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51.
There have been significant evolutionary pressures on the chicken during both its speciation and its subsequent domestication by man. Infectious diseases are expected to have exerted strong selective pressures during these processes. Consequently, it is likely that genes associated with disease susceptibility or resistance have been subject to some form of selection. Two genes involved in the immune response (interferon-γ and interleukin 1-β) were selected for sequencing in diverse chicken populations from Pakistan, Sri Lanka, Bangladesh, Kenya, Senegal, Burkina Faso and Botswana, as well as six outgroup samples (grey, green, red and Ceylon jungle fowl and grey francolin and bamboo partridge). Haplotype frequencies, tests of neutrality, summary statistics, coalescent simulations and phylogenetic analysis by maximum likelihood were used to determine the population genetic characteristics of the genes. Networks indicate that these chicken genes are most closely related to the red jungle fowl. Interferon-γ had lower diversity and considerable coding sequence conservation, which is consistent with its function as a key inflammatory cytokine of the immune response. In contrast, the pleiotropic cytokine interleukin 1-β had higher diversity and showed signals of balancing selection moderated by recombination, yielding high numbers of diverse alleles, possibly reflecting broader functionality and potential roles in more diseases in different environments. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. An erratum to this article can be found at  相似文献   
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It is of interest to evaluate the clinical effectiveness and safety of vildagliptin as monotherapy and combination therapy of vildagliptin and metformin for the management of type 2 diabetes mellitus (T2DM) patients in Indian settings. The study included patients with T2DM (aged >18 years) receiving vildagliptin monotherapy and vildagliptin in combination with metformin therapy of various strengths. Data related to demographics, risk factors, medical history, glycated hemoglobin (HbA1c) levels, and medical therapies were retrieved from medical records. Out of 9678 patients (median age, 52.0 years), 59.1% were men. A combination of vildagliptin and metformin (50/500 mg) was the most commonly used therapy (54.8%), and the median duration of therapy was 24.0 months. The predominant reason for selecting vildagliptin therapy was to improve HbA1c levels (87.8%). A total of 87.5% of patients required dosage up-titration. Vildagliptin therapy was used in patients with T2DM and associated complications (peripheral neuropathy, CAD, nephropathy, retinopathy, autonomous neuropathy, stroke/TIA, and peripheral artery disease). Among 5175 patients who experienced body weight changes, a majority of patients showed a loss of weight (68.6%). The target glycemic control was achieved in 95.3% of patients. The mean HbA1c levels were significantly decreased post-treatment (mean change: 1.34%; p<0.001). Adverse events were reported in 0.4% of patients. Physicians rated the majority of patients as good to excellent on the global evaluation of efficacy and tolerability scale (98.9%, each). Vildagliptin as monotherapy and combination therapy of vildagliptin and metformin was an effective therapy in reducing HbA1c helps in achieving target glycemic control, and was well tolerated in Indian patients with T2DM continuum.  相似文献   
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To elucidate the attachment mechanism of dentin and cellular cementum, developing and developed cellular cementum of rat molars was examined by light microscopy. Routine histological staining, immunohistochemical staining for bone sialoprotein (BSP) and osteopontin (OPN), and digestion tests with trypsin were conducted. Two different types of cellular cementogenesis were established, one on the mesial (type I cementogenesis) and one on the distal sides (type II cementogenesis) of the examined roots. In the type I cementogenesis a thin initial cementum layer, which was fibril-poor, hematoxylin-stained, and immunopositive for BSP and OPN, appeared on the mineralized dentin. With cellular cementogenesis, the layer became the cemento-dentinal junction. The cementum mineralization did not precede the dentin mineralization. After trypsin treatment the cemento-dentinal junction lost immunoreactivity for BSP and OPN and the cementum was detached from the dentin. In the type II cementogenesis the cellular cementum formed directly on the predentin without the initial cementum layer and the cementum mineralization preceded the dentin mineralization. Cemental and predentinal fibrils appeared to intermingle, as the cemento-dentinal junction was indiscernible by any staining. Trypsin treatment did not cause cementum detachment. The findings of the present study suggest that: (1) The type I cementogenesis requires the intervening initial cementum to bind cementum and dentin and to induce the cementum mineralization. (2) In the type II cementogenesis the cemento-dentinal attachment depends on fibril intermingling and the cementum mineralization advances apically and very rapidly, probably producing mineralization foci. (3) The formation of the initial cementum depends on the speed of the cementogenesis in the apical direction.  相似文献   
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This study was conducted to determine the frequencies of non-metric tooth crown traits of Vedda of Sri Lanka and to investigate the affinities of these morphological variations with those of other world populations.Fifty dental plaster casts were observed. The Arizona State University dental anthropology system was adopted for classification of the 16 traits observed. We used 13 traits to compare the Vedda and other world populations. Using the frequencies of 13 traits, Smith Mean Measure of Divergence was calculated to determine inter-population distances. Affinities among the Vedda and other world populations were expressed in two dimensions of the principal coordinate analysis.Cusp number in mandibular second molar and hypocone absence in maxillary second molar had the highest frequency at 95.9% and 93.8%, respectively. Shovelling, double shovelling in the maxillary central incisor and deflecting wrinkle in the mandibular first molar had the lowest frequency at 0%. The principal coordinate analysis showed that Sino American and Western Eurasian populations were separated in negative and positive directions in the first principal coordinate axis. Vedda located with the Western Eurasian population groups. Sahul and Sunda Pacific populations located in the intermediate position between Sino American and Western Eurasian populations.The dental phenotype of Vedda has close affinities with those of early south Asian populations. They are far different from Sino American and Sunda pacific populations. Vedda shows closer affinities to Sahul Pacific and South African (Bantu) populations.  相似文献   
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