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   968篇
  免费   62篇
  国内免费   4篇
耳鼻咽喉   4篇
儿科学   26篇
妇产科学   23篇
基础医学   76篇
口腔科学   55篇
临床医学   59篇
内科学   182篇
皮肤病学   13篇
神经病学   86篇
特种医学   29篇
外科学   231篇
综合类   31篇
预防医学   95篇
眼科学   11篇
药学   70篇
中国医学   2篇
肿瘤学   41篇
  2023年   9篇
  2022年   31篇
  2021年   35篇
  2020年   25篇
  2019年   30篇
  2018年   39篇
  2017年   31篇
  2016年   24篇
  2015年   30篇
  2014年   56篇
  2013年   48篇
  2012年   69篇
  2011年   64篇
  2010年   44篇
  2009年   28篇
  2008年   41篇
  2007年   40篇
  2006年   39篇
  2005年   37篇
  2004年   35篇
  2003年   27篇
  2002年   27篇
  2001年   16篇
  2000年   14篇
  1999年   19篇
  1998年   7篇
  1997年   4篇
  1996年   6篇
  1995年   7篇
  1994年   5篇
  1993年   3篇
  1992年   8篇
  1991年   14篇
  1990年   5篇
  1989年   15篇
  1988年   6篇
  1987年   19篇
  1986年   8篇
  1985年   14篇
  1984年   8篇
  1982年   4篇
  1981年   6篇
  1980年   3篇
  1978年   4篇
  1971年   2篇
  1969年   2篇
  1968年   4篇
  1967年   2篇
  1966年   4篇
  1934年   2篇
排序方式: 共有1034条查询结果,搜索用时 15 毫秒
81.
Overactive bladder (OAB) is a bothersome condition that affects millions of people worldwide. It consists of urgency, incontinence, frequency and nocturia. Treatment, in the form of lifestyle interventions, bladder training and pelvic floor muscle exercises, aim to alleviate symptoms. These treatment modalities have drawbacks, including being time consuming and require stamina on the part of the patient and treating physician. Drugs may be used if conservative measures fail or in combination with them. Antimuscarinics are the mainstay of OAB medication but may cause dry mouth, blurred vision or constipation. It is, therefore, crucial that new treatment modalities are sought to help with this potentially debilitating condition. Antidiuresis, using desmopressin, forms a potential candidate for a novel treatment. As the bladder fills with urine, symptoms of OAB are experienced by patients. It would be reasonable to hypothesise that if the rate of bladder filling is reduced then so would the symptoms of OAB. Desmopressin reduces the production of urine by the kidneys, therefore reducing the amount of urine in the bladder and, therefore, the symptoms of OAB. Desmopressin has been used previously in small single centre trials in neurogenic OAB patients with some success but recently two multi-centre, multinational randomised placebo controlled trials using this concept have been completed in idiopathic OAB sufferers and reported in the literature. The results were quite promising although there were minor side effects. These trials suggest that this potential novel treatment modality for OAB sufferers might avoid the necessity for invasive treatments, such as botulinum toxin, neuromodulation or surgery, in some instances. These trials also open the way to combination therapy with current treatment modalities of OAB.  相似文献   
82.
Objectives:The purpose of this study was to evaluate antioxidant effect of paraoxonase 1 activity and malondialdehyde (MDA) levels as a marker of oxidative stress in patients suffering from cataract due to diabetes and aging.Design and methods:One hundred cataract patients (senile and diabetic) and age- and sex-matched controls were studied. Paraoxonase 1 and arylesterase activities in plasma samples were measured using paraoxon and phenylacetate as substrates, respectively. The magnitude of lipid peroxidation was established by measuring plasma MDA and oxidized low-density lipoprotein (ox LDL) levels. One-way ANOVA was employed for analysis of results.Results:We observed significantly lower plasma paraoxonase and arylesterase activities in senile and diabetic cataractous patients as compared to respective controls (p < 0.001). Plasma MDA and ox LDL levels were found to be higher in patients suffering from cataract (p < 0.001).Conclusions:The results of present study suggest that the observed decrease in PON1 activity may be due to increase in oxidative stress. It can be concluded that lower paraoxonase activity could contribute to the higher risk of cataract formation.  相似文献   
83.
84.
We compared the performance of the LMA Supreme (SLMA) with the I-Gel during anaesthesia in spontaneously breathing adult patients. Ninety patients with American Society of Anesthesiologists physical status I or II were studied in a prospective randomised controlled study. Our primary outcome measure was oropharyngeal leak pressure. We also compared the overall insertion success rate, ease of insertion, adequacy of ventilation and incidence of complications. The mean (SD), oropharyngeal leak pressure for the SLMA was 25.6 (5.1) cmH2O, which was greater than for the I-Gel 20.7 (5.9) cmH2O (P = 0.0001). The first attempt and overall insertion success rates were similar between the two groups (SLMA 97.8 and 97.8%; I-Gel 93.3 and 100%, P = 0.132). The SLMA was rated easier to insert than the I-Gel (P = 0.011), but the time taken for insertion (P = 0.433) was similar. The incidence of complications was low in both groups. The grade of fibreoptic view was better with the I-Gel than the SLMA (P = 0.001). We conclude that in adults with normal airways, the SLMA is easier to insert and provides a higher oropharyngeal leak pressure, but fibreoptic views are better with the i-gel.  相似文献   
85.
Metastasis is a multistep process that culminates in the spread of cells from a primary tumor to a distant site or organs. For tumor cells to be able to metastasize, they have to locally invade through basement membrane into the lymphatic and the blood vasculatures. Eventually they extravasate from the blood and colonize in the secondary organ. This process involves multiple interactions between the tumor cells and their microenvironments. The microenvironment surrounding tumors has a significant impact on tumor development and progression. A key factor in the microenvironment is an acidic pH. The extracellular pH of solid tumors is more acidic in comparison to normal tissue as a consequence of high glycolysis and poor perfusion. It plays an important role in almost all steps of metastasis. The past decades have seen development of technologies to non-invasively measure intra- and/or extracellular pH. Most successful measurements are MR-based, and sensitivity and accuracy have dramatically improved. Quantitatively imaging the distribution of acidity helps us understand the role of the tumor microenvironment in cancer progression. The present review discusses different MR methods in measuring tumor pH along with emphasizing the importance of extracelluar tumor low pH on different steps of metastasis; more specifically focusing on epithelial-to-mesenchymal transition (EMT), and anti cancer immunity.  相似文献   
86.

OBJECTIVE

To report on the high rectal fistula rate associated with salvage high‐intensity focused ultrasound (HIFU) after the failure of combined brachytherapy and external beam radiotherapy (EBRT) for prostate cancer; salvage ablative therapy for prostate cancer is indicated when there is local recurrence after RT, brachytherapy or their combination.

PATIENTS AND METHODS

We retrospectively reviewed all men with prostate cancer treated with HIFU between 1 March 2005 and 31 May 2007, and identified five men treated after the failure of both brachytherapy and EBRT for localized prostate cancer.

RESULTS

Three of the five men had iodine‐seed implantation brachytherapy combined with EBRT as primary treatment, one had high‐dose rate brachytherapy combined with EBRT and one had salvage iodine‐seed brachytherapy for failed EBRT. Three of the five patients developed a recto‐urethral fistula after HIFU.

CONCLUSIONS

The high rate of recto‐urethral fistula formation in this group might reflect an impaired blood supply or HIFU‐associated near‐field heating of the rectal wall. Tissue viability and healing might affect this group regardless of the salvage method. Careful patient selection and avoidance of rectal diagnostic biopsies might minimize the risk. Emerging ablative therapies regarded as less invasive than traditional therapies must be used with caution.  相似文献   
87.
88.
Myeloma involvement of the nervous system is rare. Extensive literature review revealed only a few cases reported from different parts of the world. The presence of CNS symptoms and detection of plasma cells in the CSF is the usual basis of diagnosis. In addition, immunoelectrophoresis and immunofixation for detection of monoclonal protein confirm the diagnosis in some cases, while some authors used flow cytometry and cytogenetic studies on CSF. Reports of multiple myeloma also include unfavorable cytogenetic abnormalities of chromosome 13. We report a case with relapsed CNS multiple myeloma with the detection of elevated b-2 microglobulin (b2M) as a tumor marker in the CSF.  相似文献   
89.
90.
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