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991.
Stenosis of trachea's diameter occurs the most often as complications after intubation and tracheotomy. Among the other reasons of narrowing of this organ the following are being named: mechanical injuries, chemical damages, primary and metastasis tumors. The therapy of trachea's stenosis includes both alternative and radical treatments. The radical treatment consists of surgical excision of the narrowed segment followed by reconstruction of trachea (anastomosing of free ends or filling of lost segment with use of auto- or allogenic material). There is no appropriate alloplastic material developed to date, the use of which in reconstructive surgery of large segment trachea defects would bring about positive long-term experimental results. The success of alloplastic material implantation in the reconstruction of large tracheal defects is limited by the fact that the biomechanical characteristics of replaced tissue are distinctly different from synthetic material. The work is devoted to evaluation of complex mechanical characteristic of natural sheep trachea before designing the proper synthetic material for large tracheal defects reconstruction. Various mechanical tests were conducted to study the mechanical behavior of total trachea. Samples of tissue cut out from trachea were also examined. The results revealed strong directional--dependent mechanical properties of trachea. Composite constituents, namely carbon fibers and biocompatible and biostable polysulfone were used to manufacture the implant.  相似文献   
992.
Recent advances in bladder cancer diagnostics   总被引:3,自引:0,他引:3  
Transitional cell carcinoma of the bladder is a significant cause of morbidity and mortality worldwide. The diagnosis of bladder cancer is based on the information provided by cystoscopy, the gold standard, in combination with urinary cytology findings. Many tumor markers have been evaluated for detecting and monitoring of the disease in serum, bladder washes, and urinary specimens. However, none of these biomarkers reported to date has shown sufficient sensitivity and specificity for the detection of the whole spectrum of bladder cancer diseases in routine clinical practice. The advent of high-throughput microarrays is accelerating the identification process of the molecular events characteristic of bladder tumors' phenotype and subsequent clinical behavior. The information provided by these analyses is resulting not only in the identification of novel therapeutic targets for bladder cancer, but also in the development of diagnostic tools. This review summarizes the reports utilizing high-throughput microarrays in bladder cancer and the implications of these analyses in the diagnosis and clinical management of patients with bladder cancer.  相似文献   
993.
Research and redesign are safer than warnings and rules   总被引:1,自引:0,他引:1  
  相似文献   
994.
995.
Five restriction patterns (including a novel one) could be defined by polymerase chain reaction-restriction fragment length polymorphism on the pertussis toxin (PT) promoter region in local veterinary isolates, suggesting that PT gene analysis is a potential molecular marker for Bordetella bronchiseptica detection and typing.  相似文献   
996.
Tau C  Mautalen C  Casco C  Alvarez V  Rubinstein M 《BONE》2004,35(1):210-216
Chronic idiopathic hyperphosphatasia (CIH), or juvenile Paget disease, is a rare disorder characterized by increased bone turnover and progressive enlargement of bones. We report a girl, 6 1/2 years old, with a history of three fractures, short stature, delayed eruption of teeth, and poor hair growth. She had a waddling gait, bone deformities, kyphoscoliosis, hyperlordosis, genu valgum and curvature of her limbs. She also had progressive hearing loss but other cranial nerves were unaffected. Laboratory studies indicated high bone turnover: serum alkaline phosphatase: 4047 IU/l (normal value: 150-550), urinary hydroxyproline: 1205 mg/g creatinine (n.v.: 60-160), and urinary CrossLaps: 4360 microg/mmol creatinine (n.v.: 450-2100). Radiographs demonstrated generalized skeletal involvement with osteoectasia (expansion) of long bones, diffuse sclerosis, cotton wool appearance of the skull, absence of mastoid pneumatization, and crushed dorsal and lumbar vertebrae. Iliac crest biopsy was compatible with CIH. Cyclical intravenous pamidronate (1 mg/kg/day during 3 h, 3 consecutive days at 2- to 3-month intervals) was administered during 2 years with oral calcium 500 mg and vitamin D 1000 IU/day. Oral pamidronate was added after 11 months of i.v. therapy. Treatment-induced remarkable clinical and radiographic improvement with normalization of bone markers of osteoblastic and osteoclastic activity, including bone alkaline phosphatase, urinary hydroxyproline, and urinary CrossLaps.  相似文献   
997.
The aim of the study was to meet the opinions of NHs' residents about the meals quality and nutrition system, with special consideration of meal ambience in canteens (appearance, atmosphere, etc.). Besides, other information about residents was collected: their self-perceived health status, psychical condition, physical activity, appetite and nutritional habits. Most of the subjects were single women, mainly with medium/technical education level, living in NHs over 3 years. Most of the NHs' residents evaluated their health status as average or bad, independently of the age or gender. Every second person indicated that health, loneliness and the feeling of isolation in their homes were the main reasons for coming to NH. Every third person still felt the loneliness or depression after staying in NH. The physical and intellectual activity of elderly depended on self-perceived health status. Over half of the subjects assessed their appetite as good, and said that their body mass was stable during staying in NH. The statistically significant relationship was found between the self-evaluated weight change and both age and gender. Additionally, the relationship was observed between psychical condition of residents and their appetite as also between the psychical condition and weight change during living in NH. The majority of the subjects (85%) said that they liked the canteen appearance, and they did not want to change anything in it. More women than men thought that canteens were spacious, clean and furnished with good taste, and those differences were significant. Part of studied population (25%) had some reservations about the atmosphere in canteen during the meals, mostly because of too much noise. In the opinions of most of the residents (over 80%) the nutrition organisation in NHs was good. Over half of the subjects assessed the meals quality in NHs also as good. Only some comments were about insufficient quantities of fruits and vegetables and meal monotony.  相似文献   
998.
In this study, the authors examined the effects of alcohol, tobacco, and drug use on plasma testosterone and seminal parameters (in accordance with the World Health Organization's standards) in healthy Argentine medical students (n = 34). Some alterations in seminal parameters were detected in 19 (56%) subjects. Alcohol and tobacco use were correlated significantly, p = 0.005; subjects who used these substances exhibited a nonsignificant reduction in sperm concentration, motility, viability, and normal morphology. There was a significant decrease in sperm motility among students who used moderate amounts of aspirin (i.e., > or = 500 mg/wk). The authors concluded that alcohol, tobacco, and aspirin use could have had detrimental effects on seminal parameters and that men who wish to procreate should be warned of such effects. Doses, exposure time, and interactions with other variables deserve additional study.  相似文献   
999.
The aim of this study was to investigate the health risks due to combustor emissions in the manufacturing of Portland cement for the population living in the neighborhood of a cement kiln in Catalonia, Spain. Pollutants emitted to the atmosphere in the course of cement production were modeled. The ISC3-ST model was applied to estimate air dispersion of the contaminants emitted by the cement plant. Air concentrations of NO(2), SO(2), PM(10), metals, and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), as well as the potential exposure in the vicinity of the facility, were assessed via models based on US EPA guidance documents. PCDD/F and metal concentrations were also modeled for soil and vegetation. Based on these concentrations, the levels of human exposure were calculated. Individual cancer and noncancer risks for the emissions of the cement kiln were assessed. Health effects due to NO(2), SO(2), and PM(10) emissions were also evaluated. Risk assessment was performed as a deterministic analysis. The main individual risk in the population was evaluated in a central-tendency and a high-end approach. The results show that the incremental individual risk due to emissions of the cement plant is very low not only with regard to health effects, but also in relation to toxicological and cancer risks produced by pollutants such as metals and PCDD/Fs emitted by the cement kiln.  相似文献   
1000.
The human P2Y(13) receptor is a new receptor characterized by coupling to Gi, responsiveness to adenine di-phospho-nucleotides and blockade by the P2Y antagonist AR-C69931MX. The mouse P2Y(13) ortholog has also been reported. Here we report, for the first time, the cloning of rat P2Y(13) receptor, its pharmacological analysis and tissue distribution. Rat P2Y(13) is 79% and 87% identical to human and mouse P2Y(13) receptors, respectively. Expression of rP2Y(13) receptor in 1321N1 cells induced the appearance of responses to the typical P2Y(13) receptor agonists ADP and 2MeSADP, as detected by stimulation of [(35)S]GTPgammaS binding. Agonist activities were higher in cells transfected with rP2Y(13) receptor in the presence of the Galpha(16) subunit; in all cases agonist effects were abolished by pertussis toxin pre-treatment. At variance from both human and mouse receptors, ADP was more potent than 2MeSADP. Other nucleotides and sugar-nucleotides were ineffective. Both in the absence and presence of Galpha(16), activation of rP2Y(13) receptor by ADP and 2MeSADP was completely inhibited by nM concentrations of AR-C69931MX. In contrast, no inhibition of rP2Y(13) receptor was induced by the selective P2Y(1) receptor antagonist MRS2179. rP2Y(13) receptor showed highest expression levels in spleen, followed by liver and brain (with particularly high levels in cortex and striatum as reported in man), suggesting important roles in the nervous and immune systems. Expression levels comparable to those of the other cloned P2Y receptors were found in primary rat astrocytes, indicating a possible role in reactive astrogliosis. Hence, rat P2Y(13) receptor displays several similarities but also interesting differences with its human and mouse orthologs, that will have to be taken into account when characterizing the pathophysiological roles of this receptor in the rat animal models.  相似文献   
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