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排序方式: 共有275条查询结果,搜索用时 15 毫秒
71.
M Silengo E Belligni C Molinatto G Baldassare E Biamino N Chiesa O Zuffardi S Girirajan EE Eichler GB Ferrero 《Clinical genetics》2010,77(1):28-31
Silengo M, Belligni E, Molinatto C, Baldassare G, Biamino E, Chiesa N, Zuffardi O, Girirajan S, Eichler EE, Ferrero GB. Eyebrow anomalies as a diagnostic sign of genomic disorders. Microdeletions and microduplications in the human genome, termed genomic disorders, contribute to a high proportion of human multisystemic neurodevelopmental diseases and are detected by array‐based comparative genomic hybridization (aCGH). In general, most genomic disorders are associated with craniofacial and skeletal features and behavioural abnormalities, in addition to learning disability and developmental delay (LD/DD). Specifically, recognition of a characteristic ‘acial gestalt’ has been the key to distinguish one genomic disorder from the other. Here, we report our experience concerning the relevance of abnormal eyebrow pattern as a diagnostic indicator of specific genomic disorders. 相似文献
72.
Tjitske Hielkema Elisa G Hamer Heleen A Reinders-Messelink Carel GB Maathuis Arend F Bos Tineke Dirks Lily van Doormaal Johannes Verheijden Carla Vlaskamp Eline Lindeman Mijna Hadders-Algra 《BMC pediatrics》2010,10(1):1-8
Background
Bronchiolitis is the most common reason for admission of infants to hospital in developed countries. Fluid replacement therapy is required in about 30% of children admitted with bronchiolitis. There are currently two techniques of fluid replacement therapy that are used with the same frequency-intravenous (IV) or nasogastric (NG). The evidence to determine the optimum route of hydration therapy for infants with bronchiolitis is inadequate. This randomised trial will be the first to provide good quality evidence of whether nasogastric rehydration (NGR) offers benefits over intravenous rehydration (IVR) using the clinically relevant continuous outcome measure of duration of hospital admission.Methods/Design
A prospective randomised multi-centre trial in Australia and New Zealand where children between 2 and 12 months of age with bronchiolitis, needing non oral fluid replacement, are randomised to receive either intravenous (IV) or nasogastric (NG) rehydration. 750 patients admitted to participating hospitals will be recruited, and will be followed daily during the admission and by telephone 1 week after discharge. Patients with chronic respiratory, cardiac, or neurological disease; choanal atresia; needing IV fluid resuscitation; needing an IV for other reasons, and those requiring CPAP or ventilation are excluded. The primary endpoint is duration of hospital admission. Secondary outcomes are complications, need for ICU admission, parental satisfaction, and an economic evaluation. Results will be analysed using t-test for continuous data, and chi squared for categorical data. Non parametric data will be log transformed.Discussion
This trial will define the role of NGR and IVR in bronchiolitisTrail registration
The trial is registered with the Australian and New Zealand Clinical Trials Registry - ACTRN12605000033640 相似文献73.
74.
75.
Quistad GB Klintenberg R Caboni P Liang SN Casida JE 《Toxicology and applied pharmacology》2006,211(1):78-83
Three components of the cannabinoid system are sensitive to selected organophosphorus (OP) compounds: monoacylglycerol (MAG) lipase that hydrolyzes the major endogenous agonist 2-arachidonoylglycerol (2-AG); fatty acid amide hydrolase (FAAH) that cleaves the agonist anandamide present in smaller amounts; the CB1 receptor itself. This investigation considers which component of the cannabinoid system is the most likely contributor to OP-induced hypomotility in mice. Structure-activity studies by our laboratory and others rule against major involvement of a direct toxicant-CB1 receptor interaction for selected OPs. Attention was therefore focused on the OP sensitivities of MAG lipase and FAAH, assaying 19 structurally diverse OP chemicals (pesticides, their metabolites and designer compounds) for in vitro inhibition of both enzymes. Remarkably high potency and low selectivity is observed with three O-alkyl (C1, C2, C3) alkylphosphonofluoridates (C8, C12) (IC50 0.60-3.0 nM), five S-alkyl (C5, C7, C9) and alkyl (C10, C12) benzodioxaphosphorin oxides (IC50 0.15-5.7 nM) and one OP insecticide metabolite (chlorpyrifos oxon, IC50 34-40 nM). In ip-treated mice, the OPs at 1-30 mg/kg more potently inhibit brain FAAH than MAG lipase, but FAAH inhibition is not correlated with hypomotility. However, the alkylphosphonofluoridate-treated mice show dose-dependent increases in severity of hypomotility, inhibition of MAG lipase activity and elevation of 2-AG. Moderate to severe hypomotility is accompanied by 64 to 86% MAG lipase inhibition and about 6-fold elevation of brain 2-AG level. It therefore appears that OP-induced MAG lipase inhibition leads to elevated 2-AG and the associated hypomotility. 相似文献
76.
Three phosphotrichlorides [phosphorus trichloride (PCl(3)), phosphorus oxychloride (POCl(3)), and thiophosphoryl chloride (PSCl(3))] with an annual U.S. production of >500,000,000 pounds and their diethyl esters are intermediates in the production of organophosphorus pesticides, plastics, flame retardants, and hydraulic fluids. They are classified as highly toxic to mammals based on acute oral and inhalation data with rats. This study considers their mechanisms of toxicity. PCl(3) and POCl(3) inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) from several species with in vitro IC(50) values of 5-36 and 88-1200 microM, respectively; PSCl(3) is a less potent inhibitor. These phosphotrichlorides have high vapor toxicity to houseflies with in vivo inhibition of brain AChE activity correlating with mortality. PCl(3) and POCl(3) produce cholinergic poisoning signs on ip administration to mice, and all three phosphotrichlorides give marked in vivo inhibition of serum BChE but not brain AChE activity. PCl(3) is a direct acting AChE inhibitor. Our earlier proposed activation of POCl(3) is confirmed here by preparing pure Cl(2)P(O)OH and its potassium and dicyclohexylamine salts that reproduce the action of POCl(3) as in vitro AChE inhibitors and toxicants in mice. PSCl(3) on hydrolysis yields Cl(2)P(O)SH [which oxidizes with peracid to Cl(2)P(O)SOH] as the proposed activation product. Vapors of (EtO)(2)PCl, (EtO)(2)P(O)Cl, and (EtO)(2)P(S)Cl are lethal to houseflies as in vivo AChE inhibitors, the first two acting directly and the last one on oxidative activation to (EtO)(2)P(O)Cl (possibly by P450) or (EtO)(2)P(O)SCl (a phosphorylating agent in a peracid oxidation system). Thus PCl(3), (EtO)(2)PCl, and (EtO)(2)P(O)Cl act directly as AChE inhibitors whereas POCl(3) and PSCl(3) undergo hydrolytic activation and (EtO)(2)P(S)Cl undergoes oxidative activation. In contrast, the toxicity to mice of phosphofluorides [FP(O)Cl(2), F(Cl)P(O)OH, and F(2)P(O)OH; studied as model compounds for comparison] may be due to liberating fluoride ion. 相似文献
77.
78.
Akanchha?Kesari Hanna?Rennert Debra?GB?Leonard Balraj?MittalEmail author 《BMC medical genetics》2005,6(1):22
Background
Spinal muscular atrophy (SMA) represents the second most common fatal autosomal recessive disorder after cystic fibrosis. Due to the high carrier frequency, the burden of this genetic disorder is very heavy in developing countries like India. As there is no cure or effective treatment, genetic counseling becomes very important in disease management. SMN1 dosage analysis results can be utilized for identifying carriers before offering prenatal diagnosis in the context of genetic counseling. 相似文献79.
Progesterone stimulates p42 extracellular signal-regulated kinase (p42erk) in human spermatozoa 总被引:1,自引:3,他引:1
Luconi M; Krausz C; Barni T; Vannelli GB; Forti G; Baldi E 《Molecular human reproduction》1998,4(3):251-258
Mitogen-activated protein kinases (MAPK), also known as extracellular
signal-regulated kinases (ERKs) are cytoplasmic and nuclear
serine/threonine kinases involved in signal transduction of several
extracellular effectors. Recently, we have demonstrated that ERKs are
present in spermatozoa and are involved in the regulation of the process of
capacitation. We report here the effect of progesterone, a well-known
inducer of the acrosome reaction in mammalian spermatozoa, on the
immunolocalization, phosphorylation and activity of ERKs in capacitated
human spermatozoa. We demonstrated that short-term incubation of
spermatozoa with progesterone induces phosphorylation and activation of
ERKs, resulting in redistribution of the proteins from the post-acrosomal
region to the equatorial segment within the sperm head. To investigate the
role of ERKs on the biological effects of progesterone, we used the MAPK
cascade inhibitor PD098059, which strongly inhibited progesterone-induced
activation of ERK-2. This compound did not inhibit progesterone-induced
acrosome reaction, although it prevented redistribution of the enzyme to
the equatorial region of the sperm head. These results suggest that the two
processes, although temporally related, are independent. In conclusion, we
provide new insight into the signal transduction pathways involved in the
non- genomic action of progesterone in spermatozoa and suggest a possible
involvement of ERKs in the process of fertilization.
相似文献
80.
组织工程注射骨的体外实验研究 总被引:1,自引:0,他引:1
目的 :探索骨髓间充质细胞在纤维胶内体外成骨的可行性。方法 :5× 10 6~ 10× 10 6细胞 /毫升的骨髓间充质细胞植入前行细胞活力测定 ;植入纤维胶 ,体外培养 60 d后进行组织学、免疫组织化学分析。结果 :细胞在纤维胶内产生大量的特异性 型胶原 ,并有大量的钙质沉着。结论 :骨髓间充质细胞在纤维胶内可在体外培养的环境下生成大量的骨基质。 相似文献