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21.
This paper presents a simple method of carrying deeply located recipient vascular structures to the surface in order to facilitate end-to-side anastomoses in free-flap transplantations.  相似文献   
22.
23.
The adverse effect of seafood consumption on human health is related to the bioaccessibility in contrast with the total heavy metal level in the tissues. In this study, bioaccessibility of Cd, Cr, Cu, Mn, Ni, Pb, and Zn in Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) edible soft tissues collected along the southern Black Sea coast were investigated using in vitro digestion model. Total Pb concentration in the tissues was found to be higher than the maximum permissible limits set by European Commission. The bioaccessibility of metals in the tissues was found to be decreased in the order: Ni (83.11%) > Cu (80.47%) > Zn (76.86%) > Cd (73.32%) > Mn (69.11%) > Pb (61.07%) > Cr (58.44%). While significant positive linear regression was observed between total and bioaccessible concentrations for Mn, Pb, and Ni, significant negative linear regression was found for Cd (p < .05). The hazard quotients (HQ) calculated using bioaccessible amount were detected lower than the limit (HQ <1), which may not pose a potential hazard to humans reported by US Environmental Protection Agency. In sum, mussel consumption from sampling sites may cause a potential risk concerning human health especially for Cd and Pb in case of increased portion sizes.  相似文献   
24.
Survivors of pediatric Hodgkin's lymphoma are at risk for radiation therapy-induced second malignant neoplasms (SMNs). We identified two variants at chromosome 6q21 associated with SMNs in survivors of Hodgkin's lymphoma treated with radiation therapy as children but not as adults. The variants comprise a risk locus associated with decreased basal expression of PRDM1 (encoding PR domain containing 1, with ZNF domain) and impaired induction of the PRDM1 protein after radiation exposure. These data suggest a new gene-exposure interaction that may implicate PRDM1 in the etiology of radiation therapy-induced SMNs.  相似文献   
25.

Introduction

HLA-B*51 and HLA-B*52 are two close human leukocyte antigen (HLA) allele groups with minor amino acid differences. However, they are associated with two different vasculitides (HLA-B*51 in Behçet's disease and HLA-B*52 in Takayasu's arteritis (TAK)) and with major clinical and immunological differences. In this study, we aimed to screen a large cohort of TAK patients from Turkey for the presence of HLA-B*51 and HLA-B*52 as susceptibility and severity factors.

Methods

TAK patients (n = 330) followed at a total of 15 centers were included in the study. The mean age of the patients was 37.8 years, and 86% were women. DNA samples from the patients and healthy controls (HC; n = 210) were isolated, and the presence of HLA-B*51 or HLA-B*52 was screened for by using PCR with sequence-specific primers.

Results

We found a significant association of HLA-B*52 with TAK (20.9% vs HC = 6.7%, P = 0.000, OR = 3.7, 95% CI = 2.02 to 6.77). The distribution of HLA-B*51 did not differ between TAK patients and HCs (22.7% vs 24.8%, OR = 0.9, 95% CI = 0.60 to 1.34). The presence of HLA-B*52 decreased in late-onset patients (> 40 years of age; 12.0%, P = 0.024, OR = 0.43, 95% CI = 0.20 to 0.91). Patients with angiographic type I disease with limited aortic involvement also had a lower presence of HLA-B*52 compared to those with all other disease subtypes (13.1% vs 26%, P = 0.005, OR = 0.43, 95% CI = 0.23 to 0.78).

Conclusions

In this study, the previously reported association of TAK with HLA-B*52 in other populations was confirmed in patients from Turkey. The functional relevance of HLA-B*52 in TAK pathogenesis needs to be explored further.  相似文献   
26.
Coral Reefs - A correction to this paper has been published: https://doi.org/10.1007/s00338-021-02120-y  相似文献   
27.
The aim of this study was to determine the effects of raffinose and hypotaurine on sperm parameters after the freeze–thawing of Merino ram sperm. Totally 40 ejaculates of five Merino ram were used in the study. Semen samples, which were diluted with a Tris-based extender containing 10 mM raffinose, 5 mM hypotaurine, 5 mM raffinose +2.5 mM hypotaurine (H + R) and no antioxidant (control), were cooled to 5 °C and frozen in 0.25 ml French straws and stored in liquid nitrogen. Frozen straws were then thawed individually at 37 °C for 25 s in a water bath for evaluation.  相似文献   
28.
This study has identified horizontally acquired genomic regions of enterohaemorrhagic Escherichia coli O157:H7 that regulate expression of the type III secretion (T3S) system encoded by the locus of enterocyte effacement (LEE). Deletion of O-island 51, a 14.93 kb cryptic prophage (CP-933C), resulted in a reduction in LEE expression and T3S. The deletion also had a reduced capacity to attach to epithelial cells and significantly reduced E. coli O157 excretion levels from sheep. Further characterization of O-island 51 identified a novel positive regulator of the LEE, encoded by ecs1581 in the E. coli O157:H7 strain Sakai genome and present but not annotated in the E. coli strain EDL933 sequence. Functionally important residues of ECs1581 were identified based on phenotypic variants present in sequenced E. coli strains and the regulator was termed RgdR based on a motif demonstrated to be important for stimulation of gene expression. While RgdR activated expression from the LEE1 promoter in the presence or absence of the LEE-encoded regulator (Ler), RgdR stimulation of T3S required ler and Ler autoregulation. RgdR also controlled the expression of other phenotypes, including motility, indicating that this new family of regulators may have a more global role in E. coli gene expression.  相似文献   
29.
Effects of nicotine, and nicotine + vitamin E on glucose 6-phosphate dehydrogenase (G-6PD) activity in rat muscle, heart, lungs, testicle, kidney, stomach, brain and liver were investigated in vivo and in vitro on partially purified homogenates. Supplementation period was 3 weeks (n = 8 rats per group): nicotine [0.5 mg/kg/day, intraperitoneal (ip)]; nicotine + vitamin E [75 mg/kg/day, intragastric (ig)]; and control group (receiving only vehicle). The results showed that nicotine (0.5 mg/kg, ip) inhibited G-6PD activity in the lungs, testicle, kidney, stomach and brain by 12.5% (p < 0.001), 48% (p < 0.001), 20.8% (p < 0.001), 13% (p < 0.001) and 23.35% (p < 0.001) respectively, and nicotine had no effects on the muscle, heart and liver G6PD activity. Also, nicotine + vitamin E inhibited G-6PD activity in the testicle, brain, and liver by 32.5% (p < 0.001), 21.5% (p < 0.001), and 16.5% (p < 0.001) respectively, and nicotine + vitamin E activated the muscle, and stomach G-6PD activity by 36% (p < 0.05), and 20% (p < 0.001) respectively. In addition, nicotine + vitamin E did not have any effects on the heart, lungs, and kidney G-6PD activity. In addition, in vitro studies were also carried out to elucidate the effects of nicotine and vitamin E on G-6PD activity, which correlated well with in vivo experimental results in lungs, testicles, kidney, stomach, brain and liver tissues. These results show that vitamin E administration generally restores the inactivation of G-6PD activity due to nicotine administration in various rat tissues in vivo, and also in vitro.  相似文献   
30.
Phospholipase C zeta, a novel sperm-specific protein which is widely known to induce oocyte activation following fertilization, had already been characterized in various mammalian species, but not in water buffaloes thus far. The present study was conducted to initially characterize and compare the sequences of PLCZ1 gene of swamp and riverine buffaloes. Semen samples were collected; total RNA was extracted and reverse-transcribed. PLCZ1 cDNA was then amplified, and submitted for sequencing. Buffalo PLCZ1 gene yielded a sequence of 1905 base pair nucleotides translated into 634?bp amino acids. In general, the buffalo PLCZ1 gene was found to have high sequence identity with cattle and other domestic species. Similarly, significant residues and motifs in PLCZ1 gene sequence are found conserved in water buffaloes. However, there are variations in sequences identified between types of water buffaloes that may play a role in species-specific differences in terms of gene and protein expression, physiological mechanisms, and biological functions. The molecular information on buffalo PLCZ1 gene is highly valuable in subsequent works such as correlation studies on the identified gene variations with semen quality and fertility, and the development of biomarkers for bull fertility.  相似文献   
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