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   5051篇
  免费   323篇
  国内免费   51篇
耳鼻咽喉   45篇
儿科学   84篇
妇产科学   79篇
基础医学   596篇
口腔科学   86篇
临床医学   365篇
内科学   1506篇
皮肤病学   92篇
神经病学   425篇
特种医学   150篇
外科学   903篇
综合类   42篇
一般理论   2篇
预防医学   136篇
眼科学   76篇
药学   255篇
中国医学   8篇
肿瘤学   575篇
  2023年   48篇
  2022年   90篇
  2021年   143篇
  2020年   69篇
  2019年   111篇
  2018年   134篇
  2017年   120篇
  2016年   143篇
  2015年   162篇
  2014年   160篇
  2013年   178篇
  2012年   279篇
  2011年   320篇
  2010年   175篇
  2009年   160篇
  2008年   267篇
  2007年   287篇
  2006年   251篇
  2005年   264篇
  2004年   251篇
  2003年   194篇
  2002年   222篇
  2001年   113篇
  2000年   115篇
  1999年   97篇
  1998年   58篇
  1997年   45篇
  1996年   47篇
  1995年   26篇
  1994年   35篇
  1993年   38篇
  1992年   84篇
  1991年   87篇
  1990年   57篇
  1989年   74篇
  1988年   59篇
  1987年   58篇
  1986年   58篇
  1985年   59篇
  1984年   33篇
  1983年   35篇
  1982年   12篇
  1979年   25篇
  1978年   26篇
  1977年   22篇
  1972年   10篇
  1969年   18篇
  1968年   21篇
  1967年   9篇
  1966年   10篇
排序方式: 共有5425条查询结果,搜索用时 15 毫秒
151.
European Archives of Oto-Rhino-Laryngology - Papillary thyroid carcinoma frequently metastasizes to central and lateral neck lymph nodes, but metastasis to retropharyngeal lymph nodes (RPLN) is...  相似文献   
152.
BACKGROUND: When comparing with early-onset Alzheimer's disease (EO-AD) and late-onset Alzheimer's disease (LO-AD), some symptomatological differences in clinical features can be seen between them. Rapid progression, more severe language problems or visuospatial dysfunction occur more often in EO-AD patients. However, there have been very few reports about the differences in behavioral and psychological symptoms between these two groups. AIM: The aim of this study was to demonstrate the differences in behavioral symptoms between EO-AD and LO-AD groups. METHOD: Three hundred and seven consecutive outpatients with AD were put into an EO-AD group (46 patients) or a LO-AD group (261 patients). Comprehensive assessment batteries, including the Neuropsychiatric Inventory (NPI), were administered at the first medical assessment. RESULTS: Significant differences were found between the EO-AD and LO-AD groups in terms of NPI total score (EO-AD: 10.3 +/- 10.9, LO-AD: 17.8 +/- 17.0, p = 0.004) and number of patients who experienced each NPI subscale score (delusion; EO-AD: 13.0%, LO-AD: 50.6%, p < 0.001). There were no differences in cognitive functions or dementia severity between two groups. CONCLUSION: In EO-AD, behavioral and psychological symptoms are relatively fewer than LO-AD at the first medical assessment. Copyright (c) 2007 John Wiley & Sons, Ltd.  相似文献   
153.
154.
Adenovirus-mediated ex vivo gene transfer of basic fibroblast growth factor (bFGF), a new strategy for the treatment of chronic vascular occlusive disease, was examined in a rabbit model of hind limb ischemia. The left femoral artery was completely excised to induce an ischemic state in the hind limb of male rabbits. Simultaneously, a skin section was resected from the wound, and host fibroblasts were cultured. The cultured fibroblasts were infected with adenovirus vector containing modified human bFGF cDNA with the secretory signal sequence (AxCAMAssbFGF) or LacZ cDNA (AxCALacZ). At 21 days after femoral artery excision, the gene-transduced fibroblasts were administered through the left internal iliac artery. The fibroblasts significantly accumulated in the ischemic hind limb, and the AxCAMAssbFGF-treated cells secreted bFGF for less than 14 days without elevation of systemic bFGF level. At 28 days after cell administration, calf blood pressure ratio, angiographic score, capillary density of muscle tissue and blood flow of the left internal iliac artery were determined, and animals with AxCAMAssbFGF-treated cells showed significantly greater development of collateral vessels, as compared with those with AxCALacZ-treated cells. These findings suggest that adenovirus-mediated ex vivo gene transfer of bFGF was effective for improvement of chronic limb ischemia.  相似文献   
155.

Background Context

There is a lack of information about postoperative outcomes and related risk factors associated with spinal surgery in patients with Parkinson's disease (PD).

Purpose

This study aimed to investigate the postoperative morbidity and mortality associated with spinal surgery for patients with PD, and the risk factors for poor outcomes.

Study Design

This is a retrospective matched-pair cohort study.

Patient Sample

Data of patients who underwent elective spinal surgery between July 2010 and March 2013 were extracted from the Diagnosis Procedure Combination database, a nationwide inpatient database in Japan.

Outcome Measures

In-hospital mortality and occurrence of postoperative complications.

Methods

For each patient with PD, we randomly selected up to four age- and sex-matched controls in the same hospital in the same year. The differences in in-hospital mortality and occurrence of postoperative complications were compared between patients with PD and controls. A multivariable logistic regression model fitted with a generalized estimation equation was used to identify significant predictors of major complications (surgical site infection, sepsis, pulmonary embolism, respiratory complications, cardiac events, stroke, and renal failure). Multiple imputation was used for missing data.

Results

Among 154,278 patients undergoing spinal surgery, 1,423 patients with PD and 5,498 matched controls were identified. Crude in-hospital mortality was higher in patients with PD than in controls (0.8% vs. 0.3%, respectively). The crude proportion of major complications was also higher in patients with PD (9.8% vs. 5.1% in controls). Postoperative delirium was more common in patients with PD (30.3%) than in controls (4.3%). Parkinson's disease was a significant predictor of major postoperative complications, even after adjusting for other risk factors (odds ratio, 1.74; 95% confidence intervals, 1.37–2.22; p<.001).

Conclusions

Patients with PD had a significantly increased risk of postoperative complications following spinal surgery. Postoperative delirium was the most frequently observed complication.  相似文献   
156.

Purpose

The Oswestry Disability Index (ODI) is one of the most common scoring systems used for patients with low back pain (LBP). Although the normative score of the ODI was reported to be 10.19 in a review article, no study has calculated the normative score after adjusting the value based on the age distribution. In addition, none of the previous studies has estimated the cut-off value which separates LBP with disability from LBP without disability. The purpose of this study was to estimate the normative score by adjusting the data for age distribution in Japan, and to determine the cut-off value which separates LBP with disability from LBP without disability.

Methods

We conducted an internet survey on LBP using the Japanese version of the ODQ. A total of 1,200 respondents, composed of 100 males and 100 females in each age group (from the 20s to 70s), participated in this study. We also asked them to provide information about their backgrounds. We estimated the normative score after correcting for the age distribution of Japan. We also estimated the ODI of those with or without disability, the factors associated with the ODI, and the cut-off value which separates LBP with disability from LBP without disability.

Results

The participants’ backgrounds were similar to the national survey. The normative score of the ODI was estimated at 8.73. The ODI of the LBP with disability group was 22.07. Those with sciatica and obese subjects showed higher ODI than those without. The optimal cut-off value was estimated to be 12.

Conclusions

We defined the normative score and the cut-off value of the ODI.  相似文献   
157.
A 29-year-old man with a type 4 tumor, in the lower third of the stomach, and carcinomatous ascites was diagnosed by aspiration cytology of the ascitic fluid. Curative resection was considered impossible, and S1 (120 mg/d) and cisplatin (90 mg/d) were given for 21 days in 1 course. The cancer lesion showed marked remission (partial response), and the ascites completely disappeared after the fourth course. Twenty-five days after completion of the S1 treatment, laparoscopy-assisted total gastrectomy was performed. Histopathological examination showed no remnant cancer cells in the resected specimen and no lymph node metastases. The tumor was replaced with fibrosis having a granulomatous change. The patient's postoperative course was uneventful. The patient was continued with S1 monotherapy after surgery, and no signs of recurrence or metastases have been seen on any examination 12 months after the surgery.  相似文献   
158.
Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer, FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous cell cancer and PET findings on FDG uptake. Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the primary lesion, and cell density of the tumor. Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation, but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage of tumor parenchyma. Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in cancer tissue tends to become a false negative.  相似文献   
159.
160.
ROS1‐rearranged lung adenocarcinoma has been recently identified. We report a case of ROS1‐rearranged lung adenocarcinoma with special emphasis on cytological findings. Here, we report a case of young woman with ROS1‐rearranged lung adenocarcinoma diagnosed by cytology and discuss the clinical, cytological, and molecular findings. Cytologically, the tumor consisted of small tight clusters of cells with high nuclear/cytoplasmic ratio. Nuclei were enlarged and small nucleoli were occasionally observed. Signet‐ring cells were focally identified. Neoplastic cells were positive for ROS1 immunocytochemistry. Subsequently, the translocation of ROS1 gene was confirmed in a histological specimen. In conclusion, the specific histology of adenocarcinoma on cytological materials should promote testing for ROS1 immunohistochemistry. Immunocytochemical detection of ROS1 protein helps identify patients suitable for molecular targeted therapy.  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