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1.
A S Saber 《Acta morphologica Neerlando-Scandinavica》1987,25(3):173-185
The venous drainage of the kidney of the one-humped camel (Camelus dromedarius) was studied in 17 kidneys of male and female adult animals. Injection of latex, plastoid as well as radiopaque substance (40% barium sulfate) were used to follow the distribution of the renal vein through the kidney tissue. The renal vein of the camel is unique as it gives off vv. interlobares I which drain the ventral half of the kidney, in addition to large cranial and caudal stem vessels from which vv. interlobares I of the dorsal surface branch. The general pattern of distribution of the renal vein in the camel's kidney resembles, more or less, that of the other domestic animals. 相似文献
2.
Thirty-nine species and 16 fungal genera were isolated from Egyptian cotton seeds, cotton seed meal and cotton seed cake on 1% glucose-Czapek's agar medium incubated at 28 °C. Aspergillus was the most frequent genus and it emerged in 87–100% of the samples contributing 70–98% of total fungi in the three substrates tested. The most common species were A. niger, A. flavus, A. fumigatus, A. terreus and Rhizopus stolonifer; A. niger, A. fumigatus and Penicillium corylophilum; and A. niger, A. flavus, A. terreus, A. nidulans and Rhizopus stolonifer, respectively. Cotton seeds and cotton seed products were naturally contaminated by aflatoxin B1 and B2. About 16% of the different substrates tested were positive for aflatoxin contamination. No citrinin, ochratoxin A, patulin, sterigmatocystin, diacetoxyscirpenol, T-2 toxin or zearalenone were detected in the samples assayed. 相似文献
3.
Changes in collagen and albumin mRNA in liver tissue of mice infected with Schistosoma mansoni as determined by in situ hybridization 总被引:5,自引:0,他引:5 下载免费PDF全文
We have employed in situ hybridization to evaluate the molecular mechanisms responsible for hypoalbuminemia and increased liver collagen content in murine schistosomiasis. Results were compared using a simplified method of hybridizing isolated hepatocytes from Schistosoma mansoni-infected and normal mouse liver with mouse albumin (pmalb-2) and chick pro-alpha 2(l) collagen (pCg45) probes. Whereas hepatocytes from infected mice showed significantly less albumin mRNA than hepatocytes from control, there were more grains of procollagen mRNA in hepatocytes from infected as compared with control liver. Hybridization of infected liver tissue sections with the collagen probe showed more grains per field in granulomas than in liver regions, whereas with the albumin probe there was more hybridization in liver tissue than in granulomas. These results suggest that in murine schistosomiasis a reduction in albumin mRNA sequence content may be associated with decreased albumin synthesis and ultimately leads to hypoalbuminemia. In addition, although the granuloma seems to be the primary source of type I collagen synthesis, hepatocytes are also capable of synthesizing collagen, especially under fibrogenic stimulation. 相似文献
4.
Given the current interest in potential carcinogenic and developmental effects of exposure to extremely-low-frequency electromagnetic fields, there is a need to identify cohorts of exposed female workers for future epidemiologic investigations. This study was designed to test the hypothesis that nurses working in neonatal intensive care units (NICU) may be significantly exposed to power-frequency magnetic fields. An electromagnetic field monitor was used to measure magnetic fields at distances of 5, 15, 30, and 60 cm from the surfaces of each device used in the NICU. Six female nurses assigned to the NICU (the “exposed” group) and six female nurses working in the normal newborn nursery (the “referent” group) wore EMDEX dosimeters for the entire duration of their 12 h shifts. An investigator kept a detailed log of each NICU subject's whereabouts for the first one-third of her shift. Magnetic fields at 5 cm from the front (defined by the nurses' usual work area) of the NICU devices ranged from less than 0.1 to 114 μT and in all cases decreased considerably with increasing distance. The geometric mean of the shift-time-weighted average exposure of the NICU nurses was 0.17 μT compared with 0.11 μT for the normal newborn nurses. The percentage of time when subjects were exposed to magnetic fields of 0.4 μT or greater ranged from 5.8% to 15.6% for the NICU nurses, 0.4% to 2.9% for five of the comparison group nurses, and was 9.4% for one of the normal newborn nurses with unidentified aberrantly high exposures. Log data revealed that the vast majority of observed peaks among NICU nurses occurred while subjects were in close proximity to infant bed units. We conclude that NICU nurses represent one female-intensive job sector with intermittent high exposures to ELF magnetic fields and encourage larger exposure studies of nurses in a variety of medical settings. © 1994 Wiley-Liss, Inc. 相似文献
5.
One hundred isolates of 27 species belonging to 13 genera of dematiaceous hyphomycetes were screened for production of cytochalasins A and B. Most of these isolates (94) were obtained from Assiut University Culture Collection, Botany Department, Faculty of Science, Assiut University, Egypt; three isolates from CBS, The Netherlands; two isolates from DSM, Germany; and one isolate from IMI, UK. The results revealed that 10 isolates of six species representing five genera of fungi produced cytochalasins A and/or B. These species are Alternaria chlamydospora, Cochliobolus spicifer, Diplococcum spicatum, Phoma herbarum, Phoma multipara and Setosphaeria rostrata. This is the first report for the production of cytochalasins A and/or B by these species of dematiaceous hyphomycetes. 相似文献
6.
A series of aroyl- and aryl-hydrazide derivatives was prepared from d-glycero-d-gulo-heptono-1,4-lactone (1). The reactivity of the NH proton in these hydrazides, in terms of their dissociation constants (pKa), was determined from their electronic spectra, and correlated to the Hammett σ values of the substituents. Comparable reactivities of the NH protons for the compounds, and the effect of the substituent, were studied by n.m.r. spectroscopy. Decomposition of the aroylhydrazides with copper(II) sulfate or nitrous acid resulted in the regeneration of 1. 相似文献
7.
Sassan Saber Reza Vazifehmand Iman Bagherizadeh Mahbubeh Kasiri 《Indian journal of human genetics》2013,19(3):366-368
Progressive familial intrahepatic cholestasis is an autosomal recessive liver disorder caused by (biallelic) mutations in the ATP8B1 of ABCB11 gene. A nine-year-old girl with cholestasis was referred for genetic counseling. She had a family history of cholestasis in two previous expired siblings. Genetic analysis of the ABCB11 gene led to the identification of a novel homozygous mutation in exon 25. The mutation 3593- A > G lead to a missense mutation at the amino acid level (His1198Arg). This mutation caused PFIC2 due to abnormal function in the bile salt export pump protein (BSEP). 相似文献
8.
Plasmonics - Polarization reconfigurable dielectric resonator antenna (DRA) backed by plasma artificial magnetic conductor (AMC) ground plane is designed and optimized for 10-GHz applications. The... 相似文献
9.
Aliasghar Bahari Sakineh Azami Ali Goudarztalejerdi Saeid Karimi Saber Esmaeili Bruno B. Chomel Alireza Sazmand 《The Yale journal of biology and medicine》2021,94(2):249
Dromedary camels (Camelus dromedarius) play a major economic role in many countries in Africa and Asia. Although they are resistant to harsh environmental conditions, they are susceptible to a wide range of zoonotic agents. This study aimed to provide an overview on the prevalence of selected zoonotic pathogens in blood and tissues of camels in central Iran. Blood, liver, portal lymph node, and brain were collected from 100 apparently healthy camels at a slaughterhouse in Qom city to assess the presence of DNA of Brucella spp., Trypanosoma spp., Coxiella burnetii, and Bartonella spp. PCR products were sequenced bidirectionally and phylogenetic analyses were performed. Eleven percent of camels tested positive for Brucella abortus (3%) and Trypanosoma evansi (8%). Coxiella burnetii and Bartonella spp. DNA was not detected. Our data demonstrate that camels from Iran contribute to the epidemiology of some zoonotic pathogens. Performing proper control strategies, such as vaccination of camels and humans in contact with them, test-and-slaughter policy, and education of the general population is necessary for minimizing the risk of zoonotic infection. 相似文献
10.
Molecular Biology Reports - 相似文献