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1.
Poverty and health. Prospective evidence from the Alameda County Study 总被引:52,自引:0,他引:52
To examine the reasons for the association between socioeconomic status and poor health, the authors examined the nine-year mortality experience of a random sample of residents aged 35 and over in Oakland, California. Residents of a federally designated poverty area experienced higher age-, race-, and sex-adjusted mortality over the follow-up period compared with residents of nonpoverty areas (relative risk = 1.71, 95 per cent confidence interval 1.20-2.44). This increased risk of death persisted when there was multivariate adjustment for baseline health status, race, income, employment status, access to medical care, health insurance coverage, smoking, alcohol consumption, physical activity, body mass index, sleep patterns, social isolation, marital status, depression, and personal uncertainty. These results support the hypothesis that properties of the sociophysical environment may be important contributors to the association between low socioeconomic status and excess mortality, and that this contribution is independent of individual behaviors. 相似文献
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M. I. Manrique-Poyato A. J. Muñoz-Pajares V. Loreto M. D. López-León J. Cabrero J. P. M. Camacho 《Chromosome research》2006,14(6):693-700
We have analysed B chromosome frequency for three consecutive years, B transmission rate at population and individual levels,
clutch size, egg fertility and embryo–adult viability in a natural population of the grasshopper Eyprepocnemis plorans containing two different B chromosome variants, i.e. B2 and B24, the second being derived from the first and having replaced it in nearby populations. From 2002 to 2003 the relative frequency
of both variants changed, although the differences did not reach significance. A mother–offspring analysis showed no significant
effect of any of the two B variants on clutch size, egg fertility or embryo–adult viability, but B24 was more efficiently transmitted than B2 through males from the 2002 season, which explains the observed frequency change. Controlled crosses, at individual level,
showed significant drive through some females for B24 but not for B2, suggesting that this difference in transmission rate might also be important for the substitution process. The analysis
of relative fitness for B2 and B24 carriers for all fitness components, as a whole, showed a significantly better performance of B24-carrying individuals, suggesting that the cumulative effect of these slight differences might contribute to the replacement
of B2 by B24.
Electronic Supplementary Material Supplementary material is available for this article at . 相似文献
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A 47-year-old man, was referred for evaluation of asymptomatic splenomegaly in September 1981, and a diagnosis of hairy cell leukemia (HCL) at the initial clinical stage was made. The patient remained asymptomatic until May 1985, when splenectomy was performed because of anemia and splenomegaly. Bone marrow and liver biopsy specimens showed diffuse infiltration by abnormal tartase resistant acid phosphatase (TRAP) positive lymphocytes with typical aspect of hairy cells. Four months later, he developed fever of unknown origin and, at laparotomy, diffuse retroperitoneal lymph node enlargement and metastatic liver nodules were seen. Lymph node and liver biopsy specimens showed diffuse infiltration by abnormal large lymphocytes, which bore monoclonal surface immunoglobulin M and light chain kappa. Only six cases of non-Hodgkin's lymphoma associated with HCL have been published to date. This report describes an additional case of immunoblastic B-cell lymphoma, preceded 4 years earlier by the diagnosis of HCL. 相似文献
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INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
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