全文获取类型
收费全文 | 8334篇 |
免费 | 887篇 |
国内免费 | 191篇 |
专业分类
耳鼻咽喉 | 40篇 |
儿科学 | 194篇 |
妇产科学 | 77篇 |
基础医学 | 554篇 |
口腔科学 | 105篇 |
临床医学 | 1897篇 |
内科学 | 1365篇 |
皮肤病学 | 93篇 |
神经病学 | 372篇 |
特种医学 | 240篇 |
外科学 | 807篇 |
综合类 | 713篇 |
一般理论 | 2篇 |
预防医学 | 1029篇 |
眼科学 | 124篇 |
药学 | 1119篇 |
18篇 | |
中国医学 | 444篇 |
肿瘤学 | 219篇 |
出版年
2024年 | 20篇 |
2023年 | 264篇 |
2022年 | 227篇 |
2021年 | 556篇 |
2020年 | 512篇 |
2019年 | 459篇 |
2018年 | 435篇 |
2017年 | 392篇 |
2016年 | 321篇 |
2015年 | 355篇 |
2014年 | 520篇 |
2013年 | 608篇 |
2012年 | 422篇 |
2011年 | 489篇 |
2010年 | 346篇 |
2009年 | 359篇 |
2008年 | 365篇 |
2007年 | 358篇 |
2006年 | 348篇 |
2005年 | 265篇 |
2004年 | 246篇 |
2003年 | 200篇 |
2002年 | 153篇 |
2001年 | 162篇 |
2000年 | 144篇 |
1999年 | 137篇 |
1998年 | 87篇 |
1997年 | 81篇 |
1996年 | 57篇 |
1995年 | 77篇 |
1994年 | 44篇 |
1993年 | 42篇 |
1992年 | 30篇 |
1991年 | 31篇 |
1990年 | 32篇 |
1989年 | 23篇 |
1988年 | 20篇 |
1987年 | 20篇 |
1986年 | 16篇 |
1985年 | 37篇 |
1984年 | 28篇 |
1983年 | 18篇 |
1982年 | 20篇 |
1981年 | 26篇 |
1980年 | 16篇 |
1979年 | 14篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1975年 | 3篇 |
1973年 | 4篇 |
排序方式: 共有9412条查询结果,搜索用时 103 毫秒
21.
目的 探讨临床胜任力为导向的病例教学(case-based learning,CBL)在急危重症护理学本科教学中的可行性和有效性。方法 将急危重症护理本科生120人随机分为CBL教学组和传统教学组。根据每次实习学生人数,CBL教学组分为数个小组,每小组固定一个带教教师,并以小组为单位进行临床教学实践;传统教学组采用既往的临床实习教学方式,即一个学生固定跟随一个带教教师。采用理论考试、技能考试以及问卷调查等多种考核方式评价两组的教学效果,采用SPSS 21.0软件行t检验和卡方检验。结果 与传统教学组相比,CBL教学组在理论考试[(92.5±3.0) vs. (85.3±3.3)]和技能考试[(93.1±4.5) vs. (88.1±3.4)]方面均更好,且差异有统计学意义(P<0.05);在对教学满意度调查方面,CBL教学组优于传统教学组。结论 以临床胜任力为导向的CBL教学应用于急危重症护理本科教学是可行的,能有效培养学生的临床思维和提高实际的临床胜任力。 相似文献
22.
《Journal of infection and chemotherapy》2019,25(6):470-472
We herein report a case of Klebsiella pneumoniae (K. pneumoniae) spondylitis and bacteremia in a 90-year-old man with diabetes mellitus who had undergone sigmoidectomy and had a fecalith. Two months prior to admission, he had received antimicrobial treatment for 2 weeks for K. pneumoniae bacteremia whose entry was unclear and he was readmitted to our hospital owing to fever and stomachache. K. pneumoniae was isolated from two sets of blood cultures, and computed tomography and magnetic resonance imaging revealed inflammation and destruction of the 8th and 9th thoracic vertebra. The diagnosis was spondylodiscitis secondary to K. pneumoniae bacteremia. Although the entry point for K. pneumoniae was unclear, we suggest that inflammation of the mucosa around the fecalith might have caused the Enterobacteriaceae bacteremia. 相似文献
23.
24.
研究了凉粉草胶多糖在20-40℃之间特性粘度对温度的敏感性,计算得其稀溶液的临界线团交叠值C^*[η]平均为1.13,半稀释区斜率b为0.8~1.2,与其他多糖进行了比较。结果表明:凉粉草胶多糖的特性粘度在所测温度区域内的变化不敏感;凉粉草胶多糖在水溶液中,分子链构象可能为刚性杆状结构。 相似文献
25.
In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain. 相似文献
26.
目的:探讨早期干预对高危儿在婴儿早期发育的影响。方法:采用自行设计的一套早期干预方法通过指导家长对实验组实施,分别在3个月、6个月时进行格体生长和行为发育的评估,另设对照组进行比较。结果:实验组和对照组在体重、身长、头围方面均无统计学差异,但实验组的5个能区行为发育商均值都高于对照组,除3个月的语言能区外,其余均有统计学差异。结论:早期干预在婴儿早期就能促进高危儿的行为发育,但对促进高危儿的体格生长无明显效果。 相似文献
27.
Allergen content in dust from homes and schools in northern Norway in relation to sensitization and allergy symptoms in schoolchildren 总被引:2,自引:0,他引:2
L. K. DOTTERUD T. D. VAN B. KVAMMEN† T. DYBENDAL‡ S. ELSAYED E. S. FALK 《Clinical and experimental allergy》1997,27(3):252-261
Background Previous studies have shown a high prevalence of atopic diseases among school children in the community of Sør-Varanger. Moreover, animal dander followed by pollen und house dust mite, were the most common allergens in skin prick tests. Objective To assess the allergen content in homes (living-rooms and mattresses) and classrooms of children living in an arctic area at 70° north. The presence of allergens in homes and schools and their relationship to atopy was of particular interest. Methods Dust samples from 38 homes and seven schools in northern Norway were collected by vacuum cleaning. The presence of allergens of dog, birch, timothy, Cladosporium herbanun, codfish and hen egg-white was investigated by radio-allergosorbent test (RAST) inhibition and the presence of major allergens of cat Felis domesticus (Fel d I) and house dust mites (HDM) Dermatophagoides pteronyssinus (Derp I) and Dermatophagoides farinae (Derf I) by enzyme-linked immunosorbent assay (ELISA). Results Mattresses contained significantly more dust per unit area than living-rooms and classrooms. No statistically significant differences in allergen content for dog. birch, timothy, Cladosporium, codfish and hen egg-white were seen between HDM-sensitized and non-atopic children. Most dust samples contained dog allergens with the highest allergenic activity found in living-rooms of those keeping dogs. An increased level of Feld I was detected in only one of 38 samples from living-rooms (this family kept a cat) and in 25 of 38 samples from mattresses with ranges from 24 to 84ng/m2. The highest concentrations were found in mattresses of children keeping cats. Increased levels ( 25 ng/m2) of Derp I were found only in homes and virtually only in mattresses of HDM-sensitized children. An increased level of Derf] was found in only one case, i.e. in the mattress of an HDM-sensitized child where additionally Der p I and HDMs were demonstrated microscopically. When relating Der p I to HDMsensitization an odds ratio of more than 16 (95% Cl: 1.6–394.3) was found. All extracts from living-rooms included codfish allergens. Low RAST inhibition values were detected for hen egg-white, Cladosporium, birch and timothy pollen in most samples. Furthermore, the study demonstrated that dust from schools was relatively free of allergens. Conclusion Previous findings indicating that the main allergen exposure problem in this geographical area is that of pet allergens were confirmed. 相似文献
28.
[目的 ]探讨人工气道气囊压力监测在老年危重病人气管导管护理中的应用价值。 [方法 ]将 60例建立人工气道的老年危重病人随机分成两组 ,实验组应用PORTEX专用气囊压力监测表注气测压 ,对照组采用传统的手指捏感法注气 ;用呼吸机检查漏气情况 ,并比较两组病人的气囊注气容积、气囊压力及并发症发生率。 [结果 ]实验组气囊压力为 2 .45 2kPa±0 .490kPa时 ,气囊容积为 10 .0mL± 4.7mL ,呼吸机检查不漏气 ;对照组气囊压力为 3 .92 3kPa± 0 .73 6kPa时 ,气囊容积为 15 .0mL± 5 .1mL ,呼吸机检查不漏气。两组病人气管黏膜损伤、气囊破裂发生率比较有统计学意义 (P <0 .0 5 ) ;两组病人误吸、食管气管瘘发生率比较无统计学意义 (P >0 .0 5 )。 [结论 ]建立人工气道的老年危重病人气囊压力维持在1.961kPa~ 2 .942kPa ,能有效避免误吸的发生和气管黏膜的损伤。 相似文献
29.
Myelination of the corpus callosum in the cat: time course, topography, and functional implications 总被引:1,自引:0,他引:1
The parameters of myelin development were ascertained in two specific regions of the corpus callosum in a series of cats aged 12 postnatal days through adult. The posteriormost portion of the splenium and the anterior-most portion of the genu were examined in cross section by using the electron microscope. Measurements were made to determine the age at which myelin first appeared, the number and distribution of myelinated fibers, the number and distribution of myelin lamellae, and cross-sectional area of ensheathed axons during development. The results indicate that myelination begins and ends earlier in the anterior region of the callosum. Measurements of myelin lamellae indicate similarities between anterior and posterior regions of the callosum, although development occurs earlier in the genu than in the splenium. No evidence was found for a sequence in the size of axons acquiring myelin sheaths, except that extremely small fibers are the last to begin myelinating. Myelination of the splenium of the corpus callosum begins at the very end of the behavioral and physiological critical period for the corpus callosum's role in visual functional development (Elberger: Behav. Brain Res. 11:223-231, '84; Elberger and Smith: Exp. Brain Res. 57:213-223, '85). Since myelination of a pathway is used as an index of functional reliability, this indicates that the basis for the callosal role in developing visual functions is probably not based on its physiological input to visual cortex. 相似文献
30.
目的 对比分析食管癌病例组与对照组血缘亲属食管癌患病风险,并了解食管癌家族中危险亲属人群患病的新线索.方法 采用病例对照研究方法 ,对食管癌病例组及对照组各720例进行逐层分析,以比较两组各血缘亲属父系、母系食管癌患病危险度(OR)的大小及差异.结果 (1)病例组Ⅰ级亲属食管癌患病危险度(1.34%~2.24%)显著高于对照组(0.78%~1.21%)(P<0.01);Ⅰ级亲属中病例组父母亲食管癌患病危险度为6.11%,显著高于对照组父母亲食管癌患病危险度2.97%(P<0O01).(2)以血缘亲属中父系和母系亲属逐层分析可见,病例组父系食管癌患病危险度(0.87%~1.01%)与母系患病危险度(0.50%~0.79%)均显著高于对照组父系食管癌患病危险度(0.53%~0.65%)与母系患病危险度(0.38%~0.47%)(P<0.05).进一步分析显示,病例组父系中男性亲属与母系中女性亲属,即父系中祖父、父亲、叔伯食管癌患病危险度为2.68%与母系中外祖母、母亲、姨的食管癌患病危险度1.91%均显著高于对照组父系中男性亲属食管癌患病危险度1.50%与母系中女性亲属食管癌患病危险度0.92%(P<0.01).结论 山西省食管癌患者血缘亲属发病危险主要是父亲及其兄弟、母亲及其姐妹,其下代患食管癌风险要大. 相似文献