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991.
Ismail Hakki Ersoy E. Guçhan Alanoglu Banu Kale Koroglu Simge Varol Selahaddin Akcay Yunus Ugan Sıddıka Ersoy Mehmet Numan Tamer 《Biological trace element research》2010,138(1-3):22-27
Although so many studies exist on effect of fluoride on hematological parameters in experimental animals, a few studies have been conducted to investigate the effects of chronic fluorosis on hematological parameters in humans’ subjects with endemic fluorosis. So we aimed to determine the hematological parameters in patients with endemic fluorosis. The study group consisted of 60 patients with endemic fluorosis (27 females, 33 males, and mean age 33.4?±?9.6 years). An age-, gender-, and body mass index-matched control group was composed of 34 healthy volunteers (11 females, 23 males with a mean age 32.6?±?5.6 years). Urine fluoride levels of fluorosis patients were significantly higher than control subjects as expected (0.42?±?0.09 vs 1.92?±?0.14 mg/l, respectively; P?<?0.001). There were no statistically significant differences between the fluorosis group and control group with respect to hematological parameters (complete blood count and ferritin). We concluded that chronic fluorosis has no effect on hematological parameters in patients with endemic fluorosis. 相似文献
992.
Malaria is endemic in the Cukurova region while it is sporadic in other regions of Turkey. Therefore, the laboratory and clinical diagnosis of malaria is important for the treatment of malaria. In this study, 92 blood samples that were taken from the suspected malaria patients for routine diagnosis in a period of 10 years between 1999 and 2009 were analyzed. All of these blood samples were examined by microscopic examinations using Giemsa-stained thick blood films, nested PCR, and real-time PCR. The sensitivity-specificity and positive-negative predictive values for these diagnostic tests were then calculated. It was found that the positive predictive values of microscopic examination of thick blood films, nested PCR, and real-time PCR were 47.8%, 56.5%, and 60.9% for malaria, respectively. The real-time PCR was found to have a specificity of 75% and sensitivity of 100%, while specificity and sensitivity of nested PCR was found 81.2% and 97.7% according to the microscopic examination of thick blood films, respectively. 相似文献
993.
Yun Li Barbara Pawlik Nursel Elcioglu Mona Aglan Gökhan Yigit Ferda Percin Gudrun Nürnberg Asim Cenani Boi-Dinh Chung Samira Ismail Ayca D. Aslanger Christian Netzer Pete Scambler Hanan Hamamy Raoul Hennekam Peter Nürnberg Joachim Herz Bernd Wollnik 《American journal of human genetics》2010,86(5):696-40630
994.
M. A. Latif Mohd. Yosuh Omar Soon Guan Tan Siti Shapor Siraj Abdul Rahim Ismail 《Biochemical genetics》2010,48(3-4):266-286
Studies on hybridization, inheritance, and population genetics of brown planthoppers that infest rice and weeds were undertaken using starch gel electrophoresis to determine whether the weed-infesting population represents a biological race or a species. F1 and F2 generations were produced by crosses between parental insects from the two populations with little indication of hybrid sterility. Gpi, Mdh, and Idh loci were inherited in a simple Mendelian fashion in families of two sympatric populations. Sixteen populations of Nilaparvata spp. from eight locations were collected. The Mdh, Idh, Pgm, Gpi, 6Pgd, and Acp loci were polymorphic. The N. lugens of rice with high esterase activity were clustered into a group and characterized by the presence of alleles Gpi 110 and Gpi 120 , whereas N. lugens from weeds with low esterase activity were clustered into another group and characterized by Gpi 100 and Gpi 90 . There was a lack of heterozygotes between the common alleles of the two populations. This means that the two groups of individuals belong to different gene pools. 相似文献
995.
Mi X Eskridge K Wang D Baenziger PS Campbell BT Gill KS Dweikat I Bovaird J 《Statistical applications in genetics and molecular biology》2010,9(1):Article38
Quantitative trait loci (QTL) mapping often results in data on a number of traits that have well-established causal relationships. Many multi-trait QTL mapping methods that account for the correlation among multiple traits have been developed to improve the statistical power and the precision of QTL parameter estimation. However, none of these methods are capable of incorporating the causal structure among the traits. Consequently, genetic functions of the QTL may not be fully understood. Structural equation modeling (SEM) allows researchers to explicitly characterize the causal structure among the variables and to decompose effects into direct, indirect, and total effects. In this paper, we developed a multi-trait SEM method of QTL mapping that takes into account the causal relationships among traits related to grain yield. Performance of the proposed method is evaluated by simulation study and applied to data from a wheat experiment. Compared with single trait analysis and the multi-trait least-squares analysis, our multi-trait SEM improves statistical power of QTL detection and provides important insight into how QTLs regulate traits by investigating the direct, indirect, and total QTL effects. The approach also helps build biological models that more realistically reflect the complex relationships among QTL and traits and is more precise and efficient in QTL mapping than single trait analysis. 相似文献
996.
The 1990s were a period of considerable economic and social instability in Kazakhstan. The current study documents information on the growth performance of children living in Kazalinsk district in the far west of Kazakhstan over this turbulent period. Using anthropometric data of children, from random samples collected in 1992, 1994 and 2000, we investigate changes in body size of 4.0–4.9-year-old children over the 8-year-study period. Between 1992 and 2000, there was no statistically significant change in body size of 4.0–4.9-year-old boys, but 4.0–4.9-year-old girls became significantly smaller. This may have resulted from the prolonged period of economic instability in Kazakhstan. Furthermore, using detailed dietary intake data collected in 1994, evidence is presented to support a suggestion that the different responses to economic hardship, evidenced in the achieved body size of boys and girls, may have been influenced by gender-discrimination in household food allocation. 相似文献
997.
Sopi RB Martin RJ Haxhiu MA Dreshaj IA Yao Q Jafri A Zaidi SI 《American journal of physiology. Lung cellular and molecular physiology》2008,295(2):L348-L355
Prolonged hyperoxic exposure contributes to neonatal lung injury, and airway hyperreactivity is characterized by enhanced contraction and impaired relaxation of airway smooth muscle. Our previous data demonstrate that hyperoxia in rat pups upregulates expression of brain-derived neurotrophic factor (BDNF) mRNA and protein, disrupts NO-cGMP signaling, and impairs cAMP production in airway smooth muscle. We hypothesized that BDNF-tyrosine kinase B (TrkB) signaling plays a functional role in airway hyperreactivity via upregulation of cholinergic mechanisms in hyperoxia-exposed lungs. Five-day-old rat pups were exposed to >or=95% oxygen or room air for 7 days and administered daily tyrosine kinase inhibitor K-252a (50 microg x kg(-1) x day(-1) i.p.) to block BDNF-TrkB signaling or vehicle. Lungs were removed for HPLC measurement of ACh or for in vitro force measurement of lung parenchymal strips. ACh content doubled in hyperoxic compared with room air-exposed lungs. K-252a treatment of hyperoxic pups restored ACh content to room air levels. Hyperoxia increased contraction and impaired relaxation of lung strips in response to incremental electrical field stimulation. K-252a administration to hyperoxic pups reversed this increase in contraction and decrease in relaxation. K-252a or TrkB-Fc was used to block the effect of exogenous BDNF in vitro. Both K-252a and TrkB-Fc blocked the effects of exogenous BDNF. Hyperoxia decreased cAMP and cGMP levels in lung strips, and blockade of BDNF-TrkB signaling restored cAMP but not cGMP to control levels. Therefore, hyperoxia-induced increase in activity of BDNF-TrkB receptor signaling appears to play a critical role in enhancing cholinergically mediated contractile responses of lung parenchyma. 相似文献
998.
999.
Rickettsiae cause some of the most severe human infections, including epidemic typhus and Rocky Mountain spotted fever. Substantial progress has been made in research into the genomics, vector relationships, pathogenesis and immunity of these obligate, intracellular, arthropod-transmitted bacteria. This Review summarizes our understanding of the early and late events in pathogenesis and immunity, modulation of the host response to rickettsial infection by the vector, host defence, virulence mechanisms and rickettsial manipulation of host cells. 相似文献
1000.
Phosphorylation of histone protein H2AX on serine 139 (gamma-H2AX) occurs at sites flanking DNA double-stranded breaks (DSBs) and can provide a measure of the number of DSBs within a cell. We describe a flow cytometry-based method optimized to measure gamma-H2AX in nonfixed mononuclear blood cells as well as in cultured cells, which is more sensitive and involves less steps compared with protocols involving fixed cells. This method can be used to monitor induction of gamma-H2AX in mononuclear cells from cancer patients undergoing radiotherapy and for detection of gamma-H2AX throughout the cell cycle in cultured cells. The method is based on the fact that H2AX like other histone proteins are retained in the nucleus when cells are lysed at physiological salt concentrations. Cells are therefore added without fixation to a solution containing detergent to lyse the cells along with a fluorescein isothiocyanate-labeled monoclonal gamma-H2AX antibody, DNA staining dye and blocking agents. The stained nuclei can be analyzed by flow cytometry to monitor the level of gamma-H2AX to determine the level of DSBs and DNA content and to determine the cell cycle stage. The omission of fixation simplifies staining and enhances the sensitivity. This protocol can be completed within 4-6 h. 相似文献