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61.
Two cases of menopausal age women with acute coronary syndromes are presented. Clinical symptoms and diagnostic tests were similar for women and for men. Gender differences in angiographic lesion pathophysiology were found. The substrate for thrombosis in women was probably plaque erosion. 相似文献
62.
Tissue factor (TF), the primary cellular initiator of blood coagulation, is also involved in cancer-related processes such as hypercoagulability (Trousseau syndrome), tumor growth, angiogenesis, and metastasis. Indeed, elevated TF expression by cancer cells and their associated endothelial cells has been reported frequently. Oncogenic events in cancer cells (e.g., expression of mutant K- ras, EGFR, PTEN or p53) lead to an increase in TF levels and activity, and thereby promote tumor aggressiveness, angiogenesis, and hypercoagulability. Like TF, thrombin receptor (protease-activated receptor-1) is also upregulated in cancer cells expressing oncogenic K -ras. Pharmacological antagonists of some of these transforming genes (e.g., epidermal growth factor receptor inhibitors) could diminish TF expression, both locally and systemically, and hence these targeted agents could be viewed as potential indirect and cancer-specific anticoagulants, in addition to their direct antitumor effects. We postulate that levels of circulating TF may be useful in monitoring the biological activity of these agents. Although TF is essential for vascular development, its expression by tumor-associated endothelium appears to play a subtle and seemingly dispensable role. Thus, TF is a pivotal element of the tumor-vascular interface, is involved in many cancer-related processes, and may well constitute a promising new target for anticancer combination therapies in some disease settings. 相似文献
63.
64.
Miller SA Coelho SG Zmudzka BZ Beer JZ 《Photodermatology, photoimmunology & photomedicine》2006,22(2):59-66
BACKGROUND: The development of new pigmentation (tan) in human skin after UV exposure requires several days. Once it is developed, the tan can last for weeks. Current recommendations for tanning exposure schedules in the USA (FDA Letter to Manufacturers: Policy on maximum timer interval and exposure schedule for sunlamps, August 21, 1986) allow exposures three times per week for the development of a tan, and one to two times per week for maintenance exposures. However, this policy is often interpreted in the indoor tanning industry as allowing three exposures per week on a continuous basis. We believe that the reduction of the recommended cumulative dose to indoor tanners should be explored. Two approaches for achieving this are (1) decreasing the number of exposures and (2) increasing the time interval between exposures. To explore such changes, we conducted a pilot study. METHODS: The pilot study involved three exposure schedules (evaluated on each of six subjects) that evolved throughout the course of the study. Digital photography, visual assessment and diffuse reflectance spectrometry were used to assess skin color changes. The six pilot subjects were studied for 8-18 weeks. The changes in skin color obtained through the use of the different exposure schedules were compared with changes reported by Caswell (Caswell M, The kinetics of the tanning response to tanning bed exposures, Photodermatol Photoimmunol Photomed 2000: 16: 10-14) who used schedules based on current recommendations. RESULTS: Two out of the three experimental schedules produced tans comparable with those reported by Caswell. In these two schedules, cumulative doses were a factor of 2-3 below doses from current schedules. CONCLUSION: The UV burden to indoor tanners can be substantially reduced without compromising the cosmetic effect. These results need to be confirmed in a larger study. 相似文献
65.
66.
Transplantation of human neuronal progenitor cells (HNPC) is being considered for neuroreplacement therapy in beta-amyloidosis associated with neuronal loss in Down's syndrome and Alzheimer's disease. However, the influence of amyloid-beta-containing brain environment on the development of HNPCs is unknown. Recently, we demonstrated that amyloid-beta peptide (Abeta) impaired differentiation of HNPCs in culture through oxidative stress. Now we studied the effect of neprilysin, an Abeta-degrading enzyme, on development of neuronal colonies from neurospheres of HNPCs in the presence of Abeta1-40. Neprilysin increased the number of neurospheres that formed colonies of neuron-like cells. This effect of neprilysin was associated with reduced amounts of the monomeric and dimeric Abeta that remained in culture supernatants as well as the Abeta uptaken by differentiating HNPCs. Phosphoramidon, a neprilysin inhibitor, attenuated these effects of neprilysin. In control cultures of HNPCs that grew without exogenous Abeta1-40, the treatment with neprilysin reduced the number of developing colonies. This effect might result from degradation by neprilysin of endogenous Abeta produced and secreted by HNPCs or other peptides that are involved in neuronal development. The results demonstrate that even a partial reduction of extracellular Abeta levels by neprilysin may facilitate development of HNPCs into neurons in an environment overloaded with Abeta. This finding suggests that neprilysin could facilitate neuroreplacement therapy with HNPCs in treatment of neurodegenerative diseases. 相似文献
67.
Jagielski J Kubiczek-Jagielska M Sobstyl M Koziara H Błaszczyk J Zabek M Zaleski M 《Neurologia i neurochirurgia polska》2006,40(2):127-133
BACKGROUND AND PURPOSE: In advanced stages of Parkinson's disease (PD) beside resting tremor, rigidity, and bradykinesia, most patients reveal severe balance instability. The goal of this study is to determine objectively postural control changes using static posturography after neurosurgical treatment (unilateral posteroventrolateral pallidotomy). MATERIAL AND METHODS: 15 patients with advanced idiopathic PD underwent unilateral posteroventrolateral pallidotomy. The study group was composed of 8 men and 7 women. The mean disease duration until operation was 12.5+/-3.5 years, and the mean age of the patients at the time of surgery was 65.8+/-4.1 years. Postural control changes were assessed objectively by static computerized posturography and subjectively according to items of posture, gait and postural stability derived from Part III (motor examination) UPDRS. All evaluations of the balance system were performed preoperatively in the off and on condition, and also two weeks postoperatively in the same conditions. RESULTS: It was found that the majority of posturographic parameters in the off condition were improved after neurosurgical treatment. The improvement in the on condition was less pronounced. For example, the mean path length in the off condition during eyes opened was 318+/-159 mm before pallidotomy, and after surgery it was 240.9+/-119.2 mm in off. The difference was statistically significant (p < 0.005, t=3.11). CONCLUSIONS: Pallidotomy improves postural control changes in the early postoperative period, which can be proved by static computerized posturography. 相似文献
68.
Otfinowski J Jasiak-Tyrkalska B Starowicz A Reguła K 《Neurologia i neurochirurgia polska》2006,40(2):112-118
OBJECTIVE: To evaluate the usefulness of the computer program made for the patients after stroke to treat their cognitive impairments and hemiparesis. RESEARCH DESIGN AND METHODS: The experimental group involved 10 patients after stroke who were obliged to train on a computer every day during their three-week stay on the rehabilitation ward. The control group involved 10 patients after stroke who did not participate in any computer training during their rehabilitation process. The first part of the computer tasks trains the attention impairments and visual-motor co-ordination problems. We modified the joystick by adding special buttons to train movements of the wrist, thumb and forefinger of the impaired hand. Computer tasks are made in the way to stimulate both the cognitive functions and hand dexterity at the same time. RESULTS: This initial research shows a statistically significant improvement of the cognitive functions and hand dexterity among patients from the experimental group. According to these results we did not observe any significant improvement in the cognitive functions among patients who did not train on a computer (control group). CONCLUSIONS: The results of this research suggest the usefulness of this computer program in training cognitive impairments and visual-motor co-ordination as well as hand dexterity among the patients after stroke. 相似文献
69.
Kazmierski J Kowman M Banach M Pawelczyk T Okonski P Iwaszkiewicz A Zaslonka J Sobow T Kloszewska I 《General hospital psychiatry》2006,28(6):536-538
Preoperative risk factors of postoperative delirium were evaluated in 260 patients admitted for open heart surgery. The incidence of delirium was 11.5%. Independent predictors included cognitive impairment, atrial fibrillation, a history of peripheral vascular disease major depression and advanced age. Aforementioned factors might be helpful in predicting delirium following cardiac surgery. 相似文献
70.
Klonowski S Klatka J Szymański M 《Otolaryngologia polska. The Polish otolaryngology》2005,59(6):899-901
The authors present a case of a huge osteoma of the ethmoid and frontal sinuses. An operative technique enabling radical removal without fragmentation of the tumor with preservation of the bony margins of the fronto-orbital region was presented. 相似文献