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1.
D. R. Gustafsson L. Lei K. Luo X. Chu X. Zhao Q. Zhang F. Zou 《Medical and veterinary entomology》2019,33(3):407-419
In total, 366 birds representing 55 species in 24 families and eight orders, were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera) in two high‐altitude localities in Yunnan Province, China. In Ailaoshan, almost all of the birds examined were resident passeriforms, of which 36% were parasitized by chewing lice. In Jinshanyakou, most birds were on migration, and included both passerine and non‐passerine birds. Of the passerine birds caught in Jinshanyakou, only one bird (0.7%) was parasitized by chewing lice. The prevalence of Myrsidea and Brueelia‐complex lice on birds caught in Ailaoshan was higher than in previous reports. Of the chewing lice identifiable to species level, three represent new records for China: Actornithophilus hoplopteri (Mjöberg, 1910), Maculinirmus ljosalfar Gustafsson & Bush, 2017 and Quadraceps sinensis Timmermann, 1954. In total, 17 new host records are included, of which we describe two as new species in the Brueelia‐complex: Guimaraesiella (Cicchinella) ailaoshanensis sp. nov. ex Schoeniparus dubius dubius (Hume, 1874) and G. (C.) montisodalis sp. nov. ex Fulvetta manipurensis tonkinensis Delacour & Jabouille, 1930. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:9FC3D8EE‐2CED‐4DBE‐A1DB‐471B71260D27 . 相似文献
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Anna Nilsson Thomas E. Fehniger Lena Gustavsson Malin Andersson Kerstin Kenne Gy?rgy Marko-Varga Per E. Andrén 《PloS one》2010,5(7)
Readouts that define the physiological distributions of drugs in tissues are an unmet challenge and at best imprecise, but are needed in order to understand both the pharmacokinetic and pharmacodynamic properties associated with efficacy. Here we demonstrate that it is feasible to follow the in vivo transport of unlabeled drugs within specific organ and tissue compartments on a platform that applies MALDI imaging mass spectrometry to tissue sections characterized with high definition histology. We have tracked and quantified the distribution of an inhaled reference compound, tiotropium, within the lungs of dosed rats, using systematic point by point MS and MS/MS sampling at 200 µm intervals. By comparing drug ion distribution patterns in adjacent tissue sections, we observed that within 15 min following exposure, tiotropium parent MS ions (mass-to-charge; m/z 392.1) and fragmented daughter MS/MS ions (m/z 170.1 and 152.1) were dispersed in a concentration gradient (80 fmol-5 pmol) away from the central airways into the lung parenchyma and pleura. These drug levels agreed well with amounts detected in lung compartments by chemical extraction. Moreover, the simultaneous global definition of molecular ion signatures localized within 2-D tissue space provides accurate assignment of ion identities within histological landmarks, providing context to dynamic biological processes occurring at sites of drug presence. Our results highlight an important emerging technology allowing specific high resolution identification of unlabeled drugs at sites of in vivo uptake and retention. 相似文献
3.
Aint/Tacc3 is highly expressed in proliferating mouse tissues during development, spermatogenesis, and oogenesis. 总被引:1,自引:0,他引:1
Marjo Aitola Christine M Sadek Jan-Ake Gustafsson Markku Pelto-Huikko 《The journal of histochemistry and cytochemistry》2003,51(4):455-469
Aint was originally identified on the basis of its interaction in vitro with the aryl hydrocarbon nuclear receptor translocator (Arnt). Arnt is a common heterodimerization partner in the basic helix-loop-helix (bHLH)-PER-ARNT-SIM (PAS) protein family and is involved in diverse biological functions. These include xenobiotic metabolism, hypoxic response, and circadian rhythm. In addition, Arnt has a crucial role during development. Aint is a member of a growing family of transforming acidic coiled-coil (TACC) proteins and is the murine homologue of human TACC3. Here we report the spatiotemporal expression of Tacc3 mRNA and protein in embryonic, postnatally developing, and adult mouse tissues using in situ hybridization and immunocytochemistry. Tacc3 mRNA was highly expressed in proliferating cells of several organs during murine development. However, the only adult tissues expressing high levels were testis and ovary. Immunocytochemistry revealed that Tacc3 is a nuclear protein. Our results suggest that Tacc3 has an important role in murine development, spermatogenesis, and oogenesis. 相似文献
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L. Marklund M. Johansson U. Gustafsson L. Andersson A. K. Winterö M. Fredholm P. D. Thomsen 《Animal genetics》1993,24(5):333-338
Restriction fragment length polymorphisms (RFLPs) were described for the porcine loci for β-glucosidase (GBA) and the β-polypeptide 1 of the Na+, K+-transporting ATPase (ATP1B1). Linkage analyses using a three-generation pedigree provided evidence for the assignment of ATP1B1, GBA and two microsatellite loci (S0001 and S0067) to a previously described linkage group comprising the loci for blood group L (EAL) and an anonymous microsatellite (S0097). The linear order of the six markers was determined with confidence by multipoint analyses and the length of the linkage group was estimated at 88 CM. This linkage group was assigned to pig chromosome 4 on the basis of a previous physical localization of the ATP1B1 gene. In situ hybridization data for S0001 presented in this study were consistent with a localization on chromosome 4 and suggested a regional localization to 4pl2-pl3. The present study reveals conflicting data concerning the genetic localization of the K88 loci controlling the expression of the receptors for the E. coli pilus antigens. One group has reported data suggesting a loose linkage between K88 and EAL, now mapped to chromosome 4, whereas two other groups have found linkage between K88 and the transferrin locus (TF), mapped to chromosome 13 by in situ hybridization. 相似文献
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Summary Phenylalanine production from E. coli KA 197/pJN6 (plasmid harboring genes for aro F, phe AFBR, AmpR and TcR) was studied under varying nutritional conditions in batch and continuous cultures. In batch culture experiments where growth was deliberately interrupted by limiting concentrations of sulphate and phosphate the phenylalanine production continued from the non-growing cells. However, the depletion of phosphate resulted in an immediate cessation of phenylalanine production but thereafter a low specific rate of phenylalanine formation resumed, while the decrease in specific rate of product formation was less after sulphate depletion. In the chemostat experiments, however, phosphate limitation was the only case where the specific rate of phenylalanine formation remained constant, while at the corresponding time in sulphate and glucose limited chemostats it was declining respectively had ceased. 相似文献
10.
The Susceptibility of Photosynthesis to Photoinhibition and the Capacity of Recovery in High and Low Light Grown Cyanobacteria, Anacystis nidulans 总被引:11,自引:3,他引:8 下载免费PDF全文
The susceptibility of photosynthesis to photoinhibition and the rate of its recovery were studied in the cyanobacterium Anacystis nidulans grown at a low (10 micromoles per square meter per second) and a high (120 micromoles per square meter per second) photosynthetically active radiation. The rate of light limited photosynthetic O2 evolution was measured to determine levels of photoinhibition and rates of recovery. Studies of photoinhibition and recovery with and without the translation inhibitor streptomycin demonstrated the importance of a recovery process for the susceptibility of photosynthesis to photoinhibition. We concluded that the approximately 3 times lower susceptibility to photoinhibition of high light than of low light grown cells, significantly depended on high light grown cells having an approximately 3 times higher recovery capacity than low light grown cells. It is suggested that these differences in susceptibility to photoinhibition and recovery depends on high light grown cells having a higher turnover rate of photosystem II protein(s) that is(are) the primary site(s) of photodamage, than have low light grown cells. Furthermore, we demonstrated that photoinhibition of A. nidulans may occur under physiological light conditions without visible harm to the growth of the cell culture. The results give support for the hypotheses that the net photoinhibitory damage of photosystem II results from the balance between the photoinhibitory process and the operation of a recovery process; the capacity of the latter determining significant differences in the susceptibility of photosynthesis to photoinhibition of high and low light grown A. nidulans. 相似文献