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排序方式: 共有445条查询结果,搜索用时 171 毫秒
1.
Ross A. Robinson Samuel C. Griffiths Lieke L. van de Haar Tomas Malinauskas Eljo Y. van Battum Pavol Zelina Rebekka A. Schwab Dimple Karia Lina Malinauskaite Sara Brignani Marleen H. van den Munkhof Özge Düdükcü Anna A. De Ruiter Dianne M.A. Van den Heuvel Benjamin Bishop Jonathan Elegheert A. Radu Aricescu R. Jeroen Pasterkamp Christian Siebold 《Cell》2021,184(8):2103-2120.e31
2.
Immunoprecipitation of NP-40 lysates of 125I-labeled lymph-node cells with different anti-H-2 sera and with anti-Qa-2 serum has shown that the BALB/cByA strain (H-2d, Qa-2-negative) expresses, besides H-2Ld, another molecule that is not detectable in the BALB/c-H-2dm2 strain. Electrophoresis in SDS polyacrylamide gels indicated that this molecule, provisionally designated Lq, has an apparent molecular weight of 41000 daltons, in contrast to approximately 49000 daltons for H-2Kd and H-2Ld, and 47000 daltons for H-2Dd molecules. The anti-Qa-2 serum precipitated from the Qa-2-positive strains BALB/cHeA but not from the Qa-2-negative strains BALB/cByA and BALB/c-H-2dm2 a protein that gave a very strong band corresponding to the molecular weight 41000 daltons in the gel electrophoresis. The biochemical characteristics of the Lq molecule are thus more similar to those of Qa-2 than of H-2 antigens. 相似文献
3.
H. J. P. M. Koenen Marjon J. Smit Marleen M. J. A. Simmelink Bart Schuurman Robert H. J. Beelen Sybren Meijer 《Cancer immunology, immunotherapy : CII》1996,42(5):310-316
Milky spots in the greater omentum are small accumulations of leucocytes that consist mainly of macrophages and have recently
shown to be a selective dissemination site of intraperitoneal (i. p.) inoculated tumour cells. However, milky-spot macrophages
show tumoricidal activity and may, therefore, be an excellent source of effector cells suited for local immunotherapy. In
the present study we first examined whether granulocyte/macrophage- colony-stimulating factor (GM-CSF) treatment of isolated
milky-spot macrophages affects the cytotoxicity against syngeneic colon carcinoma cells (CC531) in vitro. Secondly, we studied
the influence of intraperitoneal GM-CSF administration on the number and antitumour activity of milky-spot and peritoneal
macrophages. All studies were performed in Wag/Rij rats in which a syngeneic colon carcinoma cell line (CC531) is available.
The results of the in vitro study showed that GM-CSF treatment of the omental macrophages led to an increased cytotoxicity
against the tumour cell line. Intraperitoneal administration of 1000 U GM-CSF daily for 7 consecutive days demonstrated both
an enhanced antitumour activity of the milky-spot macrophages and an increase in the milky-spot macrophage population. An
increase in the proliferative capacity, according to bromodeoxyuridine incorporation, was shown in the milky-spot macrophages.
Taking into account both the enhanced macrophage number and their enhanced activity upon i. p. GM-CSF treatment, the milky-spot
macrophages may provide a rationale for local intraperitoneal immunotherapy in the prevention of intra-abdominal tumour growth.
Received: 11 April 1996 / Accepted: 21 May 1996 相似文献
4.
Osvaldo Loquiha Niel Hens Leonardo Chavane Marleen Temmerman Marc Aerts 《Biometrical journal. Biometrische Zeitschrift》2013,55(5):647-660
Count data are very common in health services research, and very commonly the basic Poisson regression model has to be extended in several ways to accommodate several sources of heterogeneity: (i) an excess number of zeros relative to a Poisson distribution, (ii) hierarchical structures, and correlated data, (iii) remaining “unexplained” sources of overdispersion. In this paper, we propose hierarchical zero‐inflated and overdispersed models with independent, correlated, and shared random effects for both components of the mixture model. We show that all different extensions of the Poisson model can be based on the concept of mixture models, and that they can be combined to account for all different sources of heterogeneity. Expressions for the first two moments are derived and discussed. The models are applied to data on maternal deaths and related risk factors within health facilities in Mozambique. The final model shows that the maternal mortality rate mainly depends on the geographical location of the health facility, the percentage of women admitted with HIV and the percentage of referrals from the health facility. 相似文献
5.
A new genus of the harpacticoid family Laophontidae is described and named Peltidiphonte gen. n. Eight new species are assigned to this genus; they were collected from different locations in the Indo-West Pacific
Ocean, including the Comoros, the Kenyan coast, the Red Sea, the Andaman Islands, the northern coast of Papua New Guinea,
the Solomon Islands and the northeastern coast of Australia. Most of the specimens were collected from dead coral substrates,
suggesting a close affinity between the members of the new genus and this substrate. Peltidiphonte gen. n. can easily be discriminated from other genera of the family by the extremely depressed body and by the shape of the
antennule, bearing two (or three) processes on the first segment and a hook-like process along the outer margin of the second
segment. An identification key for the new genus is provided. 相似文献
6.
Pollen spectra of 23 Cundill pollen traps from 23 different sampling sites in Southwest Turkey are compared with the corresponding pollen spectra of moss cushions from the same sites. The Cundill pollen traps represent the modern pollen rain data from one year whereas the moss cushions represent the pollen rain of several years. The comparative study reveals some main differences between the two pollen entrapment media. The one-year entrapment medium (pollen trap) appears to be more sensitive for local (releve area 10x10 m) and regional (100-500 m, or a few kilometres for Olea europaea) vegetation. Pollen spectra of moss cushions are dominated by high pine pollen percentage values and hardly sense fine vegetation structures. The conclusion of this comparative modern pollen study allows to interpret fossil sediment spectra from the Near East in a more critical way. It is concluded that one should preferably sample rapidly deposited sediments for palynological analyses, as the resulting highresolution pollen diagrams will be most informative about the former vegetation patterns. 相似文献
7.
Ping Wang Paul P.C.A. Menheere Arne Astrup Malene R. Andersen Marleen A. van Baak Thomas M. Larsen Susan Jebb Anthony Kafatos Andreas F.H. Pfeiffer J. Alfredo Martinez Teodora Handjieva‐Darlenska Petr Hlavaty Nathalie Viguerie Dominique Langin Wim H.M. Saris Edwin C.M. Mariman Diogenes consortium 《Obesity (Silver Spring, Md.)》2013,21(10):1997-2006
8.
Christopher I. Cazzonelli Marleen Vanstraelen Sibu Simon Kuide Yin Ashley Carron-Arthur Nazia Nisar Gauri Tarle Abby J. Cuttriss Iain R. Searle Eva Benkova Ulrike Mathesius Josette Masle Ji?í Friml Barry J. Pogson 《PloS one》2013,8(7)
Plant-specific PIN-formed (PIN) efflux transporters for the plant hormone auxin are required for tissue-specific directional auxin transport and cellular auxin homeostasis. The Arabidopsis PIN protein family has been shown to play important roles in developmental processes such as embryogenesis, organogenesis, vascular tissue differentiation, root meristem patterning and tropic growth. Here we analyzed roles of the less characterised Arabidopsis PIN6 auxin transporter. PIN6 is auxin-inducible and is expressed during multiple auxin–regulated developmental processes. Loss of pin6 function interfered with primary root growth and lateral root development. Misexpression of PIN6 affected auxin transport and interfered with auxin homeostasis in other growth processes such as shoot apical dominance, lateral root primordia development, adventitious root formation, root hair outgrowth and root waving. These changes in auxin-regulated growth correlated with a reduction in total auxin transport as well as with an altered activity of DR5-GUS auxin response reporter. Overall, the data indicate that PIN6 regulates auxin homeostasis during plant development. 相似文献
9.
Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha−1 in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha−1 to an increase of 8 Mg C ha−1. In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes. 相似文献
10.
Marleen Perseke Anja Golombek Martin Schlegel Torsten H. Struck 《Molecular phylogenetics and evolution》2013,66(3):898-905
Deuterostomia, one of the three major lineages of Bilateria, comprises many well-known animals such as vertebrates, sea squirts, sea stars and sea urchins. Whereas monophyly of Deuterostomia and several subtaxa is well supported, the relationships of these to each other and, hence, deuterostome relationships are still uncertain. To address these issues in deuterostome phylogeny we analyzed datasets comprising more than 300 complete deuterostome mitochondrial genomes. Based on sequence information, the results revealed support for several relationships such as a basal position of Xenoturbella within Deuterostomia or for taxa like Craniota or Ambulacraria, but yielded also problems in some taxa, e.g. Tunicata, Pterobranchia and Ophiuroidea, due to long-branch artifacts. However, within tunicates the relationships are well supported. Variation in the genetic code was also informative and, e.g., supported the taxon Ambulacraria including Pterobranchia. 相似文献