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   1797篇
  免费   85篇
  国内免费   16篇
耳鼻咽喉   13篇
儿科学   32篇
妇产科学   53篇
基础医学   229篇
口腔科学   31篇
临床医学   212篇
内科学   327篇
皮肤病学   9篇
神经病学   187篇
特种医学   84篇
外科学   249篇
综合类   43篇
预防医学   157篇
眼科学   29篇
药学   121篇
中国医学   4篇
肿瘤学   118篇
  2023年   15篇
  2022年   22篇
  2021年   34篇
  2020年   28篇
  2019年   37篇
  2018年   33篇
  2017年   24篇
  2016年   32篇
  2015年   34篇
  2014年   57篇
  2013年   75篇
  2012年   101篇
  2011年   129篇
  2010年   71篇
  2009年   56篇
  2008年   89篇
  2007年   108篇
  2006年   102篇
  2005年   85篇
  2004年   93篇
  2003年   78篇
  2002年   71篇
  2001年   46篇
  2000年   44篇
  1999年   55篇
  1998年   17篇
  1997年   20篇
  1996年   15篇
  1995年   13篇
  1994年   14篇
  1992年   15篇
  1991年   20篇
  1990年   27篇
  1989年   18篇
  1988年   18篇
  1987年   19篇
  1986年   15篇
  1985年   12篇
  1984年   11篇
  1983年   19篇
  1981年   8篇
  1979年   9篇
  1978年   7篇
  1977年   12篇
  1975年   9篇
  1973年   6篇
  1972年   8篇
  1970年   6篇
  1968年   8篇
  1966年   7篇
排序方式: 共有1898条查询结果,搜索用时 15 毫秒
1.
Objectives: Currently in Ghana, there is an on-going task-shifting strategy in which nurses are trained in hypertension management. While this study will provide useful information on the viability of this approach, it is not clear how patients in the intervention perceive hypertension, the task-shifting strategy, and its effects on blood pressure management. The objective of this paper is to examine patients’ perceptions of hypertension and hypertension management in the context of an on-going task-shifting intervention to manage blood pressure control in Ghana.

Design: Forty-two patients participating in the Task Shifting Strategy for Hypertension program (23 males, 19 females, and mean age 61. 7 years) completed in-depth, qualitative interviews. Interviews were transcribed, and key words and phrases were extracted and coded using the PEN-3 Cultural Model as a guide through open and axial coding techniques, thus allowing rich exploration of the data.

Results: Emergent themes included patients’ perceptions of hypertension, which encompassed misperceptions of hypertension and blood pressure control. Additional themes included enablers and barriers to hypertension management, and how the intervention nurtured lifestyle change associated with blood pressure control. Primary enabling factors included the supportive nature of TASSH nurses, while notable barriers were financial constraints and difficulty accessing medication. Nurturing factors included the motivational interviewing and patient counseling which instilled confidence in the patients that they could make lasting behavior changes.

Conclusions: This study offers a unique perspective of blood pressure control by examining how patients view an on-going task-shifting initiative for hypertension management. The results of this study shed light on factors that can help and hinder individuals in low-resource settings with long-term blood pressure management.  相似文献   

2.
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment.  相似文献   
3.
4.
5.
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo.  相似文献   
6.
7.
The basis for the antitumor activities of the exocyclic amino nucleosides 4-amino-(ARPP) and 4-methoxy-8-(D-ribofuranosylamino)pyrimido[5,4-d]pyrimidine (MRPP) was investigated. The primary target of these nucleosides appeared to be 5-phospho-alpha-D-ribofuranose-1-pyrophosphate (PRPP) synthetase. MRPP-5'-monophosphate was a competitive inhibitor (Ki = 40 microM) of the activation of this enzyme by the cofactor inorganic phosphate (K alpha = 2.2 mM). Consequently, ARPP and MRPP treatment of WI-L2 cultures rapidly inhibited both de novo pyrimidine and purine synthesis as well as the nucleotide salvage reactions dependent on PRPP, ARPP or MRPP treatment completely prevented [14C]bicarbonate incorporation into acid-soluble pyrimidine and purine nucleotides. The rate of salvage of [8-14C]hypoxanthine to form IMP was decreased by 85%. Treatment of cells with these agents caused a 50% reduction in the steady-state level of PRPP. When the capacity of the treated cells for sustained synthesis of PRPP was examined by adenine incorporation, the rate of adenine uptake was inhibited by greater than 50%. In vivo treatment of BDF1 mice with a single dose of ARPP (173 mg/kg) or MRPP (62 mg/kg) extended the mean life span of the mice, which had been inoculated intraperitoneally 1 day earlier with 1 x 10(6) L1210 murine leukemia cells, by 62 and 82% respectively. These studies indicate that MRPP and ARPP inhibit PRPP synthetase, and that PRPP synthetase may be a viable target in the development of certain antitumor agents.  相似文献   
8.
BACKGROUND: Acute rejection commonly occurs within the first year after heart transplantation, and then decreases in frequency with time. Recently, the long-term utility of endomyocardial biopsy during routine annual catheterization has been questioned. The purpose of this study was to retrospectively review the prevalence of biopsy-proven rejection during routine annual catheterization in our patient population, determine whether biopsies late after transplant are useful, and identify factors that correlate with late unsuspected rejection. METHODS: Biopsy results from the annual catheterization were evaluated from 1986 to August 2000. The prevalence of moderate rejection was evaluated and compared with the patient's immunosuppressive regimen; the prevalence of late rejection; and how late rejection correlated with recipient age, number of first-year rejections and presence of sub-therapeutic cyclosporine. RESULTS: A total of 1108 biopsies were performed in 269 children with a mean follow-up of 5 +/- 3 years (median 5 years, range 1 to 11 years). Three-drug immunosuppressive therapy, including steroids, was used in 93 patients. There was a persistent 8% to 10% prevalence of moderate rejection at up to 10 years post-transplantation. Moderate rejection was more likely in patients: (1). on 3-drug immunosuppressive therapy; (2). with a recipient age >1 year; and (3). with a relatively lower cyclosporine level. CONCLUSIONS: These data suggest that continued surveillance of pediatric transplant patients for acute rejection is indicated for long-term follow-up.  相似文献   
9.
10.
Prosopagnosia is currently viewed within the constraints of two competing theories of face recognition, one highlighting the analysis of features, the other focusing on configural processing of the whole face. This study investigated the role of feature analysis versus whole face configural processing in the recognition of facial expression. A prosopagnosic patient, SC made expression decisions from whole and incomplete (eyes-only and mouth-only) faces where features had been obscured. SC was impaired at recognizing some (e.g., anger, sadness, and fear), but not all (e.g., happiness) emotional expressions from the whole face. Analyses of his performance on incomplete faces indicated that his recognition of some expressions actually improved relative to his performance on the whole face condition. We argue that in SC interference from damaged configural processes seem to override an intact ability to utilize part-based or local feature cues.  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