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1.
HLA-C alleles were characterized by a polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) hybridization protocol in a sample of 120 Iranians from Tehran. A total of 23 alleles were identified with the four most predominant--Cw*0401, Cw*0602, Cw*1202, and Cw*0701/06--accounting for almost 50% of HLA-C alleles. A comparison of HLA-C diversity among several populations indicates that Iranians stand at an intermediate genetic position between Europeans and Africans, an observation that may be related to their geographical location at a continental crossroads. The results also reveal a very high correlation between genetic and geographic distances on a global scale. A total of 30 HLA-C-DRB1 haplotypes were found in the Iranians, with the highest frequencies of 6.6% and 6.04 % being for Cw*0602-DRB1*0701 and Cw*1202-DRB1*1502, respectively.  相似文献   

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Single nucleotide polymorphisms within the promoter or other regulatory sequences of cytokine genes were evaluated and compared between an Iranian population and populations of different ethnic/geographical background. In 40 healthy Iranian subjects, cytokine typing was performed by polymerase chain reaction-sequence-specific primers assay. Allele frequencies were calculated and compared with those of other populations.  相似文献   

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The human recombinant HLA-DRB1 gene probe was used for histocompatibility typing of two families of beagles for the DLA-D equivalent by using restriction fragment length polymorphisms (RFLP). This method was able to determine the segregation of these genes from the parental animals to the individual F1 offspring. Mixed lymphocyte culture (MLC) reactivity as well as serological typing for class I histocompatibility antigens were also performed for comparison. It was found that there was a high correlation between these three methods. We therefore conclude that RFLP typing is an effective procedure for predicting MLC reactivity in dogs and propose that it is a suitable genotyping method for assignment of class II antigen compatibility for donor-recipient pairs in conjunction with organ transplant studies.  相似文献   

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Bacteria were isolated from the dental plaques of nine dogs and a sample of pooled saliva from five other dogs and were then identified by comparative 16S rRNA gene sequencing. Among 339 isolates, 84 different phylotypes belonging to 37 genera were identified. Approximately half of the phylotypes were identified to the species level, and 28% of these were considered members of the indigenous oral microbiota of humans. The 16S rRNA gene sequences of the remaining 44 phylotypes were not represented in GenBank, and most of these phylotypes were tentatively identified as candidate new species. The genera most frequently isolated from saliva were Actinomyces (26%), Streptococcus (18%), and Granulicatella (17%). The genera most frequently isolated from plaque were Porphyromonas (20%), Actinomyces (12%), and Neisseria (10%). A comparison of the DNA sequences from this study with sequences of the human microbiota available in GenBank showed that, on average, canine and human microbiotas differed by almost 7% in the 16S rRNA gene. In conclusion, this study has shown that the cultivable oral microbiotas of dogs and humans show significant differences.  相似文献   

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Considering the application of human genome variation databases in precision medicine, population‐specific genome projects are continuously being developed. However, the Middle Eastern population is underrepresented in current databases. Accordingly, we established Iranome database ( www.iranome.com ) by performing whole exome sequencing on 800 individuals from eight major Iranian ethnic groups representing the second largest population of Middle East. We identified 1,575,702 variants of which 308,311 were novel (19.6%). Also, by presenting higher frequency for 37,384 novel or known rare variants, Iranome database can improve the power of molecular diagnosis. Moreover, attainable clinical information makes this database a good resource for classifying pathogenicity of rare variants. Principal components analysis indicated that, apart from Iranian‐Baluchs, Iranian‐Turkmen, and Iranian‐Persian Gulf Islanders, who form their own clusters, rest of the population were genetically linked, forming a super‐population. Furthermore, only 0.6% of novel variants showed counterparts in “Greater Middle East Variome Project”, emphasizing the value of Iranome at national level by releasing a comprehensive catalog of Iranian genomic variations and also filling another gap in the catalog of human genome variations at international level. We introduce Iranome as a resource which may also be applicable in other countries located in neighboring regions historically called Greater Iran (Persia).  相似文献   

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In humans, chronic infection with the gammaherpesvirus Epstein-Barr virus is usually asymptomatic; however some infected individuals develop hematological and epithelial malignancies. The exact role of EBV in lymphomagenesis is poorly understood partly because of the lack of clinically relevant animal models. Here we report the detection of serological responses against EBV capsid antigens in healthy dogs and dogs with spontaneous lymphoma and that dogs with the highest antibody titers have B cell lymphoma. Moreover, we demonstrate the presence of EBV-like viral DNA and RNA sequences and Latent Membrane Protein-1 in malignant lymph nodes of dogs with lymphoma. Finally, electron microscopy of canine malignant B cells revealed the presence of classic herpesvirus particles. These findings suggest that dogs can be naturally infected with an EBV-like gammaherpesvirus that may contribute to lymphomagenesis and that dogs might represent a spontaneous model to investigate environmental and genetic factors that influence gammaherpesvirus-associated lymphomagenesis in humans.  相似文献   

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The bending strength of the upper canine tooth is analyzed on 51 domestic dogs of various breeds. Data show that canine tooth length is greater among small domestic dogs when compared to small wild dogs, and large wild dogs when compared among large domestic dogs. Tooth strength is also greater among small domestic dogs and large wild dogs. The greater tooth strength of the small domestic dogs may be attributed to the idea that small domestic dogs are closer in ancestry to the grey wolf (Canis lupus) than are small wild canids. Skull foreshortening and tooth strength appear to be correlated in the canidae.  相似文献   

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Introduction: Looking to the applied significance of lumbar plexus in the form of its involvement in various injuries, direct or iatrogenic and entrapment, it is imperative to have a thorough knowledge about its formation, branching pattern, and variations. Tubbs et al referred to the lumbar plexus as a ‘no man's land’ because of relative inaccessibility of this region and there is infrequency in operating on retroperitoneal structures by neurosurgeons. However, a recent increase in retroperitoneal laparoscopic surgeries inspired us to revisit the anatomy of lumbar plexus. Material and methods: The study was conducted on 30 formalin embalmed cadavers available in the Department of Anatomy, RMC, PIMS, Loni, Maharashtra. Thorough dissection was performed to observe the formation of branches of lumbar plexus and measurements were taken from the adjacent bony landmarks. Result: Bilateral prefixation of the lumbar plexus was found in one cadaver bilaterally. Ilioinguinal and iliohypogastric nerves were arising by a common stem in 11.66% of cases; in the remaining ones, they were having separate origins. In majority, 81.6% of the genitofemoral nerve pierced the medial third of the anterior surface of the psoas major muscle. Accessory obturator nerve was observed in 3 cases (5%) of 60 plexuses. The site of formation of femoral nerve was 5 cm inferior to the iliac crest in 71.6% of instances. The formation of obturator nerve was found to vary from the level of supracristal plane to 3.5 cm inferior to the plane; in 58.3%, it was 3 cm below the plane. Conclusion: The measurements given in this study will help the surgeon to avoid iatrogenic nerve injury as well as to assess them during lumbar plexus block.  相似文献   

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Domestic dogs, Canis lupus, have been one of the longest companions of humans and have introduced their own menagerie of parasites and pathogens into this relationship. Here, we investigate the parasitic load of 212 domestic dogs with fleas (Siphonaptera) chewing lice (Phthiraptera), and ticks (Acarina) along a gradient from rural areas with near-natural forest cover to suburban areas in Northern Borneo (Sabah, Malaysia). We used a spatially-explicit hierarchical Bayesian model that allowed us to impute missing data and to consider spatial structure in modelling dog infestation probability and parasite density. We collected a total of 1,968 fleas of two species, Ctenocephalides orientis and Ctenocephalides felis felis, from 195 dogs (prevalence, 92 %). Flea density was higher on dogs residing in houses made of bamboo or corrugated metal (increase of 40 % from the average) compared to timber or stone/compound houses. Host-dependent and landscape-level environmental variables and spatial structure only had a weak explanatory power. We found adults of the invasive chewing louse Heterodoxus spiniger on 42 dogs (20 %). The effect of housing conditions was opposite to those for fleas; lice were only found on dogs residing in stone or timber houses. We found ticks of the species Rhipicephalus sanguineus as well as Haemaphysalis bispinosa gp., Haemaphysalis cornigera, Haemaphysalis koenigsbergi, and Haemaphysalis semermis on 36 dogs (17 %). The most common tick species was R. sanguineus, recorded from 23 dogs. Tick infestations were highest on dogs using both plantation and forest areas (282 % increase in overall tick density of dogs using all habitat types). The infestation probability of dogs with lice and ticks decreased with elevation, most infestations occurred below 800 m above sea level. However, the density of lice and ticks revealed no spatial structure; infestation probability of dogs with these two groups revealed considerable autocorrelation. Our study shows that environmental conditions on the house level appeared to be more influential on flea and lice density whereas tick density was also influenced by habitat use. Infestation of dogs with Haemaphysalis ticks identified an important link between dogs and forest wildlife for potential pathogen transmission.  相似文献   

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The process of domestication is complex and results in significant morphological, cognitive, and physiological changes. In canids, some of the traits indicative of domestication of domestic dogs compared to their wild counterparts the wolves are prosociality toward humans, reduced stress hormone levels, and reduced cranial capacity. Research suggests that selection for prosociality among dogs resulted in morphological changes such as reduction in cranial capacity, juvenilization of the face, and overall gracile morphology. Interestingly, similar features have been described in modern humans compared to extinct species of Homo, for example, Neanderthals. Therefore, the human self-domestication hypothesis has been proposed to partially explain the gracile modern human skeleton. Specifically, that as modern humans settled in communities, there was increased selection for prosociality (intergroup cooperation); and one of the by-products of this selection was the evolution of a gracile skeleton, including a slight reduction in cranial capacity, reduced brow ridge and tooth size, and low trabecular bone fraction (TBF). However, TBF variation has not been tested between domestic dogs and wolves, who underwent self-domestication. Thus, this study tests the hypothesis that dogs have low TBF as a consequence of domestication compared to their wild counterparts, the wolves, by comparing TBF in the hindlimbs—proximal femur and distal tibia- of the two species. Wilcoxon rank sum tests show that dogs have lower TBF values than wolves in both elements. These preliminary results add to the literature documenting changes in self-domesticated species and provide a potential analog to further the understanding of self-domestication.  相似文献   

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The microscopic anatomy of the atrioventricular node, bundle of His, both bundle branches and surrounding fibrous cardiac skeleton was studied in 40 large breed dogs of various ages. In the AV conduction system of all dogs over five years of age there was an increase of fibrous connective tissue, an infiltration of adipose tissue, loss of conduction fibers and focal fibrosis extending from the central fibrous body. Fibrosis was seen in the summit of the interventricular septum posterior to the AV node in dogs of all ages. Chondroid metaplasia was consistently observed in the central fibrous body and the root of the aorta in large breed dogs, including ten Doberman Pinschers of all ages. This metaplasia varied from a few chondroblasts and chondrocytes to mature chondrocytes with mineralization. Bone formation was seen in eight dogs. These changes appeared in close approximation to the cardiac conduction system above the bundle of His. No degenerative changes were seen in the AV bundle. Approximately one-half of the large breed dogs five years of age and older had thickened medial and intima proliferation in the small coronary arterioles supplying the AV node. The results of this study suggest that the presence of cartilage and bone in the central fibrous body is a normal occurrence in large breed dogs at all ages.  相似文献   

18.
新生隐球菌格鲁比变种国内菌株的多位点微卫星灶分型   总被引:1,自引:0,他引:1  
目的 应用多位点微卫星灶分型(MLMT)对国内6个城市分离出的新生隐球菌格鲁比变种(Cryptococcus neoformans var.grubii)进行基因分型,了解该变种的国内基因型分布特征。方法 提取已鉴定的43株新生隐球菌格鲁比变种DNA,用PCR 对3个微卫星位点(CNG1, CNG2, CNG3)的基因片段进行扩增后测序.再计算每一菌株位点基序重复数(CNG1对应TA重复,CNG2对应GA重复,CNG3对应CAT重复);据基序重复数判定各菌株的基因型。结果 所有43株菌中,MLMT-17型占83.72%, 该型在临床和环境的菌株中分别占86.67%, 70%。MLMT-39,-40是新发现的基因型。结论 在我国,MLMT-17是最常见的新生隐球菌格鲁比变种基因型,普遍存在于临床和环境菌株中。表明国内临床新生隐球菌病的感染菌株主要源于本土环境菌株。  相似文献   

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Under controlled light-dark cycle (LD 12:12) and two hydratory conditions, mongrel dogs display marked day-night variations in urine flow and in its constituents. Diurnal peaks were found in urine flow and sodium excretion, while nocturnal peaks were observed in osmolality and potassium excretion. Diuretic responses, after fluid intake, were consistently faster and higher during the day than during the night. Nocturnal increases were found in plasma antidiuretic hormone (ADH), in aldosterone and in plasma renin activity (PRA), which could partially explain the present results. In all dogs there was a decrease in ADH level in the early morning hours which could account for the increased urine flow and decreased osmolality observed at this time. Plasma cortisol did not show significant temporal variations throughout the 24-hour period. Kidney denervation did not alter the day-night variations in urinary flow, sodium and osmolality, but affected the pattern of potassium excretion. A neural control of potassium excretion pattern, probably mediated by PRA-aldosterone is tentatively postulated.  相似文献   

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