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71.
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   
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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   
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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   
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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   
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In recent times engineered nanoparticles have been receiving much attention from researchers due to their extensive use in a variety of chemical, biological, and industrial areas. Their physiochemical properties have led to a number of uses in commercial products. Considering their broad applications, with increasing human contact the risks of exposure are also increasing. In vivo toxicity experiments involving administering nanoparticles to living organisms have shown their adverse effects on organ development and reproduction. Nanoparticles can be considerably more toxic than the large-sized particles since they can move relatively freely compared to bulkier molecules. Henceforth, it is our duty to assess the harmful health consequences associated with human exposure to nanoparticles in order to improve safe production and use. We will review the current applications of nanoparticles, and issues related to their toxicity. We will focus on safety regulations, risk assessment and regulatory guidelines of nanoparticles. The validation and standardization of nanotoxicity tests will further promote safe applications of nanotechnology in our daily lives.  相似文献   
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