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   21371篇
  免费   1344篇
  国内免费   475篇
耳鼻咽喉   184篇
儿科学   537篇
妇产科学   185篇
基础医学   2469篇
口腔科学   132篇
临床医学   1614篇
内科学   2869篇
皮肤病学   225篇
神经病学   421篇
特种医学   460篇
外国民族医学   1篇
外科学   1007篇
综合类   2239篇
现状与发展   1篇
一般理论   2篇
预防医学   7030篇
眼科学   63篇
药学   2257篇
  6篇
中国医学   420篇
肿瘤学   1068篇
  2024年   7篇
  2023年   607篇
  2022年   855篇
  2021年   1154篇
  2020年   999篇
  2019年   839篇
  2018年   856篇
  2017年   772篇
  2016年   819篇
  2015年   902篇
  2014年   1396篇
  2013年   1689篇
  2012年   1275篇
  2011年   1434篇
  2010年   1172篇
  2009年   1138篇
  2008年   825篇
  2007年   936篇
  2006年   790篇
  2005年   674篇
  2004年   629篇
  2003年   538篇
  2002年   405篇
  2001年   396篇
  2000年   327篇
  1999年   294篇
  1998年   199篇
  1997年   192篇
  1996年   134篇
  1995年   108篇
  1994年   93篇
  1993年   81篇
  1992年   63篇
  1991年   70篇
  1990年   69篇
  1989年   68篇
  1988年   57篇
  1987年   57篇
  1986年   47篇
  1985年   67篇
  1984年   38篇
  1983年   19篇
  1982年   28篇
  1981年   17篇
  1980年   13篇
  1979年   13篇
  1978年   9篇
  1977年   4篇
  1974年   4篇
  1972年   4篇
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
41.
《Cancer radiothérapie》2020,24(5):388-397
The assessment of tumour response during and after radiotherapy determines the subsequent management of patients (adaptation of treatment plan, monitoring, adjuvant treatment, rescue treatment or palliative care). In addition to its role in extension assessment and therapeutic planning, positron emission tomography combined with computed tomography provides useful functional information for the evaluation of tumour response. The objective of this article is to review published data on positron emission tomography combined with computed tomography as a tool for evaluating external radiotherapy for cancers. Data on positron emission tomography combined with computed tomography scans acquired at different times (during, after initial and after definitive [chemo-]radiotherapy, during post-treatment follow-up) in solid tumours (lung, head and neck, cervix, oesophagus, prostate and rectum) were collected and analysed. Recent recommendations of the National Comprehensive Cancer Network are also reported. Positron emission tomography combined with computed tomography with (18F)-labelled fluorodeoxyglucose has a well-established role in clinical routine after chemoradiotherapy for locally advanced head and neck cancers, particularly to limit the number of neck lymph node dissection. This imaging modality also has a place for the evaluation of initial chemoradiotherapy of oesophageal cancer, including the detection of distant metastases, and for the post-therapeutic evaluation of cervical cancer. Several radiotracers for positron emission tomography combined with computed tomography, such as choline, are also recommended for patients with prostate cancer with biochemical failure. (18F)-fluorodeoxyglucose positron emission tomography combined with computed tomography is optional in many other circumstances and its clinical benefits, possibly in combination with MRI, to assess response to radiotherapy remain a very active area of research.  相似文献   
42.
宫颈癌是影响全球女性健康的公共卫生问题。持续的高危型HPV感染是宫颈癌的主要致病因素。目前,HPV预防性疫苗已经在全球范围内逐渐广泛开展,但其对已感染HPV的女性没有治疗作用。迄今,多种治疗性疫苗已用于临床前模型和临床试验,包括肽和蛋白质疫苗、活载体疫苗、DNA疫苗等,并已经显示出良好的安全性和耐受性,为宫颈癌的防治工作带来了希望和动力。但其仍存在免疫原性低、需要寻找更多新的靶抗原基因等不足,仍需进一步研究。  相似文献   
43.
外泌体是来源于细胞内膜的纳米级的囊泡,包含有核酸、蛋白和脂质等生命物质,作为一种细胞间交流的机制,在生命活动中发挥着重要作用。相对于脂质体载体,外泌体更稳定,生物相容性好,免疫原性低,而且可以渗透生物屏障,例如血脑屏障、胎盘屏障等。重点介绍外泌体载体靶向性的基础、外泌体载体装载负荷的方法及外泌体载体目前的应用进展和前景。  相似文献   
44.

Background

Vaccination of children with 13-valent pneumococcal conjugate vaccine (PCV13) led to declines in vaccine-type pneumococcal nasopharyngeal carriage among adults through indirect effects. In August 2014, PCV13 immunization of all U.S. adults ≥65?years of age was recommended. This study sought to define prevalence and serotype distribution of pneumococcal carriage among adults ≥65?years of age and to describe risk factors for colonization soon after introduction of PCV13 in adults.

Methods

A cross-sectional survey of non-institutionalized U.S. adults ≥65?years of age was conducted in four states in 2015–2016. Demographic information, risk factors for disease, PCV13 vaccination history, and nasopharyngeal (NP) and oropharyngeal (OP) swabs were collected. NP and OP swabs were processed separately and pneumococcal isolates were serotyped by Quellung reaction. Antimicrobial susceptibility of pneumococcal isolates was performed. NP swabs also underwent real-time PCR for pneumococcal detection and serotyping.

Results

Of 2989 participants, 45.3% (1354/2989) had been vaccinated with PCV13. Fifty-five (1.8%) carried pneumococcus (45 identified by culture and 10 by real-time PCR only) and PCV13 serotypes were found in eight (0.3%) participants. Almost half (22/45) of pneumococcal isolates were not susceptible to at least one of the antibiotics tested. Vaccine-type carriage among vaccinated and unvaccinated individuals was similar (0.2% vs. 0.1%, respectively). Respiratory symptoms were associated with higher odds of pneumococcal colonization (adjusted OR: 2.1; 95% CI?=?1.1–3.8).

Conclusions

Pneumococcal carriage among non-institutionalized adults ≥65?years of age was very low. Less than 0.5% of both vaccinated and unvaccinated individuals in our study carried vaccine-type serotypes. Over a decade of PCV vaccination of children likely led to indirect effects in adults. However, given the low vaccine-type carriage rates we observed in an already high PCV13 adult coverage setting, it is difficult to attribute our findings to the direct versus indirect effects of PCV13 on adult carriage.  相似文献   
45.

Background

A nasal influenza vaccine has been available only in a live attenuated form, which limits the range of recipients to immune-competent individuals. The present study evaluated a newly developed intranasal inactivated influenza vaccine with a novel adjuvant, heat-labile enterotoxin (LT) derived from E. coli (LTh(αK)).

Methods

The study was a randomized, double-blind, controlled phase I trial to evaluate the safety and immunogenicity of an intranasal vaccine containing the trivalent influenza HA antigen (7.5?µg each of A/California/7/09 (H1N1)-like virus, A/Victoria/210/2009 (H3N2) virus, and B/Brisbane/60/2008-like virus) in combination with 4 different doses of adjuvant LTh(αK) (7.5, 15, 30 or 45?μg) and 22.5?μg of influenza HA antigen alone (control vaccine). The vaccine was intranasally administered on Days 0 and 7. A safety evaluation commenced for 180?days, and hemagglutination inhibition (HI) antibody titers and nasal HA-specific IgA titers on Day 0 and Day 28 were assessed to determine whether an immunogenic response was elicited.

Results

From November 2012 to September 2013, a total of 36 subjects were enrolled. Twenty-four subjects received an adjuvanted vaccine, and 12 subjects received a control vaccine. The most common adverse event (AE) was mild nasal discomfort, and systemic AEs were mild fatigue and headache. Only two subjects discontinued the study because of an AE (one had grade 3 fever, and one had nodal arrhythmia). In the group with 45?μg of LTh(αK), the seroprotection rates were 100%, 100% and 80%, and the nasal IgA conversion factors were 7.90, 7.46 and 12.27 for the A/H3N2, A/H1N1 and split B strains, respectively. Adjuvant LTh(αK) vaccine showed a significant enhancement in mucosal immunity in split B -specific IgA.

Conclusion

The intranasal inactivated influenza vaccine is generally safe, and the LTh(αK)-adjuvanted vaccine is more immunogenic than non-adjuvanted control vaccine.ClinicalTrials.gov Identifier: NCT03293732.  相似文献   
46.
Objectives: There are disparities in the uptake of HPV vaccine among racial/ethnic minority women. The strongest predictor of HPV vaccine uptake among adult women is health care provider (HCP) recommendation; however, it is unclear how issues relating to race/ethnicity may mitigate these recommendations. Research shows that racial/ethnic and gender concordance between a patient and HCP can improve patient satisfaction, access and quality of care. If concordance contributes to improved patient-provider interactions, then it may be a factor in patient decisions regarding HPV vaccination. The objectives of this study were to (1) explore gender and ethnicity HCP preference regarding HPV vaccination among unvaccinated; and (2) understand factors associated with those preferences.

Design: Unvaccinated Latina college students (n?=?187) completed a survey that assessed HCP preferences, medical mistrust, cultural assimilation and HPV vaccine recommendation. Logistic regression models evaluated associations between above variables with HPV knowledge and preference for a female and/or Latina HCP.

Results: Most respondents had health insurance (71%), a regular HCP (64%), were US-born (67%), with foreign-born parents (74%). Thirty-four percent and 18% agreed that they would be more likely to get the HPV vaccine if the recommending HCP was female and Latino, respectively. Latina women reporting higher medical mistrust preferred a HPV vaccine recommendation from a Latino/a provider.

Conclusions: Latinas’ preferences regarding gender and ethnicity of their HCPs may affect patient-provider interactions. Increasing diversity and cultural awareness among HCPs, and providing linguistically and culturally-appropriate information may decrease patient-provider mistrust, increase uptake of the HPV vaccine, and decrease persistent cervical cancer disparities.  相似文献   

47.
B cells are recognized as the main effector cells of humoral immunity which suppress tumor progression by secreting immunoglobulins, promoting T cell response, and killing cancer cells directly. Given these properties, their anti-tumor immune response in the tumor micro-environment (TME) is of great interest. Although T cell-related immune responses have become a therapeutic target with the introduction of immune checkpoint inhibitors, not all patients benefit from these treatments. B cell and B cell-related pathways (CCL19, −21/CCR7 axis and CXCL13/CXCR5 axis) play key roles in activating immune response through humoral immunity and local immune activation via tertiary lymphoid structure (TLS) formation. However they have some protumorigenic works in the TME. Thus, a better understanding of B cell and B cell-related pathways is necessary to develop effective cancer control. In this review, we summarize recent evidences regarding the roles of B cell and B cell-related pathways in the TME and immune response and discuss their potential roles for novel cancer treatment strategies.  相似文献   
48.
Schizophrenia is a chronic mental pathology with polymorphous symptoms that have an invalidating impact on an emotional, interpersonal, behavioural and social level. In certain cases this pathology can increase the risk of self-harm or harm to others, making it necessary to put protocoles in place for specifically-adapted treatment, put forward notably by care units that deal with dangerous patients. The patient's therapeutic education, orientated towards acquiring knowledge about the illness and skills for dealing with it in day-to-day life, is now a recognised practice, having proven its effectiveness in the treatment of chronic psychiatric patients. There is significant interest in this method for treating dangerous mental patients. In this interview, the psychologist Diane Brulin-Solignac shares her knowledge and experience of this therapeutic practice.  相似文献   
49.
Brucellosis is a worldwide bacterial zoonosis caused by Brucella spp. No approved vaccine is available for human use against the disease. In this study, outer membrane vesicles (OMVs) from a Brucella melitensis biovar 1 human isolate obtained in Iran were used to immunize BALB/c mice (n = 12) by 2 intramuscular injections with a 2‐week interval. Another group of 12 mice was used as non‐vaccinated controls. Two weeks after the last vaccination, six mice of each group were sacrificed, and proliferation and interferon gamma (IFNγ) production responses of their splenocytes were evaluated following in vitro stimulation with killed Brucella cells. The other mice were challenged with the virulent B. melitensis isolate. Two weeks later, mice were killed and spleens were cultured to determine the number of the challenge strain. The results showed proliferative response and IFNγ production of splenocytes from vaccinated mice (stimulation index: 2.18 ± 0.57, and 1519.35 ± 10.70 pg/mL, respectively) were significantly higher than those of control mice (stimulation index: 1.02 ± 0.02, and 210.01 ± 17.58 pg/mL, respectively). Numbers of the challenge strain in spleens of vaccinated mice were also significantly less than those in the controls with 1.6 units of protection. Our study revealed vaccination with OMVs of the B. melitensis isolate could induce specific immune responses and protection against infection in the mouse model suggesting their potential application for active immunization against brucellosis.  相似文献   
50.
目的研究肥胖型2型糖尿病患者联合采用西格列汀、二甲双胍治疗的临床效果。方法选择2018年10月—2020年4月该院100例肥胖型2型糖尿病患者为研究对象,采用随机数表法分成常规组和治疗组,每组50例。常规组予二甲双胍治疗,治疗组予二甲双胍+西格列汀治疗。比较两组治疗效果、血糖指标、体脂含量、胰岛功能指标及不良反应。。结果两组治疗效果比较,差异有统计学意义(P<0.05)。治疗后常规组血糖指标高于治疗组,差异有统计学意义(t=8.183、4.828、18.158,P<0.05)。治疗后常规组体脂含量高于治疗组,差异有统计学意义(t=5.993、7.657、4.420,P<0.05)。治疗后两组胰岛功能比较,差异有统计学意义(t=5.898、5.283、16.033,P<0.05)。常规组不良反应总发生率低于治疗组,但差异无统计学意义(χ2=0.136,P=0.712)。结论西格列汀、二甲双胍联合治疗肥胖型2型糖尿病效果确切。  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