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Efficient systems for in vitro translation are of importance for biochemical and gene expression studies as well as for biotechnological developments. We optimized a cell-free translation system using subcellular fractions from human placenta and high quality placental tRNAs isolated using a simple and fast procedure. The postmitochondrial fraction or a reconstituted system containing soluble proteins plus polysomes were able to efficiently translate endogenous and exogenous mRNAs. Optima for ions, enzymes, tRNA and energy mix components were determined for a poly(U)-directed poly(Phe) synthesis test. The use of homologous tRNAPhe, omission of commercial creatine kinase, and addition of 3.5 mM spermidine at near physiological magnesium concentration (2.5 mM), were the most significant improvements. Under optimal conditions, poly(Phe) synthesis proceeded at a maximal initial rate of 1.2 Phe/80S/min at 37 degrees C, while natural mRNA translation by S-30 started at a near in vivo estimated rate of 0.3-0.5 amino acid/80S/sec. Furthermore, natural mRNA directed the synthesis of a family of polypeptides closely resembling the pattern of cytoplasmic proteins in both, molecular weight and relative amounts. This efficient and faithful system is of interest for biochemical studies of the human translational machinery, as well as a basis for screening new drugs affecting protein synthesis in pathogenic microorganisms.  相似文献   
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We describe a baby girl of 4,000 g and 55 cm with supernumerary, malformed, and partially duplicated lower limbs, malformed and partially duplicated pelvis, spina bifida, coccygeal dermal sinus, ectopic anus located in the right buttock, duplicated internal genitalia, rectovaginal fistula, ileal atresia, Meckel diverticulum, and various renal system anomalies. We think that this phenotype is a new case of disorganization in humans (DsH) and postulate that this condition constitutes a polytopic defect of the blastogenesis. In this case, the presence of a malformation pattern involving structures in different parts of the body and organs derived from all of the germ layers, suggests that the pathogenetic event most probably occurred during blastogenesis affecting various progenitors fields.  相似文献   
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BACKGROUND: Previous studies have documented that various behavioral disturbances accompany Sydenham's chorea, a neurologic variant of rheumatic fever. Further, an immunological marker associated with rheumatic fever (monoclonal antibody D8/17) has been reported to be elevated in several neuropsychiatric disorders, most frequently tics and obsessive-compulsive disorder. We examined this association in a community sample of children previously identified as being D8/17 positive or negative. It was hypothesized that D8/17 positivity would predict increased rates of tics and obsessive-compulsive disorder, even in the absence of Sydenham's chorea. Possible associations with other disorders accompanying Sydenham's chorea--hyperactivity, anxiety, and depression, also were explored. METHOD: From 1991 to 1995, 2631 children (mean age = 9.6 +/- 1.6 years) from a low socioeconomic area of Mexico City were screened for the D8/17 marker. In a 2- to 5-year follow-up of 240 of these children (108 positive and 132 negative), structured psychiatric interviews and rating scales were administered to the child and main caretaker. Assessments were conducted and scored blind to the child's D8/17 status. RESULTS: No association was seen between D8/17 positivity and tics or OCD. CONCLUSION: This study failed to provide support for the generalized use of D8/17 as a marker of susceptibility to tics and OCD in a community sample.  相似文献   
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The degree of acceptation of irrigation from a colostomy varies ostensibly from some cases to others, therefore, we study what occurs in our medium, separating those patients which have previously undergone other procedures (Group A) from those patients who have been informed and trained about the immediate postoperative period (Group B). GROUP A: 48 patients, 22 or 46% of these patients were considered not apt for irrigation. Of the 26 to whom this procedure was proposed, 14 or 54% accepted. Of these, 5 or 36% abandoned its use while 9 continued its use; this is 64% of those who accepted this procedure, 35% of those to whom it was proposed and 19% of the total study group. GROUP B: 189 patients. This procedure was not recommended to 95 patients, 50%. Of the 94 patients to whom this procedure was proposed, 65 or 69% accepted. Of these, 22 or 34% abandoned its use while 43 continued its use; this is 66% of those; who accepted this procedure, 46% of those to whom it was proposed and 23% of the total study group. CONCLUSIONS: In our medium, the practice of irrigation oscillates between 19 and 23% of patients who have undergone a colostomy, without any significant difference referring to the moment when a patient started this procedure. A first report on this study was submitted in the III National Congress for Nursing in Colostomies.  相似文献   
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Immune-based therapies, such as therapeutic vaccination, that might preserve, restore, enhance and induce new HIV-specific immunologic responses are currently being explored. HIV-specific immunotherapy with Remune (The Immune Response Corp.) offers the opportunity to boost immune responses against HIV-1. The clinical trial program in a wide range of subjects has established the efficacy of Remune in stimulating an appropriate immune response in HIV-positive individuals. Furthermore, a recent unblinded study conducted in Europe has documented a significant effect of Remune on viral load. Evidence regarding clinical end points is more difficult to collect. The same studies have revealed no serious safety issues in a total of more than 2000 Remune-treated patients. It is therefore reasonable to suggest that the risk-benefit ratio of Remune could be positive.  相似文献   
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After an extensive review which the author has presented in her previous articles on relaxation, in this article she tries to evaluate the workshops set up in Primary Health Care Centers. She evaluates relaxation exercises, those problems which may occur while performing these and possible exercises which may be carried out at home. Finally, the author comments on the need to establish a personal relaxation plan adjusted to the necessities of each individual.  相似文献   
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