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61.
The aim of the present study is to assess the possible protective effects of thymol and carvacrol against cisplatin (CP)‐induced nephrotoxicity. A single dose of CP {6 mg/kg, intraperitoneally (i.p.)} injected to male rats revealed significant increases in serum urea, creatinine, and tumor necrosis factor alpha levels. It also increased kidney contents of malondialdehyde and caspase‐3 activity with significant reduction in serum albumin, kidney content of reduced glutathione as well as catalase, and superoxide dismutase activity as compared to that of the control group. In contrast, administration of thymol {20 mg/kg, orally (p.o.)} and/or carvacrol (15 mg/kg, p.o.) for 14 days before CP injection and for 7 days after CP administration restored the kidney function and examined oxidative stress parameters. In conclusion, thymol was more effective nephroprotective than carvacrol. Moreover, a combination of thymol and carvacrol had a synergistic nephroprotective effect that might be attributed to antioxidant, anti‐inflammatory, and antiapoptotic activities.  相似文献   
62.

Background

Breast cancer survivors, particularly those treated with chemotherapy, are at significantly increased risk for long-term cognitive and neurobiologic impairments. These deficits tend to involve skills that are subserved by distributed brain networks. Additionally, neuroimaging studies have shown a diffuse pattern of brain structure changes in chemotherapy-treated breast cancer survivors that might impact large-scale brain networks.

Methods

We therefore applied graph theoretical analysis to compare the gray matter structural networks of female breast cancer survivors with a history of chemotherapy treatment and healthy age and education matched female controls.

Results

Results revealed reduced clustering coefficient and small-world index in the brain network of the breast cancer patients across a range of network densities. In addition, the network of the breast cancer group had less highly interactive nodes and reduced degree/centrality in the frontotemporal regions compared to controls, which may help explain the common impairments of memory and executive functioning among these patients.

Conclusions

These results suggest that breast cancer and chemotherapy may decrease regional connectivity as well as global network organization and integration, reducing efficiency of the network. To our knowledge, this is the first report of altered large-scale brain networks associated with breast cancer and chemotherapy.  相似文献   
63.
Higher plant plasma membranes carry receptors of different affinity for the phytotoxin fusicoccin. Reception of fusicoccin involves proteins belonging to the highly conserved 14-3-3 family, but the complete structure of the fusicoccin receptor (FCR) is unknown. Using radiation inactivation analysis, we estimated the molecular masses of low-affinity and high-affinity FCR at 63 +/- 7 and 130 +/- 15 kD, respectively. The dose dependences of receptor inactivation indicate that microsomal specimens contain "silent" FCRs of 420 +/- 90 kD in amounts commensurate with that of the active FCRs. Both low- and high-affinity FCRs are inactivated by hydrolytic enzymes from the outer surface of the plasma membrane, and impairment of protoplast integrity causes an irreversible transition of the low-affinity binding site into the high-affinity one. A scheme is proposed for the organization of different types of FCR in the plasma membrane, implying that the membrane affinity for fusicoccin reflects the interaction between proteins in the FCR complex.  相似文献   
64.
Enhancement of the erythroid maturation in Friend virus-induced leukemic cells has been examined in vitro by the treatment with dimethyl sulfoxide (DMSO). Although the cell growth was inhibited in the medium containing 2% DMSO, many cells remained viable for a week. By the 3rd day of the culture, the cells treated with DMSO became more strongly agglutinated by phytohemagglutinin than the cells incubated without DMSO. Mouse erythrocyte membrane-specific antigens were also detectable at the 4th day. At the 8th day of the culture hemoglobin synthesis was apparently demonstrated in the cells treated with DMSO, which could not be seen in the untreated cells. Maturation or differentiation along the erythroid pathway in Friend leukemic cells by DMSO is discussed on these markers.  相似文献   
65.
We have developed a digital image processing technique based on highpass filtering of microfluorimetric images for selective transmission of fine image details corresponding to mitochondria. This technique enabled the detection of the mitochondrial calcium signals with high selectivity, simultaneously with the cytosolic calcium signal. The validity of this technique was supported in primary cultures of rat brain capillary endothelial cells loaded with X-rhod-1 by the results that (i) inhibition of the mitochondrial Ca2+ uptake by discharging the mitochondrial membrane potential selectively abolished the transient of the highpass filtered signal evoked by ATP, and (ii) CGP-37157, a selective blocker of the mitochondrial Na+/Ca2+ exchanger, increased the peak amplitude of highpass filtered (mitochondrial) Ca2+ transients and caused a sustained plateau. The highpass filtering technique enabled the analysis of the mitochondrial Ca2+ transients in high temporal resolution. We found a uniform and monophasic rise of [Ca2+] in the mitochondrial population of the cell, following the cytosolic [Ca2+] with a delay at onset and peak. The introduced highpass filtering technique is a powerful tool in the high spatial and temporal resolution analysis of mitochondrial calcium transients, and it could be especially important in specimens where genetically targeted probes fail.  相似文献   
66.
A synthesis of 1-(beta-D-ribofuranosyl)-pyridin-2-thiones via reaction of 3-cyanopyridin-2(1H)-thiones with 2,3,5-tri-O-benzoyl-D-ribofuranosyl bromide under basic conditions, followed by hydrolysis with methanolic ammonia is reported.  相似文献   
67.
N3-beta-D-glucopyranosyl, galactopyranosyl and xylopyranosyl 6-methyl-2-methylthiouracil and their 5-bromo derivatives have been synthesized by coupling an alpha-acetobromosugar with the corresponding thiouracil. The new modified thiouridine analogues were evaluated for their inhibitory activity against Human Immunodeficiency Virus (HIV) replication in MT-4 cells as well as for their cytotoxicity.  相似文献   
68.

Background

Point of care testing (PoCT) may be a useful adjunct in the management of chronic conditions in general practice (GP). The provision of pathology test results at the time of the consultation could lead to enhanced clinical management, better health outcomes, greater convenience and satisfaction for patients and general practitioners (GPs), and savings in costs and time. It could also result in inappropriate testing, increased consultations and poor health outcomes resulting from inaccurate results. Currently there are very few randomised controlled trials (RCTs) in GP that have investigated these aspects of PoCT.

Design/Methods

The Point of Care Testing in General Practice Trial (PoCT Trial) was an Australian Government funded multi-centre, cluster randomised controlled trial to determine the safety, clinical effectiveness, cost effectiveness and satisfaction of PoCT in a GP setting. The PoCT Trial covered an 18 month period with the intervention consisting of the use of PoCT for seven tests used in the management of patients with diabetes, hyperlipidaemia and patients on anticoagulant therapy. The primary outcome measure was the proportion of patients within target range, a measure of therapeutic control. In addition, the PoCT Trial investigated the safety of PoCT, impact of PoCT on patient compliance to medication, stakeholder satisfaction, cost effectiveness of PoCT versus laboratory testing, and influence of geographic location.

Discussion

The paper provides an overview of the Trial Design, the rationale for the research methodology chosen and how the Trial was implemented in a GP environment. The evaluation protocol and data collection processes took into account the large number of patients, the broad range of practice types distributed over a large geographic area, and the inclusion of pathology test results from multiple pathology laboratories. The evaluation protocol developed reflects the complexity of the Trial setting, the Trial Design and the approach taken within the funding provided. The PoCT Trial is regarded as a pragmatic RCT, evaluating the effectiveness of implementing PoCT in GP and every effort was made to ensure that, in these circumstances, internal and external validity was maintained.

Trial Registration

12612605000272695  相似文献   
69.
70.
栖息地丧失和捕猎导致许多大型狐蝠濒危。尽管在东半球热带地区已经禁止捕猎和采伐,狐蝠的数量仍然在下降。既能维护当地居民利益又能保护狐蝠的折衷对策是生态旅游。然而,人类活动对狐蝠的影响还是未知的。菲律宾Boracay和Mambukal都是旅游区,前者游人少而稳定,后者游人密集且变异较大。我们用非损伤取样法研究了这两个旅游区三种狐蝠的生理紧张情况。在Mambukal,当狐蝠外出采食时,采集狐蝠的粪样,实验室分析粪样肾上腺皮质激素代谢物(GCM)浓度。我们观察记录了紧张反应等一些行为,同时记录了环境因素和人类活动情况。结果表明狐蝠已经习惯了游人的活动,表现在:(1)我们发现两个旅游区游人数量和活动强度差异显著,但是两地狐蝠的行为没有明显的差异;并且在有干扰和无干扰的日期之间,狐蝠的行为也无显著差异;两个旅游区的狐蝠行为表达一致;(2)各种行为与测定的粪样GCM浓度都不相关;(3)尽管在不同研究地点人类活动变异很大,我们发现人类活动并未影响粪样GCM浓度;不过,栖息在狐蝠群中心位置个体的粪样GCM浓度低于在群外围个体的GCM浓度;(4)一些环境因素(如干扰以及与栖息群的距离)影响狐蝠一些行为(如不安、身体护理和哈欠)的表达。如果干扰没有造成狐蝠紧张反应,那么生态旅游将不失为一种保护濒危狐蝠栖息地的理想方案。不过,我们还应认识到,人类干扰对狐蝠行为的影响可能比本研究观察到的更加复杂。因此,对于保护濒危狐蝠,时刻保持干扰最小是最好的选择。  相似文献   
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