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91.
The present study is based on the measurement of concentrations of selected trace metals (Fe, Zn, Cu, Co, Mn, Ni, Cr, Cd and Pb) and thyroid hormones (TSH and T4) in blood serum of hypothyroid and hyperthyroid patients in comparison with healthy donors/controls in order to establish the imbalances of the trace metals in diseased subjects. The serum samples were digested in HNO3-HClO4 mixture and quantification of the metals was performed by flame atomic absorption spectrometry. Average levels of Fe, Ni, Cu, Cr, Pb and TSH were found to be significantly higher (p < 0.05) in the serum of hypothyroid patients compared with other donor categories, while mean concentrations of Mn, Cd and T4 were significantly elevated in the serum of hyperthyroid patients compared with other donor groups (p < 0.05). The correlation pattern of trace metals in the serum of patient groups revealed significantly different mutual associations compared with the controls. PCA and CA pointed out the interferences of the toxic metals with essential metals in the serum of both patient groups compared with the controls. Most of the metals exhibited noticeable disparities in their concentrations based on gender, food habits and tobacco use for all donor groups. Thus, the pathogenesis of thyroid diseases is significantly affecting the essential trace and toxic metals balance in both patients groups.  相似文献   
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 The long-term conditioning effects of physical training on cardiorespiratory interaction in 11 young healthy males were studied. Significant increases in maximum oxygen uptake (V˙O2max)(P<0.05) and decreases in heart rate (P<0.05) were achieved in all subjects following a 6-week training programme consisting of cycling for 25min each day at a work level that increased heart rate to 85% of maximum. Heart rate variability, measured as the differences between the maximum and minimum R–R interval in a respiratory cycle, increased in nine of the subjects and decreased in two. The respiratory-cycle-related high-frequency peak in the power spectral plot of R–R variability also showed significant increases in the same nine subjects and decreases in two. The latter result was similar after normalisation of the data for changes in heart rate by calculating the common coefficient of variance (CCV=HFR–R×<∮∮), where HF is the high-frequency component of the power spectral plots, using a further measure of vagal tone it was shown that, for all subjects, the R–R interval change in response to isometric contractions of the arm flexors in one respiratory cycle were significantly greater after training. These data suggest that cardiac vagal tone is increased by aerobic training for all subjects and that this is accompanied by a respiratory sinus arrhythmia (RSA) in most, but may be associated with a decrease in RSA in subjects with a very low (< 50 beats⋅min-1 heart rate. Accepted: 23 April 1996  相似文献   
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Asthma is a chronic disease due to inflammation of the airways of lungs that is clinically characterized by variable symptoms including wheezing, coughing and shortness of breath. Angiotensin I-converting enzyme (ACE) plays a major role in fibrous tissue formation and is highly expressed in lungs. The main aim of this research work was to study the role of ACE insertion/deletion (I/D) polymorphism, rs4646994, in asthma in Pakistani patients. A total of 854 subjects, including 333 asthma patients and 521 ethnically matched controls, were studied. The ACE (I/D) polymorphism was genotyped using polymerase chain reaction (PCR). Chi-square, Fisher’s exact and Hardy–Weinberg equilibrium tests were used to compare groups. Homozygous insertion genotype II (p<0.0001, OR=3.38) and insertion allele (I) was significantly more frequent in Pakistani asthmatics than in healthy controls (p=0.0007, OR=1.40). The ID genotype (p<0.0001, OR=0.43) and the deletion allele (D) were associated with protection of disease in Pakistani patients (p=0.0007, OR=0.71). These data suggest the involvement of ACE I/D polymorphism in asthma risk in the Pakistani population. This marker may be an important indication in the molecular mechanism of asthma and can become a useful tool in risk assessment and help in designing strategy to combat disease.  相似文献   
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The White‐headed Vulture Trigonoceps occipitalis (WhV) is uncommon and largely restricted to protected areas across its range in sub‐Saharan Africa. We used the World Database on Protected Areas to identify protected areas (PAs) likely to contain White‐headed Vultures. Vulture occurrence on road transects in Southern, East, and West Africa was adjusted to nests per km2 using data from areas with known numbers of nests and corresponding road transect data. Nest density was used to calculate the number of WhV nests within identified PAs and from there extrapolated to estimate the global population. Across a fragmented range, 400 PAs are estimated to contain 1893 WhV nests. Eastern Africa is estimated to contain 721 nests, Central Africa 548 nests, Southern Africa 468 nests, and West Africa 156 nests. Including immature and nonbreeding birds, and accounting for data deficient PAs, the estimated global population is 5475 ‐ 5493 birds. The identified distribution highlights are alarming: over 78% (n = 313) of identified PAs contain fewer than five nests. A further 17% (n = 68) of PAs contain 5 ‐ 20 nests and 4% (n = 14) of identified PAs are estimated to contain >20 nests. Just 1% (n = 5) of PAs are estimated to contain >40 nests; none is located in West Africa. Whilst ranging behavior of WhVs is currently unknown, 35% of PAs large enough to hold >20 nests are isolated by more than 100 km from other PAs. Spatially discrete and unpredictable mortality events such as poisoning pose major threats to small localized vulture populations and will accelerate ongoing local extinctions. Apart from reducing the threat of poisoning events, conservation actions promoting linkages between protected areas should be pursued. Identifying potential areas for assisted re‐establishment via translocation offers the potential to expand the range of this species and alleviate risk.  相似文献   
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Background

Erythema Nodosum Leprosum (ENL) is a serious complication of leprosy. It is normally treated with high dose steroids, but its recurrent nature leads to prolonged steroid usage and associated side effects. There is little evidence on the efficacy of alternative treatments for ENL, especially for patients who have become steroid resistant or have steroid side effects. These two pilot studies compare the efficacy and side effect profile of ciclosporin plus prednisolone against prednisolone alone in the treatment of patients with either new ENL or chronic and recurrent ENL.

Methods and Results

Thirteen patients with new ENL and twenty patients with chronic ENL were recruited into two double-blinded randomised controlled trials. Patients were randomised to receive ciclosporin and prednisolone or prednisolone treatment only. Patients with acute ENL had a delay of 16 weeks in the occurrence of ENL flare-up episode, with less severe flare-ups and decreased requirements for additional prednisolone. Patients with chronic ENL on ciclosporin had the first episode of ENL flare-up 4 weeks earlier than those on prednisolone, as well as more severe ENL flare-ups requiring 2.5 times more additional prednisolone. Adverse events attributable to prednisolone were more common that those attributable to ciclosporin.

Conclusions

This is the first clinical trial on ENL management set in the African context, and also the first trial in leprosy to use patients’ assessment of outcomes. Patients on ciclosporin showed promising results in the management of acute ENL in this small pilot study. But ciclosporin, did not appear to have a significant steroid–sparing effects in patients with chronic ENL, which may have been due to the prolonged use of steroids in these patients in combination with a too rapid decrease of steroids in patients given ciclosporin. Further research is needed to determine whether the promising results of ciclosporin in acute ENL can be reproduced on a larger scale.  相似文献   
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In rat liver the asialoglycoprotein receptor is composed of three polypeptides, RHL-1, RHL-2 and RHL-3 [6]. In rat testis and spermatozoa a galactosyl receptor (RTG-r) which is immunologically related to RHL-2/3 has been described [7]. We now report that in addition to its presence in the rat, an antigenic species of 54 kDa related to RHL-2/3 is present on rabbit, human, pig and mouse spermatozoa. Purified rabbit testis galactosyl receptor (RbTG-r) consists of two major proteins of 54 and 49 kDa, while purified rabbit liver galactose lectin consists of two major proteins of 43 and 40 kDa. In an ELISA the purified rabbit testis galactosyl receptor was shown to bind biotinylated heat solubilized rabbit zonae, while the purified liver galactose lectin did not. We conclude that one of the mammalian sperm's zona binding proteins is a galactose lectin of 54 kDa related to rat liver RHL-2/3.  相似文献   
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