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   3916篇
  免费   205篇
  国内免费   21篇
耳鼻咽喉   102篇
儿科学   195篇
妇产科学   224篇
基础医学   315篇
口腔科学   169篇
临床医学   350篇
内科学   824篇
皮肤病学   76篇
神经病学   194篇
特种医学   277篇
外科学   882篇
综合类   46篇
一般理论   1篇
预防医学   90篇
眼科学   129篇
药学   113篇
中国医学   2篇
肿瘤学   153篇
  2024年   6篇
  2023年   24篇
  2022年   26篇
  2021年   86篇
  2020年   54篇
  2019年   87篇
  2018年   121篇
  2017年   100篇
  2016年   137篇
  2015年   158篇
  2014年   178篇
  2013年   232篇
  2012年   346篇
  2011年   344篇
  2010年   186篇
  2009年   173篇
  2008年   299篇
  2007年   302篇
  2006年   267篇
  2005年   219篇
  2004年   195篇
  2003年   130篇
  2002年   113篇
  2001年   61篇
  2000年   52篇
  1999年   44篇
  1998年   18篇
  1997年   18篇
  1996年   9篇
  1995年   9篇
  1993年   6篇
  1992年   17篇
  1991年   13篇
  1990年   9篇
  1989年   6篇
  1988年   5篇
  1987年   11篇
  1986年   6篇
  1985年   5篇
  1983年   4篇
  1982年   5篇
  1980年   5篇
  1979年   4篇
  1977年   5篇
  1976年   5篇
  1975年   4篇
  1974年   4篇
  1973年   4篇
  1972年   5篇
  1971年   4篇
排序方式: 共有4142条查询结果,搜索用时 15 毫秒
91.
92.
Testicular tumours have many different manifestations, including hydrocele formation. Herein, we present an extremely rare case of testicular mesothelioma presenting with left hydrocele, but without risk factors. Left radical inguinal orchidectomy was performed, and pathological examination revealed a malignant mesothelioma of the tunica vaginalis of the testis. No infiltration of the spermatic cord was evident, and upon advanced radiological evaluation, no sign of metastasis was detected. Follow-up was still ongoing in our urology outpatient clinic at the time of this report. Although hydrocele is a simple and common condition that is easy to diagnose, a detailed investigation should be performed. Thus, when encountering a patient with hydrocele, the clinician should evaluate the possibility of the presence of an underlying testicular/paratesticular tumour, including a rare one such as mesothelioma of the tunica vaginalis.  相似文献   
93.

Introduction

Serum leptin levels have been examined in various cancers, with conflicting results. However, there is limited information regarding serum leptin levels and insulin resistance in gastric cancer patients. Therefore, we aimed to investigate serum leptin levels, performance status, insulin levels and insulin resistance in patients with gastric cancer. In addition, we examined the relationship between these measurements and leptin levels.

Material and methods

Thirty-nine patients with gastric cancer and 30 control subjects were enrolled in the study. Serum leptin, total protein, albumin, growth hormone, insulin and glucose levels were measured. The homeostasis model assessment (HOMA) was used to assess insulin resistance.

Results

Serum levels of insulin, glucose and growth hormone and insulin resistance were significantly lower in gastric cancer patients than controls (p < 0.05 for all). In the Pearson correlation analysis, insulin resistance was found to be significantly correlated with serum leptin levels in gastric cancer patients (r = 0.320, p = 0.047). We observed a significant negative correlation between performance status and insulin resistance in patients with cachexia (r = –0.512, p = 0.030), while no association was found in non-cachectic patients.

Conclusions

We concluded that serum leptin levels are significantly lower in gastric cancer patients. In addition, gastric cancer patients have decreases in insulin levels, insulin resistance and growth hormone levels. This study found a positive association between serum leptin levels and insulin resistance. Moreover, there is a negative association between serum leptin levels and growth hormone levels. Thus, low insulin and growth hormone levels may suppress the production of leptin in gastric cancer patients.  相似文献   
94.
95.
New antibiotic options are urgently needed for the treatment of carbapenem-resistant Enterobacteriaceae infections. We report a 64-year-old female with prolonged hospitalization following an intestinal transplant who developed refractory bacteremia due to a serine carbapenemase-producing pandrug-resistant isolate of Klebsiella pneumoniae. After failing multiple antimicrobial regimens, the patient was successfully treated.  相似文献   
96.

Background/Aims:

There are a limited number of studies including the impact of antiplatelet drugs use on hospital outcomes for nonvariceal upper gastrointestinal bleeding. The aim of this study was to determine the effect of anti-aggregant, anti-coagulant and non-steroidal anti-inflammatory drugs upon hospital outcomes in patients with peptic ulcer bleeding.

Materials and Methods:

The patients under treatment with antiaggregant, anticoagulant or non-steroidal anti-inflammatory drugs were categorized as exposed group (n = 118) and the patients who were not taking any of these drugs were categorized as non-exposed group (n = 81). We analyzed the data of drug intake, comorbid disease, blood transfusion, duration of hospital stay, Blatchford/total Rockall score and diagnosis of patients.

Results:

In total, 199 patients were included. Of these 59.3% (exposed group) were taking drugs. The patients in exposed group were significantly older than those in non-exposed group (62.9 ± 17.3 years; 55.5 ± 19.3 years, P = 0.005, respectively). Mean number of red blood cell units transfused (2.21 ± 1.51; 2.05 ± 1.87, P = 0.5), duration of hospital stay (3.46 ± 2.80 days; 3.20 ± 2.30 days, P = 0.532) and gastric ulcer rate (33% vs 23.4%, P = 0.172) were higher in exposed group than in non-exposed group but the differences were not statistically significant. Total Rockall and Blatchford scores of the patients were significantly higher in exposed group than in non-exposed group (3.46 ± 1.72 vs 2.94 ± 1.87, P = 0.045; 10.29 ± 3.15 vs 9.31 ± 3.40, P = 0.038).

Conclusıon:

Our study has shown that anticoagulants, antiaggregants and nonsteroidal anti-inflammatory drugs do not effect duration of hospital stay, red blood cell transfusion requirement and rebleeding for peptic ulcer bleeding.  相似文献   
97.
Cardiovascular complications are the most common causes of morbidity and mortality in acromegaly. However, there is little data regarding cardiac autonomic functions in these patients. Herein, we aimed to investigate several parameters of cardiac autonomic functions in patients with acromegaly compared to healthy subjects. We enrolled 20 newly diagnosed acromegalic patients (55 % female, age:45.7 ± 12.6 years) and 32 age- and gender-matched healthy subjects. All participants underwent 24 h Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting 1st, 2nd and 3rd minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV) and QT dynamicity analysis. Baseline characteristics were similar except diabetes mellitus and hypertension among groups. Mean HRR1 (29.2 ± 12.3 vs 42.6 ± 6.5, p = 0.001), HRR2 (43.5 ± 15.6 vs 61.1 ± 10.8, p = 0.001) and HRR3 (46.4 ± 16.2 vs 65.8 ± 9.8, p = 0.001) values were significantly higher in control group. HRV parameters as, SDNN [standard deviation of all NN intervals] (p = 0.001), SDANN [SD of the 5 min mean RR intervals] (p = 0.001), RMSSD [root square of successive differences in RR interval] (p = 0.001), PNN50 [proportion of differences in successive NN intervals >50 ms] (p = 0.001) and high-frequency [HF] (p = 0.001) were significantly decreased in patients with acromegaly; but low frequency [LF] (p = 0.046) and LF/HF (p = 0.001) were significantly higher in acromegaly patients. QTec (p = 0.009), QTac/RR slope (p = 0.017) and QTec/RR slope (p = 0.01) were significantly higher in patients with acromegaly. Additionally, there were significant negative correlation of disease duration with HRR2, HRR3, SDNN, PNN50, RMSSD, variability index. Our study results suggest that cardiac autonomic functions are impaired in patients with acromegaly. Further large scale studies are needed to exhibit the prognostic significance of impaired autonomic functions in patients with acromegaly.  相似文献   
98.
Bladder urothelial carcinoma is rare in young adults and occurs more commonly in older individuals. The aim of this study was to compare the clinical behavior, pathologic characteristics, and prognosis of urothelial carcinoma of urinary bladder in young versus older adults. A retrospective review of our records between 2007 and 2013 identified 56 patients (42 males and 14 females) with transitional cell carcinoma of the bladder who were less than 40 years old. Clinical and pathological parameters of patients who were less than 40 years of age were compared with those of a series of patients older than 40 years of age (the control group) during the same period. A survival analysis was performed using the Kaplan–Meier method and log-rank test, and Cox regression was performed to identify clinical parameters that affected the clinical outcomes. The mean age was 29.21 years (range, 5–40 years) for patients less than 40 years old and 61.66 years (range, 41–75) for those older than 40 years. The mean follow-up was 40.26 months (range, 12–65 months) for young patients and 42.57 months (range, 12–72 months) for the older patients. Young bladder cancer patients had smaller-sized tumors (less than 3 cm), less high-grade cancers, higher papillary urothelial neoplasms of low malignant potential, and low-grade tumors than patients older than 40 years. Multivariate logistic regression analysis predicted tumor recurrence in young patients with high-grade tumors [odds ratio (OR), 1.959; 95% confidence interval (CI), 1.235–2.965; p = 0.046] and tumors larger than 3 cm (OR, 1.772; 95% CI, 1.416–1.942; p = 0.032). The 5-year overall survival rate was 100% for young patients and 88.1% for older patients. No difference was observed in the recurrence-free (p = 0.321) and progression-free (p = 0.422) survival rates between the two groups. We concluded that although the clinical stage distribution, natural history, and outcomes of bladder urothelial cancer in young adults are similar to those in their older counterparts, clinicians must be aware that patients under 40 years of age presented with higher-grade and larger (>3 cm) tumors and are more likely to experience tumor recurrence.  相似文献   
99.
Rocuronium is a nondepolarizing neuromuscular blocking agent used in anesthesia induction and is associated with considerable discomfort and burning pain during injection, which is reported to occur in 50–80% of patients. This study was carried out to investigate the effectiveness of intravenous paracetamol pretreatment compared with lidocaine and normal saline to prevent rocuronium injection pain. The study included 150 ASA I–II patients undergoing elective orthopedic, gastrointestinal, and gynecological procedures under general anesthesia. They were allocated into three groups according to pretreatment drugs: lidocaine (40 mg) (n = 50), paracetamol (n = 50), and normal saline group (n = 50). Before anesthesia induction with propofol, all patients were pretreated with rocuronium. The pain caused by the injection was evaluated. Local signs were assessed on the arm at the end of the injection, as well as 24 hours after recovery from anesthesia. There were no patients with blurred speech or vision and there was no respiratory depression in any group after pretreatment with the study drug. The level of pain on injection was statistically lower in those who had received paracetamol compared to normal saline (p = 0.009). There were more patients in the saline group with severe pain (p < 0.001). Paracetamol relieved the rocuronium injection pain better than normal saline but lidocaine was the best of the three drugs (p < 0.001).  相似文献   
100.

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   
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