal responders.ConclusionsPGRMC1 and PGRMC2 mRNA are significantly decreased during ovarian stimulation, with some potential differences between normal and poor responders.  相似文献   
72.
73.

Background

To investigate optical coherence tomography (OCT) measurements following implantation of the LENTIS Mplus multifocal IOL, compared with a control group.

Methods

OCT scans were performed on 50 eyes with the Topcon 3D OCT-1000 in two groups of patients. The first group consisted of patients following implantation of the LENTIS Mplus, and a second group of age-matched control eyes following implantation of a monofocal aspheric IOL. Macular thickness and macular volume values were compared between groups and assessment for any onscreen visible artifacts.

Results

OCT scans were successfully performed in all 50 eyes with no visible artifacts in either group during scan acquisitions. There were no statistically significant differences (p?>?0.05) in any measured or calculated macular thickness or volume values between the two groups.

Conclusions

OCT measurements with the Topcon 3D OCT-1000 is possible and free from visible artifacts in eyes which have had the LENTIS Mplus multifocal IOL implanted. Macular thickness and volume values were similar to those of an age-matched control group of monofocal aspheric IOLs.  相似文献   
74.
Cancer and treatment-related anaemia is a significant clinical problem. Erythropoiesis stimulating agents (ESA) improve anaemia and ultimately enhance patients' quality of life. However, about one-third of patients do not respond to ESA administration, mostly because of the impaired supply of iron to the erythroid marrow (functional iron deficiency). Concomitant administration of intravenous (IV) iron may improve responsiveness. The use of baseline predictors of response to ESA and of indicators of appropriateness of response and iron availability should allow targeted therapeutic interventions with both ESA and IV iron. Several biochemical and haematological indicators of response and of iron balance have been studied, but firm criteria for their use have not yet been rigorously established. The commonly used early predictive markers of response to ESA, such as baseline endogenous erythropoietin levels and an increase in haemoglobin, reticulocytes, and soluble transferrin receptor levels during ESA treatment, have not proved reliable due to their low sensitivity and specificity. Traditional markers of iron availability, such as serum ferritin and transferrin saturation display interpretation pitfalls. The need for predictors and indicators of responsiveness to ESA and IV iron is still current and clinically relevant.  相似文献   
75.

Background

Increased thermal heterogeneity has been demonstrated in atherosclerotic plaques, with the higher temperature recorded in acute myocardial infarction (MI). Dietary or treatment interventions reduce heat production. The purpose of the present study was to investigate whether increased plaque temperature is maintained for a prolonged period after MI and the role of statin administration.

Methods

We enrolled 55 patients, 29 with recent MI and 26 with chronic stable angina (CSA). Total cholesterol, C-reactive protein (CRP), interleukin-6 (IL-6) and soluble adhesion molecules were measured in the study population. All patients underwent coronary plaque temperature measurements. Temperature difference (ΔT) was designated as the temperature of the culprit atherosclerotic plaque minus the temperature of the proximal healthy vessel wall.

Results

Under treatment with statins were 19 patients with recent MI and 14 with CSA. In patients with recent MI ΔT was 0.19 ± 0.18°C, while in patients with CSA was 0.10 ± 0.08°C (P = .03). Patients treated with statins had lower ΔT compared to untreated patients (0.10 ± 0.11 versus 0.20 ± 0.18°C, P = .01). Treated patients with recent MI had similar ΔT compared to CSA patients treated with statins (0.13 ± 0.13 versus 0.07 ± .06° C, P = .14), while untreated patients with recent MI had substantially increased ΔT compared to untreated patients with CSA (0.28 ± 0.22 versus 0.14 ± 0.10°C, P = .04). ΔT was positively correlated with CRP (R = 0.50, P < .01), IL-6 (R = 0.58, P < .01), and intercellular adhesion molecule-1 (R = 0.40, P = .03) levels.

Conclusion

Increased plaque temperature is observed for an extended period after myocardial infarction, indicating that the inflammatory process is sustained after plaque rupture. Statins have a beneficial effect after MI on plaque temperature.  相似文献   
76.
BACKGROUND/AIMS: To analyze the efficacy of chemoembolization prior to liver transplantation in liver explants. METHODOLOGY: We reviewed pathological findings in the explanted livers of 21 patients with histologically proven hepatocellular carcinoma and liver cirrhosis who underwent transarterial chemoembolization (TACE) prior to liver transplantation. Nine patients had solitary nodules with a median diameter of 4 cm (range 1.5-7 cm), 7 patients had 2 or 3 tumors with a median total diameter of 5.9 cm (range 3-9 cm) and 5 patients had a multifocal tumor prior to TACE. Pathological up-staging of the clinical tumor classification was documented as "tumor-progression." Concurrence of clinical and pathological findings was documented as "steady disease". "Tumor regression" described those cases in which the pathological classification downgraded the clinical findings. RESULTS: There was no treatment-related morbidity in these patients' group. Tumor regression was proved in 11/21 patients (52.4%) whereas steady disease was observed in 7/21 patients (33.4%). In 5 patients (23.8%) no vital tumor was found by pathological examination. Tumor regression was observed only in one of the five patients having a multifocal tumor prior to TACE. Tumor progression was observed in 3/21 patients (14.3%). CONCLUSIONS: Our data show that TACE provides acceptable local tumor control as bridging treatment before liver transplantation. Although the majority of our patients (15/21, 71.4%) had 2 or more tumor lesions at the beginning of treatment, tumor progression was observed in only a minority (14.3%) of patients. However, multifocal tumors could not be successfully under-staged through this treatment and, furthermore, vital tumor was always observed in pathology; the usefulness of TACE in multifocal disease has to be re-estimated.  相似文献   
77.
Pruritus is an alarming symptom in patients with end-stage renal disease (ESRD) accompanied by sleep disturbances and physical and mental disorders. Although its prevalence is very high among hemodialysis patients (90%), its etiology and its successful treatment have been unconfirmed (Melo N, Elias R, Castro M, Romao G, Abensur H. Pruritus in hemodialysis patients: The problem still remains. Hemodial Int. 2009;13:38-42.). Common pruritus etiologies, such as high parathyroid hormone levels, dialysis inadequacy, and iron deficiency are matters of conflict. The case of a hemodialysis patient with consistent itching and a variety of cutaneous eruptions, which after performing skin biopsy were explored and cured, is described. This article addresses the possibility of other causes of pruritus in ESRD and encourages watchful waiting with simple medical interventions, which would relieve patients' symptoms.  相似文献   
78.
Reports on the success of permanent vascular access in elderly HD patients vary considerably. We reviewed the records of 149 patients [62F and 87M] aged 20–89 years old (median 59) who were on hemodialysis for 6–242 (49 median) months, and had undergone 202 vascular access procedures (177 Cimmino-Brescia fistulae and 25 PTFE grafts). Patients were divided into two groups according to the age they started HD. Group A: 48 patients, over 60 years old (range 60–83; median 70) on HD for 43.5, (6–140) months. Group B: 101 patients, under 60 years old, range (15–59) median 46, on HD for 54 (6–242) months. There were no differences between the two groups in terms of gender, primary renal disease, (except polycystic kidney disease), Hct and EPO administration. The initial choice of vascular access, the complications and the technique survival were examined in both groups. Cimmino-Brescia fistulae were used as the first choice of vascular access in all patients except one in group B. PTFE-grafts were the second or third choice in 7/48 (group A) and 15/101 (group B) (p: NS). The only reason for technique failure was vascular thrombosis in both groups (11/48 group A and 31/101 group B p: NS). Other complications were: aneurysms (10/48 and 14/101, p: NS), infections (0/48 and 2/101 p: NS) and edema (0/48 and 6/101, p: NS). Five-year technique survival of the first AV fistula in the two groups was 35% and 45% respectively (log-rank test, p: NS). These findings suggest that: a) A.V. fistula is the first choice of vascular access in aged HD patients; b) There is no difference in vascular access complications across age groups; c) Survival of the first A.V. fistula is independent of age.  相似文献   
79.
Treatment issues in clear cell carcinoma of the ovary: a different entity?   总被引:2,自引:0,他引:2  
BACKGROUND: Ovarian clear cell carcinoma (OCCC) is a distinct histopathologic subtype of epithelial ovarian cancer (EOC) with an incidence of <5% of all ovarian malignancies. Our goal was to review the clinical features and management of patients with OCCC. METHODS AND RESULTS: We performed a PubMed search using the phrase "clear cell ovarian cancer." We reviewed 54 articles referring to OCCC. OCCC patients have a high incidence of stage I disease and frequently present with a large pelvic mass. Recurrences are more frequent with this entity than with other types of EOC. The clinical management of advanced EOC includes maximal cytoreduction and platinum plus paclitaxel-based chemotherapy. The survival rates of patients with advanced OCCC are lower than those of patients with advanced serous EOC (serous subtype). The poor response rate to platinum-based regimens may be related to the intrinsic chemoresistance of these tumors. Despite their aggressive clinical course, OCCCs are still treated similarly to the other EOCs at the present time, because the rarity of these tumors prevents the conduction of randomized studies. CONCLUSION: Novel treatment approaches should be adopted in OCCC. Molecular-targeted therapies and effective new agents without cross-resistance to platinum compounds should be evaluated in a prospective clinical trial in OCCC.  相似文献   
80.
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