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71.
Donor specific antibodies (DSA) play a significant role in graft rejection. Many laboratory methods, varied in sensitivity and specificity, are used to detect them. We report a case of a 38-year-old man presented with end stage renal disease considered for kidney transplantation. He had no history of blood transfusions nor transplantation procedures. Dilemma rose when he got multiple positive crossmatches with matching donors and a positive autologous crossmatch due to IgG anti HLA auto-antibodies, which are at the same time against matched donors. Since positive crossmatch is a contraindication for transplant, we couldn’t perform transplant from any matched donor. Therefore, we considered a total mismatched donor then transplantation was performed. Observation after surgery showed normalization of creatinine, blood pressure and a good function of the planted allograft for two years of follow up.  相似文献   
72.
Neurons in the cerebellar cortex of camels were studied using modified Golgi impregnation methods. Neurons were classified according to their position, morphology of their soma, density and distribution of dendrites, and the course of their axons. Accordingly, eight types of neurons were identified. Three types were found in the molecular layer: upper and lower stellate cells and basket cells, and four types were found in the granular layer: granule cells, Golgi Type II cells, Lugaro cells, and unipolar brush cells. Only the somata of Purkinje cells were found in the Purkinje cell layer. The molecular layer is characterized by the presence of more dendrites, dendritic spines, and transverse fibers. Golgi cells also show extensive dendritic branching and spines. The results illustrate the neuronal features of the camel cerebellum as a large mammal living in harsh environmental conditions. These findings should contribute to advancing our understanding of species-comparative anatomy in achieving better coordination of motor activity.  相似文献   
73.
BACKGROUND: The objective of this study was to determine the incidence of undiagnosed thrombophilic factors and its relation to IVF and embryo transfer failure in women who have had three or more previous IVF-embryo transfer cycles. METHODS: The study group comprised of 90 consecutive women with three or more previously failed IVF-embryo transfer cycles (group A). Two control groups were enrolled: group B (n=90) included women who have had successful pregnancy after their first IVF-embryo transfer cycle, and group C (n=100) included women who conceived spontaneously with at least one uneventful pregnancy and no previous history of miscarriage. All women were tested for the presence of inherited [factor V Leiden (FVL) mutation, prothrombin mutation, methylenetetrahydrofolate reductase (MTHFR) mutation and deficiencies in proteins S and C and antithrombin III] or acquired (lupus anticoagulant and anticardiolipin) thrombophilic factors. RESULTS: An increase in the incidences of FVL, MTHFR and antiphospholipid antibodies was found in the study group compared with the two control groups. At least one inherited or acquired thrombophilic factor was detected in 68.9% of women with repeated IVF failure compared with 25.6 and 25% in the groups B and C, respectively (P<0.01). Combined thrombophilia (two or more thrombophilic factors) was significantly higher in women who have had repeated IVF failure as compared with the two control groups (35.6 versus 4.4 and 3%) (P<0.0001). CONCLUSION: Thrombophilia has a significant role in IVF-embryo transfer implantation failure. Women with repeated IVF-embryo transfer failure should be screened for thrombophilia.  相似文献   
74.
75.
Jordan is a country with intermediate endemicity for hepatitis B virus (HBV) infection where risk factors for viral transmission and their relative contributions are not well known. A case–control study of 100 hepatitis B virus seropositive patients and another 100 seronegative controls was conducted. Univariate analysis and logistic regression model were performed to examine probable risk factors for acquisition of hepatitis B virus infections. Logistic‐regression analysis showed that significant risk factors for acquisition of hepatitis B virus infection were sharing toothbrushes (odds ratio = 10.167; 95% confidence interval, 1.181–87.509), unhygienic dental care (odds ratio = 2.455; 95% confidence interval, 1.294–4.658), and living abroad for at least 1 year (odds ratio = 20.018; 95% confidence interval, 2.268–176.685). The presence of these risk factors emphasizes the need for both increasing the use of hepatitis B vaccines and risk‐targeted public health education. Development and enforcement of appropriate infection control guidelines for dental care services are also necessary to curtail HBV transmission. Further research that controls for confounding factors is needed to assess the relative contribution of the identified risk factors in the Jordanian community. J. Med. Virol. 82:220–223, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
76.

Purpose

To compare proteomic profiles of spermatozoa from patients with varicocele and poor sperm quality before and after varicocelectomy.

Methods

This work was designed as a prospective and observational study. The study was based on 20 men with varicocele grade 3 and poor sperm quality undergoing varicocelectomy at the Fertility Unit of Royan institute in 2009. Two semen samples were collected, one before varicocelectomy and the other after surgery. Protein separation was done by two-dimensional protein electrophoresis, and analyzed by gel densitometry and mass spectrometry. Differential sperm protein expression levels were measured by gel densitometry.

Results

Comparison of the sperm parameters showed that sperm motility and concentration were increased after varicocelectomy. At the level of protein, a total of 3 protein spots were identified whose expression was significantly lower in sperm samples before varicocelectomy compared with after surgery including heat shock protein A5 (HSPA5), superoxide dismutase 1 (SOD1) and δ-subunit of the catalytic core of mitochondrial adenosine triphosphate synthase (ATP5D).

Conclusions

High grade varicocoele affects sperm protein expression presumably because of increasing testicular temperature. These proteins play essential roles in sperm production, DNA integrity protection, and sperm motility. This novel study demonstrates that varicocelectomy can improve both sperm quality and proteins expression.  相似文献   
77.
78.
Insidious brain microinjury from motor vehicle‐induced whole‐body vibration (WBV) has not yet been investigated. For a long time we have believed that WBV would cause cumulative brain microinjury and impair cerebral function, which suggests an important risk factor for motor vehicle accidents and secondary cerebral vascular diseases. Fifty‐six Sprague‐Dawley rats were divided into seven groups (n = 8): 1) 2‐week normal control group, 2) 2‐week sham control group (restrained in the tube without vibration), 3) 2‐week vibration group (exposed to whole‐body vibration at 30 Hz and 0.5g acceleration for 4 hr/day, 5 days/week, for 2 weeks), 4) 4‐week sham control group, 5) 4‐week vibration group, 6) 8‐week sham control group, and 7) 8‐week vibration group. At the end point, all rats were evaluated in behavior, physiological, and brain histopathological studies. The cerebral injury from WBV is a cumulative process starting with vasospasm squeezing of the endothelial cells, followed by constriction of the cerebral arteries. After the 4‐week vibration, brain neuron apoptosis started. After the 8‐week vibration, vacuoles increased further in the brain arteries. Brain capillary walls thickened, mean neuron size was obviously reduced, neuron necrosis became prominent, and wide‐ranging chronic cerebral edema was seen. These pathological findings are strongly correlated with neural functional impairments. © 2014 Wiley Periodicals, Inc.  相似文献   
79.
IntroductionWe investigated the effect angiotensin II (Ang II), a corpus cavernosal smooth muscle (CCSM) constrictor peptide, has on tissue taken from rabbits following chronic partial bladder outlet obstruction (PBOO), as this model is characterized by an increase in corpus cavernosal collagen deposition and a marked reduction and impaired relaxation of CCSM cells.AimTo determine the interaction between Ang II and nitric oxide (NO) and the development of oxidative stress (OS) in a rabbit model of chronic PBOO.MethodsCorpus cavernosal tissue was obtained from 12 sham‐operated and 20 PBOO rabbits. Organ bath studies determined Ang II/NO interaction on CCSM function using losartan (AT1 receptor antagonist), sodium nitroprusside (SNP, NO donor), electrical field stimulation (EFS), and vardenafil (phosphodiesterase type 5 inhibitor). The role of OS in the Ang II response was also determined using diphenylene iodonium chloride (DPI), the nicotinamide adenine dinucleotide phosphate oxidase inhibitor, which inhibits superoxide production and superoxide dismutase (SOD, the enzyme that accelerates the breakdown of superoxide).Main Outcome MeasureAction of Ang II and AT1 receptor antagonist, as well as SOD and DPI on CCSM function.ResultsAng II caused a dose‐dependent contraction of CCSM strips that was enhanced in PBOO rabbits and inhibited by losartan, DPI, and SOD. CCSM relaxation induced by SNP/EFS was impaired in this model and improved by vardenafil and losartan.ConclusionsThese findings imply that the increased Ang II contractile response is a pathological consequence of PBOO and that AT1 receptor inhibition may be a therapeutic approach to treat ED associated with PBOO.  相似文献   
80.

Introduction

The aim of the study was to assess cyclic fatigue resistance of reciprocating (Reciproc and WaveOne) and continuous rotating (ProTaper) nickel-titanium files after immersion in different irrigation solutions with or without surfactants during several short time periods.

Methods

A total of 270 new Reciproc R25, WaveOne Primary, and ProTaper F2 files were tested. Instruments of each brand were divided into 1 control group (n = 10) formed by new files and 4 test groups (n = 20) formed by instruments dynamically immersed at 37°C for 16 mm in 5.25% sodium hypochlorite (NaOCl), Hypoclean (5.25% NaOCl with surfactant), 17% EDTA, or EDTA Plus (17% EDTA with surfactant). Each test group was subdivided into 2 subgroups (n = 10) on the basis of the time of dynamic immersion in the endodontic irrigant solution (45 seconds or 3 minutes). Resistance to cyclic fatigue was determined by recording time to fracture in a stainless steel artificial canal with a 60° angle of curvature and 5-mm radius of curvature. The fracture surface was examined by using scanning electron microscopy.

Results

Immersion in NaOCl did not reduce the cyclic fatigue of reciprocating or continuous nickel-titanium files. The 17% EDTA reduced the fatigue resistance of all instruments after 3 minutes. The immersion in irrigants with surfactants did not influence the cyclic fatigue of instruments except for Reciproc immersed in Hypoclean solution.

Conclusions

EDTA immersion reduced the cyclic fatigue resistance of all instruments after 3 minutes. Addition of surfactants did not influence the cyclic fatigue of files except when added to NaOCl when it contacts Reciproc instruments.  相似文献   
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