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11.
INTRODUCTION: The clinical presentation of morphea varies from localized plaques to generalized eruptions. Its cause remains unknown and medical treatments have often proved unsatisfactory. Studies have previously shown that improvement of hypertrophic scars and fibrotic skin can be achieved with the use of a 585 nm pulsed dye laser (PDL). METHODS: A case of plaque-type morphea was treated with 585 nm pulsed dye laser irradiation at an average fluence of 5.0 J/cm2 at bimonthly time intervals. RESULTS: Marked clinical improvement as evidenced by improved pliability and skin coloration was seen after 4 successive PDL treatments. No side effects or complications were encountered. CONCLUSION: Pulsed dye laser therapy is a viable treatment option for morphea. The mechanism of its effect in this condition remains unknown. 相似文献
12.
Effect of arachidonic acid metabolites on bone resorption by isolated rat osteoclasts 总被引:3,自引:0,他引:3
Arachidonic acid metabolites (eicosanoids) have major effects on bone but their role is unclear. Many are known to stimulate bone resorption in organ culture, but paradoxically, previous work has suggested that at least some of them act as direct inhibitors of osteoclastic function. In an attempt to clarify the role of eicosanoids in bone physiology, we have defined the duration of action and relative potencies of prostaglandin (PG) E1 and E2 and have extended the range of eicosanoids tested on isolated osteoclasts. We have found that PGE1 and PGE2 inhibited bone resorption by isolated osteoclasts for at least 6 h. Inhibition was followed by recovery to control, not supranormal levels. Bone resorption was inhibited in the range 10(-5)-10(-9) M for PGE1 and PGE2, and the rank order as resorption inhibitors was PGE1 greater than 6-keto PGE1 greater than PGE2 greater than PGA2 greater than PGB2. None of the products of lipoxygenase metabolism showed a significant direct effect. The effects of PGE1 and PGE2 were not antagonistic. Prostaglandin production does not seem to be implicated as a second messenger for the action of calcitonin. Although inhibition of osteoclasts by PGs was less prolonged than that observed in the presence of calcitonin, the sensitivity of osteoclasts to inhibition by PGs, and the duration of the effect without subsequent direct stimulation, suggests that inhibition of osteoclastic resorption is a major physiological role of PG production in bone. 相似文献
13.
D J Chambers M V Braimbridge D J Hearse 《European journal of cardio-thoracic surgery》1987,1(2):80-90
The isolated perfused working rat heart model of cardiopulmonary bypass was used to assess whether (a) allopurinol pretreatment enhances resistance to normothermic (30 min) or hypothermic (4 h) ischemia; (b) addition of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) to cardioplegic and/or reperfusion solutions are protective; (c) any protective effects are additive. With normothermic ischemia, allopurinol pretreatment improved recovery of aortic flow from its control value of 25 +/- 3% to 48 +/- 6% (P less than 0.05). Similarly, SOD plus CAT used during both ischemia and reperfusion improved recovery of aortic flow from a control value of 28 +/- 4% to 48 +/- 6% (P less than 0.05). However, various combinations of the two types of intervention afforded no additive protection. Under hypothermic (21 degrees C) conditions, allopurinol pretreatment was not effective, whereas SOD and CAT added during ischemia and reperfusion improved recovery of aortic flow from its control value of 53 +/- 4% to 69 +/- 5% (P less than 0.05). This value was similar to allopurinol pretreatment and SOD plus CAT added during ischemia and reperfusion (69 +/- 6%: P less than 0.05). These results provide further evidence that reperfusion-induced free radical formation may adversely affect postischemic recovery of function. The absence of an additive effect suggests a common mechanism of action, which is likely to involve the free radical-generating enzyme xanthine oxidase; however, other mechanisms may exist. Our results further support the use of antifree radical intervention in conjunction with cardioplegia to protect the heart during ischemia and reperfusion. 相似文献
14.
Bradley J Catalone Shendra R Miller Mary Lee Ferguson Dan Malamud Tina Kish-Catalone Nina J Thakkar Fred C Krebs Mary K Howett Brian Wigdahl 《Biomedicine & Pharmacotherapy》2005,59(8):430-437
C31G, which has potent activity against the human immunodeficiency virus type 1 (HIV-1) and an established record of safety in animal studies and human trials, is a microbicidal agent comprised of a buffered equimolar mixture of two amphoteric, surface-active agents: an alkyl amine oxide (C14AO) and an alkyl betaine (C16B). Studies of long-term in vitro exposure to C31G and its constituents have suggested that the components of C31G may contribute differentially to its toxicity and efficacy. In the present studies, in vitro assays of cytotoxicity and anti-HIV-1 activity demonstrated that C16B was slightly less cytotoxic compared to either C31G or C14AO, whereas the anti-HIV-1 activities of C31G and its individual constituents were similar. In the murine model of cervicovaginal microbicide toxicity, in vivo exposure to C14AO resulted in severe cervical inflammation followed by a delayed disruption of the columnar epithelium. In contrast, exposure to C16B caused severe cervical epithelial disruption and a secondary, less intense inflammatory response. These results demonstrate that (i) there are both mechanistic and temporal differences in toxicity associated with the components of C31G not necessarily predicted by in vitro assessments of cytotoxicity and (ii) contributions of each component to the anti-HIV-1 activity of C31G appear to be equal. In addition, these findings indicate that direct and indirect mechanisms of in vivo toxicity can be observed as separate but interrelated events. These results provide further insight into the activity of C31G, as well as mechanisms potentially associated with microbicide toxicity. 相似文献
15.
OBJECTIVE: This study was designed to investigate potential areas of practice for the clinical laboratory scientist (CLS) and to propose a graduate curriculum to prepare the practitioner for an advanced level of practice. DESIGN: Meta-analysis of PharmD, physician assistant, physical therapy, and nurse practitioner curricula focusing on academic and clinical advanced practice was used to develop an educational model and curriculum for a professional doctorate in clinical laboratory science (CLS). MAIN OUTCOME MEASURE: (1) New educational model for CLS advanced practice; (2) A proposed curriculum for a Doctorate of Clinical Laboratory Science degree. RESULTS: A new curriculum model was adapted from established healthcare educational models. CONCLUSION: Although there is a need for a baccalaureate degree in CLS there is also a role for expanded education and responsibilities for CLS practitioners. The CLS Advanced Practitioner design focuses on moving students from the baccalaureate level to the doctoral level and prepares the individual to become an integral part of the healthcare team. 相似文献
16.
Abstract: Background : Women are increasingly being asked to consider participating in medical research. We sought to investigate views of women who participated in and declined to participate in a study that was part of a program of maternity care research. Methods : An exploratory study using focus group interviews and semistructured interviews was conducted. A purposive sample of 17 postnatal women who had participated in research, from a hospital in the North West of England, were interviewed. An open coding mechanism to identify emergent themes was used for the analysis of data. Results : Of women who had not declined to participate in any research, the following themes were identified: altruism versus self‐protection, enhanced versus inferior care, professional guidance versus self‐direction, and welcome versus unacceptable methodology. Of women who had participated in some research but declined to participate in other research, the following themes were identified: feeling disempowered by the process, inability to believe equipoise existed, and practical inconvenience. Conclusions : These findings suggest that although health care researchers adopt an individualistic approach to care, they may fail to adopt a similar approach within research. What is important and acceptable to women needs to be ascertained to develop appropriate research strategies. This plan will ensure that research is carried out to the highest ethical standard, which may increase recruitment rates. 相似文献
17.
Evaluation of cilofungin (LY121019) for treatment of experimental Candida albicans endocarditis in rabbits. 总被引:6,自引:6,他引:0
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The efficacy of cilofungin (LY121019) for aortic valve endocarditis caused by Candida albicans in rabbits was studied. Vegetation titers were similar for cilofungin-treated and untreated rabbits. No rabbit survived beyond 5 days in either group. All rabbits given amphotericin B survived, and titers were reduced. Cilofungin was ineffective in this model. 相似文献
18.
Vandana Jain Supriya Dabir Debraj Shome Tina Dadu Sundaram Natarajan 《Survey of ophthalmology》2009,54(2):286
We report the case of a 25-year-old male patient who presented with complaints of redness, photophobia, and decreased vision in the right eye of a week's duration. Slit-lamp biomicroscopic examination revealed a cream-colored, irregular elevated inferior iris mass, extending on to the anterior lens surface. Differential diagnoses of a fungal granuloma, a medulloepithelioma, and an amelanotic melanoma were considered. An excisional biopsy of the mass was performed through a superior clear corneal incision. Polymerase chain reaction analysis of the aqueous humor showed a positive pan fungal genome. Histopathology of the biopsied mass showed a giant cell granuloma with surrounding numerous branching, septate hyphae. Culture growth revealed Aspergillus fumigatus We report this case because of the rarity of Aspergillus iris granuloma as a primary presentation of endogenous Aspergillosis and review the relevant literature. Absence of a significant systemic history compounded the diagnostic dilemma in our patient. Definitive differentiation of this rare entity from a foreign body, amelanotic melanoma, and other inflammatory conditions such as sarcoidosis and tuberculosis, may be possible only on microbiological and histo-pathological evaluation. 相似文献
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