全文获取类型
收费全文 | 539篇 |
免费 | 32篇 |
国内免费 | 7篇 |
学科分类
医药卫生 | 578篇 |
出版年
2021年 | 15篇 |
2020年 | 4篇 |
2019年 | 1篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2016年 | 12篇 |
2015年 | 10篇 |
2014年 | 12篇 |
2013年 | 27篇 |
2012年 | 22篇 |
2011年 | 10篇 |
2010年 | 25篇 |
2009年 | 26篇 |
2008年 | 12篇 |
2007年 | 10篇 |
2006年 | 19篇 |
2005年 | 11篇 |
2004年 | 8篇 |
2003年 | 13篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 19篇 |
1998年 | 35篇 |
1997年 | 25篇 |
1996年 | 21篇 |
1995年 | 13篇 |
1994年 | 22篇 |
1993年 | 23篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 5篇 |
1989年 | 13篇 |
1988年 | 15篇 |
1987年 | 9篇 |
1986年 | 14篇 |
1985年 | 7篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 12篇 |
1980年 | 12篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 9篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有578条查询结果,搜索用时 8 毫秒
41.
Oral Diseases (2010) 16 , 160–166 Objective: The aim of this comparative study was to analyze cytopathologically and chemico‐physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. Materials and methods: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back‐scattered) scanning electron microscope (SEM) and X‐ray microanalysis to study piercing fragments. Results: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X‐ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. Conclusions: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted. 相似文献
42.
43.
Lineage-restricted regulation of the murine SCL/TAL-1 promoter 总被引:10,自引:2,他引:10
Bockamp EO; McLaughlin F; Murrell AM; Gottgens B; Robb L; Begley CG; Green AR 《Blood》1995,86(4):1502-1514
44.
红豆杉提取物中紫杉醇的反相高效液相色谱法测定 总被引:2,自引:0,他引:2
本文报道应用反相高效液相色谱法测定红豆杉提取物中紫杉醇的含量,以倍他米松作内标,在填充以10μm LiChrosorb RP-18固定相的250×4mm不锈钢柱上以甲醇-水(30:10v/v)作流动相。228 nm处检测。本法简便、快速、准确,适用于微量样品的测定。 相似文献
45.
薄层扫描法测定熊胆引流物中胆汁酸含量 总被引:4,自引:0,他引:4
熊胆向以贵重药材闻名,被称之为稀有药品,为开发熊胆资源,解决熊胆奇缺问题,我校解剖教研室已成功地完成了人工引流熊胆汁技术,可随时进行人工引流获取熊胆汁。为了确定胆汁的质量指标,了解其主要成分,我们进行了引流胆汁与天然熊胆的分析。文献报道,熊胆中主要含熊去氧胆酸(ursodesoxycholic acid,UDCA)、鹅去氧胆酸(cheno desoxycholic acid,CDCA)、胆酸(cholic acid,CA)、去氧胆酸(deoxycholic,acid DCA)等。 相似文献
46.
47.
Complementary medicine: use and attitudes among GPs 总被引:9,自引:0,他引:9
BACKGROUND: Information about use and attitudes of GPs towards
complementary medicine is required in order to inform the debate about its
place within mainstream medicine. There is evidence that public use of
complementary medicine is particularly high in the South-West of England.
OBJECTIVE: This study aimed to determine the use of, and attitudes towards,
complementary medicine among GPs. METHODS: A questionnaire survey was
performed of all primary care physicians working in the health service in
Devon and Cornwall. RESULTS: Replies were received from 461 GPs, a response
rate of 47%. A total of 314 GPs (68%, range 32-85%) had been involved in
complementary medicine in some way during the previous week. One or other
form of complementary medicine was practised by 74 of the respondents
(16%), the two most common being homoeopathy (5.9%) and acupuncture (4.3%).
In addition, 115 of the respondents (25%) had referred at least one patient
to a complementary therapist in the previous week, and 253 (55%) had
endorsed or recommended treatment with complementary medicine.
Chiropractic, acupuncture and osteopathy were rated as the three most
effective therapies, and the majority of respondents believed that these
three therapies should be funded by the health service. A total of 176
(38%) of respondents reported adverse effects, most commonly after
manipulation. CONCLUSION: Over two-thirds of the GPs in Devon and Cornwall
who responded to the survey had been involved with complementary medicine
in some way during the previous week. This figure is higher than the
national average. The majority of respondents believed that acupuncture,
chiropractic and osteopathy were effective and should be funded by the NHS.
相似文献
48.
49.
Expression of phosphorylcholine-specific B cells during murine development 总被引:1,自引:0,他引:1 下载免费PDF全文
NH Sigal AR Pickard ES Metcalf PJ Gearhart NR Klinman 《The Journal of experimental medicine》1977,146(4):933-948
The TEPC 15 (T15) clonotype, a putatively germline antibody specificity, does not appear in the neonatal B-cell repertoire until approximately 1 wk of age. This report extends this observation by the demonstration that (a) the T15 clonotype follows similar kinetics of appearance in germfree as well as conventionally-reared mice; (b) maternal influences and genetic background play a minor role in the development of the T15 clonotype since CBFI neonates raised by C57BL/6 or BALB/c mothers acquire the T15 clonotype at the same time in ontogeny as BALB/c neonates; (c) the lack of phosphorylcholine (PC)-specific B cells shortly after birth is reflected in a dearth of PC-binding cells in the neonate as well; and (d) no PC-specifc B cells are found in 19-day fetal liver or in bone marrow until 7 days of life, coincident with their appearance in the spleen. These findings, along with a previous report that PC-specific splenic B cells are tolerizable as late as day 10 after birth, confirm the invariant, late occurrence of the T15 clonotype and support a highly- ordered, rigorously predetermined mechanism for the acquisition of the B- cell repertoire. The results are discussed in light of other studies on the ontogeny of B-cell specificity, and in terms of the implications on the mechanism by which antibody diversity is generated. 相似文献
50.
We investigated the ability of blood B cells, bone marrow (BM) plasma cells, and terminal leukemic plasma cells (T-PCL) from patients with multiple myeloma (MM) to migrate on extracellular matrix proteins. Hyaluronan (HA), but not collagen type I, collagen type IV, or laminin, promoted migration of MM blood B cells, as determined by time-lapse video microscopy. Between 13% and 20% of MM blood B cells migrated on HA with an average velocity of 19 micron/min, and greater than 75% of MM blood B cells exhibited vigorous cell movement and plasma membrane deformation, as did circulating T-PCL and extraskeletal plasma cells from patients with MM. In contrast, plasma cells obtained from BM of patients with MM lacked motility on all substrates tested and did not exhibit cell membrane protrusions or cellular deformation. MM blood B cells and MM plasma cells from all sources examined expressed the HA- binding receptors receptor for HA-mediated motility (RHAMM) and CD44. On circulating MM B cells, both RHAMM and CD44 participated in HA- binding, indicating their expression ex vivo in an activated conformation. In contrast, for the majority of BM plasma cells in the majority of patients with MM, expression of RHAMM or CD44 was not accompanied by HA binding. A minority of patients did have HA-binding BM plasma cells, involving both RHAMM and CD44, as evidenced by partial blocking with monoclonal antibodies (MoAbs) to RHAMM or to CD44. Despite HA binding by both RHAMM and CD44, migration of MM blood B cells on HA was inhibited by anti-RHAMM but not by anti-CD44 MoAbs, indicating that RHAMM but not CD44 mediates motility on HA. Thus, circulating B and plasma cells in MM exhibit RHAMM- and HA-dependent motile behavior indicative of migratory potential, while BM plasma cells are sessile. We speculate that a subset(s) of circulating B or plasma cells mediates malignant spread in myeloma. 相似文献