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1.
Summary The application of the critical electrolyte concentration (CEC) concept to the differentiation of acidic glycosaminglycans (mucopolysaccharides) is described. Alcian Blue 8GX stains with increasing selectivity as increasing amounts of magnesium chloride are incorporated into the dye solution. Model experiments with pure polyanions, or artifically carboxylated, phosphorylated and sulphated liver sections, showed that binding of dye to carboxylate or phosphate groups ceased at low electrolyte concentrations (< 0.3M) whereas dye continued to be held by sulphate ester groups at concentrations five to ten times as high. The similarity to the well established cetylpyridinium system for polyanion fractionation is discussed.Sections of tissues chosen to contain predominantly or characteristically carboxylated mucins, and/or sulphate ester polyanions showed a staining pattern entirely similar to the model sections. Goblet cell mucin in rat ileum stained at < 0.4M MgCl2, Cartilage at < 0.6M MgCl2, mast cells at < 0.75M, and corneal stroma at < 1.0M. These results are in agreement with the known contents of sialo-mucin, chondroitin sulphate, heparin and keratansulphate, respectively. The conditions in which this principle can be used in a practical technique are described.The new and more precise terminology of Jeanloz (1960) is used in preference to the older nomenclature.  相似文献   
2.
1. By using isotopic-dilution techniques it was found that colchicine causes a slight increase in the proalbumin content of liver, from 0.63+/-0.06 to 0.83+/-0.10mg/g of liver, but has no effect on albumin content (0.50+/-0.05mg/g of liver). All the proalbumin and 67% of the albumin is found in vesicles from which they are liberated by detergents. 2. Colchicine inhibits secretion of albumin, decreases the rate of conversion of proalbumin into albumin and decreases the rate of incorporation of l-[1-(14)C]leucine into proalbumin. 3. Balance studies in vivo show that all the (14)C appearing in serum albumin can be accounted for by the flow of (14)C through the proalbumin, in the presence or absence of colchicine. 4. When cycloheximide is given to the rats, 2min after [(14)C]leucine, further synthesis of protein stops. The label in proalbumin disappears and the proalbumin content of the liver falls, so as to account for the albumin appearing in the plasma. This occurs both in the presence and in the absence of colchicine. By contrast, there is little change in liver albumin. Studies with isolated perfused livers are in agreement with the above. Lumicolchicine has no effect on any of these systems at doses at which colchicine exerts its action. 5. These results suggest that biosynthesis and conversion of proalbumin into albumin, and secretion of serum albumin are controlled at each step.  相似文献   
3.

Introduction

Ultrasonography (US) might have an added value to clinical examination in diagnosing early rheumatoid arthritis (RA) and assessing remission of RA. We aimed to clarify the added value of US in RA in these situations performing a systematic review.

Methods

A systematic literature search was performed for RA, US, diagnosis and remission. Methodological quality was assessed; the wide variability in the design of studies prohibited pooling of results.

Results

Six papers on the added value of US diagnosing early RA were found, in which at least bilateral metacarpophalangeal (MCP), wrists and metatarsophalangeal (MTP) joints were scanned. Compared to clinical examination, US was superior with regard to detecting synovitis and predicting progression to persistent arthritis or RA. Eleven papers on assessing remission were identified, in which at least the wrist and the MCP joints of the dominant hand were scanned. Often US detected inflammation in patients clinically in remission, irrespective of the remission criteria used. Power Doppler signs of synovitis predicted X-ray progression and future flare in patients clinically in remission.

Conclusions

US appears to have added value to clinical examination for diagnosing of RA when scanning at least MCP, wrist and MTP joints, and, when evaluating remission of RA, scanning at least wrist and MCP joints of the dominant hand. For both purposes primarily power Doppler US might be used since its results are less equivocal than those of greyscale US.  相似文献   
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5.
ObjectivesTo investigate the association between suicide and area based measures of deprivation and social fragmentation.DesignEcological study.Setting633 parliamentary constituencies of Great Britain as defined in 1991.ResultsMortality from suicide and all other causes increased with increasing Townsend deprivation score, social fragmentation score, and abstention from voting in all age and sex groups. Suicide mortality was most strongly related to social fragmentation, whereas deaths from other causes were more closely associated with Townsend score. Constituencies with absolute increases in social fragmentation and Townsend scores between 1981 and 1991 tended to have greater increases in suicide rates over the same period. The relation between change in social fragmentation and suicide was largely independent of Townsend score, whereas the association with Townsend score was generally reduced after adjustment for social fragmentation.ConclusionsSuicide rates are more strongly associated with measures of social fragmentation than with poverty at a constituency level.

Key messages

  • Place of residence may affect health, and mortality from most common diseases tends to be higher in areas characterised by low socioeconomic position
  • Research dating back over 100 years suggests that social fragmentation may influencesuicide
  • In the 1980s and 1990s, parliamentary constituencies with high levels of social fragmentation had high rates of suicide, independent of deprivation
  • Constituencies with the greatest increases in social fragmentation between 1981 and 1991 also had the greatest increases in suicide rates over the same period
  • Any targeting of suicide prevention may be more effective if aimed at socially fragmented rather than deprived areas
  相似文献   
6.
ObjectivesTo compare the extent to which late 20th century patterns of mortality in London are predicted by contemporary patterns of poverty and by late 19th century patterns of poverty. To test the hypothesis that the pattern of mortality from causes known to be related to deprivation in early life can be better predicted by the distribution of poverty in the late 19th century than by that in the late 20th century.DesignData from Charles Booth''s survey of inner London in 1896 were digitised and matched to contemporary local government wards. Ward level indices of relative poverty were derived from Booth''s survey and the 1991 UK census of population. All deaths which took place within the surveyed area between 1991 and 1995 were identified and assigned to contemporary local government wards. Standardised mortality ratios for various causes of death were calculated for each ward for all ages, under age 65, and over age 65. Simple correlation and partial correlation analysis were used to estimate the contribution of the indices of poverty from 1896 and 1991 in predicting ward level mortality ratios in the early 1990s.SettingInner London.ResultsFor many causes of death in London, measures of deprivation made around 1896 and 1991 both contributed strongly to predicting the current spatial distribution. Contemporary mortality from diseases which are known to be related to deprivation in early life (stomach cancer, stroke, lung cancer) is predicted more strongly by the distribution of poverty in 1896 than that in 1991. In addition, all cause mortality among people aged over 65 was slightly more strongly related to the geography of poverty in the late 19th century than to its contemporary distribution.ConclusionsContemporary patterns of some diseases have their roots in the past. The fundamental relation between spatial patterns of social deprivation and spatial patterns of mortality is so robust that a century of change in inner London has failed to disrupt it.  相似文献   
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8.
The regulation of proline biosynthesis has been examined in callus and cell cultures of the indica-type rice cultivar Khao Dawk Mali 105 (KDML105) in response to a saline treatment (250 mM NaCl) in terms of the expression of Δ1-pyrroline-5-carboxylate reductase (OsP5CR) and members of the gene family encoding the rate-determining enzyme, Δ1-pyrroline-5-carboxylate synthase (designated OsP5CS1 and OsP5CS2). Using friable callus, growth was retarded by treatment with 250 mM NaCl within 4 days, with a significant increase in the expression of OsP5CS2 by 24 h, and a less marked induction in OsP5CS1 and OsP5CR over the same time-course. Cell suspension cultures derived from the friable callus were also treated with 250 mM NaCl and an induction in OsP5CS2 was again observed, although this was not as marked as in the friable callus, and there was no significant change in OsP5CS1 and OsP5CR expression. This is the first report that details the expression of OsP5CS1 and OsP5CS2 in tissue culture and the results show that, in common with whole plants, OsP5CS2 displays a primacy of response to saline treatment. However, this response may require a community of communicating cells, as occurs in callus tissue, rather than cell suspension cultures. This difference has implications both in terms of the biology of signaling in response to increased salinity and in the use of tissue culture to screen for saline-tolerant germplasm.  相似文献   
9.
Objectives To explore whether the apparent impact of income inequality on health, which has been shown for wealthier nations, is replicated worldwide, and whether the impact varies by age.Design Observational study. Setting 126 countries of the world for which complete data on income inequality and mortality by age and sex were available around the year 2002 (including 94.4% of world human population).Data sources Data on mortality were from the World Health Organization and income data were taken from the annual reports of the United Nations Development Programme.Main outcome measures Mortality in 5-year age bands for each sex by income inequality and income level.Results At ages 15-29 and 25-39 variations in income inequality seem more closely correlated with mortality worldwide than do variations in material wealth. This relation is especially strong among the poorest countries in Africa. Mortality is higher for a given level of overall income in more unequal nations.Conclusions Income inequality seems to have an influence worldwide, especially for younger adults. Social inequality seems to have a universal negative impact on health.  相似文献   
10.
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