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排序方式: 共有1359条查询结果,搜索用时 15 毫秒
1.
Epidemiology of severe trauma among status Aboriginal Canadians: a population-based study 总被引:3,自引:1,他引:2
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A comparison of the prevalence of rheumatoid arthritis and other rheumatic diseases amongst Pakistanis living in England and Pakistan 总被引:3,自引:0,他引:3
The impact of environmental factors on the causation of rheumatoid
arthritis (RA) is thought to be considerable. We explored this by comparing
the prevalence of RA amongst Pakistanis living in England, where it is
relatively high amongst ethnic English, and in Pakistan. The frequency of
other rheumatic diseases was also compared. Information on 2056 adult
Pakistanis in England and 4232 in Pakistan was obtained by house-to-house
surveys using identical protocols. Positive respondents were examined by
the same two clinicians in both countries. Rheumatic complaints increased
with age and were more common in females in both communities. The
standardized morbidity ratio (SMR) (95% CI) of RA in England was 2.1
(1.1-3.1) compared with Pakistan, a difference that was entirely
attributable to females. The SMR (95% CI) for women was 3.0 (0.4-5.6) and
for men 0.86 (-0.84 to 2.56). In Pakistan, there was a trend to more
reporting of some but not all rheumatic complaints amongst the affluent
segment of the population. This was increasingly apparent amongst those
resident in England and the possibility of an impact of easier
ascertainment amongst the more educated cannot be discounted. Low back pain
was significantly more common in England. Furthermore, the colder climate
was frequently invoked as a cause of more symptoms in England. Thus,
several factors may have influenced the observation that RA is more common
amongst Pakistanis in England compared with Pakistan. An environmental
factor cannot be excluded. However, the frequency of non-specific
musculoskeletal pain was similar. The regions of Pakistan from which the
two populations were derived were also different and immunogenetic
heterogeneity might also have contributed to the difference in RA
prevalence.
相似文献
4.
Thirty rhizobacteria isolated from maize grown in Pakistani and Indonesian soils were evaluated for their morphological characteristics, nitrogen fixation, P-solubilization, indole acetic acid (IAA) and siderophores production. Nitrogenase activity was detected in nineteen isolates ranging from 21.8-3624 n moles C2H4 produced/h/mg protein. Most of the isolates produced IAA, ten were capable of siderophore production while four were P-solubilizers. Ultrastructural studies of Pseudomonas sp. F14 indicated characteristic rhizospheric colonization within 48 h that was observed to change considerably with the passage of time from few bacteria to micro colonies. Random amplified polymorphic DNA (RAPD) analysis of 30 bacterial strains using 30 oligonucleotide primers resulted in considerable level of genetic diversity, with genetic distance ranging from 2-16%. Indonesian isolates were found to be more diverse as compared to Pakistani isolates. The characterization and screening of rhizobacteria of maize rhizosphere has helped in selection of isolates F7, LS-1, 3.1.1.C, F2, F3 and F13 as superior strains for use as bioinoculant. Moreover isolate F14 identified, as Pseudomonas fulgida by partial 16S rRNA sequence analysis is a novel strain regarding its tremendous potentials for inoculum production to enhance the yield of maize. 相似文献
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6.
Julio C Delgado Ahasan Hameed Juan J Yunis Kailash Bhol Adriana I Rojas Simeen B Rehman Ashfaq A Khan Manzoor Ahmad Chester A Alper A.Razzzaque Ahmed Edmond J Yunis 《Human immunology》1997,57(2):110-119
ABSTRACT: Pemphigus vulgaris (PV) is an autoimmune disease of the skin and mucous membranes characterized by an autoantibody response against an epidermal cadherin. We performed high resolution HLA class II typing in 19 patients with PV from Rawalpindi, Pakistan and 19 non-Jewish European PV patients from Boston by sequence-specific oligonucleotide probe hybridization. The results were compared with two separate ethnically matched control populations. We found that PV patients from Pakistan had significantly increased frequencies of DRB1*1404 ( p = 0.01), DQA1*0101 ( p = 0.02), and DQB1*0503 ( p = 0.01). Among the patients of non-Jewish European ancestry, DRB1*1401 ( p < 10−6), DQA1*0101 ( p < 10−5) and DQB1*0503 ( p < 10−6), were increased in PV patients. Formal linkage analysis between the major histocompatibility complex and the PV antibody was performed in 67 relatives of the 19 Pakistani patients. The results showed strong evidence for linkage of HLA-DRB1*1404, DQA1*0101, DQB1*0503, with the presence of PV antibody in relatives’ families with a significant logarithm of the odds score of 6.06. Based on the three dimensional structure of class II molecules, we propose that HLA-DQA1*0101 and DQB1*0503, encode a negatively charged P9 peptide binding pocket of the DQ molecule and are significantly associated with susceptibility to PV in non-Jewish populations. 相似文献
7.
[31P]-Nuclear magnetic resonance (NMR) in vivo spectra ofEchinococcus multilocularis cysts growing subcutaneously inMeriones unguiculatus showed prominent signals due to phosphomonoesters (PME), phosphodiesters (PDE), inorganic phosphate (Pi) and the , and phosphate groups of adenosine triphosphate (ATP). The internal pH of the parasite cysts was 6.7–6.8. The31P spectra of extracts of these subcutaneous cysts showed peaks identified as glucose-6-phosphate (Glu-6-P), glycerol-3-phosphate (Gly-3-P), phosphorylethanolamine (PE), adenosine-5-monophosphate (5-AMP), nicotinamide adenine dinucleotide phosphate (NADP), phosphorylcholine (PC), Pi, glycerolphosphorylethanolamine (GPE), glycerolphosphorylcholine (GPC), phosphoenolpyruvate (PEP), adenosine diphosphate (ADP), ATP and diphosphodiesters (DPDE). These metabolites were also detected at comparable concentrations in the extracts of intraperitoneally grown cysts. In addition, significantly more phosphocreatine (PCr), probably of host origin, was detected in the subcutaneous cysts than in the intraperitoneal cysts. [1H]-NMR spectra of cyst extracts revealed that parasites grown in the abdominal cavity contained significantly less glucose but significantly more succinate, acetate, alanine and -hydroxybutyrate. Glycogen, creatine, glycine, taurine, betaine, cholines and lactate were present at similar concentrations in cyst material from both locations. 相似文献
8.
Regulation of Ca2+ current in frog ventricular myocytes by the holding potential,c-AMP and frequency 总被引:3,自引:0,他引:3
Vincent J. A. Schouten Martin Morad 《Pflügers Archiv : European journal of physiology》1989,415(1):1-11
The whole-cell patch-clamp technique was used to study the effects of holding potential and frequency on the Ca2+ current in frog ventricular myocytes. INa was blocked by TTX, and ica was activated with depolarizing clamps from different holding potentials. Variation of the holding potential revealed three new effects on ica: (1) At -40 mV iCa declined with a time constant of 15 min, while at -90 mV, this irreversible decline (run down) in iCa did not occur. (2) The decline of iCa at -40 mV was biphasic: run down was preceeded by a slow inactivation with a time constant of 40 s, which was reversible upon returning the holding potential to -90 mV. (3) Increasing the frequency of the clamp pulses from 0.1 to 1 Hz led to a rapid decline of iCa when the holding potential was positive to -60 mV, but at -90 mV had either no effect or increased iCa by 35%, if c-AMP was included in the dialyzing solution. On the other hand, c-AMP did not alter the time course of the run down and the slow inactivation. Replacement of extracellular Ca2+ by Ba2+ markedly slowed iCa kinetics, but did not change the very slow inactivation or the frequency-induced enhancement of iCa. Injection of c-AMP led to a transient increase of iCa. The phosphodiesterase inhibitor theophylline enhanced the amplitude of the transient and slowed its decay. This effect was mimicked by increased frequency. It is concluded that frequency-induced enhancement of iCa is highly dependent on the holding potential, independent of Ca2+, and may involve elevation of the intracellular level of c-AMP via inhibition of phosphodiesterase activity. The new type of very slow inactivation is probably under direct voltage control and independent of Ca2+ and c-AMP. 相似文献
9.
Barbashina V Heller DS Hameed M Albanese E Goldstein M Dashefsky B Dieudonne A Chakraborty R 《Virchows Archiv : an international journal of pathology》2000,436(2):138-139
Smooth-muscle neoplasms are rarely located in the spleen. They have been previously reported in five cases of children with
human immunodeficiency virus (HIV) infection/acquired immunodeficiency syndrome (AIDS). Two cases of children with HIV infection/AIDS
with autopsy and surgical pathology evidence of multiple smooth-muscle neoplasms with splenic involvement are presented. DNA
was extracted from histology slides in both cases for analysis for Epstein Barr (EB) virus. In both cases, the presence of
EB virus was confirmed. This paper documents two additional cases of the unusual phenomenon of splenic involvement by smooth-muscle
neoplasms in the setting of AIDS in childhood and further supports the role of EB virus in the development of these neoplasms.
Received: 27 January 1999 / Accepted: 23 August 1999 相似文献
10.
Norman PJ Carrington CV Byng M Maxwell LD Curran MD Stephens HA Chandanayingyong D Verity DH Hameed K Ramdath DD Vaughan RW 《Genes and immunity》2002,3(2):86-95
Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations. 相似文献