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91.
Out-of-pocket (OOP) payments are the principal means of financing health care throughout much of Asia. We estimate the magnitude and distribution of OOP payments for health care in fourteen countries and territories accounting for 81% of the Asian population. We focus on payments that are catastrophic, in the sense of severely disrupting household living standards, and approximate such payments by those absorbing a large fraction of household resources. Bangladesh, China, India, Nepal and Vietnam rely most heavily on OOP financing and have the highest incidence of catastrophic payments. Sri Lanka, Thailand and Malaysia stand out as low to middle income countries that have constrained both the OOP share of health financing and the catastrophic impact of direct payments. In most low/middle-income countries, the better-off are more likely to spend a large fraction of total household resources on health care. This may reflect the inability of the poorest of the poor to divert resources from other basic needs and possibly the protection of the poor from user charges offered in some countries. But in China, Kyrgyz and Vietnam, where there are no exemptions of the poor from charges, they are as, or even more, likely to incur catastrophic payments.  相似文献   
92.
The soil receives enormous quantities of pesticides and PCBs as a waste product each year due to their wide application. The degradation and eventual fate of these chemicals in the soil largely determine ultimate environmental impact. A survey of an abandoned landfill site has been conducted in a fast developing industrial city Nagpur (India) to assess the degree of environmental contamination with PCBs. The purpose was to determine if any of the mixture of PCBs, Aroclor 1254 and Aroclor 1260 are retained in the compost amended soil of the site despite atmospheric losses possible due the peak summer (100-117 degrees F) in the city. The accuracy and precision for Aroclor 1254 and Aroclor 1260 determinations in the soil samples have been calculated as 76.5 and +/- 0.92 and 83.3 and +/- 1.13 respectively. The samples analysis showed the presence of Aroclor 1254 and Aroclor 1254 and Aroclor 1260 up to the levels of 0.55 and 0.80 mg/g respectively. The maximum total PCBs on dry weight basis are found as 1.2 mg/g.  相似文献   
93.
长鞭红景天化学成分的研究   总被引:10,自引:0,他引:10  
彭江南  葛永潮  李晓晖 《药学学报》1996,31(10):798-800
长鞭红景天化学成分的研究彭江南,葛永潮,李晓晖(军事医学科学院放射医学研究所,北京100850)红景天是滋补强壮药物,目前正引起人们极大的兴趣,现已有一些产品上市。我们曾对数种红景天的化学成分进行过研究[1~4]。长鞭红景天(Rhodiolafast...  相似文献   
94.

Background

Breast cancer in females and prostate cancer in males are two of the most common cancers in the United States, and the literature suggests that they share similar features. However, it is unknown whether the occurrence of these two cancers at the county level in the United States is correlated. We analyzed Caucasian age-adjusted county level average annual incidence rates for breast and prostate cancers from the National Cancer Institute and State Cancer Registries to determine whether there was a spatial correlation between the two conditions and whether the two cancers had similar spatial patterns.

Results

There was a significant correlation between breast and prostate cancers by county (r = 0.332, p < 0.001). This relationship was more pronounced when we performed a geographically-weighted regression (GWR) analysis (r = 0.552) adjusting for county unemployment rates. There was variation in the parameter estimates derived with the GWR; however, the majority of the estimates indicted a positive association. The strongest relationship between breast and prostate cancer was in the eastern parts of the Midwest and South, and the Southeastern U.S. We also observed a north-south pattern for both cancers with our cluster analyses. Clusters of counties with high cancer incidence rates were more frequently found in the North and clusters of counties with low incidence rates were predominantly in the South.

Conclusion

Our analyses suggest breast and prostate cancers cluster spatially. This finding corroborates other studies that have found these two cancers share similar risk factors. The north-south distribution observed for both cancers warrants further research to determine what is driving this spatial pattern.  相似文献   
95.
Synthesized and directly acquired spin-echo images were compared in order to assess the validity of magnetic resonance (MR) image synthesis as a method enabling retrospective formation of images by interactive manipulation of scan parameters. Synthetic images subjectively compared favorably in both accuracy and precision with acquired images when formed for the same values of echo (TE) and repetition times (TR) and for interpolated and extrapolated values of both TE and TR. Plots of synthetic and acquired signals within the same pixel sectors quantitatively showed comparable values for several regions of interest in the brain. Percent error and noise-normalized differences between acquired and synthetic images were tested as a quantitative measure of accuracy. Percent error was consistently less than 5% for brain parenchyma, and synthetic signals were accurate to within four times the noise level at acquisition. The apparent signal-to-noise ratio of synthetic images was comparable, superior, or inferior to similar acquired images, depending on the values of TE and TR. Total acquisition time required for synthetic formation of images for arbitrary values of TE and TR was equivalent to that of a single direct acquisition with a TR of 2,500 msec.  相似文献   
96.
Male rats were given 50 mg/kg molybdenum (Mo; as sodium molybdate) in drinking water for eight consecutive doses. The feeding of Mo was associated with an increased concentration of Mo in body tissues. The highest concentrations of metal were found in the kidney while it was least in blood cells. The accumulation was considered to be significant.  相似文献   
97.
Pande M  Flora SJ 《Toxicology》2002,177(2-3):187-196
Alpha-lipoic acid (LA) has been reported to be highly effective in improving the thiol capacity of the cells and in reducing lead induced oxidative stress. These results suggested its possible role as a therapeutic intervention of lead poisoning in combination with a chelator. We investigated the effects of LA, either alone or when administered in combination with succimer (meso 2,3-dimercaptosuccinic acid; DMSA or one of its analogue monoisoamyl DMSA), in influencing the lead induced alterations in haem synthesis pathway, hepatic, renal and brain oxidative stress and lead concentration from blood and soft tissues. The results suggest a significant lead induced inhibition of delta-aminolevulinic acid dehydratase (ALAD), reduction in glutathione (GSH) and an increased zinc protoporphyrin (ZPP) level in blood, indicating altered heme synthesis pathway. Both the thiol chelators were able to increase blood ALAD activity and GSH level towards normal. The most prominent effect on blood ALAD activity was however observed when monoisoamyl DMSA (MiADMSA) was co-administered with LA. Lead exposure produced significant depletion of hepatic GSH, while, oxidized glutahione (GSSG), thiobarbituric acid reactive substances (TBARS) and catalase activity increased significantly, suggesting hepatic oxidative stress. All the treatments were able to increase hepatic GSH and reduce GSSG levels, while, TBARS level reduced significantly in animals administered LA and MiADMSA, individually or in combination. Lead induced increase in renal GSSG, TBARS levels and catalase activity, were effectively reduced by LA, while, the two chelators when administered alone were effective only in reducing GSSG and catalase activity. The most prominent beneficial effects, however, were observed in animals treated concomitantly with LA and one of the chelators (DMSA or MiADMSA). Brain GSH and GSSG levels decreased moderately while superoxide dismutase (SOD) activity remained statistically unaltered on lead exposure. Brain catalase activity, on the other hand, increased significantly. Administration of LA was effective in reducing these alterations in the brain, however, the best effects were achieved in animals co-administered LA and one of the thiol chelators. The results point to a significant beneficial role of LA in the recovery of altered biochemical variables both during monotherapy and when given in combination with succimer. It however, showed no chelating properties in decreasing lead burden from blood, liver and kidneys except for a significantly more pronounced decrease in brain lead concentration in animals administered LA plus thiol chelators, compared to the effects of chelating agents alone. This is an interesting and notable observation, which requires further exploration. The results thus provide evidence of an encouraging role of LA when given in combination with a thiol chelator in the therapeutic intervention of lead poisoning, particularly in reducing the oxidative stress and brain lead concentration.  相似文献   
98.
Superficial adenopathy is the most frequent clinical manifestation of lymphoma, both at initial workup and later when disease recurs. Data obtained by means of physical examination and ultrasonography (US) of the cervicosupraclavicular, axillary, and inguinal regions were compared for 120 patients, 60 at the time of initial staging and 60 during follow-up for a previously treated lymphoma. Twenty-nine in the second group had recurrent disease, as confirmed with histologic examination. For all 120 patients, US revealed clinically impalpable lesions in an average of 10.8% of cases for the cervicosupraclavicular region, 17.9% for the axillary region, and 4.1% for the inguinal region. Eight of the 29 relapses were not detected at physical examination, and three were demonstrated solely with US. These findings emphasize the value of US exploration of the superficial node-bearing regions in patients with lymphoma, during both initial staging and follow-up.  相似文献   
99.
Treatment of social phobia with gabapentin: a placebo-controlled study.   总被引:11,自引:0,他引:11  
A randomized, double-blind, placebo-controlled, parallel-group study was conducted to evaluate the efficacy and safety of gabapentin in relieving the symptoms of social phobia. Sixty-nine patients were randomly assigned to receive double-blind treatment with either gabapentin (dosed flexibly between 900 and 3,600 mg daily in three divided doses) or placebo for 14 weeks. A significant reduction (p < 0.05) in the symptoms of social phobia was observed among patients on gabapentin compared with those on placebo as evaluated by clinician- and patient-rated scales. Results were similar for the intent-to-treat and week-2 completer populations. Adverse events were consistent with the known side effect profile of gabapentin. Dizziness (p = 0.05), dry mouth (p = 0.05), somnolence, nausea, flatulence, and decreased libido occurred at a higher frequency among patients receiving gabapentin than among those receiving placebo. No serious adverse events or deaths were reported. On the basis of these limited data, it seems that gabapentin offers a favorable risk-benefit ratio for the treatment of patients with social phobia. Further studies are required to confirm this effect and to determine whether a dose-response relationship exists.  相似文献   
100.
We have investigated the frequencies and types of alpha-thal, beta-thal, and Hb variants among nearly 200 inhabitants of villages in the Mandla and Jabalpur districts of Madhya Pradesh in Central India. Over 85% were tribals of the Gond group. alpha-Thal, as -alpha 3.7/and -alpha 4.2/, and the nondeletional Koya Dora mutation were present at the combined frequency of 0.54. There were indications for the presence of other nondeletional types of alpha-thal. alpha-Globin gene triplications were not observed. Four of the six beta-thal alleles observed were in the tribal groups; two (G----C at codon 30 and G----A at IVS-I-1) were found for the first time. The simultaneous presence of an alpha-thal (-alpha/alpha alpha or -alpha/-alpha) greatly improved the clinical and hematological condition of the patients with Hb S-beta(+)-thal (IVS-I-5; G----C). The lower frequency of alpha-thal among the beta-thal heterozygotes (f = 0.32) may indicate that some of the beta-thal alleles in the tribal populations originated from an outside source. Forty-one subjects had SS; all but one had beta S with haplotype #31, while one chromosome had haplotype #17. The presence of an alpha-thal-2 (f = 0.53) in the SS patients did not affect hematological data. The Hb F levels varied between 7.5% and 42.5% with high G gamma values. No difference in Hb F level between males and females was observed. Lower Hb F levels were present in 10 SS patients with an alpha-thal-2 homozygosity (average 16% versus 23.5% for eight SS patients with alpha alpha/alpha alpha) suggesting a decreased formation of alpha gamma dimers in severe alpha chain deficiency. Several younger SS patients (less than 10 years) also had high Hb F levels (32-42%). Variations in the sequence at -530 of the beta-globin gene; i.e. in the so-called silencer sequence, were present in all beta S chromosomes with haplotype #31, but were not considered important for understanding the variability in the Hb F level. gamma-Globin gene deletions (gamma-thal) and triplications were not observed.  相似文献   
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