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   11439篇
  免费   510篇
  国内免费   170篇
耳鼻咽喉   129篇
儿科学   101篇
妇产科学   34篇
基础医学   1485篇
口腔科学   217篇
临床医学   575篇
内科学   807篇
皮肤病学   49篇
神经病学   890篇
特种医学   273篇
外科学   664篇
综合类   1381篇
预防医学   581篇
眼科学   1740篇
药学   2637篇
  3篇
中国医学   385篇
肿瘤学   168篇
  2023年   138篇
  2022年   207篇
  2021年   287篇
  2020年   253篇
  2019年   385篇
  2018年   402篇
  2017年   313篇
  2016年   298篇
  2015年   259篇
  2014年   652篇
  2013年   752篇
  2012年   635篇
  2011年   671篇
  2010年   531篇
  2009年   597篇
  2008年   477篇
  2007年   510篇
  2006年   459篇
  2005年   441篇
  2004年   345篇
  2003年   265篇
  2002年   245篇
  2001年   234篇
  2000年   238篇
  1999年   211篇
  1998年   152篇
  1997年   159篇
  1996年   109篇
  1995年   116篇
  1994年   131篇
  1993年   90篇
  1992年   109篇
  1991年   114篇
  1990年   91篇
  1989年   108篇
  1988年   85篇
  1987年   80篇
  1986年   78篇
  1985年   110篇
  1984年   88篇
  1983年   56篇
  1982年   76篇
  1981年   65篇
  1980年   53篇
  1979年   109篇
  1978年   37篇
  1977年   41篇
  1976年   43篇
  1974年   32篇
  1973年   49篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
目的 探讨孕康颗粒联合阿司匹林及低分子肝素钠治疗复发性流产的临床疗效。方法 选取2019年1月—2020年6月于河南省生殖妇产医院就诊的108例复发性流产患者为研究对象,随机分为对照组和治疗组,每组各54例。对照组口服阿司匹林肠溶片,100 mg/次,1次/d,同时皮下注射低分子肝素钠注射液,3 200 IU/次,1次/d。治疗组在对照组基础上口服孕康颗粒,1袋/次,3次/d。两组患者均连续治疗10周。观察两组患者临床疗效,比较治疗前后两组患者激素雌二醇(E2)、孕酮(P)和人绒毛膜促性腺激素(HCG)水平,凝血-纤溶系统指标凝血酶原时间(PT)、活化部分凝血酶原时间(APTT)、血清纤溶酶原激活抑制剂1(PAI-1)水平和组织型纤溶酶原激活剂(t-PA),细胞因子白细胞介素-17(IL-17)、白细胞介素-23(IL-23)、转化生长因子-β(TGF-β)和白细胞介素-10(IL-10)水平。结果 治疗后,与对照组相比,治疗组临床有效率显著升高,差异具有统计学意义(P<0.05)。治疗后,两组E2、P及HCG、PT、APTT及TGF-β和IL-10水平均显著升高(P<0.05),而IL-17、PAI-1和IL-23水平显著降低(P<0.05),且治疗组这些指标水平明显好于对照组(P<0.05)。结论 孕康颗粒联合阿司匹林及低分子肝素钠治疗复发性流产的临床疗效显著且安全性高,其中机制可能与改善复发性流产患者的激素水平、凝血-纤溶系统及调节Th17/Treg细胞失衡有关。  相似文献   
2.
目的 探讨健康受试者参加华法林钠片生物等效性试验的安全性。方法 收集2017—2020在首都医科大学宣武医院开展的4项随机、开放、四周期、交叉对照设计的华法林钠片生物等效性(BE)试验中188例受试者,比较空腹与餐后给药所发生不良事件(TEAEs)的差异及TEAEs与性别和年龄的相关性。结果 4个试验中共报告了116例次TEAEs,与试验药物相关的TEAEs 29例次,均属于轻度,主要为凝血功能指标异常(14例次)和肝功能指标异常(10例次)。餐后给药试验中肝功能指标异常的发生例次多于空腹给药试验(8:2),与试验药物具有相关性的TEAEs发生率出现随年龄增加而增高的趋势。结论 健康受试者参加BE试验单次口服华法林钠片的安全性良好,与试验药物相关的不良事件多与华法林的药理机制有关,年龄是不良事件发生类型和发生率的潜在影响因素。  相似文献   
3.
4.
《Cancer radiothérapie》2022,26(8):1016-1026
PurposeRadiotherapy with protons (PT) is a standard treatment of ocular tumors. It achieves excellent tumor control, limited toxicities, and the preservation of important functional outcomes, such as vision. Although PT may appear as one homogenous technique, it can be performed using dedicated ocular passive scattering PT or, increasingly, Pencil Beam Scanning (PBS), both with various degrees of patient-oriented customization.Materaial and methodsMEDICYC PT facility of Nice are detailed with respect to their technical, dosimetric, microdosimetric and radiobiological, patient and tumor-customization process of PT planning and delivery that are key. 6684 patients have been treated for ocular tumors (1991–2020). Machine characteristics (accelerator, beam line, beam monitoring) allow efficient proton extraction, high dose rate, sharp lateral and distal penumbrae, and limited stray radiation in comparison to beam energy reduction and subsequent straggling with high-energy PBS PT. Patient preparation before PT includes customized setup and image-guidance, CT-based planning, and ocular PT software modelling of the patient eye with integration of beam modifiers. Clinical reports have shown excellent tumor control rates (~95%), vision preservation and limited toxicity rates (papillopathy, retinopathy, neovascular glaucoma, dry eye, madarosis, cataract).ResultsAlthough demanding, dedicated ocular PT has proven its efficiency in achieving excellent tumor control, OAR sparing and patient radioprotection. It is therefore worth adaptations of the equipments and practice.ConclusionsSome of these adaptations can be transferred to other PT centers and should be acknowledeged when using non-PT options.  相似文献   
5.
目的:基于丙戊酸钠的体内代谢过程具有显著的年龄发育特征,本研究旨在考察不同年龄段儿童癫痫患者使用丙戊酸钠后的稳态血药浓度特征及其与癫痫控制情况、药品不良反应(ADR)之间的关联,以此获得丙戊酸钠在儿科使用的安全性和有效性数据。方法:纳入2017年1月至2020年6月该院神经科确诊为癫痫并使用丙戊酸钠的患儿748例,采集其口服给药3 d后的清晨空腹静脉血,检测血浆中丙戊酸钠浓度并记录其癫痫发作频率,神经系统、胃肠道和皮肤方面的ADR发生情况。结果:丙戊酸钠的稳态血药浓度随年龄呈现显著的阶梯式升高特征,<1岁癫痫患儿的丙戊酸钠平均血药浓度为(50.06±28.18)mg/L;1~2岁患儿为(51.08±18.71)mg/L;>2~6岁患儿为(59.87±22.07)mg/L,显著高于1~2岁患儿,差异有统计学意义(P<0.05);>6~14岁患儿为(63.23±26.67)mg/L,高于>2~6岁患儿,但差异无统计学意义(P>0.05),明显高于1~2岁患儿(P<0.001)和<1岁患儿(P<0.01),差异均有统计学意义。丙戊酸钠低剂量组患儿[<20 mg/(kg·d)]的稳态血药浓度低于中剂量组[20~30 mg/(kg·d)]、高剂量组[>30 mg/(kg·d)],但是中、高剂量组患儿中丙戊酸钠血药浓度并不呈现剂量相关性。丙戊酸钠中、高血药浓度组患儿的癫痫控制率分别为90.0%(387/430)和91.1%(41/45),显著高于低血药浓度组的70.0%(191/273),差异均有统计学意义(P<0.05)。共收集39例ADR,发生率较高的ADR为神经系统反应(14例)、肝功能受损(11例)和消化系统反应(9例)。ADR发生率随丙戊酸钠血药浓度升高而有升高趋势,且呈年龄相关性,≤2岁的低年龄段癫痫患儿使用丙戊酸钠的ADR发生率显著高于其他年龄段(>2~14岁)癫痫患儿。结论:(1)儿童的丙戊酸钠血药浓度和ADR有年龄段特异性分布特征,婴幼儿(≤2岁)的丙戊酸钠血药浓度易低于最低治疗浓度,但更易发生ADR,在临床用药过程中应注意密切监测;(2)儿童群体血药浓度控制在50~100 mg/L范围内时,丙戊酸钠的安全性和有效性均较为理想;(3)相对于成人,儿童的肝损伤发生率较高,使用丙戊酸钠过程中应加强肝功能指标的监测。  相似文献   
6.
Defects of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein affect the homeostasis of chloride, bicarbonate, sodium, and water in the airway surface liquid, influencing the mucus composition and viscosity, which induces a severe condition of infection and inflammation along the whole life of CF patients. The introduction of CFTR modulators, novel drugs directly intervening to rescue the function of CFTR protein, opens a new era of experimental research. The review summarizes the most recent advancements to understand the characteristics of the infective and inflammatory pathology of CF lungs.  相似文献   
7.
8.
BackgroundThe diatom test method using sodium hypochlorite (NaClO) was equivalent to the conventional method in water samples. However, the method using NaClO was inferior to the conventional method in lung samples, in which ethanol was used and the reaction with NaClO was longer compared with the method in water samples. Using water samples, we aimed to clarify whether these differences affect the diatom test result.Materials and methodsThirteen water samples from natural water sources were each divided into four parts corresponding to four (2 × 2) digestion methods: 3 “digestion” vs. 1 “digestion” and with ethanol vs. without ethanol. After the base-2 logarithmic transformation, the diatom counts were analyzed using three-way analysis of variance (ANOVA); factor 1 was “digestion times,” factor 2 was “ethanol,” and factor 3 was “sample number,” and the interaction between factors 1 and 2 was also analyzed.ResultsThe geometric means of the diatoms from the 3 “digestion” with ethanol method, the 3 “digestion” without ethanol method, the 1 “digestion” with ethanol method, and the 1 “digestion” without ethanol method were 373.5, 551.8, 436.6, and 522.0, respectively. ANOVA showed a significant difference in factor 2 (P = 1.7 × 10-4). There was no significant difference in factor 1 (P = 0.46), and no significant interaction between factors 1 and 2 (P = 0.13).ConclusionEthanol may decrease the diatom count in the diatom test using NaClO. In contrast, the diatom frustules do not dissolve through three-times digestion using NaClO.  相似文献   
9.
目的探讨关节镜清理术联合透明质酸钠治疗膝骨性关节炎患者的效果。方法100例膝骨性关节炎患者随机分为两组各50例,对照组采用关节镜清理术治疗,实验组采用关节镜清理术联合透明质酸钠治疗,比较两组的关节液炎性因子水平、膝关节功能以及疼痛情况。结果治疗后,实验组的TNF-α、IL-6、IL-8水平均显著低于对照组(P<0.05)。治疗1个月、3个月、6个月后,实验组的Lysholm评分均显著高于对照组,VAS评分均显著低于对照组(P<0.05)。结论关节镜清理术联合透明质酸钠治疗膝骨性关节炎可降低患者关节液炎性因子水平,改善膝关节功能,减轻疼痛。  相似文献   
10.
BackgroundTo evaluate the patterns of distribution and clinical manifestations of ocular injuries referred to the level 1 trauma center of Pusan National University Hospital (PNUH) in Korea.MethodsWe analyzed 254 of 4,287 patients who were referred to the Department of Ophthalmology at the level 1 trauma center of the PNUH, from January 2016 through December 2018. Data on the incidence of ocular injuries, sex, age, monthly and seasonal distribution, day and time of injury, side of injury, cause, residence of patients, referral time to an ophthalmologist and subsequent examination time, final visual acuity (VA), and complications were obtained from medical records and retrospectively reviewed. The patients were grouped according to their main diagnosis using the Birmingham Eye Trauma Terminology System (BETTS) and Ocular Trauma Score (OTS).ResultsThe incidence of ocular injuries with major trauma was higher in men (n = 207, 81.5%), the median age at time of injury was 54 years, and Pusan recorded the most cases. The incidences of ocular injury were 1.47/100,000, 1.57/100,000, 1.48/100,000 in 2016, 2017 and 2018, respectively. The most common cause was by a motorbike accident, followed by a pedestrian traffic accident and falls. According to the BETTS classification, open-globe injuries represented 4% of cases, closed-globe injuries represented 12.6%, and other injuries represented 83.1%. Open-globe injuries were significantly associated with low final VA (P = 0.01). In the OTS, 79.4% of patients received 4 or 5 points and 13.7% of patients received 1 or 2 points. The patients who received 1 or 2 points in the OTS score showed final VA below hand movement (P < 0.001), except for two patients. Lid laceration and low initial VA were highly correlated with poor final VA (P < 0.001).ConclusionThis is the first study on the epidemiology and clinical manifestations in trauma patients with ocular injuries at a level 1 trauma center. The incidences of ocular injuries with major trauma were about 1.47–1.57/100,000. BETTS, OTS, lid laceration and initial VA were associated with final VA. We expect our study to provide a basis of data for the evaluation, prevention, and management of ocular injuries in patients with systemic trauma.  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