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121.
高照  李法琦 《生命科学》2010,(8):772-777
松弛素是一类新近发现可作用于心血管的肽类激素,参与心血管系统的生理和病理过程。大量实验研究显示松弛素有扩血管、改善心血管重塑及调节炎症反应的心血管保护作用,也有利于改善高凝状态和胰岛素抵抗。松弛素作用广泛,可与松弛素受体或糖皮质激素受体结合,但其受体后的确切机制以及不同生理和病理状态对松弛素的调控还需进一步基础研究阐明。在从实验室到临床应用转化的初期临床试验中可观察到,人重组松弛素治疗急慢性心力衰竭安全性好,可改善症状、血流动力学指标及近期预后,为Ⅲ期临床试验奠定了基础,其临床应用前景令人期待。  相似文献   
122.
回顾性分析体外受精-胚胎移植(IVF-ET)的686个周期,比较多原核受精组(348例)和非多原核受精组(338例)两组的一般资料、HCG日雌孕激素、获卵数、授精密度及活力、受精率、卵裂率、妊娠率.结果显示两组HCG日雌孕激素、获卵数、成熟卵率、受精率、卵裂率、妊娠率之间有显著差异(P0.05),授精密度、受精活力之间无差异.表明HCG日雌孕激素较高,获卵数多及未成熟和过熟卵子比例高,预示着发生多原核受精的可能性大,而多原核受精的发生可能有较好的临床结局.  相似文献   
123.
Bacillus cereus strains from cases of severe or lethal systemic infections, including respiratory symptoms cases, were analyzed using multilocus sequence typing scheme of B. cereus MLST database. The isolates were evenly distributed between the two main clades, and 60% of them had allele profiles new to the database. Half of the collection's strains clustered in a lineage neighboring Bacillus anthracis phylogenetic origin. Strains from lethal cases with respiratory symptoms were allocated in both main clades. This is the first report of strains causing respiratory symptoms to be identified as genetically distant from B. anthracis. The phylogenetic location of the presented here strains was compared with all previously submitted to the database isolates from systemic infections, and were found to appear in the same clusters where clinical isolates from other studies had been assigned. It seems that the pathogenic strains are forming clusters on the phylogenetic tree.  相似文献   
124.
Edwards SJ 《Bioethics》2006,20(2):77-91
In this paper, I support the claim that placing certain restrictions on public access to possible new treatments is morally problematic under some exceptional circumstances. Very ill patients may find that all available standard treatments are unacceptable, either because they are ineffective or have serious adverse effects, and these patients may understandably be desperate to try something new even if this means stepping into the unknown. Faced with certain death, it is rational to want to try something new and to chance a dire outcome. Restricting possible new treatments to research trials may put these treatments scientifically, geographically or economically out of reach of these patients. For those who can get access, research restrictions could weaken, though not necessarily eliminate, the value of consent participants of such trials are able to give. Some participants may therefore be exploited for scientific purposes in the name of public interest. There are nonetheless compelling reasons for keeping some restrictive regulation in this area.  相似文献   
125.
In Japan during 1996-2004, 21 actinomycete strains that have madurose as the diagnostic cell-wall sugar and show true branching in their substrate and aerial mycelia were isolated from sputa or bronchoalveolar lavage (BAL) fluid of patients with pulmonary infections or who were suspected of having related infections. Chemotaxonomic studies showed that all the isolates belong to the genus Actinomadura. Among them, six and seven strains were classified respectively into clusters of Actinomadura nitritigenes and Actinomadura cremea based on 16S rDNA analyses because their 16S rDNA similarities to those respective species were greater than 99.5%. To our knowledge, this is first report that strains of above two species were isolated from clinical specimens. Neither Actinomadura madurae nor Actinomadura pelletieri strain was isolated, and one new species, Actinomadura chibensis, was proposed; the remaining seven strains were not assigned into any known species, suggesting the presence of another new Actinomadura species.  相似文献   
126.
The use of in vitro prepared biosynthetic grafts can considerably improve the patient’s quality of life. This work reports on the use of an autologous graft prepared from a patient’s preputial cells cultivated on biodegradable polymeric membrane. Coladerm membrane is based on the chemically modified polyelectrolyte complex of atelocollagen and hyaluronan. The graft was used to cover a defect in the mouth cavity base and tongue after reconstruction surgery performed at this site in the past. The presented clinical case showed that the autologous biosynthetic graft prepared from foreskin cells can be successfully used for covering of medium-size defects in mouth cavity base resulting in the regeneration of target mouth structures with significant improvement of patient’s quality of life.  相似文献   
127.
We investigated the correlation between the SOD activity of Helicobacter pylori (H. pylori) and gastroduodenal diseases and the characteristics of strains exposed to oxidative stress. Two sequenced strains, 26695 and J99, and clinical isolates from 156 Japanese patients with gastroduodenal diseases such as gastric cancer (n= 59) and non-cancer (n= 97) were used. SOD activities of all 158 isolates were measured and were divided into three groups: high-SOD activity (>0.22, n= 2), moderate-SOD activity (0.15≦≦0.22, n= 16) and low-SOD activity (<0.15, n= 140). Expressions of H. pylori Fe-SOD were examined by western blotting with anti-H. pylori Fe-SOD antibody prepared inhouse, and the profiles of Fe-SOD activity were investigated by zymogram with activity staining in native-PAGE. The characteristics of strains from high-SOD and low-SOD groups were examined under oxidative stress by paraquat. The average of H. pylori SOD activity was significantly higher in the cancer group than in the non-cancer group (P < 0.05). However, irrespective of SOD activity level, the amount of Fe-SOD expressed was variable among individual strains. Zymogram revealed a single band in moderate-SOD and low-SOD strains, but multiple bands in high-SOD strains were observed. These bands were confirmed as H. pylori Fe-SOD. Under oxidative stress with paraquat, low-SOD strains were drastically eliminated without inducible SOD activity; however, high-SOD strains were still viable with increased SOD activity. This study is the first to exhibit the characteristics of high-SOD activity strains representing multiple bands in zymograms and the correlation between H. pylori SOD activity and gastric cancer.  相似文献   
128.
doi: 10.1111/j.1741‐2358.2012.00626.x Evaluation of the efficacy of two mouthrinses formulated for the relief of xerostomia of diverse origin in adult subjects Objective: To evaluate the efficacy of two new mouthrinses in the reduction of xerostomía‐associated symptomatology. Background: Xerostomia is a common chronic health condition that affects a great number of adults and significantly deteriorates quality of life, such that treatment is necessary. Materials and methods: Sixty‐seven adult subjects of both sexes presenting xerostomia of diverse origin were selected. Mouthrinses were tested using a double‐blind, randomized, cross‐over clinical trial with an intervining wash out period. Results: The 100% of subjects presented sensation of dry mouth, and 86% stated sensation of thick saliva. Burning tongue sensation, need to drink liquids to swallow and the sensation of swallowing difficulty were recorded in more than 50% of the patients. The most frequent pathologies in the sample were depression, arthritis, and arterial hypertension. Results of the clinical tests showed that mouthrinse 1 relieves sensation of dry mouth, need to drink liquids, and swallowing difficulty. In contrast, mouthrinse 2 relieves only latter two symptoms. Both rinses were more effective in relieving xerostomía‐associated symptomatology in patients taking 3 or more medicines simultaneously. Conclusion: Both mouthrinses were effective in relieving various xerostomia symptoms, could be distributed at a low cost, thereby improving the quality of life of population affected.  相似文献   
129.
The acquired pellicle is a tenacious organic layer covering the surface of teeth, protecting the underlying dental hard tissues. Lipids account for about one quarter of the pellicle's dry weight and are assumed to be of considerable importance for their protective properties. Nevertheless, only preliminary information is available about the nature of lipids in the pellicle. Gas chromatography coupled with electron impact ionization mass spectrometry was used to establish a convenient analytical protocol in order to obtain a qualitative and quantitative characterization of a wide range of FAs (C(12)-C(22)). In situ biofilm formation was performed on bovine enamel slabs mounted on individual splints carried by 10 subjects. A modified Folch extraction procedure was adopted to extract the lipids from the detached pellicle, followed by transesterification to fatty acid methyl esters using methanol and concentrated hydrochloric acid. Tridecanoic and nonadecanoic acid were used as internal standards suitable and reliable for robust, precise and accurate measurements. The present study demonstrates, for the first time, a procedure based on a combination of innovative specimen generation and convenient sample preparation with sensitive GC-MS analysis for the determination of the fatty acid profile of the initial oral biofilm.  相似文献   
130.
Peroxisome proliferator-activated receptor γ (PPAR-γ) is a key regulator of fatty acid metabolism, promoting its storage in adipose tissue and reducing circulating concentrations of free fatty acids. Activation of PPAR-γ has favorable effects on measures of adipocyte function, insulin sensitivity, lipoprotein metabolism, and vascular structure and function. Despite these effects, clinical trials of thiazolidinedione PPAR-γ activators have not provided conclusive evidence that they reduce cardiovascular morbidity and mortality. The apparent disparity between effects on laboratory measurements and clinical outcomes may be related to limitations of clinical trials, adverse effects of PPAR-γ activation, or off-target effects of thiazolidinedione agents. This review addresses these issues from a clinician's perspective and highlights several ongoing clinical trials that may help to clarify the therapeutic role of PPAR-γ activators in cardiovascular disease.  相似文献   
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