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排序方式: 共有660条查询结果,搜索用时 15 毫秒
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I Richard O Broux D Hillaire D Cherif F Fougerousse D Cohen J S Beckmann 《Human molecular genetics》1992,1(8):621-624
Limb-Girdle Muscular Dystrophy (LGMD) is a myopathy with clinical and transmission heterogeneity. The recessive form, LGMD2, has been recently mapped by linkage analysis to 15q. As an attempt to identify the gene involved in this pathology, we tested as candidate gene the LD locus, called LD for limb deformity. This gene has recently been identified and mapped to chromosome 15q13-q14. It is homologous to the murine formin gene which is localized to mouse chromosome 2. Mutations in this murine gene have been shown to cause limb deformity and kidney defect. YAC clones containing the LD gene were isolated and utilised to confirm the cytogenetic localisation. Internal DNA polymorphisms of the LD locus were analyzed in LGMD2 and CEPH families. The LD gene was mapped between the alpha cardiac actin gene and the D15S24 locus. Crossovers between the LGMD2 and the LD loci excluded the LD gene as a candidate for LGMD2. 相似文献
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Salam Bennouar Abdelghani Bachir Cherif Amel Kessira Djamel-Eddine Bennouar Samia Abdi 《Nutrition Clinique et Métabolisme》2021,35(2):144-151
Introduction/ObjectivesAcute kidney injury (AKI) and malnutrition are two complications commonly reported in severe forms of COVID-19, their combined effect on short-term mortality is, however, not yet investigated. The objective of this study is to determine both their individual and combined effects on short-term prognosis.Materials and methodsThis is a prospective, uni-centric study, including 247 severe COVID-19 patients, admitted between April 25th and June 20th, 2020, at the University Hospital of Blida. AKI was defined according to the KDIGO-2012 guidelines. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score. The association with in-hospital mortality was assessed using the Kaplan-Meier method and proportional Cox regression.ResultsAmong the 247 severely affected COVID-19 patients included in this study, 34.4% developed AKI, 30.4 and 1.2%, respectively, had moderate and severe CONUT scores, 17.7% worsened and progressed to a critical state and 26.7% did not survive. Both AKI and CONUT score were significantly associated with mortality in a dose-response manner (pLog-Rank < 0.0001). Their relative risks are respectively (HR = 3.25 CI 95% [1.99–5.3] and HR = 2.42 CI 95% [1.5–3.9], p < 0.0001). In multivariate analysis, the highest risk was observed for the AKI-CONUT-high combination (HR = 3.0, 95% CI [1.5–6.1], p = 0.002).ConclusionA possible synergistic interaction between AKI and CONUT score for COVID-19 short-term mortality has been highlighted. Monitoring of renal function associated with assessment of nutritional status should be performed routinely and systematically from the early stages of admission. 相似文献
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Hassib A. Sahyoun Brenda Costall Robert J. Naylor 《Naunyn-Schmiedeberg's archives of pharmacology》1982,319(1):8-11
Summary Dopamine was shown to act on the circular smooth muscle of the stomach body to cause contraction at a yohimbine-sensitive site (2) and a relaxation at a prazosin-sensitive site (1). Metoclopramide and tiapride failed to modify either response, failed to antagonise a relaxation to phenylephrine at 1(1 sites in the same tissue, and failed to modify the contractions caused by dopamine and phenylephrine at an 2-adrenoceptor site in the pyloric sphincter. However, (+)- and (–)-sultopride and (+)-sulpiride antagonised the dopamine-induced contractions of the stomach body indicating an 2-antagonist action. An ability to attenuate the relaxation of this tissue may reflect a displacement of the contraction curve to the right rather than an 2-antagonist action since the response to phenylephrine was not antagonised either in this tissue or in the pyloric sphincter. Within the central nervous system the (–)-enantiomers of sultopride and sulpiride have a highly selective dopamine receptor blocking action. This cotrasts with the present findings in the stomach musculature of a non-stereospecific antagonism at 2-type adrenoceptors. 相似文献
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We sought to identify risk factors and neonatal outcomes associated with the failure of the INSURE method ( INtubation- SURfactant- Extubation) during nasal continuous positive airway pressure for preterm infants with respiratory distress syndrome. We used a retrospective analysis of the prenatal histories, clinical courses, and laboratory data of all inborn infants with gestational age 27 to 34 weeks and respiratory distress syndrome treated with INSURE method. Infants were categorized into two groups: INSURE failure group and INSURE success group. One hundred nine infants were eligible to the study. INSURE failure was registered in 35 infants (32.1%). After control for confounding variables, INSURE failure was significantly associated with arterial partial pressure of carbon dioxide (adjusted odds ratio [OR] = 1.82; 95% confidence interval [CI] = 1.76 to 90.56), mean arterial-to-alveolar oxygen tension ratio (adjusted OR = 1.13; 95% CI = 1.06 to 85.34) and severe radiological grade (adjusted OR = 1.31; 95% CI = 1.15 to 70.16). Positive predictive values of these variables were 70, 75, and 55%, respectively. Patent ductus arteriosus and mortality rates were significantly higher in INSURE failure group. Arterial partial pressure of carbon dioxide, arterial-to-alveolar oxygen tension ratio, and severe radiological grade are predictors of the failure of INSURE method in preterm infants with respiratory distress syndrome. However, a prospective randomized controlled trial is needed to determine whether or not infants at risk for INSURE failure are better off being treated with mechanical ventilation. 相似文献
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Oral ibuprofen in early curative closure of patent ductus arteriosus in very premature infants 总被引:1,自引:0,他引:1
Intravenous indomethacin and intravenous ibuprofen are widely used for the treatment of patent ductus arteriosus (PDA) in premature infants. Intravenous indomethacin may lead to renal impairment, enterocolitis, and intraventricular hemorrhage. Intravenous ibuprofen was shown to be as effective and to cause fewer side effects. If ibuprofen is effective intravenously, it will probably be effective orally, too. This study was conducted to test oral ibuprofen in early curative closure of PDA in very premature infants hoping for a better tolerance and the same efficacy as intravenous ibuprofen. Forty very premature infants (mean gestational age: 29.4 +/- 1 to 2 weeks [range: 26 to 31.5 weeks]; mean weight: 1237.2 +/- 198 g [range: 650-1770 g]) with PDA and respiratory distress were studied prospectively. They received, while between 48 and 96 hours old, oral ibuprofen at a dose of 10 mg/kg, followed, if needed, at 24-hour intervals by one or two additional doses of 5 mg/kg each. Color Doppler echography of the heart, brain, and abdomen were performed before treatment and after each dose administration. Ductal closure, early outcome (1 week after treatment), and late outcome were recorded. Thirty-eight patients (95%) achieved pharmacological closure. Two patients did not respond to the treatment: One required surgical ligation of the ductus, and the other patient received and well tolerated ductal shunting. Twenty-four patients were treated with one dose of oral ibuprofen, 10 were treated with two doses, and 6 were treated with three doses. Early outcome showed no case of renal impairment, no significant differences in serum creatinine levels, nine cases (22.5%) of intraventricular hemorrhage, three cases (7.5%) of necrotizing enterocolitis, and two cases (5%) of gastrointestinal bleeding. Late outcome showed 15 cases (37.5%) of nosocomial sepsis, 3 cases (7.5%) of chronic lung disease, 2 cases (5%) of periventricular leukomalacia, and 17 cases of death. In this study, oral ibuprofen was effective and well tolerated for early curative closure of PDA in very premature infants. Nevertheless, larger randomized comparative studies with pharmacokinetics measures are warranted. 相似文献
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Properties of the interaction of fluoride- and guanylyl-5''-imidodiphosphate-regulatory proteins with adenylate cyclase.
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M Hebdon H Le Vine rd N Sahyoun C J Schmitges P Cuatrecasas 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(8):3693-3697
The mechanism of activation of adenylate cyclase by guanylyl-5'-imidodiphosphate [Gpp(NH)p] and NaF has been investigated by studying the reconstitution of Gpp(NH)p and NaF sensitivity of an enzyme rendered insensitive to these agents by differential detergent extraction of a particulate brain enzyme. Such reconstitution can be achieved by the addition of macromolecular regulatory factors from membranes of various tissues. Trypsin digestion and thermal inactivation provide evidence for the existence of two distinct regulatory functions, one capable of restoring the Gpp(NH)p response and another the NaF response. The regulatory protein(s) seem to interact with their respective activators in an easily reversible, divalent cation-independent reaction. This appears to be followed by a high-affinity interaction between the catalytic and regulatory components of adenylate cyclase in a slow, temperature-dependent, divalent cation-dependent process tha produces the persistently activated state of the enzyme. The enzyme activation can be reversed by methods that separate catalytic from regulatory components and the resulting enzyme activity can be restimulated by the reconstitution technique. 相似文献
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