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81.
International Journal of Peptide Research and Therapeutics - Natural compounds extracted from marine organisms consisting of biological active materials like collagen provide a major source of...  相似文献   
82.
Mycopathologia - Fungi of the genus Fusarium are well known as major plant pathogens but also cause a broad spectrum of human infections. Sixty-three clinical isolates, collected during...  相似文献   
83.

The interactions between sodium caseinate (NaCas) and basil seed gum (BSG) in the presence of calcium chloride (CaCl2) were investigated. The phase behavior of the mixed aqueous dispersions and their gels revealed a homogeneous mixture, obtained at the higher concentrations of both CaCl2 and BSG. The Herschel-Bulkley model sufficiently fitted the flow behavior of the mixture solution data. Apparent viscosity increased significantly (p < 0.05) by increasing the concentration of BSG, where the addition of CaCl2 had no significant effect on the viscosity of the samples (p > 0.05). Furthermore, there was an increase in thixotropy due to the higher concentrations of BSG and CaCl2. Based on the frequency sweep test, at the low frequencies, a more gel-like behavior was observed in the case of the higher concentrations of either BSG or CaCl2. The rheological and SEM data suggested that the stronger structure of NaCas-BSG gel in the presence of the higher concentrations of CaCl2 was related to the induction of complex formation between the two biopolymers.

  相似文献   
84.
85.
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels.  相似文献   
86.
Present study was designed to obtain estimation about ground water quality of Bhimber, Azad Jammu and Kashmir (AJK), Pakistan. A total of 12 water samples were collected from different localities of study area to analyze for various physicochemical and biological parameters i.e. namely temperature, pH, turbidity, color, odor, taste, electric conductivity (EC), total dissolved solids (TDS), total hardness (Calcium + Magnesium), chloride, arsenic, phosphate, lead, ammonium ion, nitrite, Fecal coliform and Escherichia coli. Results exposed that all ground water samples of study area were grossly contaminated with pathogenic microorganisms like E. coli and Fecal coliform except one water sample that was obtained from community filter plant Samahni Chowk site. Besides it, values of some physicochemical water quality determining parameters also deviated from recommended limits of World Health Organization (WHO). Chloride ion concentration was little below the prescribed limits in almost all water samples. It has been proven that consumption of un-safe drinking water is one of the major cause of prevalence of water borne diseases like diarrhea, gastroenteritis, typhoid fever and malaria etc. in study area. Community water supply and sanitation projects should be encouraged; government should provide filter plants in all regions of the country so that people could have easy approach to safe drinking water.  相似文献   
87.
Partition in aqueous dextran-polyethylene glycol two-phase systemwas used to isolate the plasma membranes from the alkalophiliccyanobacterium Spirulina platensis. The upper phase containeda colorless membranes obtained in relatively short time, 3–4h. This fraction had a different protein profile than that ofthe thylakoid fraction obtained in the lower phase. It did notcontain cytochrome c-oxidase activity, but retained characteristicMg2+-ATPase activity that is sensitive to vanadate, stimulatedby K+, and has a pH optimum near 8.5. These data support ourassumption that the upper phase of the gradient consist of theplasma membrane of S. platensis. (Received November 25, 1993; Accepted April 12, 1994)  相似文献   
88.
Coral Reefs - The Arabian Gulf is a natural laboratory to examine how subtropical coral reef ecosystems might change in responding to recurring heating events because of uniquely high water...  相似文献   
89.
Human sex hormone binding globulin (hSHBG) is a serum glycoprotein central to the transport and targeted delivery of sex hormones to steroid‐sensitive tissues. Several molecular mechanisms of action of hSHBG, including the function of its attached glycans remain unknown. Here, we perform a detailed site‐specific characterization of the N‐ and O‐linked glycosylation of serum‐derived hSHBG. MS‐driven glycoproteomics and glycomics combined with exoglycosidase treatment were used in a bottom‐up and top‐down manner to determine glycosylation sites, site‐specific occupancies and monosaccharide compositions, detailed glycan structures, and the higher level arrangement of glycans on intact hSHBG. It was found that serum‐derived hSHBG is N‐glycosylated at Asn351 and Asn367 with average molar occupancies of 85.1 and 95.3%, respectively. Both sites are occupied by the same six sialylated and partly core fucosylated bi‐ and triantennary N‐Glycoforms with lactosamine‐type antennas of the form (±NeuAcα6)Galβ4GlcNAc. N‐Glycoforms of Asn367 were slightly more branched and core fucosylated than Asn351 N‐glycoforms due probably to a more surface‐exposed glycosylation site. The N‐terminal Thr7 was fully occupied by the two O‐linked glycans NeuAcα3Galβ3(NeuAcα6)GalNAc (where NeuAc is N‐acetylneuraminic acid and GalNAc is N‐acetylgalactosamine) and NeuAcα3Galβ3GalNAc in a 1:6 molar ratio. Electrophoretic analysis of intact hSHBG revealed size and charge heterogeneity of the isoforms circulating in blood serum. Interestingly, the size and charge heterogeneity were shown to originate predominantly from differential Asn351 glycan occupancies and N‐glycan sialylation that may modulate the hSHBG activity. To date, this work represents the most detailed structural map of the heterogeneous hSHBG glycosylation, which is a prerequisite for investigating the functional aspects of the hSHBG glycans.  相似文献   
90.
Sayed  Mohammed A  Schumann  Henrik  Pillen  Klaus  Naz  Ali A  Léon  Jens 《BMC genetics》2012,13(1):1-12

Background

Phytophthora infestans (Mont.) de Bary, the causal organism of late blight, is economically the most important pathogen of potato and resistance against it has been one of the primary goals of potato breeding. Some potentially durable, broad-spectrum resistance genes against this disease have been described recently. However, to obtain durable resistance in potato cultivars more genes are needed to be identified to realize strategies such as gene pyramiding or use of genotype mixtures based on diverse genes.

Results

A major resistance gene, Rpi-rzc1, against P. infestans originating from Solanum ruiz-ceballosii was mapped to potato chromosome X using Diversity Array Technology (DArT) and sequence-specific PCR markers. The gene provided high level of resistance in both detached leaflet and tuber slice tests. It was linked, at a distance of 3.4 cM, to violet flower colour most likely controlled by the previously described F locus. The marker-trait association with the closest marker, violet flower colour, explained 87.1% and 85.7% of variance, respectively, for mean detached leaflet and tuber slice resistance. A genetic linkage map that consisted of 1,603 DArT markers and 48 reference sequence-specific PCR markers of known chromosomal localization with a total map length of 1204.8 cM was constructed.

Conclusions

The Rpi-rzc1 gene described here can be used for breeding potatoes resistant to P. infestans and the breeding process can be expedited using the molecular markers and the phenotypic marker, violet flower colour, identified in this study. Knowledge of the chromosomal localization of Rpi-rzc1 can be useful for design of gene pyramids. The genetic linkage map constructed in this study contained 1,149 newly mapped DArT markers and will be a valuable resource for future mapping projects using this technology in the Solanum genus.  相似文献   
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