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1.
H. S. King  D. T. Wigle  G. B. Hill  J. Silins 《CMAJ》1982,127(7):591-594
Death certificates were reviewed for the 543 Alberta women who died during the period 1969 through 1978 and for whom the underlying cause of death was coded as uterine cancer. To evaluate the recorded cause of death Alberta Cancer Registry records, which existed for 97% of the women, were examined. Calculations from the revised information showed an increase in the mortality of cancer of the corpus uteri and a decrease in the mortality of cancer of the cervix uteri over the 10-year period, but neither was statistically significant. During the same period in Alberta the incidence of cancer of the corpus uteri increased significantly and the incidence of cancer of the cervix uteri decreased significantly.  相似文献   

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OBJECTIVE--Correlation of the urinary albumin excretion rate and the risk of death among elderly subjects. DESIGN--216 Subjects aged 60-74 whose urinary albumin excretion rate had been determined were followed up 62-83 months later. SETTING--Municipality of Fredericia, Denmark. SUBJECTS--223 People who had been selected as control subjects for diabetics found during a systematic screening for diabetes of all people aged 60-74 living in the municipality of Fredericia, Denmark. Of these subjects, 216 had an extensive clinical and biochemical examination within a few weeks of selection. MAIN OUTCOME MEASURE--Death. RESULTS--The median urinary albumin excretion rate was 7.52 micrograms/min. Eight of those with a rate below the median died compared with 23 with a rate equal to or greater than the median (p = 0.0078). The median albumin excretion rate in the 31 who died was 15.00 micrograms/min. Cardiovascular disease was the most common cause of death in both groups. A multivariate regression analysis of survival data was performed using the proportional hazards model. Besides albumin excretion rate, male sex, serum creatinine concentration, and hypertension were found to be of prognostic value. CONCLUSIONS--The association between the albumin excretion rate and mortality that has been described in recent years in patients with diabetes mellitus may be present in elderly people in general, even when other known risk factors are taken into account.  相似文献   

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Insulin-like growth factor binding protein-1 (IGFBP-1) has been implicated in the development of cardiovascular disease, but it is not known whether IGFBP-1 is related to cardiovascular mortality. We examined the relation of circulating IGFBP-1 to death from coronary heart disease, cardiovascular disease, and all causes in a cohort study consisting of 622 men aged 65 - 84 years, at baseline in 1984. Fasting serum IGFBP-1 and other risk factors were measured in 1984 and 1989. Cardiovascular events for those who died between 1984 and 1995 were analyzed, and cardiovascular diagnoses were coded centrally according to standardized procedures. Of the 622 men, 358 died between 1984 and 1995; 160 deaths were due to cardiovascular causes, 113 of which were coronary deaths. High fasting serum IGFBP-1 concentration (> 75 percentile) in 1984 was associated with increased five-year total mortality (OR 2.05, 95 % CI 1.41 - 2.99; p < 0.0002), cardiovascular mortality (OR 2.20, 95 % CI 1.37 - 3.50; p < 0.0009) and coronary heart disease mortality (OR 2.29, 95 % CI 1.35 - 3.88; p < 0.002). After adjustment for age, high serum IGFBP-1 concentrations still carried an increased risk of total mortality due to (OR 1.73, 95 % CI 1.16 - 2.59; p < 0.007), cardiovascular (OR 1.91 95 % CI 1.18 - 3.09; p < 0.008) and coronary heart disease (OR 2.02. 95 % CI 1.18 - 3.47; p < 0.01). In conclusion, high fasting serum IGFBP-1 is related to increased five-year total and cardiovascular mortality in elderly men.  相似文献   

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BACKGROUND: Intensive medical care of women with diabetes has reduced their risks of bearing infants with congenital anomalies. To assess the preventive potential of preconceptional care, the data of a population-based study of cardiovascular malformations (CVM) were analyzed to determine the morphogenetic specificity of maternal diabetes risks, the morbidity and mortality of the infants, and maternal characteristics that might affect these risks. METHODS: The Baltimore-Washington Infant Study was a case-control study (1981-1989) that included all live born infants with confirmed CVM; control infants were a representative sample of the birth cohort. A questionnaire administered in home visits recorded parental information on social, medical, occupational, and environmental factors. For these analyses of preconceptional diabetes risks, the case group excluded chromosomal and mendelian disorders and was divided into 3 developmental categories and 12 diagnostic groups. RESULTS: Preconceptional maternal diabetes was strongly associated with CVM of early embryonic origin (odds ratio [OR] = 4.7, 95% confidence interval [CI] 2.8-7.9) and with cardiomyopathy (OR = 15.1, 95% CI 5.5-41.3), but not with obstructive and shunting defects (OR = 1.4, 95% CI 0.7-3.0). There was heterogeneity within these developmental categories: among laterality defects, diabetes was associated only with cardiovisceral and atrioventricular discordance (OR = 10.0, 95% CI 3.7-27.0); among outflow tract anomalies, the risk was strongly associated with normally related great arteries (OR = 6.6, 95% CI 3.2-13.3) but not with simple transpositions; and among atrioventricular septal defects, diabetes was associated with the complete but not with the partial forms (OR = 22.8, 95% CI 7.4-70.5). The association in early CVM was strongest among infants with multisystem, predominantly VACTERL, anomalies. All-cause mortality of infants with CVM was 39% among those with diabetic mothers and 17.8% in those with nondiabetic mothers. Deceased infants of diabetic mothers were also more likely to have extracardiac anomalies (P = 0.041), to be born prematurely (P = 0.007), and to have low birth weight (P = 0.011). Multivariate analyses of maternal factors revealed no significant confounders of the diabetes associations. CONCLUSIONS: The evidence of diabetes-induced major cardiac defects is of urgent clinical significance. The effectiveness of early preconceptional care in the prevention of congenital anomalies has been demonstrated repeatedly.  相似文献   

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Current proposals for the catalytic mechanism of aspartic proteinases are largely based on X-ray structures of bound oligopeptide inhibitors possessing nonhydrolyzable analogues of the scissile peptide bond. However, the positions of protons on the catalytic aspartates and the ligand in these complexes have not been determined with certainty. Thus, our objective was to locate crucial protons at the active site of an inhibitor complex since this will have major implications for a detailed understanding of the mechanism of action. We have demonstrated that high-resolution neutron diffraction data can be collected from crystals of the fungal aspartic proteinase endothiapepsin bound to a transition state analogue (H261). The neutron structure of the complex has been refined at a resolution of 2.1 A to an R-factor of 23.5% and an R(free) of 27.4%. This work represents the largest protein structure studied to date by neutron crystallography at high resolution. The neutron data demonstrate that 49% of the main chain nitrogens have exchanged their hydrogen atoms with D2O in the mother liquor. The majority of residues resisting exchange are buried within core beta-sheet regions of the molecule. The neutron maps confirm that the protein has a number of buried ionized carboxylate groups which are likely to give the molecule a net negative charge even at very low pH, thereby accounting for its low pI. The functional groups at the catalytic center have clearly undergone H-D exchange despite being buried by the inhibitor occupying the active site cleft. Most importantly, the data provide convincing evidence that Asp 215 is protonated and that Asp 32 is the negatively charged residue in the transition state complex. This has an important bearing on mechanistic proposals for this class of proteinase.  相似文献   

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OBJECTIVE--To describe mortality by suicide and other causes of death in a group of patients who attempted suicide, and to identify predictive factors. DESIGN--10 year follow up study based on records of suicide attempters in 1980. SETTING--Poisoning treatment centre at a general hospital. SUBJECTS--974 patients aged 15 and over referred to the poisoning treatment centre after deliberate self poisoning. MAIN OUTCOME MEASURES--Death by different causes registered in the Danish death cause register. RESULTS--In 10 years of follow up 306 patients died: 103 by suicide, 131 from natural causes, and 31 by accident; five were murdered, and in 36 cases the cause of death was uncertain. The standard mortality ratio was 550. Cause specific standardised mortality rates were 2960 for suicide, 236 for natural causes, 1256 for accidents, and 5459 for uncertain causes. In a Cox regression analysis, high risk factors for subsequent suicide were: more than one previous suicide attempt (relative risk 2.25), living alone (2.28), and age (1.03 per year). Predictors of death by natural causes were receiving a pension (1.69), drug misuse (2.72), more than one previous suicide attempt (2.25), age (1.06 per year), and male sex (2.49). The group of patients fulfilling at least one high risk criterion for later suicide differed significantly from the rest of the patient group in incidence of suicide, but both sensitivity and specificity were low. CONCLUSIONS--Most patients who attempted suicide were at high risk of succeeding because the risk factors, though significant, are not very specific. A strategy to prevent suicide must be directed toward the majority of those who attempt suicide.  相似文献   

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G J Storr 《Radiation research》1992,131(3):235-242
The discrete-ordinates transport computer code DORT has been used to develop a two-dimensional cylindrical phantom model for use as a tool to assess beam design and dose distributions for boron neutron capture therapy. The model uses an S8 approximation for angular fluxes and a P3 Legendre approximation for scattering cross sections. A one-dimensional discrete-ordinates model utilizing the computer code ANISN was used to validate the energy-group structure used in the two-dimensional calculations. In the two-dimensional model the effects of varying basic parameters such as aperture width, neutron source energy, and tissue composition have been studied. Identical results were obtained when comparing narrow beam calculations to fine-mesh higher-order Sn treatments (up to S32), and with P5 cross sections. It is shown that, when the correct assessment volume is used, narrow beams will give little or no advantage for therapy even with an optimum-energy ideal neutron beam.  相似文献   

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A simple method has been devised to determine the rate constants of the aldehyde hydration of pyridoxal-P by coupling the hydration reaction to the formation of a Schiff base derived from free pyridoxal-P and a primary amine present in excess. The primary amine component to be chosen should have a pK value very close to the pH at which the hydration ratio is to be determined. At pH 7.8 glycine ethyl ester is particularly well suited as primary amine component due to its favorable pK of 7.83. The overall reaction consisting of two independent reaction steps was monitored at different wavelengths and analyzed by means of the formal integration method. The rate constant of the forward reaction (kh1 = kh [H2O]) and of the reverse reaction (kd) were found to be 1.99 s?1 and 8.09 s?1, respectively. The corresponding equilibrium constant is 0.25.  相似文献   

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Distinct biological properties of the ortho-carboranyl (1,2-dicarba-closo-dodecaboranyl) glycosides 1, 2 and 3 were evaluated to estimate the suitability of these compounds for cancer treatment by boron neutron capture therapy. The boron uptake into B16-Melanoma cells was significantly higher by incubating the cells with aqueous solutions of carboranyl glucoside 1 (11.2 ppm after 3h), lactoside 2 (13.2 ppm after 12h) and maltoside 3 (20.0 ppm after 24h) compared with solutions of clinically used p-boronophenylalanine (BPA) 5 (3.1 ppm after 24h). Carboranyl maltoside 3 was more effective than boron-10 enriched 5 in killing C-6 rat glioma cells by incubating the cells with the compound and subsequent treatment with thermal neutrons. 3 was also administrated iv, in concentrations of 25 mg boron/kg body weight to rats bearing brain tumors. After a period of 4h after administration the concentration of boron in the tumor tissue was 3.0 ppm.  相似文献   

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Endocrine therapy is a major treatment modality for the systemic management of breast cancer. In comparison with alternatives such as chemotherapy, hormone manipulations have the advantage of lower toxicity but suffer from the disadvantages of producing responses in only 30-40% of patients with metastatic disease and seldom being curative. Nevertheless in recent years there have been significant advances in the endocrine treatment of breast cancer which have stemmed from a better understanding of the sources from which breast tumours may be supplied with hormones, the mechanism by which hormones regulate tumour proliferation and the more accurate identification of hormone sensitive tumours. As a result agents such as antioestrogens, aromatase inhibitors. LHRH agonists have largely superseded surgical and radiological ablation of endocrine organs. The major reduction in morbidity associated with these medical regimes means that they are much more acceptable to patients and may be used as adjuvants to local treatment of the breast in patients with "earlier" stages of the disease. At the same time patients can now be offered rational treatment selected on the basis of tumour biology rather than on more empirical criteria. The aims of this review are to provide details of the research which has led to this progress in endocrine treatment of breast cancer and to put into perspective the prospects for further advances.  相似文献   

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The relative proportion of Bacteroidetes to Firmicutes is decreased in obese people. This imbalance in gut microbiota generates signals controlling the expression of genes by the epithelial intestinal cells. Both dairy and non-dairy probiotics increase body weight, reportedly through Lactobacillus species growth in the gut. On the other hand, daily intake of some fruits and drinks such as three apples or three pears or grapefruit, or green tea, which all are rich in polyphenols, can significantly reduce body weight in obese people. Metabolism of polyphenols by microbiota involves the cleavage of glycosidic linkages. Glycans, which are the product of glycosidic cleavage, are necessary for survival of the intestinal microbiota as a nutrient foundation. There are two pivotal points: (i) Firmicutes possess a disproportionately smaller number of glycan-degrading enzymes than Bacteroidetes, (ii) Firmicutes are more repressed than the Bacteroidetes by phenolic compounds' antimicrobial properties. The Bacteroidetes community prevails following dietary polyphenol intake and its fermentation to phenolic compounds, due to having more glycan-degrading enzymes, so this may thus be a mechanism by which dietary polyphenols exert their weight lowering effect. I suggest that future studies utilize clone libraries and fingerprinting techniques enabling identification of the composition and community structure of the microbiota, and dot blot hybridization or fluorescent in situ hybridization to analyze abundance of particular taxa in obese and individuals. A supplementation with polyphenols with high bioavailability in obese individuals with higher Firmicutes/Bacteroides community ratio phenotype, when associated to a probiotic restricted diet, is proposed for weight loss; this hypothesis could have relevant implication in planning a successful dietary regimen and/or neutraceutical/pharmaceutical preparations for achieving and maintaining a normal body weight in obese individuals, especially including much more use of polyphenol-rich foodstuffs and/or polyphenol-rich syrups, and including low amounts of probiotic-rich foodstuffs like yogurt, soy yogurt, or as probiotic supplements.  相似文献   

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Extant apes experience early sexual maturity and short life spans relative to modern humans. Both of these traits and others are linked by life-history theory to mortality rates experienced at different ages by our hominin ancestors. However, currently there is a great deal of debate concerning hominin mortality profiles at different periods of evolutionary history. Observed rates and causes of mortality in modern hunter-gatherers may provide information about Upper Paleolithic mortality that can be compared to indirect evidence from the fossil record, yet little is published about causes and rates of mortality in foraging societies around the world. To our knowledge, interview-based life tables for recent hunter-gatherers are published for only four societies (Ache, Agta, Hadza, and Ju/'hoansi). Here, we present mortality data for a fifth group, the Hiwi hunter-gatherers of Venezuela. The results show comparatively high death rates among the Hiwi and highlight differences in mortality rates among hunter-gatherer societies. The high levels of conspecific violence and adult mortality in the Hiwi may better represent Paleolithic human demographics than do the lower, disease-based death rates reported in the most frequently cited forager studies.  相似文献   

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Male and female hybrid BCF1 (C57BL/6 BdxBALB/c Bd) were exposed to total neutron doses of 0.06, 0.12, 0.24, and 0.48 Gy in fractions over a period of 24 weeks. The fractionation regimens were: 24 weekly fractions of 0.0025 Gy, 12 fractions of 0.01 Gy every 2 weeks, 6 fractions of 0.04 Gy every 4 weeks, and 3 fractions of 0.16 Gy every 8 weeks. In order to detect any change in susceptibility with age over the period of exposures from 16 weeks to 40 weeks of age, mice were exposed to single doses of 0.025, 0.05, 0.10, and 0.2 Gy at 16 and 40 weeks of age. These experiments were designed to test whether the initial parts of the dose-response relationships for life shortening and cancer induction could be determined economically by using fractionated exposures and whether or not the initial slopes were linear. The conclusions were that for life shortening and most radiogenic cancers, the dose-effect curves are linear and that fractionation of the neutron dose has no effect on the magnitude of the response of equal total doses over the range of doses studied. The ratio of such initial slopes and comparable linear initial slopes for a reference radiation should provide maximum and constant relative biological effectiveness values.  相似文献   

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A number of glycyl-tRNA synthetase (glyS) mutants have been isolated as glycine auxotrophs in Salmonella typhimurium. One of the mutants, glyS141, has a glycyl-tRNA synthetase with a Km for glycine that is 700 times higher than the wild-typeKm. Prototrophic revertants glyS141 occur at high spontaneous frequencies (>5 × 10?5). The majority of these revertants contain large tandem duplications including the mutant glyS gene. Some of the duplications cover at least 22% of the chromosome. The duplications overlap with a large duplication isolated previously by a different selection procedure (Straus &; Hoffmann, 1975). Evidence has been obtained which suggests that formation of the duplications may occur by recA-dependent recombination. The Gly+ phenotype of revertants carrying the duplications does not appear to be explainable simply by the increased gene dosage of glyS.  相似文献   

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