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Background

We aimed to determine the prevalence of pulmonary tuberculosis (TB) amongst the adult population in 2010–2011 in Pakistan.

Method

A nationwide cross-sectional survey with multistage cluster sampling was conducted among adults (≥15 years) in 95 clusters in 2010–2011. All consenting participants were screened for cough and by chest X-ray. Participants with presumptive TB submitted two sputum samples for smear microscopy, culture, and molecular testing if needed. The TB prevalence estimates were adjusted for missing data and the cluster design.

Result

Of 131,329 eligible individuals, 105,913 (81%) participated in the survey, of whom 10,471 (9.9%) were eligible for sputum examination. We found 341 bacteriologically positive TB cases of whom 233 had sputum smear-positive TB. The adjusted prevalence estimates for smear and bacteriologically positive TB were 270/100,000 (95% confidence interval (CI) 217–323), and 398/100,000 (95% CI 333–463), respectively. Only 61% of the diagnosed TB cases screened positive on symptoms (cough >2wks), whereas the other TB cases were detected based on X-ray abnormalities. The TB prevalence increased with age and was 1.8 times higher among men than women. The prevalence-to-notification ratio of smear-positive TB was 3.1 (95% CI 2.5–3.7), was higher among men than women, and increased with age.

Conclusion

Our data suggest that there is under-detection and/or -notification of TB, especially among men and elderly. TB control should be strengthened specifically in these risk groups. X-ray examination should be combined with symptom screening to enhance case detection.  相似文献   
84.
Fish kidneys are sensitive to chemical changes in the freshwater ecosystem because they are directly and constantly exposed to chemicals dissolved in the water. This study evaluated nephrotoxicity in Wallago attu and Cirrhinus mrigala harvested from the Chenab River in an area of industrial and sewage waste disposal. Induced histological alternation data were correlated to the severity of environmental degradation in order to determine whether this biological system can be used as a tool for environmental monitoring programs. Kidneys from two fish species occupying different niches were collected and stored for 24 h in 10% formalin. Control fish were collected upstream of the polluted river area. Specimens were processed using topical histological methods. The major histological alterations observed in both species were renal tubule myxospora, hyperemia, glomerulonephritis, degeneration of renal tubule cells, dilation of glomerular capillaries, presence of pycnotic nuclei in the hematopoietic tissue, epithelial hypertrophy, vacuolization, reduced lumen of renal tubules, and shrinkage of glomeruli. Renal tubular atrophy, degeneration due to extensive degranulation, necrosis of glomeruli, glomerular expansion, absence of Bowman’s space, hypertrophied nucleus, necrosis and hyalinization of the interstitium, clogging of tubules, and regeneration of tubules was also observed. Wallago attu exhibited the maximum incidence of moderate to severe changes and was defined as having the highest “histopathologic alteration index”. These severe alterations were found to be related to environmental degradation, indicating the presence of stressors in freshwater. Control groups showed normal tissue morphology in the kidneys.  相似文献   
85.
Analysis of fish meat using gas chromatography is described. Flavor is the sensation arising from the interplay of the signals of sensing smell, taste and irritating stimuli from food stuff. For human, flavor and nutrition are inseparable. In fish, trace amount of volatile organic compounds (VOCs) are the major compounds to affect consumer’s preference, which are produced during storage and spoilage. In the present study, volatile compounds were extracted by Likens-Nickerson concurrent distillation apparatus from wild and farmed Cirrhina mrigala and Cyprinus carpio. The quantitative and qualitative estimation of volatiles was made by gas chromatography. Wild and farmed fish of different fish sizes were compared for these compounds (appearing in the form of peaks), which were identified from their retention time by comparing with the standards. Fifteen major VOCs were found in these species which included hexadecane, 3-octanol, hexanal, decane, 3-hexene-1-ol, 2-undecanone, 2-heptanone, butanal, 2-nonanone, 1- heptanal, furaldehyde, 3-methyl-1-butanal, trans-3-hexene-1-ol, octanal and decanal. These compounds varied qualitatively and quantitatively in both wild and farmed fish of different fish sizes.  相似文献   
86.
Rabbits and rats were injected two Nonsteroidal anti-inflammatory drugs (aspirin 300 mg/kg or indomethacin 3 mg/kg) intraperitoneally. One hour after injection blood was analyzed for serum electrolytes and osmolality. Administration of both aspirin and indomethacin in rabbits and rats caused increase in serum sodium, potassium, calcium, chloride, magnesium, phosphorus and osmolality. Results suggest the marked similarity in the action of aspirin and indomethacin on electrolytes and osmolality. It is concluded that the ingestion of aspirin and indomethacin can have a major effect on serum electrolytes and osmolality that may influence the interpretation of clinical data in patients taking these drugs.  相似文献   
87.
The leukocyte immunoglobulin-like receptors (LIRs, also known as ILTs, CD85, and LILRs) comprise a family of related immunoregulatory receptors encoded within the leukocyte receptor cluster (LRC) on human chromosome 19. LIRs are transmembrane proteins containing either two or four extracellular immunoglobulin domains, and most family members are expressed predominantly on myeloid cell lineages. Although the inhibitory receptors LIR-1 and LIR-2 are known to bind to a broad range of class I MHC molecules and are thought to play important roles in immune regulation, the majority of LIRs are currently of unknown structure and their ligands remain unidentified. In this study, we describe recombinant production and characterisation of the extracellular portion of LIR-5 (ILT3), a poorly understood inhibitory receptor that transduces tolerising signals to dendritic cells. The two extracellular immunoglobulin domains of LIR-5 were expressed in Escherichia coli to a high level and were found to accumulate in inclusion bodies. Inclusion bodies were purified, solubilised, and receptor then renatured by dilution refolding, with acceptable yields. Size exclusion chromatography and SDS-PAGE analyses confirmed the extracellular portion behaved as a monomer in solution, and purified protein was antibody-reactive. LIR-5 is representative of a subset of LIR receptors that on the basis of structural and sequence comparisons with LIR-1 seem unlikely to bind class I MHC molecules. Successful prokaryotic generation of correctly folded LIR-5 in high levels has implications for production of other LRC receptors and should greatly facilitate attempts to define the structure and ligands of this important regulator of dendritic cell function.  相似文献   
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The genetic factors that contribute to the development of coronary artery disease (CAD) are poorly understood. It is likely that multiple genes that act independently or synergistically contribute to the development of CAD and the outcome. Recently, an insertion/deletion (I/D) polymorphism of the human angiotensin I-converting enzyme (ACE) gene, a major component of the reninangiotensin system (RAS), was identified. The association of the ACE gene D allele with essential hypertension and CAD has been reported in the African-American, Chinese, and Japanese populations. However, other studies have failed to detect such an association. It has been suggested that these inconsistencies may be due to the difference in backgrounds of the population characteristics. In the present study, we investigated the I/D polymorphism of the ACE gene in 103 subjects of both sexes, consisting of 59 normal controls and 44 patients with hypertension. The allele and genotype frequency were significantly different between the hypertensive and control groups (p < 0.01). Among the three ACE I/D variants, the DD genotype was associated with the highest value of the mean systolic blood pressure [SBP] and mean diastolic blood pressure [DBP] (p = < 0.05) in men, but not in women. In the overall population, the mean SBP and DBP was highest in DD subjects, intermediate in I/D subjects, and the least in II subjects  相似文献   
90.
The S-bridged trinuclear complexes composed of heavy d6 metal ions, [RhIII{M(aet)3}2]3+ (M=IrIII(1), RhIII(2); aet = 2-aminoethanethiolate), have been prepared by the reactions of fac(S)-[M(aet)3] with RhCl3 · 3H2O. The complexes were separated into meso (1a, 2a) and rac (1b, 2b) isomers by SP-Sephadex C-25 column chromatography. 1b and 2b were optically resolved by the column chromatographic method and characterized by CD spectroscopy. Crystal structures of 1a, 1b and 2a were determined by X-ray diffraction, and it was found that they consist of linear-type trinuclear structures. The central Rh(III) ion in the present complexes has d6 electronic configuration with the non-degenerated A-type cubic field term, and showed long Rh?M distances, acute S-M-S angles and obtuse Rh-S-M angles. These are in contrast with the complexes having the degenerated T-type cubic field term such as [M{M(aet)3}2]n+ (M=VIII, MoIV and ReIII, M=IrIII, RhIII, n=3 or 4). All the isomers have been comparatively characterized and discussed in solid state and the solution for spectrochemical and electrochemical properties.  相似文献   
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