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941.
OBJECTIVES—Because of the rarity of small bowel adenocarcinoma (SBA), little is known about the aetiology of this disease. This study aimed to identify occupational clustering of cases SBA as a systematic approach to new hypotheses on the aetiology of this disease.
METHODS—A European multicentre case-control study was conducted in 1995-7, inclusive. Incident cases aged 35-69 years with SBA (n=168) were recruited before acceptance by a pathologist. Altogether 107 cases and 3915 controls were accepted, of which 79 cases, 579 colon cancer controls, and 2070 population controls were interviewed.
RESULTS—The strongest industrial risk factors for SBA taking account of 10 years' exposure lag were dry cleaning, manufacture of workwear, mixed farming (women), and manufacture of motor vehicles (men). A significantly increased risk of SBA (odds ratio (OR) and 95% confidence interval (95% CI)) was found among men employed as building caretakers, OR 6.7 (1.7 to 26.0) and women employed as housekeepers, OR 2.2 (1.1 to 4.9); general farm labourers, OR 4.7 (1.8 to 12.2); dockers, OR 2.9 (1.0 to 8.2); dry cleaners or launderers, OR 4.1 (1.2 to 13.6); and textile workers (sewers or embroiders), OR 2.6 (1.0 to 6.8). For the last four groups, together with welders OR 2.7 (1.1 to 6.6) (men) an exposure-response pattern was found when calculating the ORs for jobs held 1-5 years and >5 years, with never having held the job as reference. The ORs (95% CIs) for 1-5 years and >5 years were 4.3 (0.4 to 44.0) and 3.5 (0.9 to 13.7), 3.0 (0.3 to 26.2) and 4.3 (0.9 to 21.2), 4.6 (0.4 to 48.1) and 11.0 (2.0 to 60.4), 1.3 (0.2 to 11.0) and 5.8 (2.0 to 17.2), and 2.8 (0.3 to 23.8) and 4.6 (1.3 to 16.6), respectively, for each of these occupations. Among welders, people performing semiautomatic arc welding (MIG/MAG) were identified as a high risk group (OR 5.0 (1.3 to 19.6)).
CONCLUSIONS—This explorative study suggests an increased occurrence of SBA in certain occupations, which needs further evaluation.


Keywords: small intestine; adenocarcinoma; occupational risk factors  相似文献   
942.
BACKGROUND: Deaths from maternal causes represent the leading cause of death among women of reproductive age in most developing countries. It is estimated that the highest risk occurs in Africa, with 20% of world births but 40% of the world maternal deaths. The level of maternal mortality is difficult to assess especially in countries without an adequate vital registration system. Indirect techniques are an attractive cost-effective tool to provide estimates of orders of magnitude for maternal mortality. METHOD: The level of maternal mortality estimated by the sisterhood method is presented for a rural district in the Morogoro Region of Southeastern Tanzania and the main causes of maternal death are studied. Information from region-specific data using the sisterhood method is compared to data from other sources. RESULTS: The maternal mortality ratio (MMR) was 448 maternal deaths per 100,000 live births (95%CI : 363-534 deaths per 100,000 live births). Maternal causes accounted for 19% of total mortality in this age group. One in 39 women who survive until reproductive age will die before age 50 due to maternal causes. The main cause of death provided by hospital data was puerperal sepsis (35%) and postpartum haemorrhage (17%); this is compatible with the main causes reported for maternal death in settings with high levels of maternal mortality, and similar to data for other regions in Tanzania. The sisterhood method provides data comparable with others, together with a cost-effective and reliable estimate for the determination of the magnitude of maternal mortality in the rural Kilombero District.  相似文献   
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We evaluated the clinical performance of assays measuring intact human chorionic gonadotropin alone (i-hCG), intact and nicked human chorionic gonadotropin (i-hCG and hCGn), free beta-subunit (free beta-hCG) and total beta-human chorionic gonadotropin (t-hCG) using different commercial kits, in a group of bladder carcinoma patients with ectopic human chorionic gonadotropin (hCG) secretion, at diagnosis and during treatment. The diagnostic sensitivity obtained ranged between 63.6% and 75.7% (t-hCG assays), 72.7% (free beta-hCG assay), 18.2% (i-hCG and hCGn) and 6% (i-hCG assay). Median increases of hCG during treatment in patients with chemotherapy resistance ranged from 4.9 to 6.9 for t-hCG and free beta-hCG assays and from 1.4 to 3.2 for i-hCG and i-hCG plus hCGn assays. Median decreases when chemotherapy was efficient ranged from 2.8 to 3.3 (t-hCG and free beta-hCG assays) and from 1.1 to 1.5 (i-hCG and i-hCG plus hCGn assays). We conclude that t-hCG and free beta-hCG are the most suitable assays for the management of bladder carcinoma patients as the ectopic secretion of chorionic gonadotropin is mainly due to the free beta-subunit.  相似文献   
946.
Several novel semicarbazone derivatives were prepared from 5-nitro-2-furaldehyde or 5-nitrothiophene-2-carboxaldehyde and semicarbazides bearing a spermidine-mimetic moiety. All derivatives presented the E-configuration, as determined by NMR-NOE experiments. These compounds were tested in vitro as potential antitrypanosomal agents, and some of them, together with the parent compounds, 5-nitro-2-furaldehyde and 5-nitrothiophene-2-carboxaldehyde semicarbazone derivatives, were also evaluated in vivo using infected mice. Structure-activity relationship studies were carried out using voltammetric response and lipophilic-hydrophilic balance as parameters. Two of the compounds (1 and 3) displayed the highest in vivo activity. A correlation was found between lipophilic-hydrophilic properties and trypanocidal activity, high R(M) values being associated with low in vivo effects.  相似文献   
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949.
Polymorphonuclear leukocyte (PMN) adherence to nylon was studied in the umbilical cord blood of 33 full-term, healthy newborns (NBs) during delivery. The results were compared to the adherence of PMN of peripheral blood in 50 healthy adult blood bank donors. PMN adherence in the NBs (56.64 +/- 3.24) was found to be significantly higher (p less than or equal to 0.01) than in the adults (47.03 +/- 2.01). PMN adherence, either in adults or NBs, is not related to leukocytes, platelets or hematocrit values. It was found to be related only to the percentage of total leukocyte adherence. Also using scanning electron microscopy (SEM), the ultrastructure of the adherence process was analyzed. In these studies we observed a higher tendency to adopt fusiform disposition in the PMN of the adult population. These results suggest that NB PMNs are hyperadherent and that they show a cellular rigidity and a resistance to deformation that could be responsible for the chemotactic alterations previously described in neonates.  相似文献   
950.
CASE REPORT: We describe an acute retinal pigment epithelitis (A.R.P.E) case in a young woman who noticed an acute decreased vision and color vision defects. The patient was treated with systemic nonsteroidal anti-inflammatory drugs (NSAIDs) with recovery of visual acuity to normal in three weeks. DISCUSSION: We highlight the debut with important decrease of visual acuity at levels that are not common in this illness. The disturbance in color vision is a rare symptom. The visual acuity recovery in a short period of time is what usually happens, and in this case it is just three weeks, not knowing how it relates to NSAID.  相似文献   
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