全文获取类型
收费全文 | 2218篇 |
免费 | 212篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 74篇 |
妇产科学 | 21篇 |
基础医学 | 201篇 |
口腔科学 | 54篇 |
临床医学 | 228篇 |
内科学 | 350篇 |
皮肤病学 | 36篇 |
神经病学 | 63篇 |
特种医学 | 167篇 |
外科学 | 328篇 |
综合类 | 356篇 |
一般理论 | 1篇 |
预防医学 | 211篇 |
眼科学 | 23篇 |
药学 | 184篇 |
2篇 | |
中国医学 | 77篇 |
肿瘤学 | 101篇 |
出版年
2024年 | 8篇 |
2023年 | 19篇 |
2022年 | 53篇 |
2021年 | 78篇 |
2020年 | 55篇 |
2019年 | 48篇 |
2018年 | 56篇 |
2017年 | 61篇 |
2016年 | 59篇 |
2015年 | 106篇 |
2014年 | 114篇 |
2013年 | 155篇 |
2012年 | 183篇 |
2011年 | 198篇 |
2010年 | 142篇 |
2009年 | 117篇 |
2008年 | 123篇 |
2007年 | 114篇 |
2006年 | 120篇 |
2005年 | 116篇 |
2004年 | 66篇 |
2003年 | 73篇 |
2002年 | 46篇 |
2001年 | 30篇 |
2000年 | 29篇 |
1999年 | 34篇 |
1998年 | 27篇 |
1997年 | 19篇 |
1996年 | 23篇 |
1995年 | 16篇 |
1994年 | 8篇 |
1993年 | 19篇 |
1992年 | 13篇 |
1991年 | 9篇 |
1990年 | 7篇 |
1989年 | 13篇 |
1988年 | 12篇 |
1987年 | 8篇 |
1986年 | 24篇 |
1985年 | 11篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 9篇 |
1975年 | 5篇 |
1974年 | 3篇 |
排序方式: 共有2495条查询结果,搜索用时 31 毫秒
1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。 相似文献
2.
目的 观察优克龙 (Urocalun )治疗输尿管结石的疗效和安全性。 方法 对 6 0例输尿管结石直径 <1cm的患者予口服优克龙治疗 ,4 5 0mg/次 ,3次 /d ,服药 5周。 结果 6 0例患者中结石排出 4 5例 (75 % ) ;10例 (17% )结石位置下降 ;5例 (8% )位置无变化。 4例患者服药后有轻度胃部不适、恶心或口干。 结论 优克龙治疗输尿管结石效果良好。 相似文献
3.
Mary C Tierney W Gary Snow Jocelyn Charles Rahim Moineddin Alex Kiss 《The American journal of geriatric psychiatry》2007,15(2):140-148
OBJECTIVE: The authors examined the accuracy of certain neuropsychological tests in the prediction of harm resulting from self-neglect in cognitively impaired seniors who lived alone. METHODS: The study included 130 participants, aged 65 and older, who scored less than 131 on the Dementia Rating Scale. Neuropsychological tests were administered at baseline, resulting in eight predictive scores. Informants and primary care physicians provided information about harm that occurred to the participants during the 18-month prospective follow up. An incident was defined as harmful if it occurred as the result of self-neglect or disorientation and resulted in physical injury or property loss or damage and required emergency interventions. Proportional hazard regression analysis was conducted to examine the predictive relationship between the eight neuropsychological tests and time to incident harm with age, sex, education, the Charlson Comorbidity Index, and the Mini-Mental State Examination included in the model as covariates. RESULTS: Twenty-seven participants experienced harm during the 18-month follow-up period. A proportional hazards model indicated that three neuropsychological tests, which measured recognition memory, executive functioning, and conceptualization, were independent risk factors for harm. CONCLUSIONS: These findings provide insight into why harm occurred in these cognitively impaired elders who lived alone. They also support the ecologic validity of these tests and suggest directions for the development of intervention strategies for harm prevention. 相似文献
4.
目的 通过彩色多普勒超声心动图 (CDUCG)和核磁共振成像 (MRI)诊断主动脉夹层动脉瘤 (AD)的影像学特征 ,比较两种无创检查技术诊断AD的临床价值。方法 对临床疑诊AD的患者行CDUCG心脏各切面探查 ,重点扫查并测量主动脉各节段异常超声征象 (夹层发生部位、内膜片跨度、管径宽度等 ) ,对相同患者行MRI检查时在扫描图像上辨认并确定夹层发生的部位、撕裂范围等。结果 CDUCG诊断Ⅰ型AD 4例 ,Ⅱ型 2例 ,Ⅲ型AD 1例。MRI对Ⅰ、Ⅱ、Ⅲ型AD均可明确诊断。本文 3例Ⅲ型AD经MRI确诊并检出附壁血栓 2例 ,1例Ⅰ型AD可疑 ,余结果同CDUCG。结论 两种技术诊断AD各有优缺点 ,CDUCG偏重于诊断Ⅰ、Ⅱ型 ,MRI适合各型AD的诊断。前者更为迅速、直观 ,重复性强 ,可了解心血管病变的全部信息 ;危急重症患者不宜或难以接受MRI检查。 相似文献
5.
Bayrak S; Holmdahl R; Travers P; Lauster R; Hesse M; Dolling R; Mitchison NA 《International immunology》1997,9(11):1687-1699
Type II collagen (CII) is of immunological interest because of its
repetitive structure and properties as an autoantigen. The mouse gene has
recently been cloned, thus enabling T cell-defined epitopes to be
identified. Multiple novel epitopes on mouse CII are here detected in the
autoreactive T cell response. The major response is directed to an epitope
with residues 707-721 located on the CB10 fragment. Some 25 other epitopes
are also recognized, including the autologous homologue of the 256-270
epitope which dominates in the response to foreign collagen. The cells
reactive with mouse collagen peptides were of Th1 type, as judged by
release of IFN-gamma. No significant reactivity was detected to mouse CII
peptides during ongoing disease. Alignment of the mouse epitopes revealed a
sequence motif with characteristic side chains at residues P1, P4 and P7,
and to a lesser extent at P5, within a nonamer core sequence. Binding of
these epitopes was simulated in a computer model of the I-Aq molecule,
where peptides with anchor residues at P1, P4 and P7 were indeed found to
fit the binding groove best. The spacing of pockets and the fine structure
of the binding surface of the I-Aq molecule meshes with the repetitive
structure of the collagen (X-Y-Gly), thus providing a likely explanation
for the occurrence of multiple epitopes. Comparison with human DR binding
motifs showed that the I-Aq motif resembles most closely that of the DR4
subtypes which predispose for rheumatoid arthritis.
相似文献
6.
7.
8.
Multiple congenital supratentorial intracerebral cysts occurred in a newborn infant. The cysts, of varying size, content and lining, occupied the cerebral hemispheres. They formed a mosaic pattern on CT scan and left no trace of a recognisable ventricular system. Multiple surgical procedures were performed during the first year of life, and at one year the child was very well and asymptomatic, with two functioning shunts. 相似文献
9.
Eleven patients with portal hypertension due to infection with Schistosoma mansoni underwent splenectomy and devascularization operations. The patients were examined with ultrasound once preoperatively and twice postoperatively over a period of about 6 months. Following surgery there was significant and sequential reduction in the diameter of the portal vein at the hilum and the splenic vein at the pancreas. The liver lengths and index of liver size did not change significantly. No changes in the degree of periportal fibrosis could be detected. 相似文献
10.
α_1肾上腺素能受体阻滞剂萘哌地尔治疗慢性非细菌性前列腺炎的临床研究 总被引:13,自引:3,他引:10
目的:探讨α1肾上腺素能受体阻滞剂萘哌地尔(Naftopidil)治疗慢性非细菌性前列腺炎的有效性及安全性。方法:采用开放、自身对照、多中心的临床试验方法,应用萘哌地尔25mg,每日1次,对106例慢性非细菌性前列腺炎(NBP)患者进行了为期4周的治疗。以美国国立卫生院慢性前列腺炎症状评分(NIHCPSI)、前列腺液(EPS)WBC计数及最大尿流率(MFR)为疗效指标,对其有效性及安全性进行观察。结果:服药4周后,可评价病例105例。全组患者NIHCPSI总评分治疗前后平均减低12.0分(P<0.001),症状评分平均减低7.9分(P<0.001),生活质量评分平均减低4.1分(P<0.001)。EPS中WBC计数治疗前及治疗后分别为(15.2±15.1)、(9.5±12.0)个/HP(P<0.01)。MFR治疗前及治疗后分别为(19.2±4.8)、(22.7±4.9)ml/s(P<0.01)。按症状改善评价,治愈2例(1.9%),显效32例(30.5%),有效55例(52.4%),无效16例(15.2%)。总显效率为32.4%,总有效率为84.8%。3例有轻度头晕,1例食欲不佳,不良事件发生率3.81%。结论:萘哌地尔治疗慢性非细菌性前列腺炎安全、有效。 相似文献