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1.
Behavior, genetics and biochemistry of an allele of the mutant mouse spastic, spaAlb 总被引:1,自引:0,他引:1
A new autosomal recessive mutation, characterized by an early defect in righting reflex and stiffened gait, progression to severe spasticity, tremor and rigidity, and death before weaning, appeared spontaneously on the C57BL/6 background. It was shown to be an allele of the mutant spastic spa, and shall be known as spaAlb. Mutant levels of [3H]strychnine binding are less than 10% of control levels in the brainstem and spinal cord. Autoradiographic examination of the distribution of [3H]strychnine binding sites in the mutant confirm a greatly reduced level of binding compared to control in all areas of the spinal cord, brainstem, and midbrain. 相似文献
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C W Taylor W S Dalton P R Parrish M C Gleason W T Bellamy F H Thompson D J Roe J M Trent 《British journal of cancer》1991,63(6):923-929
We selected two drug resistant variants of the MCF7 human breast cancer cell line by chronic in vitro exposure to doxorubicin (MCF7/D40 cell line) and mitoxantrone (MCF7/Mitox cell line), respectively. The cell lines are similar in growth characteristics including doubling time, DNA synthetic phase and cell size. Resistance to mitoxantrone conferred only partial resistance to doxorubicin; whereas resistance selected for doxorubicin appeared to confer complete resistance to mitoxantrone. Both agents selected for cross resistance to the Vinca alkaloids. MCF7/D40 cells display a classic-multi-drug resistance phenotype with expression of P-glycoprotein, decreased drug accumulation relative to the parental line and reversal of drug accumulation and drug resistance by verapamil. MCF7/Mitox cells likewise display resistance to multiple drugs, but in contrast to MCF7/D40 cells do not express P-glycoprotein by immunoblot or RNA blot analysis. Net drug accumulation in MCF7/Mitox cells was decreased relative to the parental cells but there was no selective modulation of drug accumulation or in vitro drug resistance by the addition of verapamil. Efflux of mitoxantrone was enhanced in both the MCF7/D40 and MCF7/Mitox cell lines relative to the MCF7/S cell line. We conclude that the two drug resistant cell lines have different mechanisms of decreased drug accumulation. 相似文献
4.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献
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Bastiaan R Klarenbeek Alexander AFA Veenhof Elly SM de Lange Willem A Bemelman Roberto Bergamaschi Piet Heres Antonio M Lacy Wim T van den Broek Donald L van der Peet Miguel A Cuesta 《BMC surgery》2007,7(1):16
Backround
Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis. 相似文献6.
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This study examines the need for a comprehensive patient educationprogram that emphasizes self-help for adults living with HIV/AIDS.Data were collected using a self-administered, written questionnaire.Participants were recruited from agencies in northern California.This study revealed that 59 of 70 respondents were relativelysatisfied with the services, including patient education, availablein their community. Of the 70 respondents, 69 felt there wasa need for a comprehensive patient education program. The study'sfindings illustrate both distinct differences and commonaltiesbetween the experiences, perceived needs and priorities of maleand female respondents. These findings will help HIV/AIDS serviceagencies re-structure their health education programs and assistin patient education program development. Future research inthis area needs to address the perceived needs and prioritiesof different subgroups living with HIV/AIDS. 相似文献
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Joan Stiles Pamela Moses Katherine Roe Natacha A Akshoomoff Doris Trauner John Hesselink Eric C Wong Lawrence R Frank Richard B Buxton 《Journal of the International Neuropsychological Society》2003,9(4):604-622
The current study presents both longitudinal behavioral data and functional activation data documenting the effects of early focal brain injury on the development of spatial analytic processing in two children, one with prenatal left hemisphere (LH) injury and one with right hemisphere (RH) injury. A substantial body of evidence has shown that adults and children with early, lateralized brain injury show evidence of spatial analytic deficits. LH injury compromises the ability to encode the parts of a spatial pattern, while RH injury impairs pattern integration. The two children described in this report show patterns of deficit consistent with the site of their injury. In the current study, their longitudinal behavioral data spanning the age range from preschool to adolescence are presented in conjunction with data from a functional magnetic resonance imaging (fMRI) study of spatial processing. The activation results provide evidence that alternative profiles of neural organization can arise following early focal brain injury, and document where in the brain spatial functions are carried out when regions that normally mediate them are damaged. In addition, the coupling of the activation with the behavioral data allows us to go beyond the simple mapping of functional sites, to ask questions about how those sites may have come to mediate the spatial functions. 相似文献