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排序方式: 共有106条查询结果,搜索用时 15 毫秒
1.
S Carbajo E Carbajo-Pérez J L Hernández R Vázquez J C Carvajal 《Histology and histopathology》1991,6(4):497-501
An immunocytochemical study of the epithelial lining of naturally occurring cysts in the rat intermediate lobe (IL) has been carried out. Paraffin-embedded sections, in which cysts were identifiable, were treated either with anti-serotonin or anti-S-100 protein sera. S-100-positive cells were intermingled with glandular cells surrounding the cyst lumen. These S-100-positive cells sent slender cytoplasmic processes as if to cover the apical surface of neighbouring cells. Rarely were 5-HT-immunopositive cells seen in the cyst epithelial lining. Most cells of the marginal layer of the IL were found reactive either to an S-100 or a-5-HT serum. The presence of an epithelial lining positive to S-100 protein sera is in keeping with the notion that cysts in the IL might form as evaginations of the epithelial lining of the pituitary cleft. The lack of correspondence between 5-HT-positive cells in the marginal layer and the cyst lining is controversial. A peculiar spatial relationship of 5-HT cells with the vascular network of the IL is suggested. 相似文献
2.
Jesús Rodríguez-Díaz Rodrigo J. Carbajo Antonio Pineda-Lucena Vicente Monedero María J. Yebra 《Applied and environmental microbiology》2013,79(12):3847-3850
AlfB and AlfC α-l-fucosidases from Lactobacillus casei were used in transglycosylation reactions, and they showed high efficiency in synthesizing fucosyldisaccharides. AlfB and AlfC activities exclusively produced fucosyl-α-1,3-N-acetylglucosamine and fucosyl-α-1,6-N-acetylglucosamine, respectively. The reaction kinetics showed that AlfB can convert 23% p-nitrophenyl-α-l-fucopyranoside into fucosyl-α-1,3-N-acetylglucosamine and AlfC at up to 56% into fucosyl-α-1,6-N-acetylglucosamine. 相似文献
3.
Sheree Yau Federico M Lauro Timothy J Williams Matthew Z DeMaere Mark V Brown John Rich John AE Gibson Ricardo Cavicchioli 《The ISME journal》2013,7(10):1944-1961
Organic Lake is a shallow, marine-derived hypersaline lake in the Vestfold Hills, Antarctica that has the highest reported concentration of dimethylsulfide (DMS) in a natural body of water. To determine the composition and functional potential of the microbial community and learn about the unusual sulfur chemistry in Organic Lake, shotgun metagenomics was performed on size-fractionated samples collected along a depth profile. Eucaryal phytoflagellates were the main photosynthetic organisms. Bacteria were dominated by the globally distributed heterotrophic taxa Marinobacter, Roseovarius and Psychroflexus. The dominance of heterotrophic degradation, coupled with low fixation potential, indicates possible net carbon loss. However, abundant marker genes for aerobic anoxygenic phototrophy, sulfur oxidation, rhodopsins and CO oxidation were also linked to the dominant heterotrophic bacteria, and indicate the use of photo- and lithoheterotrophy as mechanisms for conserving organic carbon. Similarly, a high genetic potential for the recycling of nitrogen compounds likely functions to retain fixed nitrogen in the lake. Dimethylsulfoniopropionate (DMSP) lyase genes were abundant, indicating that DMSP is a significant carbon and energy source. Unlike marine environments, DMSP demethylases were less abundant, indicating that DMSP cleavage is the likely source of high DMS concentration. DMSP cleavage, carbon mixotrophy (photoheterotrophy and lithoheterotrophy) and nitrogen remineralization by dominant Organic Lake bacteria are potentially important adaptations to nutrient constraints. In particular, carbon mixotrophy relieves the extent of carbon oxidation for energy production, allowing more carbon to be used for biosynthetic processes. The study sheds light on how the microbial community has adapted to this unique Antarctic lake environment. 相似文献
4.
Cabezon E Butler PJ Runswick MJ Carbajo RJ Walker JE 《The Journal of biological chemistry》2002,277(44):41334-41341
In Saccharomyces cerevisiae, at least three proteins (IF(1), STF(1), and STF(2)) appear to be involved in the regulation of ATP synthase. Both IF(1) and STF(1) inhibit F(1), whereas the proposed function for STF(2) is to facilitate the binding of IF(1) and STF(1) to F(1). The oligomerization properties of yeast IF(1) and STF(1) have been investigated by sedimentation equilibrium analytical ultracentrifugation and by covalent cross-linking. Both techniques confirm that IF(1) and STF(1) oligomerize in opposite directions in relation to pH, suggesting that both proteins might regulate yeast F(1)F(0)-ATPase under different conditions. Their effects on bovine F-ATPases are also described. Whereas bovine IF(1) inhibits yeast F(1)-ATPase even better than yeast IF(1) or STF(1), the capability of yeast IF(1) to inhibit the bovine enzyme is very low and decreases with time. Such an effect is also observed in the study of the homologous inhibition of yeast F(1)-ATPase. Yeast inhibitors are not as effective as their bovine counterpart, and the complex seems to dissociate gradually. 相似文献
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Endogenous oxytocin is released by the sow at the time of mating in response to stimulation by the boar, which may explain, at least partially, the importance of the relationship between the boar's courting activity and the subsequent reproductive performance of the sow. The aim of this study was to determine the effects on reproductive performance of supplementing AI doses with exogenous oxytocin during the low fertility season. At an intensive piggery in northwest Spain 3 experimental groups were randomly formed and observed throughout the year. Group 1 sows were inseminated with semen supplemented with 4 IU oxytocin. Group 2 sows received 4 IU oxytocin injected through the vulvar lips mucosa at the time of insemination. Group 3 sows were inseminated without oxytocin and served as the controls. During the low fertility season the results for each group were as follows: farrowing rate 77.02, 56.25 and 54.39%, and litter size 10.77 +/- 0.28, 10.45 +/- 0.31 and 8.53 +/- 0.34 respectively. It is concluded that the addition of oxytocin to seminal doses just before AI is an easily applicable, effective method for increasing fertility and litter size during the summer months. 相似文献
8.
MA Abo-El Seoud MM Sarhan AE Omar MM Helal 《Archives Of Phytopathology And Plant Protection》2013,46(3):175-184
Essential oils of fennel, peppermint, caraway, eucalyptus, geranium and lemon were tested for their antimicrobial activities against some plant pathogenic micro-organisms (Fusarium oxysporum, Alternaria alternate, Penicilium italicum Penicilium digitatum and Botyritus cinerea). Essential oils of fennel, peppermint, caraway were selected as an active ingredient for the formulation of biocides due to their efficiency in controlling the tested micro-organisms. Successful emulsifiable concentrates (biocides) were prepared from these oils using different emulsifiers (Emulgator B.L.M. Tween20 and Tween80) and different fixed oils (sesame, olive, cotton and soybean oils). Physico-chemical properties of the formulated biocide (spontaneous emulsification, emulsion stability test, cold stability and heat stability tests as well as viscosity, surface tension and pH) were measured. The prepared biocides were ready to be tested for application in a future work as a safe pesticide against different pathogens. 相似文献
9.
Gutiérrez-Abad R Carbajo D Nolis P Acosta-Silva C Cobos JA Illa O Royo M Ortuño RM 《Amino acids》2011,41(3):673-686
Two diastereomeric series of hybrid γ,γ-peptides derived from conveniently protected derivatives of (1R,2S)- and (1S,2R)-3-amino-2,2-dimethylcyclobutane-1-carboxylic acid and cis-4-amino-l-proline joined in alternation have efficiently been prepared through convergent synthesis. High-resolution NMR experiments
show that these compounds present defined conformations in solution affording very compact structures as the result of intra
and inter residue hydrogen-bonded ring formation. (R,S)-cyclobutane containing peptides adopt more twisted conformations than (S,R) diastereomers. In addition, all these γ-peptides have high tendency to aggregation providing vesicles of nanometric size,
which were stable when allowed to stand for several days, as verified by transmission electron microscopy. 相似文献
10.
A correlation between BCL-2 modifying factor,p53 and livin gene expressions in cancer colon patients
Eman AE. Badr Mohamed FA. Assar Abdel Monem A. Eltorgoman Azza Zaghlol Labeeb Gehad A. Breaka Enas A. Elkhouly 《Biochemistry and Biophysics Reports》2020
Accumulating evidence has revealed that livin gene and BCL-2 modifying factor (BMF) gene are closely associated with the initiation and progression of colon carcinoma by activating or suppressing multiple malignant processes. Those genes that can detect colon - cancer are a promising approach for cancer screening and diagnosis. This study aimed to evaluate correlation between livin, BMF and p53 genes expression in colon cancer tissues of patients included in the study, and their relationship with clinicopathological features and survival outcome in those patients. In this study, 50 pathologically diagnosed early cancer colon patients included and their tissue biopsy with 50 matched adjacent normal tissue, and 50 adenoma tissue specimens were analyzed for livin gene and BMF gene expressions using real time PCR. The relationship of those genes expressions with clinicopathological features, tumor markers, Time to Progression and overall survival for those patients were correlated in cancer colon group. In this study, there was a significant a reciprocal relationship between over expression of livin gene and down regulation of BMF and p53 genes in colon cancer cells. Livin mRNA was significantly higher, while BMF and p53 mRNA were significantly lower in colorectal cancer tissue compared to benign and normal colon tissue specimens (P < 0.001), however, this finding was absent between colon adenomas and normal mucosa. There was a significant association between up regulation of livin and down regulation of BMF and p53 expressions with more aggressive tumor (advanced TNM stage), rapid progression with metastasis and decreased overall survival in cancer colon patients, hence these genes can serve as significant prognostic markers of poor outcome in colon cancer patients. This work highlights the role of livin, BMF and p53 genes in colorectal tumorigenesis and the applicability of using those genes as a diagnostic and prognostic markers in patients with colon carcinoma and as a good target for cancer colon treatment in the future. 相似文献