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101.
During 1983, 887 fine wool rams were subjected to breeding soundness evaluation to determine effects of age and scrotal circumference on semen characteristics. Of rams evaluated, 94.4, 84.8, and 81.9% of young (6 yr), respectively, were rated as satis-factory. Old rams had fewer (P < 0.05) motile cells and more (P < 0.05) abnormal cells than young rams. Among older rams there was a higher percentage (P < 0.05) with testicular lesions than among young or mature rams. Scrotal circumference was positively correlated (P < 0.01) with semen volume and percentage of motile normal cells. Motility was negatively correlated (P < 0.01) with percentage of abnormal cells. Mature and old rams with large (>/=36.7 cm) testis had more (P < 0.10) abnormal cells than those in the same age groups with smaller testis. Scrotal circumference was positively correlated (P < 0.10) to volume and motility in mature and old rams, while motility was negatively correlated (P < 0.01) to percentage of abnormal cells in all age groups. Previous semen testing reduced (P < 0.05) the percentage of mature rams with leucocytes. Vaccination against epididymitis reduced (P < 0.05) the incidence of mature rams with leucocytes and testicular lesions. Brucella ovis was recovered from 54 (67.5%) of 80 ejaculates cultured. Among rams infected with B . ovis , only three (5.6%) were vaccinated against B . ovis and had their semen tested previously.  相似文献   
102.
Podocytes are insulin-sensitive and take up glucose in response to insulin. This requires nephrin, which interacts with vesicle-associated membrane protein 2 (VAMP2) on GLUT4 storage vesicles (GSVs) and facilitates their fusion with the plasma membrane. In this paper, we show that the filament-forming GTPase septin 7 is expressed in podocytes and associates with CD2-associated protein (CD2AP) and nephrin, both essential for glomerular ultrafiltration. In addition, septin 7 coimmunoprecipitates with VAMP2. Subcellular fractionation of cultured podocytes revealed that septin 7 is found in both cytoplasmic and membrane fractions, and immunofluorescence microscopy showed that septin 7 is expressed in a filamentous pattern and is also found on vesicles and the plasma membrane. The filamentous localization of septin 7 depends on CD2AP and intact actin organization. A 2-deoxy-d-glucose uptake assay indicates that depletion of septin 7 by small interfering RNA or alteration of septin assembly by forchlorfenuron facilitates glucose uptake into cells and further, knockdown of septin 7 increased the interaction of VAMP2 with nephrin and syntaxin 4. The data indicate that septin 7 hinders GSV trafficking and further, the interaction of septin 7 with nephrin in glomeruli suggests that septin 7 may participate in the regulation of glucose transport in podocytes.  相似文献   
103.
We suggest that interactions with strangers at work influence the likelihood of depressive disorders, as they serve as an environmental stressor, which are a necessary condition for the onset of depression according to diathesis-stress models of depression. We examined a large dataset (N = 76,563 in K = 196 occupations) from the German pension insurance program and the Occupational Information Network dataset on occupational characteristics. We used a multilevel framework with individuals and occupations as levels of analysis. We found that occupational environments influence employees’ risks of depression. In line with the quotation that ‘hell is other people’ frequent conflictual contacts were related to greater likelihoods of depression in both males and females (OR = 1.14, p<.05). However, interactions with the public were related to greater likelihoods of depression for males but lower likelihoods of depression for females (ORintercation = 1.21, p<.01). We theorize that some occupations may involve interpersonal experiences with negative emotional tones that make functional coping difficult and increase the risk of depression. In other occupations, these experiences have neutral tones and allow for functional coping strategies. Functional strategies are more often found in women than in men.  相似文献   
104.
Summary 1242 HLA-ABC haplotypes of the North German population (Hamburg) as deduced by family analyses are described. They are in perfect agreement with recently published data by Mayr (1977) from Austria (Vienna) in all parameters tested: frequency of the single HLA-alleles, haplotype distribution and linkage disequilibrium values. Gametic association studies revealed that 69.4% of the B and C genes (map distance 0.2 cM) 36.9% of the A and C genes (0.6 cM), but only 23.2% of the A and B genes (0.8 cM) were significantly more often combined than expected due to their frequencies. From these findings it seems likely that the linkage disequilibrium within the MHC is rather due to a short evolutionary period than to selective forces. Some observations as to the most common European haplotype A1,B8 are discussed.  相似文献   
105.
Summary White and red mutants of Phycomyces, derived from two independent wild types (yellow) by mutagenesis using nitrosoguanidine, either in a single step (26 white, 5 red mutants), or in two steps (10 white mutants, from one of the red mutants) were studied with respect to complementation in heterokaryons. The tests clearly establish the involvement of three and only three genes, here named carA, carB, and carB. The carA and the carR mutants are white, the carA mutants do not accumulate phytoene, the carB mutants do. The carR mutants are red and accumulate lycopene. The two step mutants are either carA and carR, or carB and carR double mutants. A few of the white mutants obtained in a single mutagenization step are affected in carA and carR. They may be polar mutants in an operon or accidental double mutants.  相似文献   
106.
Symmetrical lupoid onychodystrophy (SLO) is an immune-mediated disease in dogs affecting the claws with a suggested autoimmune aethiology. Sequence-based genotyping of the polymorphic exon 2 from DLA-DRB1, -DQA1, and -DQB1 class II loci were performed in a total of 98 SLO Gordon setter cases and 98 healthy controls. A risk haplotype (DRB1*01801/DQA1*00101/DQB1*00802) was present in 53% of cases and 34% of controls and conferred an elevated risk of developing SLO with an odds ratio (OR) of 2.1. When dogs homozygous for the risk haplotype were compared to all dogs not carrying the haplotype the OR was 5.4. However, a stronger protective haplotype (DRB1*02001/DQA1*00401/DQB1*01303, OR = 0.03, 1/OR = 33) was present in 16.8% of controls, but only in a single case (0.5%). The effect of the protective haplotype was clearly stronger than the risk haplotype, since 11.2% of the controls were heterozygous for the risk and protective haplotypes, whereas this combination was absent from cases. When the dogs with the protective haplotype were excluded, an OR of 2.5 was obtained when dogs homozygous for the risk haplotype were compared to those heterozygous for the risk haplotype, suggesting a co-dominant effect of the risk haplotype. In smaller sample sizes of the bearded collie and giant schnauzer breeds we found the same or similar haplotypes, sharing the same DQA1 allele, over-represented among the cases suggesting that the risk is associated primarily with DLA-DQ. We obtained conclusive results that DLA class II is significantly associated with risk of developing SLO in Gordon setters, thus supporting that SLO is an immune-mediated disease. Further studies of SLO in dogs may provide important insight into immune privilege of the nail apparatus and also knowledge about a number of inflammatory disorders of the nail apparatus like lichen planus, psoriasis, alopecia areata and onycholysis.  相似文献   
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109.
The pattern recognition receptor CD36 initiates a signaling cascade that promotes microglial activation and recruitment to beta-amyloid deposits in the brain. In the present study we identify the focal adhesion-associated proteins p130Cas, Pyk2, and paxillin as novel members of the tyrosine kinase signaling pathway downstream of CD36 and show that assembly of this complex is essential for microglial migration. In primary microglia and macrophages exposed to beta-amyloid, the scaffolding protein p130Cas is rapidly tyrosine-phosphorylated and co-localizes with CD36 to membrane ruffles contemporaneous with F-actin polymerization. These beta-amyloid-stimulated events are not detected in CD36 null cells and are dependent on CD36 activation of Src family tyrosine kinases. Fyn, a Src kinase known to interact with CD36, co-precipitates with p130Cas and is an essential upstream intermediate in the signaling pathways leading to phosphorylation of the p130Cas substrate domain. Furthermore, the p130Cas-interacting kinase Pyk2 and the cytoskeletal adapter protein paxillin also demonstrate CD36-dependent phosphorylation, identifying these focal adhesion molecules as additional members of this beta-amyloid signaling cascade. Disruption of this p130Cas complex by small interfering RNA silencing inhibits p44/42 mitogen-activated protein kinase phosphorylation and microglial migration, illustrating the importance of this pathway in microglial activation and recruitment. Together, these data are the first to identify the signaling cascade that directly links CD36 to the actin cytoskeleton and, thus, implicates it in diverse processes such as cellular migration, adhesion, and phagocytosis.  相似文献   
110.
Two monoclonal antibodies have been characterized as being against avian type VI collagen. By competition ELISA, the antibodies bound to the native type VI collagen molecule but not to its separated chains or to any of the other native collagen types tested. By rotary shadowing analysis of complexes of antibody-type VI collagen monomers, one of the antibodies (VI-EC6) has been shown to bind to a site in the triple helical domain of the molecule. The site at which this antibody binds to the dimeric form of type VI collagen is consistent with the previously proposed model for a supramolecular organization of the molecule (Furthmayr et al., Biochem j 211 (1983) 303) in which the monomers are arranged in an antiparallel, slightly staggered overlap. Immunofluorescence analyses of sections of chicken eyes and skeletal muscle demonstrate that type VI collagen is a major component of most stromal matrices.  相似文献   
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