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71.
72.
Integrating economic costs into conservation planning 总被引:3,自引:0,他引:3
Naidoo R Balmford A Ferraro PJ Polasky S Ricketts TH Rouget M 《Trends in ecology & evolution》2006,21(12):681-687
Recent studies that incorporate the spatial distributions of biological benefits and economic costs in conservation planning have shown that limited budgets can achieve substantially larger biological gains than when planning ignores costs. Despite concern from donors about the effectiveness of conservation interventions, these increases in efficiency from incorporating costs into planning have not yet been widely recognized. Here, we focus on what these costs are, why they are important to consider, how they can be quantified and the benefits of their inclusion in priority setting. The most recent work in the field has examined the degree to which dynamics and threat affect the outcomes of conservation planning. We assess how costs fit into this new framework and consider prospects for integrating them into conservation planning. 相似文献
73.
Gokalp O Uz E Cicek E Yilmaz HR Ozer MK Altunbas A Ozcelik N 《Molecular and cellular biochemistry》2006,290(1-2):55-59
Isoniazid (INH) still remains a first-line drug both for treatment and prophylaxis of tuberculosis, but various organs toxicity
frequently develops in patients receiving this drug. We aimed to investigate possible toxic effects of INH on rat red blood
cells (RBCs), and to elucidate whether Caffeic acid phenethyl ester (CAPE) prevents a possible toxic effect of INH. Experimental
groups were designed as follows: control group, INH group, INH + CAPE group. Compared with the control, the INH caused a significant
increase in superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels, and a decrease in glutathione peroxidase
(GSH-Px) and catalase (CAT), which are recently used to monitor the development and extent of damage due to oxidative stresses.
CAPE administration to INH group ameliorated above changes due to INH. 相似文献
74.
Cigremis Y Parlakpinar H Polat A Colak C Ozturk F Sahna E Ermis N Acet A 《Molecular and cellular biochemistry》2006,285(1-2):149-154
Doxorubicin (DOX) is a broad-spectrum anthracycline antibiotic that has cardiotoxicity as a major side effect. One mechanism of this toxicity is believed to involve the reactive oxygen radical species (ROS); these agents likely account for the pathophysiology of DOX-induced cardiomyopathy. Aminoguanidine (AG) is an effective antioxidant and free radical scavenger which has long been known to protect against ROS formation. We investigated the effects of AG on DOX-induced changes in thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) content. The rats were divided into four groups:1) Control; 2) DOX group; injected intraperitoneally (i.p.) with DOX 20 mg/kg in a single dose 3) AG-treated group; injected i.p. in single dose of 20 mg/kg DOX plus 100 mg/kg AG 1 h before the DOX for 3 days, 4) AG group; injected i.p. with AG 100 mg/kg for 3 days. DOX administration to control rats increased TBARS and decreased GSH levels. AG administration before DOX injection caused significant decrease in TBARS and increase in GSH levels in the heart tissue when compared with DOX only. Morphological changes, including severe myocardial fibrosis and inflammatory cell infiltration were clearly observed in the DOX-treated heart. AG reversed the DOX-induced heart damage. Therefore AG could protect the heart tissue against free radical injury. The application of AG during cancer chemotherapy may attenuate tissue damage and improve the therapeutic index of DOX. 相似文献
75.
76.
Bekele Afessa MD 《BMC pulmonary medicine》2001,1(1):1-7
Background
A prospective observational study was done to describe nonbacterial pulmonary complications in hospitalized patients with human immunodeficiency virus (HIV) infection. 相似文献77.
78.
Ru Ping Lee David Wang Nien Tsung Lin Prof. Hsing I. Chen MD PhD 《Journal of biomedical science》2002,9(6):613-621
Endotoxin shock is a major cause of death in patients with septicemia. Endotoxin induces nitric oxide (NO) production and causes tissue damage. In addition, the release of oxygen free radicals has also been observed in endotoxin shock and was found to be responsible for the occurrence of multiple organ failure. The purpose of the present study was to evaluate suitable indicators for early and late stages of endotoxin shock. The experiments were designed to induce endotoxin shock in conscious rats by means of anEscherichia coli lipopolysaccharide (LPS) injection. Arterial pressure (AP) and heart rate (HR) were continuously monitored for 72 h after LPS administration. The maximal decrease in AP and increase in HR and nitrate/nitrite level occurred at 9–12 h following LPS administration. The white blood cell (WBC) count had decreased at 3 h. Hydroxyl radical (methyl guanidine, MG) decreased rapidly after LPS administration. Plasma levels of blood urea nitrogen (BUN), creatinine (Cr), lactic dehydrogenase (LDH), creatine phosphokinase (CPK), and glutamic oxaloacetic transaminase increased before the rise of amylase. Our results suggest that changes in AP, HR, WBC, free radicals, and chemical substances (BUN, Cr) can possibly serve as approximate indicators for the early stage of endotoxin shock. Severe multiple organ damage may be caused by amylase release in the late stage of endotoxin shock. 相似文献
79.
80.
Over the last decade, the genetic basis for CBAVD has been identified by its association with CFTR gene mutations, and CBAVD is now generally considered to be a mild or incomplete form of CF. In this review, the author summarizes the main results of compilation of CFTR gene analysis conducted in French laboratories for 3,923 patients with CF and 800 males with CABVD. The degree of clinical expression can be affected by several variables, including the molecular mechanisms by which the various CFTR mutations impair or disrupt the function of the CFTR chloride channel. Phenotypic expression of CFTR mutational genotypes varies from severe, progressive pulmonary disease with pancreatic insufficiency (CF-PI), to mild pulmonary disease with pancreatic sufficiency (PS) or singleorgan forms of “CFTR-opathies”. In CF, a total of 310 different CFTR mutations accounting for 94% of 7,846 CF alleles have generated almost 500 different genotypes, comprising 2 severe mutations in 88% of cases (CF-PI), one severe mutation in trans to a mild mutation in 11% (CF-PS), and 2 mild mutations in 1% of identified genotypes. In CBAVD, 137 mutations scattered over the whole gene were identified in 60% of 1,600 CBAVD alleles during the study. Among the 150 characterized mutational CFTR genotypes, compound heterozygosity was the rule, and the most frequent CBAVD combinations were ΔF508/5T (35%), ΔF508/other mutation (30%, including ΔF508/R117H-7T: 5,6%), and 5T/other mutation (17%). No combination of two severe mutations was found in CBAVD (0%); by contrast with the CF population, 88% of genotypes identified in CBAVD comprised a severe mutation in trans to a mild mutation, and 12% consisted of 2 mild mutations. A total of 22 genotypes were shared by both CF and CBAVD. The role of the 5T allele as a splicing variant with variable, incomplete disease penetrance in CBAVD is reviewed. Other haplotype backgrounds, such as the TG12 sequence and the M470V polymorphism, may influence CFTR splicing and/or function. This study confirms the high molecular heterogeneity of CFTR mutations in CBAVD and emphasizes the importance of extensive CFTR analysis in these patients. Longterm follow-up studies of CBAVD patients are necessary in order to predict the phenotypic consequences of numerous CFTR mutational genotypes. 相似文献