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171.
A 19-gauge needle biopsy was taken of the testis of mink in late January. When scores from 1 to 10 were given according to the developmental stage and number of spermatogenic cells, males scoring 8-10 returned significantly better breeding results than did males having scores less than 7. The biopsy did not affect libido or induce other disturbances of fertility. Fine-needle aspiration biopsy of the testis is possibly the most convenient and accurate infertility assay in mink breeding. 相似文献
172.
Scoring the agar plate before incubation under unidirectional light led to a rapid separation of gliding filamentous cyanobacteria from their contaminating bacteria. Twenty strains were purified by the method. Additionally, 13 axenic cyanobacterial strains were isolated from pour plates made after treatment of cyanobacterial cultures in tryptone-yeast extract-glucose broth with cycloserine in darkness to select for obligate photoautotrophs. 相似文献
173.
CNV-seq, a new method to detect copy number variation using high-throughput sequencing 总被引:2,自引:0,他引:2
Background
DNA copy number variation (CNV) has been recognized as an important source of genetic variation. Array comparative genomic hybridization (aCGH) is commonly used for CNV detection, but the microarray platform has a number of inherent limitations. 相似文献174.
We have previously discovered and characterized a novel essential enterobacterial protein, the Ssc protein of Salmonella typhimurium and found that the mutation Val291----Met in this protein inhibits bacterial growth at 42 degrees C and the function of its outer membrane permeability barrier at 37 degrees C [7]. In the present paper we prepared, by site-directed mutagenesis, a series of novel plasmid-encoded Ssc mutant proteins and tested their ability to compensate the loss of wild-type Ssc. The mutant proteins Met288----Lys and Gly289----Asp completely lacked this ability, and accordingly, were very defective. Ssc mutants Met288----Leu, Met290----Lys, and Met292----Lys were partially defective. Mutants Met290----Leu and Met292----Leu were non-defective as were also four randomly made mutant proteins with mutations outside the 288-292 region. The S. typhimurium derivative which contained both the chromosomally encoded Ssc Val291----Met and the plasmid-encoded Ssc Gly289----Asp had an outer membrane defect more severe than that caused by SscMet291 only. The mutant Ssc proteins had very little, if any, effect on the outer membrane function in the presence of wild-type Ssc. Even though the function of Ssc is not yet known, our results indicate that region 288-292 is important and that SscAsp289 is thus far the most defective mutant Ssc. 相似文献
175.
Milićević NM Miljković MD Milićević Z Labudović-Borović M Wang X Laan M Peterson P Randall TD Westermann J 《Histochemistry and cell biology》2011,135(6):593-601
We have already shown that metallophilic macrophages, which represent an important component in the thymus physiology, are
lacking in lymphotoxin-β receptor-deficient mice. However, further molecular requirements for the development and correct
tissue positioning of these cells are unknown. To this end, we studied a panel of mice deficient in different chemokine ligand
or receptor genes. In contrast to normal mice, which have these cells localized in the thymic cortico-medullary zone (CMZ)
as a distinct row positioned between the cortex and medulla, in plt/plt (paucity of lymph node T cells) mice lacking the functional
CCL19/CCL21 chemokines, metallophilic macrophages are not present in the thymic tissue. Interestingly, in contrast to the
CCL19/21-deficient thymus, metallophilic macrophages are present in the CCR7-deficient thymus. However, these cells are not
appropriately located in the CMZ, but are mostly crowded in central parts of thymic medulla. The double staining revealed
that these metallophilic macrophages are CCR7-negative and CXCR3-positive. In the CXCL13-deficient thymus the number, morphology
and localization of metallophilic macrophages are normal. Thus, our study shows that CCL19/21 and its possible signaling through
CXCR3 are required for the development of thymic metallophilic macrophages, whereas the CXCL13–CXCR5 signaling is not necessary. 相似文献
176.
Yrjänäinen Alma Patrikainen Maarit S. Azizi Latifeh Tolvanen Martti E. E. Laitaoja Mikko Jänis Janne Hytönen Vesa P. Nocentini Alessio Supuran Claudiu T. Parkkila Seppo 《The protein journal》2022,41(4-5):489-503
The Protein Journal - Carbonic anhydrases (CA, EC 4.2.1.1) catalyze the hydration of carbon dioxide and take part in many essential physiological processes. In humans, 15 CAs are characterized,... 相似文献
177.
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179.
Rechardt M Shiri R Matikainen S Viikari-Juntura E Karppinen J Alenius H 《Cytokine》2011,54(2):149-153
Previous studies suggest a role for IL-1β in the pathophysiology of upper extremity soft tissue disorders (UESTDs). We studied the levels of interleukin-1 family members in patients with incipient UESTDs and compared them with healthy controls. In this case control study, we included 163 patients with UESTDs and symptom duration shorter than 1 month and 42 healthy controls matched for age and gender at the group level. Serum levels of cytokines IL-1α, IL-1β, IL-1Ra, IL-6, IL-8, IL-18, IL-33, TNFα and sensitized C-reactive protein as well as IL-1 family soluble receptors sIL-1RII and sST2 were assessed. We used unconditional logistic regression models to study the associations between cytokines and UESTDs. After adjustment for potential confounders, the serum levels of sIL-1RII (p<0.001) and sST2 (p=0.014) were higher in the patients than the controls. The level of IL-18 was lower in the patients than the controls (p=0.005). There were no significant differences between the patients and controls regarding the levels of IL-1α, IL-1β, IL-1Ra, IL-33, IL-6, IL-8, TNFα, or sensitized C-reactive protein. The levels of circulating sIL-1RII and IL-18 are associated with incipient UESTDs, suggesting an important role for these IL-1 family members in the early course of UESTDs. 相似文献
180.
Janne Valkonen Martti Niskanen Mats Björklund Johanna Mappes 《Evolutionary ecology》2011,25(5):1047-1063
European vipers (genus Vipera) are venomous and often have a distinctive dorsal zigzag pattern. The zigzag pattern of vipers has been suggested to be an example of disruptive colouration which reduces the detectability of a snake. However, recent studies suggest that the patterns have an aposematic function, although those experiments did not exclude the possibility of disruptive colouration. We used plasticine replicas of snakes to examine whether the zigzag pattern of European vipers provides protection from avian predator attacks via disruptive or aposematic function, or if the zigzag pattern might simultaneously serve both antipredatory functions. Experiments were conducted in the Coto Doñana National Park southern Spain. In the experiment, predation pressure caused by birds was compared between zigzag pattern (patterns were painted with and without disruptive effect i.e. breaking body outline or not), classical disruptive colouration (non-randomly placed patterns that breaks body outline) and control markings (replicas with length wise stripes and models without painted pattern) on natural and controlled backgrounds. We found that zigzag patterned snake replicas suffered less predation than striped ones regardless of the background, providing further evidence that the zigzag pattern of European vipers functions as a warning signal against predators. However, we did not find evidence that the zigzag pattern involves a disruptive effect. 相似文献