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61.
LG Lee SL Spurgeon CR Heiner SC Benson BB Rosenblum SM Menchen RJ Graham A Constantinescu KG Upadhya JM Cassel 《Canadian Metallurgical Quarterly》1997,25(14):2816-2822
We have synthesized a set of four energy transfer dyes and demonstrated their use in automated DNA sequencing. The donor dyes are the 5- or 6-carboxy isomers of 4'-aminomethylfluorescein and the acceptor dyes are a novel set of four 4,7-dichloro-substituted rhodamine dyes which have narrower emission spectra than the standard, unsubstituted rhodamines. A rigid amino acid linker, 4-aminomethylbenzoic acid, was used to separate the dyes. The brightness of each dye in an automated sequencing instrument equipped with a dual line argon ion laser (488 and 514 nm excitation) was 2-2.5 times greater than the standard dye-primers with a 2 times reduction in multicomponent noise. The overall improvement in signal-to-noise was 4- to 5-fold. The utility of the new dye set was demonstrated by sequencing of a BAC DNA with an 80 kb insert. Measurement of the extinction coefficients and the relative quantum yields of the dichlororhodamine components of the energy transfer dyes showed their values were reduced by 20-25% compared with the dichlororhodamine dyes alone. 相似文献
62.
DF Zatzick DS Weiss CR Marmar TJ Metzler K Wells JM Golding A Stewart WE Schlenger WS Browner 《Canadian Metallurgical Quarterly》1997,162(10):661-665
OBJECTIVE: This investigation assessed whether current post-traumatic stress disorder (PTSD) was associated with impaired functioning in a nationally representative sample of female Vietnam veterans. METHODS: Logistic models were used to determine the association between PTSD and outcome while adjusting for demographic characteristics and medical and psychiatric co-morbidities. RESULTS: PTSD was associated with significantly elevated odds of poorer functioning in five of the six outcome domains; only the association between perpetration of violence in the past year and PTSD did not achieve statistical significance. After adjusting for demographics and medical and psychiatric co-morbidities, PTSD remained associated with significantly elevated odds of bed days, poorer physical health, and currently not working. CONCLUSIONS: Among female Vietnam veterans PTSD is associated with a broad profile of functional impairment. The significantly increased odds of impaired functioning and diminished quality of life suggest that PTSD may be the core problem of the set of problems afflicting female Vietnam veterans. 相似文献
63.
T De Brito CR Carneiro MC Nakhle DM Lima CP Abrantes-Lemos M Sandoval AM Silva 《Canadian Metallurgical Quarterly》1998,6(4):368-376
Gene therapy has the potential to provide cancer treatments based on novel mechanisms of action with potentially low toxicities. This therapy may provide more effective control of loco-regional recurrence in diseases such as non-small cell lung cancer (NSCLC), as well as systemic control of micrometastases. Despite current limitations, retroviral and adenoviral vectors can in certain circumstances provide an effective means of delivering therapeutic genes to tumour cells. Although multiple genes are involved in the process of carcinogenesis, mutations of the p53 gene are the most frequent abnormality identified in human tumours. Pre-clinical studies both in vitro and in vivo have shown that restoration of p53 function can induce apoptosis in cancer cells. Phase I clinical trials now show that p53 gene replacement therapy is feasible and safe using both retroviral and adenoviral vectors, and that it induces tumour regression in patients with advanced NSCLC and recurrent head and neck cancer. Other pre-clinical studies indicate that gene therapy may have useful synergy with cytotoxic and radiation therapy. This paper describes the different gene therapy strategies under investigation and the pre-clinical data that provides a rationale for the gene replacement approach, reviews clinical trial data and presents novel ideas for improving current vectors and gene delivery to tumours. 相似文献
64.
OBJECTIVE: To analyze the short- and medium-term results of the Burch-like urethropexy with bone anchors in the treatment of genuine stress urinary incontinence. METHODS: We performed the conventional Burch technique which was modified with the use of 4 bone anchors for bony fixation. Forty-four female patients with genuine stress urinary incontinence were operated on from November, 1995 to November, 1997. RESULTS: The patients had a bladder catheter indwelling for 4 to 9 days and only 3 of them required intermittent catheterization during two months. All patients recovered spontaneous micturition. The postoperative urinary continence was 93% at a mean follow-up of 11 months. CONCLUSIONS: Although our initial results seem encouraging, a continuous and objective follow-up is warranted to assess the long-term efficacy of this technique. 相似文献
65.
The effects of personal characteristics and perceptions of interdisciplinary collaboration on discharge planning communication were examined for nurses, physicians, and social workers in two hospitals. The model for the study explained 61.7% of the variance in discharge planning communication for nurses. For all 142 health professionals, communication openness with social workers, problem solving between nurses and physicians, and collaboration with social workers were important to discharge planning communication. For nurses, communication satisfaction with patients and families also was important. 相似文献
66.
An acquired vaginal stricture in a llama secondary to trauma from uterine torsion during gestation was repaired, using a carbon-dioxide laser. The procedure was accomplished by use of epidural anesthesia with the llama in a standing position. Repeated dilation of the vagina was required after surgery; however, the llama subsequently mated and conceived, and a male cria was delivered by cesarean section at the end of a full-term gestation. 相似文献
67.
RL Richards M Rao NM Wassef GM Glenn SW Rothwell CR Alving 《Canadian Metallurgical Quarterly》1998,66(6):2859-2865
Encapsulation of soluble protein antigens in liposomes was previously shown to result in processing of antigen via the major histocompatibility complex class I pathway, as evidenced by costaining of the trans-Golgi region of murine bone marrow-derived macrophages (BMs) by fluorophore-labeled liposomal antigen and by a trans-Golgi-specific fluorescent lipid. Evidence is presented here that free or liposome-encapsulated RTS,S, a particulate malaria antigen consisting of hepatitis B particles coexpressed with epitopes from the Plasmodium falciparum circumsporozoite protein, also was localized in the trans-Golgi after incubation with BMs, suggesting processing by the class I pathway. An in vivo cytotoxic T-lymphocyte (CTL) response was detected, however, only after immunization with RTS,S encapsulated in liposomes containing lipid A and not after immunization with free RTS,S or with RTS,S encapsulated in liposomes lacking lipid A. Therefore, intracellular delivery of antigen containing CTL epitopes to the Golgi of BMs does not necessarily result in a CTL response in vivo unless an additional adjuvant, such as liposomes containing lipid A, is utilized. Encapsulation of RTS,S in liposomes containing monophosphoryl lipid A (MPL) resulted in a dose-dependent enhancement of the NANP-specific immunoglobulin G (IgG) antibody response compared to that of free RTS,S. The IgG1 and IgG2a subclasses predominated after immunization with RTS,S encapsulated in liposomes containing MPL. These results demonstrate that encapsulation of a lipid-containing particulate antigen, such as RTS, S, in liposomes containing lipid A can enhance both humoral and cellular immune responses. 相似文献
68.
Denaturing gradient gel electrophoresis revealed changes in the bacterial species obtained from enrichment cultures with different inoculum dilutions. This inoculum dilution enrichment approach may facilitate the detection and isolation of a greater number of bacterial species than traditional enrichment techniques. 相似文献
69.
70.
Cholinephosphotransferase (EC 2.7.8.2) catalyzes the formation of a phosphoester bond via the transfer of a phosphocholine moiety from CDP-choline to diacylglycerol forming phosphatidylcholine and releasing CMP. A motif, Asp113-Gly114-(X)2-Ala117-Arg118-(X)8-Gly127+ ++-(X)3-Asp131-(X)3-Asp135, located within the CDP-choline binding region of Saccharomyces cerevisiae cholinephosphotransferase (CPT1 ?/Author: Please confirm that a gene is meant here.) is also found in several other phospholipid synthesizing enzymes that catalyze the formation of a phosphoester bond utilizing a CDP-alcohol and a second alcohol as substrates. To determine if this motif is diagnostic of the above reaction type scanning alanine mutagenesis of the conserved residues within S. cerevisiae cholinephosphotransferase was performed. Enzyme activity was assessed in vitro using a mixed micelle enzyme assay and in vivo by determining the ability of the mutant enzymes to restore phosphatidylcholine synthesis from radiolabeled choline in an S. cerevisiae strain devoid of endogenous cholinephosphotransferase activity. Alanine mutants of Gly114, Gly127, Asp131, and Asp135 were inactive; mutants, Ala117 and Arg118 displayed reduced enzyme activity, and Asp113 displayed wild type activity. The analysis described is the first molecular characterization of a CDP-alcohol phosphotransferase motif and results predict a catalytic role utilizing a general base reaction proceeding through Asp131 or Asp135 via a direct nucleophilic attack of the hydroxyl of diacylglyerol on the phosphoester bond of CDP-choline that does not proceed via an enzyme bound intermediate. Residues Ala117 and Arg118 do not participate directly in catalysis but are likely involved in substrate binding or positioning with Arg118 predicted to associate with a phosphate moiety of CDP-choline. 相似文献