全文获取类型
收费全文 | 146篇 |
免费 | 11篇 |
出版年
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 6篇 |
2016年 | 4篇 |
2015年 | 6篇 |
2014年 | 7篇 |
2013年 | 7篇 |
2012年 | 7篇 |
2011年 | 3篇 |
2010年 | 8篇 |
2009年 | 6篇 |
2008年 | 4篇 |
2007年 | 4篇 |
2006年 | 11篇 |
2005年 | 8篇 |
2004年 | 3篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2001年 | 3篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 3篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1973年 | 3篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1969年 | 2篇 |
1967年 | 2篇 |
1966年 | 4篇 |
1953年 | 2篇 |
1952年 | 1篇 |
排序方式: 共有157条查询结果,搜索用时 0 毫秒
151.
A marked increase in reticular argyrophilia may be obtained in the Foot ammoniated silver carbonate technic by interposing a strong periodic acid oxidation, 4% aqueous for 2 hours at 25-27°C., prior to silvering. Sections so oxidized before the silver bath show a histological picture of connective tissue that is stronger than that given by the original technic. Stroma of lymphoid tissues (but not other types) is further intensified by brief (5-10 sec.) passage through aqueous 1.5% uranium nitrate after oxidation but before silver impregnation. The specific action of periodic acid (cleavage of the 1,2-glycol linkage to produce aldehyde radicals) strengthens the premise that the carbonyl radical plays an important part in the phenomenon of connective tissue argyrophilia. 相似文献
152.
Pentti Kuusela Tapio Vartio Matti Vuento Erling B. Myhre Ilkka Hemmilä 《FEMS microbiology letters》1986,36(1):57-62
Abstract The application of time-resolved fluorimetry was evaluated in the study of staphylococcal and streptococcal attachment to fibronectin-coated coverslips. The test system allowed the use of low bacterial concentrations (2 × 105 −107 bacteria per ml), in contrast to the much higher concentrations of bacteria used in earlier assays. The bacteria attached much better to fibronectin-coated plastic surfaces than to albumin-coated ones, but there were differences between the individual strains. Soluble fibronectin inhibited the adsorption of staphylococci but enhanced streptococcal attachment to fibronectin-coated surfaces. Purified antibodies to fibronectin inhibited both staphylococcal and streptococcal adhesion in a dose-dependent way. Our results show that time-resolved fluorimetry is a very sensitive method for quantitating bacterial attachment. 相似文献
153.
154.
Kurt I. Draget Sigrid Myhre Kjell Evjen Kjetill
stgaard 《Biotechnic & histochemistry》1988,63(3):159-164
A simple method for electron microscopic preparation of plant protoplasts is described. The main problems in preparing these fragile protoplasts for electron microscopy have been cell collapse due to steep gradients between protoplasts and fixatives and unacceptable loss of material during the many steps of the procedure. These problems may be solved by immobilization of the protoplasts in calcium alginate beads. The free diffusion properties of this gel prevent steep gradients. The beads also simplify handling and prevent loss of material. Protoplasts isolated from hypocotyls of rape, Brassica napus (var. Niklas), have been used as a model system. Transmission electron microscopy of the immobilized protoplasts osmotically stabilized with glucose demonstrated adequate structural and ultrastructural preservation. 相似文献
155.
The fourth component of rat complement was purified to homogeneity by sequential chromatography of rat plasma in benzamidine on QAE-A50, SP-C50, hydroxyapatite, and gel filtration on Bio-Gel A 1.5. The final material was homogeneous on SDS-PAGE analysis and had a calculated m.w. of 198,000. A monospecific antibody against rat C4 was obtained from immunized rabbits. The concentration of rat C4 in the plasma of normal 4-month-old Wistar rats was 190 +/- 34 microgram/ml (mean +/- 1 S.D.). 相似文献
156.
Mitochondrial DNA analysis of Rhipicephalus sanguineus s.l. from the western Iberian peninsula
下载免费PDF全文
![点击此处可从《Medical and veterinary entomology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
C. ALMEIDA R. SIMÕES M. J. COIMBRA‐DORES F. ROSA D. DIAS 《Medical and veterinary entomology》2017,31(2):167-177
Rhipicephalus sanguineus Latreille (1806) (Ixodida: Ixodidae) is considered to be the most widely distributed tick and to have a vast range of habitats and hosts, including livestock, pets and wildlife. In addition to morphological differences, recent investigations using approaches based on molecular genetic markers have revealed the existence of different R. sanguineus lineages in different geographic regions. In this study, 475 ticks collected from dogs in the western Iberian peninsula were studied both morphologically and genetically, using 12S and 16S rDNA and COI gene markers in order to clarify the controversy over the systematic status of R. sanguineus sensu lato in Western Europe, and to compare the present data with those sourced from studies conducted in other regions of the world. Despite the high morphometric variability, particularly on spiracles in both genders and in female genitalia, data obtained with different genetic molecular markers show very low variability, suggesting the existence of a unique species. In addition, the phylogenetic analysis showed genetic uniformity, supporting the existence of a well‐defined clade consisting of R. sanguineus s.l. specimens from Western Europe that are distinct from R. sanguineus s.l. from Africa. Furthermore, these data corroborate the existence of a polymorphic species in Western Europe, which requires to be consensually redescribed in view of its medical and veterinary importance in pathogen transmission. 相似文献
157.
Work capacity in acute exposures to altitude 总被引:1,自引:0,他引:1