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71.
The current study was conducted to reveal the current states, structural features and primary problems of the sheep raising businesses in the city of U?ak. The study group of the current study is comprised of 429 sheep raising businesses selected through stratified sampling (provinces) and a questionnaire consisted of 112 items was administered to these businesses. Through the items in the questionnaire, data were collected about the general features of the businesses and their owners, the state of grazing lands, mating of sheep, birth, milking, clipping, health protection, marketing of animals and the states of tools and equipments in the businesses.The findings of the study have revealed that 82.2% of the owners of the sheep raising businesses are elementary school graduates, their average time of being involved in the activity of sheep raising is 9.8?years, 90% of their shepherds are from the family members, 23.5% of them practice additional feeding before mating and the most preferred method for mating is free insemination with 89%.Of the owners of the businesses, 81.1% learned sheep raising from their elders; for 54% of them sheep raising is the sole source of income and 25.6% of them are engaged in sheep raising to support their families. The main problems of the sheep raisers were found to be the high cost of feed, the low prices paid for their products, inadequate and poor quality grazing lands and animal diseases. In order to make sheep raising more attractive, the prices of the products should be increased, grazing lands should be improved, the genetic structure of the herd should be enhanced, the amount of land area where feed crops are cultivated should be extended and suitable credit conditions should be provided. On the other hand, they need to be informed about sheep mating, lamb growing, stock, milking hygiene, general sheep feeding practices and marketing.  相似文献   
72.
Phage display is one of the most widely used technology for antibody discovery and engineering. Number of therapeutic antibodies derived from phage display increases rapidly due to its ease of use and ability to control antibody sequence information. Although there are numerous antibody candidates as promising therapeutics, most of them fail at later stages of development due to undesired biophysical properties. Antibody candidates with poor properties should be prevented or improved in early development phases to minimize enormous loss of time and resources. In this study, we showed that phage display derived therapeutic antibodies show higher self-interaction and polyspecificity compared to non-phage display derived ones. To identify molecular determinants behind this, physicochemical properties of CDR regions of 137 therapeutic antibodies were analyzed. We found multiple significant differences in both heavy and light chain CDR regions. Most profoundly, aliphatic content of HCDR3, HCDR2, and LCDR3 regions were enriched in phage display derived antibodies compared to non-phage display derived ones. Physicochemical determinants documented here seem to play important roles in polyspecific and aggregation-prone natures of antibodies which should be avoided in early development phases.  相似文献   
73.
Activated factor XI (FXIa) inhibitors are anticipated to combine anticoagulant and profibrinolytic effects with a low bleeding risk. This motivated a structure aided fragment based lead generation campaign to create novel FXIa inhibitor leads. A virtual screen, based on docking experiments, was performed to generate a FXIa targeted fragment library for an NMR screen that resulted in the identification of fragments binding in the FXIa S1 binding pocket. The neutral 6-chloro-3,4-dihydro-1H-quinolin-2-one and the weakly basic quinolin-2-amine structures are novel FXIa P1 fragments. The expansion of these fragments towards the FXIa prime side binding sites was aided by solving the X-ray structures of reported FXIa inhibitors that we found to bind in the S1-S1’-S2’ FXIa binding pockets. Combining the X-ray structure information from the identified S1 binding 6-chloro-3,4-dihydro-1H-quinolin-2-one fragment and the S1-S1’-S2’ binding reference compounds enabled structure guided linking and expansion work to achieve one of the most potent and selective FXIa inhibitors reported to date, compound 13, with a FXIa IC50 of 1.0 nM. The hydrophilicity and large polar surface area of the potent S1-S1’-S2’ binding FXIa inhibitors compromised permeability. Initial work to expand the 6-chloro-3,4-dihydro-1H-quinolin-2-one fragment towards the prime side to yield molecules with less hydrophilicity shows promise to afford potent, selective and orally bioavailable compounds.  相似文献   
74.
Demir  Ahmet U.  Ardic  Sadik  Firat  Hikmet  Karadeniz  Derya  Aksu  Murat  Ucar  Zeynep Zeren  Sevim  Serhan  Ozgen  Fuat  Yilmaz  Hikmet  Itil  Oya  Peker  Yuksel  Aygul  Fatma  Kiran  Sibel  Gelbal  Selahattin  Cepni  Zafer  Akozer  Mehmet 《Sleep and biological rhythms》2015,13(4):298-308
Sleep and Biological Rhythms - Sleep disorders constitute an important public health problem. Prevalence of sleep disorders in Turkish adult population was investigated in a nationwide...  相似文献   
75.
There is growing evidence that shift-work schedules cause severe disturbances to circadian rhythms and the sleep–wakefulness cycle, and that these changes in turn lead to cognitive and behavioral problems. The objective of this study is to explore the relationships between biological rhythm differences (chronotype) and impulsive behaviors and attention-deficit hyperactivity symptoms in shift workers. Seventy-nine nurses working in the daytime and 127 nurses working on night shifts were evaluated with the Barratt Impulsiveness Scale, Adult Attention Deficit Hyperactivity Disorder Self-Report Scale (ASRS), and Morningness–Eveningness questionnaire for identifying circadian preference. It was found that shift workers had more attention deficit (p < .05) and impulsivity (p < .01) when compared with daytime workers. Morning-type workers reported lower hyperactivity and ASRS total scores than evening- and intermediate-type workers. The mean impulsivity score of evening-type workers was higher than both the other groups (p < .05). It has been shown that attention deficit, hyperactivity, and impulsivity levels that appear as a result of working shifts might change in accordance with the individual’s chronotype. It might, therefore, be desirable to evaluate an individual’s chronotype to establish suitability for working shifts.  相似文献   
76.
Plant Cell, Tissue and Organ Culture (PCTOC) - Diosgenin is an important precursor of steroidal drugs and a number of biotechnology techniques, including gene transfer and elicitation studies, are...  相似文献   
77.
78.
Acetylcholinesterase (AChE), encoded by the Ace gene, is the primary target of organophosphates (OPs) and carbamates (CBs) in insects. Ace mutations have been identified in OP and CB resistant strains of Musca domestica. In this study, the Ace gene was partially amplified and sequenced at amino acid positions 260, 342, and 407 to determine the frequencies of these mutations in housefly samples collected from farms and garbage disposal sites of 16 provinces in the Aegean and Mediterranean regions of Turkey. In addition, the percent remaining AChE activities in these samples were assayed by using three OPs (malaoxon, paraoxon, and dichlorvos) and one CB (carbaryl) compound as inhibitors. In all the analyzed samples, 13 different combinations at the three amino acid positions were identified and the L/V260-A/G342-F/Y407 combination was found in the highest frequency. No susceptible individual was detected. The highest mean percent remaining AChE activities were detected in the individuals having the L260-A/G342-F/Y407 genotype when malaoxon and paraoxon were used as inhibitors and in the individuals with the L260-A342-F/Y407 combination when dichlorvos and carbaryl were used as inhibitors. The obtained data were heterogeneous and there was no exact correlation between the molecular genetic background and the resistance phenotypes of the flies. The findings of this study at the molecular and biochemical levels indicate the presence of significant control problems in the field.  相似文献   
79.
80.
We investigated the interactions between snowpack chemistry, mercury (Hg) contamination and microbial community structure and function in Arctic snow. Snowpack chemistry (inorganic and organic ions) including mercury (Hg) speciation was studied in samples collected during a two-month field study in a high Arctic site, Svalbard, Norway (79°N). Shifts in microbial community structure were determined by using a 16S rRNA gene phylogenetic microarray. We linked snowpack and meltwater chemistry to changes in microbial community structure by using co-inertia analyses (CIA) and explored changes in community function due to Hg contamination by q-PCR quantification of Hg-resistance genes in metagenomic samples. Based on the CIA, chemical and microbial data were linked (p = 0.006) with bioavailable Hg (BioHg) and methylmercury (MeHg) contributing significantly to the ordination of samples. Mercury was shown to influence community function with increases in merA gene copy numbers at low BioHg levels. Our results show that snowpacks can be considered as dynamic habitats with microbial and chemical components responding rapidly to environmental changes.  相似文献   
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