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81.
Rates of, and the factors affecting, cycle helmet use among secondary schoolchildren in East Sussex and Kent 下载免费PDF全文
Objectives—To assess the level of cycle helmet wearing among young people in two counties in the South East of England in 1994, and to identify the factors associated with helmet wearing. 相似文献
82.
S. Roth P. Kristo A. Auranen M. Shayehgi S. Seal N. Collins R. Barfoot N. Rahman P. J. Klemi S. Gr??nman L. Sarantaus H. Nevanlinna R. Butzow A. Ashworth M. R. Stratton L. A. Aaltonen 《British journal of cancer》1998,77(8):1199-1202
Inherited susceptibility to ovarian cancer has been associated with germline defects at several loci. The major known ovarian cancer susceptibility gene is BRCA1 on chromosome 17q, which confers a risk of approximately 60% by the age of 70 years. Truncating mutations in BRCA2 on chromosome 13q also predispose to ovarian cancer, although they confer a lower risk than mutations in BRCA1. We have studied the molecular basis of ovarian cancer predisposition in a Finnish family with three affected sisters. Analysis of polymorphic markers provided evidence against linkage to BRCA1, but the sibship was consistent with linkage to BRCA2. Conformation-sensitive gel electrophoresis was used to screen the entire coding sequence of BRCA2. A G to A transition at nucleotide 8702 was observed, which is predicted to convert glycine 2901 to aspartate in the encoded protein. This sequence variant was not detected in 220 cancer-free Finnish control individuals, or in several hundred cancer families of many nationalities previously screened for BRCA2 mutations. Taken together with the fact that this amino acid residue and the surrounding region of BRCA2 is identical in mouse and chicken, the data suggest that this alteration is a disease-causing BRCA2 missense mutation. Previously published data indicate that the risks of breast and ovarian cancer conferred by BRCA2-truncating mutations varies with the position of the mutation in the gene. The missense mutation reported here suggests that the BRCA2 domain including and surrounding glycine 2901 may be more important in preventing neoplastic transformation in ovarian epithelium than in breast epithelium. 相似文献
83.
S A Al-Suleiman M H Al-Sibai F E Al-Jama A R El-Yahia Jessica Rahman M S Rahman 《Journal of obstetrics and gynaecology》2004,24(3):259-263
This was an institutional study of all maternal deaths that occurred among 56422 total births at the King Faisal University Hospital, Al-Khobar, Saudi Arabia, between 1983 and 2002. The underlying cause of each maternal death and potentially avoidable factors were analysed. There were 16 maternal deaths in the hospital during the study period, giving a maternal mortality rate of 28.4/100,000 births. The leading cause of death was haemorrhage in seven (43.75%) patients, followed by pulmonary embolism in four (25%) and general anaesthesia in two (12.5%) mothers. The risk factors noted were maternal age 35 years and parity 5 coupled with iron deficiency anaemia. The main avoidable factors were failure of the patients to seek timely medical care and to follow medical advice. More than half the number of direct obstetrical causes of death was thought to be preventable. A rapidly changing attitude of women towards childbirth is occurring through progressively increasing female education and community health programmes in the region. Further reduction of maternal mortality rates in the community is envisaged through greater patient acceptance of medical advice, family spacing and proficient obstetric services. 相似文献
84.
Edvardas Kaminskas Ann Farrell Sophia Abraham Amy Baird Li-Shan Hsieh Shwu-Luan Lee John K Leighton Hasmukh Patel Atiqur Rahman Rajeshwara Sridhara Yong-Cheng Wang Richard Pazdur 《Clinical cancer research》2005,11(10):3604-3608
PURPOSE: This article summarizes data submitted to the U.S. Food and Drug Administration for marketing approval of azacitidine as injectable suspension (Vidaza, Pharmion Corporation, Boulder, CO) for treatment of patients with myelodysplastic syndrome. EXPERIMENTAL DESIGN: In one phase 3 controlled trial, 191 study subjects were randomized to treatment with azacitidine or to observation; an additional 120 patients were treated with azacitidine in two phase 2 single arm studies. The primary efficacy end point was the overall response rate, defined as complete or partial normalization of peripheral blood counts and bone marrow blast percentages for at least 4 weeks. RESULTS: In the controlled trial, the overall response rate was 15.7% in the azacitidine treatment group; there were no responders in the observation group (P < 0.0001). Response rates were similar in the two single arm studies. During response patients stopped being red cell or platelet transfusion dependent. Median duration of responses was at least 9 months. An additional 19% of azacitidine-treated patients had less than partial responses, most becoming transfusion independent. The most common adverse events attributed to azacitidine were gastrointestinal, hematologic, local (injection site), and constitutional. There were no azacitidine-related deaths. CONCLUSIONS: On May 19, 2004 the U.S. Food and Drug Administration approved azacitidine as injectable suspension for treatment of patients with the following myelodysplastic syndrome subtypes: refractory anemia or refractory anemia with ringed sideroblasts (if accompanied by neutropenia or thrombocytopenia or requiring transfusions), refractory anemia with excess blasts, refractory anemia with excess blasts in transformation, and chronic myelomonocytic leukemia. Full prescribing information is available at http://www.fda.gov/cder/foi/label/2004/050794lbl.pdf. Azacitidine is the first agent approved for treatment of myelodysplastic syndrome. 相似文献
85.
Huseyin Buyukbayram Sebahattin Cureoglu Adem Arslan A. Rahman I ikakdogan 《Cancer investigation》2005,22(2):195-202
The objective of this study was to investigate the prognostic significance of p53, and proliferative cell nuclear antigen (PCNA) in laryngeal squamous cell carcinoma (LSCC). Sixty pathologic specimens from the patients with LSCC were examined for the expression of the p53 and PCNA, with complete follow-up data. Sixty-three percent of the cases displayed nuclear p53 overexpression. There was a correlation between p53 overexpression and histological grades (p = 0.03), and localization site (p = 0.05). Median of PCNA index was 42.2 (range 5.9 to 85.2). There was no difference between the p53 overexpression group and the normal group in proliferative activity determined by PCNA (p = 0.73). In univariate analyses, localization site, grade, stage, invasion pattern, lymph node status, were significant factors in estimating disease free survival (DFS). Grade was the most important factor affecting recurrence (p = 0.002). In multivariate analyses, grade was the only significant predictor for DFS (p = 0.001). Grade (p = 0.001) and invasion pattern (p = 0.03) were found to be significant predictors of overall survival. In conclusion, the histological grade was the most reliable important prognostic factor. Further studies are necessary to facilitate understanding of the mechanisms of laryngeal carcinogenesis. 相似文献
86.
Donna E. Hansel Ayman Rahman Robb E. Wilentz Ie-ming Shih Michael T. McMaster Charles J. Yeo Anirban Maitra MD 《Journal of gastrointestinal cancer》2005,35(1):15-23
HLA-G belongs to the nonclassical MHC class Ib group of molecules and has been implicated in mediating immune-responsiveness in various cancerous and non-cancerous cell types. We have examined HLA-G expression in a number of human gastrointestinal malignancies, including pancreatic ductal adenocarcinoma, ampullary cancer, biliary cancer, and colorectal cancer by immunolabeling analysis. We used indices of <5% (negative), 6–25%, 26–50%, 51–75%, and >75% (diffuse) to subclassify lesions based on percentage of positive cell labeling. Across all cancer subtypes, 52–79% of lesions demonstrated expression of HLA-G, with up to 33% of lesions demonstrating diffuse (>75%) expression. In addition, we utilized the neoplastic progression model of colorectal cancer to evaluate HLA-G protein expression in normal colon, tubulovillous adenomas, invasive cancer, and liver metastases arising from colorectal cancer. Focal HLA-G expression was detected in regions of normal colon adjacent to sites of adenomatous and cancerous lesions, as well as in all stages of cancer progression. Overall, the percentage of diffusely (>75%) labeled lesions appeared increased in preneoplastic and neoplastic conditions, as compared to normal colon. Specifically, tubulovillous adnenomas demonstrated pronounced diffuse labeling in 58% of lesions examined. No correlation with HLA-G expression and CD4+ or CD8+ T cells was identified. We propose that HLA-G expression is upregulated in a large percentage of gastrointestinal lesions and may serve to mediate immuneresponsiveness in certain instances. 相似文献
87.
Shahroz Saleem Muhammad Irfan Muhammad Yasin Naz Shazia Shukrullah Muhammad Adnan Munir Muhammad Ayyaz Abdullah Saeed Alwadie Stanislaw Legutko Jana Petr Saifur Rahman 《Materials》2022,15(10)
This study investigated the production of Cu2+-doped CoFe2O4 nanoparticles (CFO NPs) using a facile sol−gel technique. The impact of Cu2+ doping on the lattice parameters, morphology, optical properties, and electrical properties of CFO NPs was investigated for applications in electrical devices. The XRD analysis revealed the formation of spinel-phased crystalline structures of the specimens with no impurity phases. The average grain size, lattice constant, cell volume, and porosity were measured in the range of 4.55–7.07 nm, 8.1770–8.1097 Å, 546.7414–533.3525 Å3, and 8.77–6.93%, respectively. The SEM analysis revealed a change in morphology of the specimens with a rise in Cu2+ content. The particles started gaining a defined shape and size with a rise in Cu2+ doping. The Cu0.12Co0.88Fe2O4 NPs revealed clear grain boundaries with the least agglomeration. The energy band gap declined from 3.98 eV to 3.21 eV with a shift in Cu2+ concentration from 0.4 to 0.12. The electrical studies showed that doping a trace amount of Cu2+ improved the electrical properties of the CFO NPs without producing any structural distortions. The conductivity of the Cu2+-doped CFO NPs increased from 6.66 × 10−10 to 5.26 × 10−6 ℧ cm−1 with a rise in Cu2+ concentration. The improved structural and electrical characteristics of the prepared Cu2+-doped CFO NPs made them a suitable candidate for electrical devices, diodes, and sensor technology applications. 相似文献
88.
A Distinctive Pattern of Beauveria bassiana‐biotransformed Ginsenoside Products Triggers Mitochondria/FasL‐mediated Apoptosis in Colon Cancer Cells 下载免费PDF全文
Sang Il Gum Md Khalilur Rahman Jong Soon Won Min Kyung Cho 《Phytotherapy research : PTR》2016,30(1):136-143
Ginseng is one of the most commonly used adaptogens. Transformation into the minor ginsenosides produces compounds with more effective action. Beauveria bassiana, a teleomorph of Cordyceps bassiana, is a highly efficient producer of mammalian steroids and produces large amounts of sugar‐utilizing enzymes. However, the fermentation of steroid glycosides in ginseng with B. bassiana has never been studied. Thus, we evaluated the bioconversion of the major ginsenosides in white ginseng by B. bassiana. Interestingly, B. bassiana increased the total amount of protopanaxadiols and hydrolyzed Rb1 into minor ginsenosides, exhibiting high levels of Rd and Rg3, as well as moderate levels of Rb2 and Rc analyzed by high‐performance liquid chromatography coupled with evaporative light‐scattering detection. The β‐glucosidase activity was highly increased, which led to the selective elimination of sugar moiety at the 20‐C position of Rb1 to Rd, followed by Rg3. Rb2 and Rc accumulated because of the minimal activities of α‐L‐arabinopyranosidase and α‐L‐arabinofuranosidase, respectively. The fermentation product exerted dose‐dependent cytotoxicity in HCT‐15 cells, which are resistant to ginseng. The product, but not white ginseng, exhibited apoptotic effects via the Fas ligand and caspase 8/9. This study demonstrates for the first time that the B. bassiana‐fermented metabolites have potent apoptotic activity in colon cancer cells, linking to a therapeutic use. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
89.
Farooq Ahmed Najma Iqbal Malik Nudra Malik Madeeha Gohar Qureshi Muhammad Shahzad Muhammad Shahid Sidra Zia Kun Tang 《Nutrients》2022,14(13)
Severe Acute Malnutrition (SAM) is a serious public health problem in many low- and middle-income countries (LMICs). Therapeutic programs are often considered the most effective solution to this problem. However, multiple social and structural factors challenge the social inclusion, sustainability, and effectiveness of such programs. In this article, we aim to explore how poor and remote households face structural inequities and social exclusion in accessing nutrition-specific programs in Pakistan. The study specifically highlights significant reasons for the low coverage of the Community Management of Acute Malnutrition (CMAM) program in one of the most marginalized districts of south Punjab. Qualitative data are collected using in-depth interviews and FGDs with mothers and health and nutrition officials. The study reveals that mothers’ access to the program is restricted by multiple structural, logistical, social, and behavioral causes. At the district level, certain populations are served, while illiterate, and poor mothers with lower cultural capital from rural and remote areas are neglected. The lack of funding for nutrition causes the deprioritization of nutrition by the health bureaucracy. The subsequent work burden on Lady Health Workers (LHWs) and the lack of proper training of field staff impact the screening of SAM cases. Moreover, medical corruption in the distribution of therapeutic food, long distances, traveling or staying difficulties, the lack of social capital, and the stigmatization of mothers are other prominent difficulties. The study concludes that nutrition governance in Pakistan must address these critical challenges so that optimal therapeutic coverage can be achieved. 相似文献
90.
Muhammad Irfan Irshad Ahmad Shazia Shukrullah Humaira Hussain Muhammad Atif Stanislaw Legutko Jana Petru Michal Hatala Muhammad Yasin Naz Saifur Rahman 《Materials》2022,15(13)
The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti3C2, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti3C2 nanosheets. In constructing these heterojunctions, Ti3C2 nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti3C2 composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti3C2 composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti3C2 Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti3C2 composition with 30 wt.% of Ti3C2, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti3C2 as a low-cost co-catalyst. 相似文献