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991.
Huiping Zhang Fatih Ozbay Jaakko Lappalainen Henry R Kranzler Christopher H van Dyck Dennis S Charney Lawrence H Price Steven Southwick Bao-Zhu Yang Ann Rasmussen Joel Gelernter 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(4):387-393
Genetic variation at the locus encoding the brain derived neurotrophic factor (BDNF) has been implicated in some neuropsychiatric disorders such as Alzheimer's disease (AD), affective disorders (AFDs), schizophrenia, and substance dependence. We therefore performed a mutation scan of the BDNF gene to identify novel gene variants and examined the association between BDNF variants and several neuropsychiatric phenotypes in European American (EA) subjects and controls. Using denaturing high performance liquid chromatography (dHPLC), we identified a novel variant (G-712A) in the putative promoter region. This variant and two previously reported BDNF SNPs (C270T and Val66Met) were genotyped in 295 patients with AD, 108 with AFDs, 96 with posttraumatic stress disorder (PTSD), 84 with schizophrenia, 327 with alcohol and/or drug dependence, and 250 normal control subjects. No association was found between these three BDNF gene variants and AD, AFDs, PTSD, or schizophrenia. However, there was a nominally higher frequency of the G-712A G-allele and the G/G genotype in subjects with substance dependence than in controls (Allele: chi(2) = 4.080, df = 1, P = 0.043; Genotype: chi(2) = 7.225, df = 2, P = 0.027). Although after correction for multiple testing, the findings are not considered significant (threshold P-value was set at 0.020 by the program SNPSpD), logistic regression analyses confirmed the modest association between SNP G-712A and substance dependence, when the sex and age of subjects were taken into consideration. The negative results for AFDs, PTSD, and schizophrenia could be due to the low statistical power. Further study with larger samples is warranted. 相似文献
992.
A porcine model was established to test the mucosal toxicity potential of a thiophene thiourea (PHI-443)-based anti-HIV microbicide and a vanadocene-based spermicide, vanadocene dithiocarbamate (VDDTC) in comparison to benzalkonium chloride (BZK). Nine domestic pigs (Duroc) in nonestrus stage received a single intravaginal application of 2% BZK, 2% PHI-443, or 0.1% VDDTC-containing gel. At various times after gel application, cell differentials and levels of inflammatory cytokines (IL-1beta, IL-4, IL-6, IL-8, IL-10, IL-18, IFN-gamma, and TNF-alpha) in cervicovaginal lavage (CVL) fluid were monitored by flow cytometry and ELISA, respectively. Eight pigs were exposed intravaginally to a gel with and without BZK or VDDTC for 4 consecutive days and vaginal tissues were scored histologically for inflammation using a new scoring system. Only CVL fluid from pigs exposed to BZK showed a significant increase of IL-1beta, IL-8, and also IL-18 production when compared to the controls, PHI-443 or VDDTC-treated groups. Maximum levels of BZK-induced IL-1beta (100-fold), IL-8 (2,500-fold), IL-18 (80-fold), and IFN-gamma (10-fold) were found at 24 hours. In the in vivo porcine vaginal irritation model, increased levels of vaginal IL-1beta, IL-8, and IL-18 were associated with histological changes consistent with vaginal inflammation. These results demonstrate that key cervicovaginal inflammatory cytokines are useful in vivo biomarkers for predicting the mucosal toxicity potential of vaginal products in the physiologically relevant and sensitive porcine model. 相似文献
993.
Mustafa Gerek Bülent Satar Fatih Yazar Hasan Ozan Yal?in Ozkaptan 《Otology & neurotology》2004,25(6):973-976
OBJECTIVE: To investigate the utility of a newly described approach, the transcanal anterior approach that is a modification of the subcochlear approach for the drainage of cystic lesions of the petrous apex. STUDY DESIGN: Prospective temporal bone study. SETTING: Tertiary referral center. MATERIALS: A total of six cadaveric temporal bone specimens (four males) were included. Right ear in four specimens and left ear in two specimens were used. INTERVENTIONS: The approach commenced with postauricular skin incision. After the transsection of the meatal skin, antero-inferior tympanotomy was performed. Anteroinferior canaloplasty localized the carotid canal. As much as 0.5 cm of the vertical segment of the internal carotid artery was skeletonized. After the identification of the artery, petrous apex cells were reached by drilling the cortical bone between the cochlea and the internal carotid artery. An air cell tract was established. Position and length of the tract in two specimens were demonstrated on the 1 mm-cut computerized tomography scans. MAIN OUTCOME MEASURES: Utility of the approach was investigated based on the established criteria: anteroposterior diameter and height of the fenestra of the tract, length of the tract from the cochlea to the deepest point of the tract (depth of the tract), and the injury risk of the internal carotid artery and the cochlea. RESULTS: The mean anteroposterior diameter, the height, and the length were 4.7 +/- 1.05 mm, 3.2 +/- 0.68 mm, and 14.7 +/- 1.1 mm, respectively. Injury did not occur in the cochlea or internal carotid artery in any of the specimens. CONCLUSION: With the subcochlear approach, there is always potential risk of injury to the cochlea, the internal carotid artery, and the jugular bulb. Although this new approach includes a technically challenging stage (exposing the vertical portion of the internal carotid artery), partly exposing the vertical portion of the artery provides a safer approach, which decreases the injury risk for the round window and the jugular bulb. Additionally, measurements show that it is possible to reach a considerable part of the petrous apex cells. 相似文献
994.
995.
Fatih Güzelbulut Pnar Gken Güray Can Gupse Adal Aya Gken Deirmenci Saltürk Ekrem Aslan Kamil
zdil Hamdi Levent Doanay 《The Turkish journal of gastroenterology》2021,32(4):412
BackgroundIt is controversial whether entecavir or tenofovir differs in reducing hepatocellular carcinoma (HCC) risk. We aimed to compare the efficacy of entecavir and tenofovir in reducing HCC risk in chronic hepatitis B (CHB) patients. MethodsThis retrospective study included 607 nucleos(t)ide naive CHB patients who had received entecavir or tenofovir. Patients who developed HCC during the first 12 months of therapy were excluded. Cumulative HCC incidences at years 2, 3, 4, 5 and 10 were compared between entecavir and tenofovir groups. Factors associated with HCC were determined by univariate and multivariate analyses.ResultsNineteen (3.1%) patients developed HCC, 12 (4.8%) in entecavir group and 7 (1.9%) in tenofovir group (P = .045). In the entire cohort, cumulative HCC incidences at years 2, 3, 4, 5 and 10 were 1.8%, 2.9%, 4.4%, 5.2% and 9.9% in entecavir group, and 0.6%, 2.4%, 2.4%, 2.4% and 3.7% in tenofovir group, respectively (log-rank P = .130). In multivariate analysis, age ≥50 years, cirrhosis, decompensated cirrhosis, high GGT and low platelet levels were associated with HCC in the entire cohort. In advanced fibrosis/cirrhosis cohort, cumulative HCC incidences at years 2, 3, 4, 5 and 10 were 4.6%, 7.1%, 8.6%, 12.1% and 15.5% in entecavir group, and 1.8%, 5.6%, 5.6%, 5.6% and 8.5% in tenofovir group, respectively (log-rank P = .267). In multivariate analysis, age ≥50 years, decompensated cirrhosis, high GGT and low platelet levels were associated with HCC in the advanced fibrosis/cirrhosis cohort.ConclusionEntecavir and tenofovir are similarly effective in reducing HCC risk in CHB patients. 相似文献
996.
Jannis Thien Jascha Bahlmann Andreas Alexander Kevin Ruwisch Jari Rodewald Tobias Pohlmann Martin Hoppe Fatih Alarslan Martin Steinhart Baki Altuncevahir Padraic Shafer Carola Meyer Florian Bertram Joachim Wollschlger Karsten Küpper 《Materials》2022,15(1)
Here, we present the (element-specific) magnetic properties and cation ordering for ultrathin Co-rich cobalt ferrite films. Two Co-rich films with different stoichiometry ( and ) have been formed by reactive solid phase epitaxy due to post-deposition annealing from epitaxial CoO/FeO bilayers deposited before on Nb-doped SrTiO(001). The electronic structure, stoichiometry and homogeneity of the cation distribution of the resulting cobalt ferrite films were verified by angle-resolved hard X-ray photoelectron spectroscopy. From X-ray magnetic circular dichroism measurements, the occupancies of the different sublattices were determined using charge-transfer multiplet calculations. For both ferrite films, a partially inverse spinel structure is found with increased amount of cations in the low-spin state on octahedral sites for the film. These findings concur with the results obtained by superconducting quantum interference device measurements. Further, the latter measurements revealed the presence of an additional soft magnetic phase probably due to cobalt ferrite islands emerging from the surface, as suggested by atomic force microscope measurements. 相似文献
997.
Ozgur Acikgoz Burcin Cakan Tarik Demir Ahmet Bilici Bala Basak Oven Jamshid Hamdard Oktay Olmuscelik Omer Fatih Olmez Mesut Seker Ozcan Yildiz 《Medicine》2021,100(44)
The aim of this study was to investigate the predictive and prognostic value of PLR, and the relationship between PLR and tumor localization.A total of 229 patients with de-novo metastatic CRC were retrospectively analyzed. The cutoff value for PLR was defined by the receiver operating characteristic (ROC) curve analysis and threshold value of 196.5 as best cut-off value was found.The higher rate of BRAF mutation was significantly detected for patients with PLRhigh (> 196.5) compared to those with PLRlow (≤196.5) (P = .001). PLR was significantly higher in tumors located on the right colon (P = .012). PLR, tumor localization, the presence of surgery for primary tumor, the presence of curative surgery, the presence of metastasectomy for progression-free survival (PFS) and PLR, gender, BRAF mutation, tumor localization, the presence of surgery for primary tumor, the presence of metastasectomy for overall survival (OS) were found to be prognostic factors by univariate analysis. Multivariate analysis showed that PLR, the presence of curative surgery and the presence of metastasectomy for both PFS and OS were found to be independent prognostic factors. Moreover, a logistic regression analysis indicated that PLR and tumor localization were found to be an independent factors for predicting response to systemic treatment (P < .001 and P = .023 respectively).Our results showed that pretreatment PLR was readily feasible and simple biomarker predicting response to treatment and survival, in addition it was significantly associated with tumor localization. 相似文献
998.
999.
Numanoglu V Ermis B Dursun A Battal F Ornek Z Dogan SM Ugur B 《Clinical dysmorphology》2007,16(4):269-270
Supernumerary nostril is an extremely rare congenital anomaly. It can be unilateral or bilateral and it sometimes occurs in association with other congenital abnormalities. We describe a newborn infant with bilateral supernumerary nostrils together with oesophageal atresia and patent ductus arteriosus, an association that has not been reported previously in the literature. 相似文献
1000.
Asist. Prof. Temel Fatih Yilmaz Mehmet Ali Gultekin Hac Mehmet Turk Mehmet Besiroglu Dilek Hacer Cesme Melih Simsek Alpay Alkan Huseyin Toprak 《Radiology and oncology》2022,56(1):54
BackgroundWe aimed to investigate whether there is a difference between intrahepatic cholangiocarcinoma (IHCC) and liver metastases of gastrointestinal system (GIS) adenocarcinoma in terms of apparent diffusion coefficient (ADC) values.Patients and methodsFrom January 2018 to January 2020, we retrospectively examined 64 consecutive patients with liver metastases due to gastrointestinal system adenocarcinomas and 13 consecutive IHCC in our hospital’s medical records. After exclusions, fifty-three patients with 53 liver metastases and 10 IHCC were included in our study. We divided the patients into two groups as IHCC and liver metastases of GIS adenocarcinoma. For mean apparent diffusion coefficient (ADCmean) values, the region of interests (ROI) was placed in solid portions of the lesions. ADCmean values of groups were compared.ResultsThe mean age of IHCC group was 62.50 ± 13.49 and mean age of metastases group was 61.15 ± 9.18. ADCmean values were significantly higher in the IHCC group compared to the metastatic group (p < 0.001). ROC curves method showed high diagnostic accuracy (AUC = 0.879) with cut-off value of < 1178 x 10-6 mm2/s for ADCmean (Sensitivity = 90.57, Specificity = 70.0, positive predictive value [PPV] = 94.1, negative predictive value [NPV] = 58.3) in differentiating adenocarcinoma metastases from IHCC.ConclusionsThe present study results suggest that ADC values have a potential role for differentiation between IHCC and GIS adenocarcinoma liver metastases which may be valuable for patient management.Key words: cholangiocarcinoma, gatrointestinal system, liver metastases, apparent diffusion coefficient, diffusion weighted image, MRI 相似文献