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   456篇
  免费   17篇
  国内免费   4篇
耳鼻咽喉   1篇
儿科学   5篇
妇产科学   1篇
基础医学   42篇
口腔科学   22篇
临床医学   16篇
内科学   107篇
皮肤病学   1篇
神经病学   10篇
特种医学   26篇
外科学   57篇
综合类   2篇
预防医学   17篇
药学   26篇
中国医学   1篇
肿瘤学   143篇
  2022年   4篇
  2021年   5篇
  2020年   4篇
  2019年   7篇
  2018年   5篇
  2017年   7篇
  2016年   14篇
  2015年   7篇
  2014年   9篇
  2013年   8篇
  2012年   30篇
  2011年   26篇
  2010年   12篇
  2009年   12篇
  2008年   23篇
  2007年   21篇
  2006年   11篇
  2005年   7篇
  2004年   16篇
  2003年   20篇
  2002年   22篇
  2001年   22篇
  2000年   23篇
  1999年   19篇
  1998年   7篇
  1997年   8篇
  1996年   9篇
  1994年   6篇
  1993年   6篇
  1992年   10篇
  1991年   9篇
  1990年   9篇
  1989年   12篇
  1988年   7篇
  1987年   6篇
  1986年   9篇
  1985年   5篇
  1984年   2篇
  1978年   7篇
  1977年   3篇
  1974年   2篇
  1973年   1篇
  1972年   1篇
  1971年   5篇
  1967年   4篇
  1966年   2篇
  1965年   1篇
  1964年   2篇
  1963年   1篇
  1954年   1篇
排序方式: 共有477条查询结果,搜索用时 12 毫秒
11.
12.
13.
Conformal radiation therapy for liver metastasis of esophageal carcinoma   总被引:1,自引:0,他引:1  
Recently, aggressive hepatectomies or hepatic arterial infusion chemotherapy for liver metastasis from gastric or colorectal carcinoma have been performed, and the number of successful studies of liver metastasis have increased. However, there have been few successful cases of liver metastasis from esophageal carcinoma by surgery or chemotherapy. Herein, we show the benefits of radiation therapy for the treatment of liver metastasis from esophageal carcinoma. A 60-year-old woman with a 5-cm solitary liver metastasis from esophageal squamous cell carcinoma was treated with radiation therapy. The treated volume was encompassed by the anteroposterior and right lateral opposing fields, shaped by a multileaf collimator. The daily fraction size was 1.8 Gy, 5 days per week, for a total dose of 54 Gy. During the course of treatment, the patient did not experience any complications. After radiotherapy, abdominal computed tomography showed that the enhanced solid tumor had changed to a very low-density mass lesion with a clear margin, and the size was decreasing gradually between the 6 months. Radiotherapy could be a treatment of choice in patients with liver metastasis from esophageal squamous cell carcinoma.  相似文献   
14.
Plasma bradykinin and prostaglandin metabolism are related to the anginal pain modulating system in patients with ischemic heart disease. We carried out a placebo controlled single blind test of diltiazem (30 mg three times a day) in 15 patients with chronic stable angina. The effect of diltiazem was evaluated by exercise treadmill testing and 48-h ambulatory electrocardiographic monitoring. Plasma bradykinin, thromboxane B2, and 6-keto-prostaglandin F1 alpha levels were determined by radioimmunoassay prior to and during diltiazem therapy. Diltiazem significantly increased the exercise time and reduced episodes of angina. Diltiazem, however, did not appreciably improve either the frequency of silent myocardial ischemic episodes or the total duration of the silent myocardial ischemic episodes. Diltiazem also tended to decrease plasma bradykinin, thromboxane B2, and 6-keto-prostaglandin F1 alpha levels. When ischemic episodes on ambulatory electrocardiographic monitoring are categorized according to heart rate change at the onset of episode (type A, preceded by heart rate increase > or = 5 beats/min; type B, no preceding heart rate increase), diltiazem was only effective on type A ischemic episodes as well as on symptomatic ischemia. Further, bradykinin was significantly decreased by diltiazem only in patients with exercise-induced silent ischemia or no exercise-induced ischemia, while the thromboxane B2/6-keto-prostaglandin F1 alpha ratio was unaffected by the administration of diltiazem. Thus, silent and symptomatic ischemia may be associated with different bradykinin and prostaglandin responses.  相似文献   
15.
16.
Immune checkpoint inhibitors (ICIs) have dramatically changed the strategy used to treat patients with non‐small‐cell lung cancer (NSCLC); however, the vast majority of patients eventually develop progressive disease (PD) and acquire resistance to ICIs. Some patients experience oligoprogressive disease. Few retrospective studies have evaluated clinical efficacy in patients with oligometastatic progression who received local therapy after ICI treatment. We conducted a retrospective analysis of advanced NSCLC patients who received PD‐1 inhibitor monotherapy with nivolumab or pembrolizumab to evaluate the effects of ICIs on the patterns of progression and the efficacy of local therapy for oligoprogressive disease. Of the 307 patients treated with ICIs, 148 were evaluated in our study; 42 were treated with pembrolizumab, and 106 were treated with nivolumab. Thirty‐eight patients showed oligoprogression. Male sex, a lack of driver mutations, and smoking history were significantly correlated with the risk of oligoprogression. Primary lesions were most frequently detected at oligoprogression sites (15 patients), and 6 patients experienced abdominal lymph node (LN) oligoprogression. Four patients showed evidence of new abdominal LN oligometastases. There was no significant difference in overall survival (OS) between the local therapy group and the switch therapy group (reached vs. not reached, P = .456). We summarized clinical data on the response of oligoprogressive NSCLC to ICI therapy. The results may help to elucidate the causes of ICI resistance and indicate that the use of local therapy as the initial treatment in this setting is feasible treatment option.  相似文献   
17.
Background and Aim: As bacterial resistance to clarithromycin limits the efficacy of clarithromycin‐based regimens for Helicobacter pylori infection, attention has turned to quinolone‐based rescue therapies. Resistance of H. pylori to both clarithromycin and quinolone can be predicted by genetic testing. Here, we used this approach to evaluate the prevalence of clarithromycin‐ and quinolone‐resistant strains of H. pylori in Japan. Methods: DNA was extracted from gastric tissue samples obtained from 153 patients infected with H. pylori (103 naive for eradication therapy and 50 with previous eradication failure following triple proton pump inhibitor/amoxicillin/clarithromycin therapy). Mutations in H. pylori 23S rRNA and gyrA genes associated with resistance to clarithromycin and quinolones, respectively, were determined. Results: Of 153 patients, 85 (55.6%) were infected with clarithromycin‐resistant strains. The prevalence of clarithromycin‐resistant strains in patients with previous eradication failure (90.0%, 45/50) was significantly higher than that (38.8%, 40/103) of those naive for eradication therapy (P < 0.001). Fifty‐nine patients (38.6%) were infected with strains resistant to quinolones. The incidence of quinolone‐resistant strains also appeared higher in patients with eradication failure (48.0%, 24/50) than in those who had not undergone therapy (34.0%, 35/103); however, the difference was not statistically significant (P = 0.112). The incidence of quinolone‐resistance in clarithromycin‐resistant strains (44/85, 51.8%) was significantly higher than that in clarithromycin‐sensitive strains (15/68, 22.1%) (P < 0.001). Conclusions: A high incidence of quinolone‐resistance was found in clarithromycin‐resistant strains of H. pylori, particularly in patients with previous eradication failure. Our results suggest that testing for susceptibility of H. pylori to quinolones is useful for determining the optimal rescue eradication regimen.  相似文献   
18.

Objectives

The purpose of this study was to investigate factors associated with lymph node (LN) metastasis to identify which nasopharyngeal cancer (NPC) patients can undergo a reduction in the prophylactic radiation field. MRI of biopsy-proven NPC patients was evaluated to determine primary tumour extension and the existence of LN metastasis.

Methods

Sex, age, pathological type, T stage, primary tumour size, existence beyond the midline of the nasopharynx at the primary site and parapharyngeal extension of the primary tumour were assessed regarding their impact on the laterality of LN metastasis using the χ2 test.

Results

Of the 167 patients, 149 (89%) showed nodal involvement. The existence beyond the midline of the nasopharynx was significantly associated with the laterality of LN metastasis (p<0.0001). Most patients (82%) with primary tumour presence within the midline showed only ipsilateral LN metastasis or no LN metastasis. In addition, contralateral LN metastases were seen only at Level II and the retropharyngeal LN among most of other patients.

Conclusion

These results suggest that LN areas other than Level II and the retropharyngeal LN on the contralateral side could be omitted in patients with primary tumour presence within the midline and without the contralateral Level II or the retropharyngeal LN. Whether disease control is compromised by reducing the radiation field for subclinical diseases is a problem that should be solved in the future by prospective study.Most patients with nasopharyngeal cancer (NPC) show cervical lymph node (LN) metastasis at the time of diagnosis, and the frequency is reported to be approximately 90% [1-3]. Some investigators have attributed the high frequency of LN metastasis to the abundance of lymphatic tissues in the posterior wall of the nasopharynx [4, 5]. In view of this fact, the bilateral cervical LN area has usually been included in the clinical target volume (CTV) on definitive radiotherapy (RT) for NPC [6, 7]. However, while NPC may occur at any age, it has a bimodal distribution with the first peak of occurrence in the 15–25 years age range [8]. There is concern that the radiation-induced second primary cancer or late complications such as carotid artery stenosis might increase in the future with an improvement of long-term survival outcome by advancements in therapy such as intensity-modulated radiotherapy (IMRT) or a new promising chemotherapy regimen in younger generations [9-11]. Moreover, mucositis due to a wide irradiation field is still a serious problem during the period of RT, even when RT alone is performed. Thus, it should be sufficiently addressed whether the adequate coverage of the entire bilateral cervical LN area in the CTV for potential subclinical diseases is absolutely necessary for all NPC patients or not.IMRT has been increasingly used in the clinic and has shown clinical benefit in patients with head and neck cancer such as NPC. The optimal definition and the precise delineation of the CTV are absolutely necessary for IMRT, and those provide adequate coverage of the CTV while limiting the dose to the surrounding organs at risk (OAR). We have evaluated the relationship between tumour growth patterns and LN metastasis based on MRI in NPC patients [12, 13]. Our hypothesis of the current study is that if we could show the difference of frequency and regions of cervical LN metastasis according to patient and tumour characteristics, we could reduce the CTV for potential subclinical diseases in selected NPC patients. The present paper reports on the correlation between the laterality and regions of nodal metastasis and the characteristics of the patients and tumours in NPC patients by employing MRI, and pursues the possibility of the reduction of the cervical radiation field in selected patients.  相似文献   
19.
When nedaplatin (NDP) was used as a single agent in the phase I study, the dose-limiting toxicity (DLT) was thrombocytopenia and the recommended dose (RD) was 100 mg/m2. However, the DLT, maximum tolerated dose (MTD) and RD of NDP used in combination with 5-fluorouracil remained unknown. Therefore, we performed this study to assess the DLT and RD of NDP administered after 5-fluorouracil (5-FU). In this study, 5-FU was administered to 38 patients at a fixed dose (700 mg/m2/d on days 1-5) and NDP administered on day 6 at an initial dose of 80 mg/m2, which was subsequently increased to 100, 120, 130, 140, 150, and 160 mg/m2. The DLT of NDP was leukopenia and its MTD and RD were 160 and 150 mg/m2, respectively. Concerning impairment of renal function, only two patients had a grade I increase in serum creatinine. There were 19 responders (50%, 19/38) achieving partial response or complete response in the evaluation of antitumor effect. The result of this study is notable in that administration of 5-FU before NDP allows the dose of NDP to be substantially increased.  相似文献   
20.
We report herein a case of spindle cell type hepatocellular carcinoma responding to hepatic intra-arterial infusion chemotherapy. A 50-year-old woman was hospitalized for right epigastralgia. A computed tomography scan demonstrated cloudy liver tumor with a diameter of 12 cm in S5 and S8. Surgery was performed based on the diagnosis of liver tumor. However, because the tumor was also present in the left lobe, we did only a biopsy for a part of tumor. From the pathological findings, this was diagnosed as a spindle cell type hepatocellular carcinoma. After the operation, hepatic intra-arterial injection therapy of continuous infusion with 5-FU was conducted for two weeks. A small reduction in the tumor was seen with computed tomography after the completion of two courses.  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