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71.
V. Bataille J. A. Bishop P. Sasieni A. J. Swerdlow E. Pinney K. Griffiths J. Cuzick 《British journal of cancer》1996,73(12):1605-1611
The atypical mole syndrome (AMS) phenotype, characterised by a large number of common naevi as well as atypical naevi, has been described in families with a genetic susceptibility to melanoma. However, the importance of this phenotype for melanoma in the general population has not been conclusively determined. This study was designed to examine the types and distribution of naevi as well as the prevalence of the AMS phenotype in melanoma patients in England compared with controls. A total of 426 cutaneous melanoma cases (61% of all incident cases) aged 16-75 years were recruited between 1989 and 1993 from the north-east Thames region of the UK and 416 controls from the same age group were recruited over the same period and from the same region. Each subject answered a questionnaire covering demographic details, sun exposure history and other risk factors and underwent a skin examination with total body naevus count performed by a dermatologist. The AMS phenotype was defined using a scoring system. Atypical naevi gave the highest relative risk for cutaneous melanoma, with an odds ratio (OR) of 28.7 (P < 0.0001) for four or more atypical naevi compared with none. Many common naevi were also an important risk factor: the OR for 100 or more naevi 2 mm or above in diameter compared with 0-4 naevi was 7.7 (P < 0.0001). Melanoma was also associated with naevi on sun-exposed sites but also with naevi on non-sun-exposed sites such as the dorsum of the feet, buttocks and anterior scalp. Sixteen per cent of the cases had the AMS phenotype compared with 2% of the controls (OR 10.4, P < 0.0001). The AMS phenotype was more common in males than females (P = 0.008). The odds ratio for the presence of the AMS phenotype was dependent on age, with an odds ratio of 16.1 (95% CI 4.6-57.5) for the presence of the AMS phenotype if aged less than 40 compared with an odds ratio of 6.9 (95% CI 2.9-16.6) if aged 40 or more. The AMS phenotype was strongly predictive of an increased risk of melanoma outside the familial context. 相似文献
72.
73.
Synthesis and antimicrobial activities of N-substituted imides 总被引:1,自引:0,他引:1
Zentz F Valla A Le Guillou R Labia R Mathot AG Sirot D 《Il Farmaco; edizione pratica》2002,57(5):421-426
In the field of our research programs concerning novel antimicrobial agents, a series of N-substituted imides was synthesized. These compounds were obtained by cyclization of amido-acids in acetic anhydride/sodium acetate or hexamethyldisilazane/zinc bromide for the hydroxy-aromatic derivatives. The hydroxy-alkyl maleimides were directly prepared by condensation of the corresponding amino-alcohol with maleic anhydride in boiling toluene. Most of N-substituted maleimides showed an interesting antimicrobial activity towards bacteria from the ATCC collection (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853) but the MIC values for P. aeruginosa were always high (128 microg/ml). The imides with alkyl substituents showed higher activities than aromatic analogues with MIC values in the range of 8-32 microg/ml. Comparatively, succinimides were practically inactive. 相似文献
74.
Levasseur R Barrios R Elefteriou F Glass DA Lieberman MW Karsenty G 《Endocrinology》2003,144(7):2761-2764
Gamma-glutamyl transpeptidase (GGT) is a widely distributed ectopeptidase responsible for the degradation of glutathione in the gamma-glutamyl cycle. This cycle is implicated in the metabolism of cysteine, and absence of GGT causes a severe intracellular decrease in this amino acid. GGT-deficient (GGT-/-) mice have multiple metabolic abnormalities and are dwarf. We show here that this latter phenotype is due to a decreased of the growth plate cartilage total height resulting from a proliferative defect of chondrocytes. In addition, analysis of vertebrae and tibiae of GGT-/- mice revealed a severe osteopenia. Histomorphometric studies showed that this low bone mass phenotype results from an increased osteoclast number and activity as well as from a marked decrease in osteoblast activity. Interestingly, neither osteoblasts, osteoclasts, nor chondrocytes express GGT, suggesting that the observed defects are secondary to other abnormalities. N-acetylcysteine supplementation has been shown to reverse the metabolic abnormalities of the GGT-/- mice and in particular to restore the level of IGF-1 and sex steroids in these mice. Consistent with these previous observations, N-acetylcysteine treatment of GGT-/- mice ameliorates their skeletal abnormalities by normalizing chondrocytes proliferation and osteoblastic function. In contrast, resorbtion parameters are only partially normalized in GGT-/- N-acetylcysteine-treated mice, suggesting that GGT regulates osteoclast biology at least partly independently of these hormones. These results establish the importance of cysteine metabolism for the regulation of bone remodeling and longitudinal growth. 相似文献
75.
El-Ghoneimi A Deffarges C Hankard R Jean-Eudes F Aigrain Y Jacqz-Aigrain E 《The Journal of urology》2002,168(2):694-697
PURPOSE: Intravesical morphine was recently recommended to reduce postoperative pain after reimplantation surgery for vesicoureteral reflux in children. The efficacy of such treatment, so far solely evaluated by open study, needed to be confirmed. MATERIALS AND METHODS: After parental informed consent was obtained, 80 children requiring Cohen cross-trigonal reimplantation were considered for inclusion in a double-blind study. On the day of surgery patients were randomly assigned to receive either 0.04 mg./kg. morphine per hour or placebo (normal saline) at a constant intravesical infusion rate of 0.08 ml./kg. per hour. Postoperative pain was assessed every 3 hours using a pain score adapted to patient age. If the score was above a predefined limit, patients received intravenous acetaminophen and nalbuphine alternately every 3 hours. Bladder infusion was discontinued after 48 hours. RESULTS: Mean and maximum pain scores as well as the number of scores above the limit were not statistically different when comparing the morphine and placebo groups. There was no difference in the number of doses of analgesics administered. Urine output, voiding frequency and the number of painful voiding episodes were not significantly different between the 2 groups. Plasma morphine concentrations were 3.0 +/- 2.7 and 1.9 +/- 1.9 ng./ml. at 24 and 48 hours in the morphine group and undetectable in the placebo group. CONCLUSIONS: Intravesical administration of morphine is not effective for relieving postoperative pain during the first 48 hours after intravesical ureteral reimplantation. This study emphasizes the importance of controlled studies in evaluating the effectiveness of a new drug or procedure before recommending its use for all patients. 相似文献
76.
Massé D Voisine C Henry F Cordel S Barbieux I Josien R Meflah K Grégoire M Lieubeau B 《Cancer research》2002,62(4):1050-1056
We have demonstrated previously the ability of apoptotic cells to prime a functional immune response using an i.p. vaccination protocol with apoptotic cells and interleukin 2, before injecting a lethal dose of tumor cells into syngeneic rats. This protocol resulted in a survival rate of 33%. To elucidate the nature and the activity of the phagocytes involved in the clearance of apoptotic cells in vivo, we modulated the peritoneal cavity environment by administrating either thioglycollate or silica i.p. before injecting the apoptotic cells. Our results showed that thioglycollate abrogated vaccination efficiency, because none of the rats survived under these conditions. In fact, thioglycollate treatment induced a massive recruitment and activation of inflammatory macrophages that efficiently engulfed apoptotic cells, bypassing induction of specific immune responses. In contrast, silica treatment enhanced the vaccination efficiency of apoptotic cells plus interleukin 2 up to 66%. We distinguished a population of dendrite-like cells among the cells derived from the silica-treated peritoneal cavity both by their phenotype (MHC II(+)/CD80(+)/CD86(+)) and by their ability to induce the proliferation of allogeneic T cells in a mixed leukocyte reaction. Our results demonstrate the different roles of macrophages and dendritic-like cells in the physiological clearance of dead tumor cells and their implication in the design of immunomodulating vaccines. 相似文献
77.
78.
Ciprofloxacin, a fluorinated quinolone, is a powerful antibiotic widely used for its broad spectrum of activity in ambulatory and long-term care setting. Until now, ciprofloxacin administration has been associated with a few cases of acute, sometimes cholestatic jaundice or fulminant hepatic failure believed mainly related to idiosyncratic hypersensitivity. We report a case of delayed and prolonged cholestatic hepatitis with ductopenia occurring after 6 months of treatment in a patient with Crohn's disease. This observation suggests the potential for the drug to induce long-term likely dose-related severe hepatotoxicity. 相似文献
79.
Wiechmann RJ Hanna RD Stange JA Johnson GH Fernandes RI Rozich JD 《The heart surgery forum》2002,6(1):24-29
Suture technique for valve replacement surgery has often focused on decreasing the soft tissue injury that leads to pseudoaneurysm formation and associated latent infection. There is universal recognition that precise suture placement is essential for avoiding adverse sequelae while allowing flexibility during the implantation of the prosthesis. The use of a continuous chain of linked horizontal mattress sutures (NextStitch) has allowed maximal precision in the approximation of sutures within the valve annulus. The product was used in a series of consecutive mitral and aortic valve replacements, and typical echocardiographic images from each type of implantation are presented. Postoperative echocardiography images revealed that no perivalvular leaks occurred and that NextStitch did not obscure detailed interrogation or assessment of the valve prosthesis. 相似文献
80.
Regis Verdier Sylvie Parer Helene Jean-Pierre Pierre Dujols Marie-Christine Picot 《Infection control and hospital epidemiology》2006,27(1):60-66
OBJECTIVE: To evaluate the impact of an infection control program in an intensive care unit (ICU). DESIGN: Prospective before-after study. Two 6-month study periods were compared; between these periods, an infection control program based on isolation was implemented. SETTING: Polyvalent ICU of Montpellier Teaching Hospital.Patients. Any patient who was hospitalized in the ICU for >48 hours and was discharged during 1 of the 2 periods. MAIN OUTCOME MEASURES: The main patient-related variables were sex, age at admission, type of patient (surgical, medical, or trauma), Simplified Acute Physiology Score II, length of ICU stay, need for intubation, duration of exposure to invasive devices, onset of nosocomial infection and pathogens responsible, and death. We compared the 2 study periods with respect to the incidence of 4 nosocomial infections (pneumonia, urinary tract infection, bacteremia, and catheter-associated infection), the frequency of infection with the main multidrug-resistant pathogens, and patient survival. RESULTS: Patients in periods 1 and 2 were similar with regard to sex, age, physiology score, and exposure to invasive devices. The rates of infection with multidrug-resistant pathogens were significantly lower during period 2 than during period 1 (infection rate: 28.1% of patients in period 1 and 9.6% of patients in period 2 [P = .01]; pneumonia rate: 32.6% of patients in period 1 and 4.2% of patients in period 2 [P = .008]). The mortality rate among patients with nosocomial pneumonia was 38.2% in period 1 and 4.3% in period 2 (P = .009). CONCLUSIONS: After implementation of an infection control program, the rate of infection with multidrug-resistant pathogens decreased, as did the mortality rate among patients with nosocomial pneumonia. 相似文献