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1.
In order to examine the association between alcohol dehydrogenase 3 (ADH3) genotypes and risk of head and neck squamous cell carcinomas (HNSCC), we conducted a hospital based case-control study including 348 cases and 330 controls. DNA isolated from exfoliated cells from the oral cavity were genotyped for ADH3 polymorphisms using PCR followed by SspI digestion. Odds ratios (OR) and hazards ratios (HR) were done by unconditional logistic regression and Cox regression. Relative to ADH3(2-2) carriers, ADH3(1-1) [OR, 0.7; 95% confidence interval (CI), 0.4-1.1] and ADH3(1-2) (OR, 0.8; 95% CI, 0.5-1.2) had a nonsignificant reduced risk of HNSCC. ADH(1-2) smokers of >30 pack-years were at decreased risk of oral cavity squamous cell carcinomas compared with ADH3(2-2) (OR, 0.3, 0.1-0.9), whereas ADH3(1-1) smokers were not. After adjustment, those with ADH3(1-2) had significantly worse overall survival compared with ADH3(1-1) (HR, 0.3, 0.2-0.6) or ADH3(2-2) (HR, 0.4, 0.2-0.9) and increased recurrence (ADH3(1-1), 0.2, 0.1-0.6; ADH3(2-2), 0.6, 0.2-1.3). Our data did not show that ADH3 genotypes had a significantly independent effect on the risk of HNSCC, nor did they modify the risks increased by alcohol or tobacco consumption and high-risk human papillomavirus infection. However, participants with ADH3(1-2) genotype were associated with poorer survival compared with those who had the other two ADH3 genotypes and a higher rate of recurrence than participants with ADH3(1-1) genotype.  相似文献   
2.
Primary cutaneous gamma‐delta (γδ) T‐cell lymphoma is an extremely rare and aggressive variant of cutaneous lymphoma. Central nervous system (CNS) involvement, a rare finding, and hemophagocytic syndrome are two complications that are commonly fatal. We describe a 58‐year‐old patient presenting with skin plaque who subsequently developed subcutaneous nodules diagnosed as cutaneous T‐cell lymphoma (CTCL), clinically resembling ‘mycosis fungoides’. The patient was treated with repeat topical radiation therapies but had frequent relapsed disease. Approximately 4.5 years after, the patient presented with third and sixth cranial nerve palsies and was found to have CNS involvement by lymphoma per positron emission tomography—computed tomography (PET/CT) and a biopsy of foramen magnum. Phenotypically, the tumor cells were CD3(+)/CD4(?)/CD8(?)/CD7(+)/CD5(?)/CD30(?)/TCRαβ(?)/TCRγδ(+). Despite aggressive strategies taken, the patient expired 3 months after the diagnosis of the CNS lesion. A retrospective investigation proved the original CTCL to be γδ T‐cell in origin, confirming an indolent cutaneous γδ T‐cell lymphoma with eventual CNS manifestation. We present this case to draw attention to the entity, which can occasionally present with misleading histopathologic and clinical features. In addition, we provide a review of the literature to summarize clinical and pathologic features of the reported similar cases.  相似文献   
3.
This study applied an experimental rat model and ceramic as an artificial matrix to explore the ultrastructural development of new bone production in tibia defects. By X-ray diffraction control or energy-dispersive X-ray analysis the nature of ceramic was verified and routine histology and TEM investigation were used to demonstrate bone - ceramic interaction. The results show that biphasic ceramic can promote bone growth in an osseous defect and is therefore an alternative to autogenous bone matrix. The porousity and bioactivity of the biphasic ceramic enhanced bone formation and provided a scaffold for new lamellar bone invasion.  相似文献   
4.
BACKGROUNDMuscle growth promoters are being developed for the treatment of disease-induced loss of muscle mass. Ligandrol and ostarine are selective androgen receptor modulators (SARMs) with a non-steroidal structure and a presumably more favorable side effect profile. In recent years, these substances with or without “post-cycle therapy” (PCT) are often misused by amateur athletes aiming to promote muscle growth. At the same time, reports on their toxic effects on organ systems are emerging.CASE SUMMARYWe report two cases of liver injury in young men who used ligandrol and/or ostarine for a few weeks followed by the use of substances for PCT. Acute liver injury occurred in both cases after stopping SARMs while on PCT. The clinical picture was dominated by jaundice and fatigue. The biochemical pattern showed a mixed type of injury with normal alkaline phosphatase and high concentrations of bilirubin and serum bile acids. Histological evidence showed predominantly cholestatic injury with canalicular bile plugs, ductopenia, and mild hepatocellular damage without significant fibrosis. The patients recovered from the condition after 3 mo. The off target effects of SARMs were likely idiosyncratic, but our report highlights the yet unrecognized effects of other toxic substances used for PCT, supra-therapeutic doses, and the complete absence of monitoring for adverse effects.CONCLUSIONAmong muscle-building amateur athletes, SARMs (ligandrol or ostarine) and/or substances in PCT may cause cholestatic liver injury with prolonged recovery.  相似文献   
5.
Wu YT  Wei J  Hadjiiski LM  Sahiner B  Zhou C  Ge J  Shi J  Zhang Y  Chan HP 《Medical physics》2007,34(8):3334-3344
We have developed a false positive (FP) reduction method based on analysis of bilateral mammograms for computerized mass detection systems. The mass candidates on each view were first detected by our unilateral computer-aided detection (CAD) system. For each detected object, a regional registration technique was used to define a region of interest (ROI) that is "symmetrical" to the object location on the contralateral mammogram. Texture features derived from the spatial gray level dependence matrices and morphological features were extracted from the ROI containing the detected object on a mammogram and its corresponding ROI on the contralateral mammogram. Bilateral features were then generated from corresponding pairs of unilateral features for each object. Two linear discriminant analysis (LDA) classifiers were trained from the unilateral and the bilateral feature spaces, respectively. Finally, the scores from the unilateral LDA classifier and the bilateral LDA asymmetry classifier were fused with a third LDA whose output score was used to distinguish true mass from FPs. A data set of 341 cases of bilateral two-view mammograms was used in this study, of which 276 cases with 552 bilateral pairs contained 110 malignant and 166 benign biopsy-proven masses and 65 cases with 130 bilateral pairs were normal. The mass data set was divided into two subsets for twofold cross-validation training and testing. The normal data set was used for estimation of FP rates. It was found that our bilateral CAD system achieved a case-based sensitivity of 70%, 80%, and 85% at average FP rates of 0.35, 0.75, and 0.95 FPs/image, respectively, on the test data sets with malignant masses. In comparison to the average FP rates for the unilateral CAD system of 0.58, 1.33, and 1.63, respectively, at the corresponding sensitivities, the FP rates were reduced by 40%, 44%, and 42% with the bilateral symmetry information. The improvement was statistically significance (p < 0.05) as estimated by JAFROC analysis.  相似文献   
6.
The authors have developed a semiautomatic system for segmentation of a diverse set of lesions in head and neck CT scans. The system takes as input an approximate bounding box, and uses a multistage level set to perform the final segmentation. A data set consisting of 69 lesions marked on 33 scans from 23 patients was used to evaluate the performance of the system. The contours from automatic segmentation were compared to both 2D and 3D gold standard contours manually drawn by three experienced radiologists. Three performance metric measures were used for the comparison. In addition, a radiologist provided quality ratings on a 1 to 10 scale for all of the automatic segmentations. For this pilot study, the authors observed that the differences between the automatic and gold standard contours were larger than the interobserver differences. However, the system performed comparably to the radiologists, achieving an average area intersection ratio of 85.4% compared to an average of 91.2% between two radiologists. The average absolute area error was 21.1% compared to 10.8%, and the average 2D distance was 1.38 mm compared to 0.84 mm between the radiologists. In addition, the quality rating data showed that, despite the very lax assumptions made on the lesion characteristics in designing the system, the automatic contours approximated many of the lesions very well.  相似文献   
7.
We have developed a computer-aided detection (CAD) system to detect clustered microcalcifications automatically on full-field digital mammograms (FFDMs) and a CAD system for screen-film mammograms (SFMs). The two systems used the same computer vision algorithms but their false positive (FP) classifiers were trained separately with sample images of each modality. In this study, we compared the performance of the CAD systems for detection of clustered microcalcifications on pairs of FFDM and SFM obtained from the same patient. For case-based performance evaluation, the FFDM CAD system achieved detection sensitivities of 70%, 80% and 90% at an average FP cluster rate of 0.07, 0.16 and 0.63 per image, compared with an average FP cluster rate of 0.15, 0.38 and 2.02 per image for the SFM CAD system. The difference was statistically significant with the alternative free-response receiver operating characteristic (AFROC) analysis. When evaluated on data sets negative for microcalcification clusters, the average FP cluster rates of the FFDM CAD system were 0.04, 0.11 and 0.33 per image at detection sensitivity level of 70%, 80% and 90% compared with an average FP cluster rate of 0.08, 0.14 and 0.50 per image for the SFM CAD system. When evaluated for malignant cases only, the difference of the performance of the two CAD systems was not statistically significant with AFROC analysis.  相似文献   
8.
A modified one-step process was used to prepare tetracalcium phosphate/monetite/calcium sulfate hemihydrate powder cement mixtures (CAS). The procedure allowed the formation of monetite and calcium sulfate hemihydrate (CSH) in the form of nanoparticles. It was hypothesized that the presence of nanoCSH in small amounts enhances the in vitro bioactivity of CAS cement in relation to osteogenic gene markers in mesenchymal stem cells (MSCs). The CAS powder mixtures with 15 and 5 wt.% CSH were prepared by milling powder tetracalcium phosphate in an ethanolic solution of both orthophosphoric and sulfuric acids. The CAS cements had short setting times (around 5 min). The fast setting of the cement samples after the addition of the liquid component (water solution of NaH2PO4) was due to the partial formation of calcium sulfate dihydrate and hydroxyapatite before soaking in SBF with a small change in the original phase composition in cement powder samples after milling. Nanocrystalline hydroxyapatite biocement was produced by soaking of cement samples after setting in simulated body fluid (SBF). The fast release of calcium ions from CAS5 cement, as well as a small rise in the pH of SBF during soaking, were demonstrated. After soaking in SBF for 7 days, the final product of the cement transformation was nanocrystalline hydroxyapatite. The compressive strength of the cement samples (up to 30 MPa) after soaking in simulated body fluid (SBF) was comparable to that of bone. Real time polymerase chain reaction (RT-PCR) analysis revealed statistically significant higher gene expressions of alkaline phosphatase (ALP), osteonectin (ON) and osteopontin (OP) in cells cultured for 14 days in CAS5 extract compared to CSH-free cement. The addition of a small amount of nanoCSH (5 wt.%) to the tetracalcium phosphate (TTCP)/monetite cement mixture significantly promoted the over expression of osteogenic markers in MSCs. The prepared CAS powder mixture with its enhanced bioactivity can be used for bone defect treatment and has good potential for bone healing.  相似文献   
9.
The corona virus disease 2019(COVID-19) pandemic caused by the severe acute respiratory syndrome corona virus 2(SARS-CoV-2) has had a significant impact on the lives of millions of people,especially those with other concomitant diseases,such as chronic liver diseases.To date,seven corona viruses have been identified to infect humans.The main site of pathological action of these viruses is lung tissue.However,a substantial number of studies have proven that SARSCoV-2 shows affinity towards severa...  相似文献   
10.
OBJECTIVES: The aim of our study was to assess the prognostic role of CA 125 regression during neoadjuvant chemotherapy (NAC) in patients with ovarian cancer (OC) or primary peritoneal serous carcinoma (PPSC) that underwent interval debulking surgery (IOC). MATERIAL AND METHODS: Thirty one patients with advanced OC or PPSC (FIGO stage IIIC and IV) who underwent initial exploratory surgery, followed by NAC containing platinum analogs, have been analyzed, retrospectively. We have used a regression coefficient (RCA 125), which was calculated as following: log10 (CA 125 level measured after two cycles of NAC/baseline CA 125) for statistical analysis. The median value of RCA 125 reached -0.788 and has been used to dichotomize. Optimal IOC has been performed in 67.74% (21/31) patients, suboptimal in 25.81% (8/31) patients and 6.45% (2/31) of patients did not undergo IOC due to the progression of the disease. RESULTS: We have noted significant correspondence between time to progression and RCA 125 in univariate analysis, which we have also confirmed in multivariate analysis (HR 0.27; 95% CI, 0.15-0.96; p = 0.0178). Similarly, we have observed significant relationship between overall survival, RCA 125 and extension IOC in univariate analysis. Multivariate analysis confirmed that RCA 125 was independent prognostic factor, HR-0.18 (95% CI, 0.07-0.56; p = 0.004). In case of patients with high RCA 125, a greater rate of optimal debulking cytoreduction (p = 0.0278, U = 50.0) has been observed. CONCLUSIONS: RCA 125 after two courses of NAC appears to be an important prognostic factor in patients with OC or PPSC, who underwent IOC High RCA 125 during NAC seems to be a good predictive factor in order to achieve optimal IOC.  相似文献   
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