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排序方式: 共有349条查询结果,搜索用时 31 毫秒
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The paper presents the effect of in vivo immuno-neutralization of porcine luteinizing hormone (pLH) by species-homologous porcine antiserum (anti-pLH) administrations on pregnancy maintenance and immunodetection of the PAG proteins in precipitated plasma proteins of pregnant gilts. Pregnant gilts were passively immunized with 100 ml of porcine anti-pLH (titer 1:10 000) by multiple intravenous infusions performed from 37(th) to 42(nd) day post coitum (dpc; 12-h intervals). Blood samples of pregnant gilts were taken 12 times daily from 35 until 50 dpc. Concentrations of progesterone (P(4)) and pLH were determined by radioimmunoassays in systemic blood plasma of treated gilts and control pregnant gilts. The immuno-neutralization of peripheral pLH with the use of homologous anti-pLH serum resulted in a significant reduction (p<0.001) of plasma P(4) concentrations in two out of six treated gilts only, but abortion did not occur. In the remaining four passively immunized pregnant gilts, plasma P(4) concentration was increased (p<0.001) and the abortion occurred (47 dpc) only in one of the gilts. In addition, various anti-pPAG sera were purified by sequential adsorptions with endometrial proteins of cyclic gilts. Western blotting demonstrated the expression of the PAG proteins in precipitated plasma proteins of pregnant gilts. In conclusion, the passive immuno-neutralization of porcine LH by species-homologous antiserum (anti-pLH) did not affect the pregnancy maintenance. Thus, the maintenance of mid-pregnancy in gilts may depend also on other than LH luteotrophic factors. In addition, Western analysis of precipitated plasma proteins of pregnant pigs suggests a role of the PAG family during pregnancy in the pig. 相似文献
325.
Mohamadreza Najiminaini Fartash Vasefi Bozena Kaminska Jeffrey J. L. Carson 《Plasmonics (Norwell, Mass.)》2013,8(2):217-224
We report a 3D plasmonic nanostructure having an extraordinary optical transmission due to localized surface plasmon (LSP) coupling between nanoholes and nanodisks. The nanostructure contains a free-standing gold nanohole array (NHA) film above a cavity and an array of nanodisks at the bottom of the cavity that is aligned with the NHA. For the device, the LSP-mediated resonance position was dependent on the hole and nanodisk diameter as well as the separation distance. Also, the effect of LSP coupling between each hole and corresponding nanodisk became negligible for cavities deeper than 200 nm as observed as a disappearance of the LSP resonance. The greatest LSP resonance transmission and the highest electric field intensity were observed for the structure with the shallowest cavity. In addition, the structure had high surface plasmon resonance sensitivity and may have potential for surface-enhanced Raman spectroscopy and optical trapping applications. 相似文献
326.
Krzysztof Wanic Bozena Krolewski Wenjun Ju Grzegorz Placha Monika A. Niewczas William Walker James H. Warram Matthias Kretzler Andrzej S. Krolewski 《PloS one》2013,8(3)
Background
In patients with Type 1 Diabetes (T1D) who develop microalbuminuria, progressive decline in glomerular filtration rate (GFR) may be initiated by leakage into the urine of toxic proteins (txUPs). This study tested this hypothesis.Methods
After archiving baseline urine, we followed T1D patients with microalbuminuria for 8–12 years to distinguish those in whom GFR declined (Decliners) and those in whom it remained stable (Non-decliners). Human proximal tubular cells (HK-2 cells) were grown in serum-free medium enriched with pooled urines from Decliners or Non-decliners. We determined genome-wide expression profiles in extracted mRNA.Results
The two pooled urines induced differential expression of 312 genes. In terms of gene ontology, molecular functions of the 119 up-regulated genes were enriched for protein binding and peptidase inhibitor activities. Their biologic processes were enriched for defense response, responses to other organisms, regulation of cellular processes, or response to stress or stimulus, and programmed cell death. The 195 down-regulated genes were disproportionately represented in molecular functions of cation binding, hydrolase activity, and DNA binding. They were disproportionately represented in biological processes for regulation of metabolic processes, nucleic acid metabolic processes, cellular response to stress and macromolecule biosynthesis. The set of up-regulated genes in HK-2 cells overlaps significantly with sets of over-expressed genes in tubular and interstitial compartments of kidney biopsies from patients with advanced DN (33 genes in one study and 25 in the other compared with 10.3 expected by chance, p<10−9 and p<10−4, respectively). The overlap included genes encoding chemokines and cytokines. Overlap of down-regulated genes was no more than expected by chance.Conclusions
Molecular processes in tubules and interstitium seen in advanced diabetic nephropathy can be induced in vitro by exposure to urine from patients with minimal microalbuminuria who subsequently developed progressive renal function decline, presumably due to putative txUPs. 相似文献327.
Photodynamic therapy (PDT) is based on photosensitizers activated by light of appropriate wavelength. Their activation leads to generation of singlet oxygen and free radicals responsible for the cytotoxic effect. The aim of this project was to compare the bactericidal effect of PDT using different porphyrin photosensitizers against a methicillin-resistant Staphylococcus aureus strain. Exogenous sensitizers (protoporphyrin IX and newly synthesized derivative, protoporphyrin diarginate) induced a 3 log10-unit reduction in bacterial viable counts. With the use of endogenous, ALA-induced porphyrins, a 1.6 log10-unit reduction was obtained. The sensitizers tested executed their antibacterial activity with no essential change in the antibiotic resistance pattern of the studied strain. 相似文献
328.
Expression of genes encoding mitochondrial proteins can distinguish nonalcoholic steatosis from steatohepatitis 总被引:1,自引:0,他引:1
Bragoszewski P Habior A Walewska-Zielecka B Ostrowski J 《Acta biochimica Polonica》2007,54(2):341-348
In patients without substantial alcohol use, triglyceride accumulation in the liver can lead to nonalcoholic fatty liver disease (NAFLD) that may progress to nonalcoholic steatohepatitis (NASH). The differential diagnosis between NAFLD and NASH can be accomplished only by morphological examination. Although the relationship between mitochondrial dysfunction and the progression of liver pathologic changes has been described, the exact mechanisms initiating primary liver steatosis and its progression to NASH are unknown. We selected 16 genes encoding mitochondrial proteins which expression was compared by quantitative RT-PCR in liver tissue samples taken from patients with NAFLD and NASH. We found that 6 of the 16 examined genes were differentially expressed in NAFLD versus NASH patients. The expression of hepatic HK1, UCP2, ME2, and ME3 appeared to be higher in NASH than in NAFLD patients, whereas HMGCS2 and hnRNPK expression was lower in NASH patients. Although the severity of liver morphological injury in the spectrum of NAFLD-NASH may be defined at the molecular level, expression of these selected 6 genes cannot be used as a molecular marker aiding histological examination. Moreover, it is still unclear whether these differences in hepatic gene expression profiles truly reflect the progression of morphological abnormalities or rather indicate various metabolic and hormonal states in patients with different degrees of fatty liver disease. 相似文献
329.
Kosztyla-Hojna B Andrzejewska A Rutkowski R Rogowski M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2007,45(3):221-227
The voice quality in prebysphonia is conditioned by morphological changes in the vocal folds mucosa. The studies including light microscopy and transmission electron microscopy (TEM) revealed changes within the basal membrane epithelium and the stroma of the vocal folds mucosa. Age-related changes in thickness of the epithelium and direction of the basal membrane, increased number of collagenous fibres (C) and fibroblasts and chronic inflammatory process in the stroma were found. Vacuolated and keratinised epithelial cells, enlarged extracellular spaces and numerous blood vessels confirm the edematous form of prebysphonia. Thinned epithelium with signs of hyalinization, inflammatory infiltrations in the stroma with numerous collagenous fibres and small number of blood vessels indicate atrophy of the vocal folds mucosa. Edematous and atrophic changes in the vocal folds mucosa are most frequently reported form of prebysphonia. 相似文献
330.
Lena Innala Ewa Berglin Bozena M?ller Lotta Ljung Torgny Smedby Anna S?dergren Staffan Magnusson Solbritt Rantap??-Dahlqvist Solveig W?llberg-Jonsson 《Arthritis research & therapy》2014,16(2):R94