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71.
Mitochondrial cytochrome b genes (cyt b) of 40 strains of Cryptococcus neoformans were partially sequenced to determine the genetic relations. With the exception of the type strain of C. neoformans var. neoformans, all strains contained introns in their sequences. Analysis of 386 bp of coding sequence from each strain under investigation revealed a total of 27 (6.99%) variable nucleotide sites and categorized isolates of C. neoformans into nine cyt b types. C. neoformans var. gattii included cyt b types I to V, and C. neoformans var. neoformans comprised types VI to IX. cyt b types were correlated with serotypes. All strains with cyt b types I, IV, and V were serotype B. All other strains except IFM 5878 (serotype B) with cyt b types II and III were serotype C. Serotype D strains had cyt b types VI and IX, and serotype A strains were cyt b type VIII. Of four serotype AD strains, one was cyt b type VII and the remaining three were type VIII. The phylogenetic tree based on deduced amino acid sequences divided the strains only into C. neoformans var. neoformans and C. neoformans var. gattii. These results indicate that cyt b sequences are effective for DNA typing as well as phylogenetic analysis of C. neoformans.  相似文献   
72.
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors.  相似文献   
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We previously demonstrated that fluoride release from resins could be regulated by the polysiloxane coating of the fluoride additives. The present study investigated the effects of regulated fluoride release from resin on enamel demineralization in vitro. Bovine enamel cavities were restored with bis-GMA/TEGDMA resins containing 50 wt% NaF powders treated with or without gamma-methacryloxypropyltrimethoxysilane. Specimens were immersed in distilled water that was changed daily to measure the amount of fluoride released over 40 days, and thereafter subjected to pH-cycling. Microradiographic observations were performed to determine total mineral loss (AZ) and lesion depth (Ld) on the enamel. In addition, fluorine distribution was analyzed using EPMA. The resin containing untreated NaF exhibited high-rate and short-term fluoride release, whereas the resin containing treated NaF released low concentrations of fluoride over a longer period. The former showed high fluorine uptake in the adjacent enamel. In contrast, the latter showed high fluorine uptake not only in the adjacent enamel, but also in a wider area of enamel surface. The latter also showed lower AZ and Ld values in the surrounding enamel, indicating a high inhibitory effect on caries formation. Therefore, it is suggested that regulated fluoride release from the resin based on polysiloxane coating is effective in preventing caries formation.  相似文献   
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Summary To identify amyloid deposits in the anterior pituitary gland, we have immunohistochemical, histochemical and alkaline Congo red staining. The anti-human P component reacted positively with these amyloid deposits, while antisera against prealbumin, AA type amyloid fibril protein and various anterior pituitary hormones were negative. A combination of Congo red and anti-human P component staining was most sensitive and reliable for detection of amyloid in the anterior pituitary glands of 300 randomly autopsied patients. Amyloid deposits increased in parallel with the age of the patients, however, they appeared earlier and more frequently than heretofore reported. Deposition of amyloid was seen initially in the 3rd decade and the positivity rate of amyloid deposits was 73% in the 5th decade. The histochemical characteristics of these pituitary amyloid deposits differed from those of cerebral and systemic deposits, particularly those found in the amyloid of senile systemic amyloidosis.This study was supported in part by a grant from the Fundation for Advancement of Clinical Medicine and Ministry of Health and Welfare of Japan  相似文献   
77.
MML(Medical Markup Language)是一套不同医疗设施间的数据交换规格。于1995年在日本被开发。MML从版本2.21开始使用XML(eXtensible Markup Language)作为标记语言。而最新版本3.0又遵循HL7Clincal Document Architecture(CDA),包含14模块和36个数据定义表格。目前在中国,还没有一个使用XML来结构整个病历内容的规格。鉴于MML的柔韧性,我们制作了一个基于3.0版本的汉化版。日本与中国虽然诊疗流程、病历记录的内容等都很相似,但是也有一些,比如民族的表现、中医诊断分类,医师资格分类等都是日本不存在的或者分类不同的信息。另外,因为国情不同,医疗保险制度也完全不同。为了使MML能在中国的医院适用,我们追加和更改了12个数据定义表格,并重新制作了医疗保险信息模块。MML汉化版不止是一个对原规格的翻译和说明,它还考虑了本地的需要。因此,使用MML汉化版在中国的医疗设施间进行医疗数据交换已经成为可能。  相似文献   
78.
Polyvinyl chloride (PVC) tubing is an indispensable medical material for extracorporeal circulation therapy. However, di(2-ethylhexyl)phthalate (DEHP), a suspected endocrine disruptor, can be eluted from PVC, suggesting that an alternative material that does not contain DEHP is needed for clinical applications. First, we evaluated the endocrine disrupting risks of the plasticizers contained in PVC tubes by investigating their binding affinities for the human estrogen receptor alpha (ERα). Our results revealed that, while DEHP has some binding affinity for ERα, neither epoxidized soybean oil nor tris(2-ethylhexyl)trimellitate (an alternative to DEHP) has any affinity for ERα. Second, we evaluated the endocrine disrupting risks of a tube made of newly developed plasticizer-free (PF) materials. We confirmed the presence of DEHP and detected several unidentified substances in plasma stored within the PVC tube. This plasma's competitive binding affinity for ERα was significantly higher than that of control plasma (P < 0.01). In contrast, the profile of plasma stored in the PF tube was similar to that of the control, both in terms of high-performance liquid chromatography chromatograms and competitive binding capacity for ERα, suggesting that the PF tube is biocompatible and is useful for reducing the elution of substances capable of binding to ERα. Presented in part at the 42nd Congress of the Japanese Society for Artificial Organs, October 5–7, 2004, Tokyo, Japan  相似文献   
79.
Polyelectrolyte complexes (PEC) were prepared from chitosan as the polycation and several synthesized functional anion polysaccharides, and their effects on cell attachment, morphology, proliferation and differentiation were estimated using normal human osteoblasts (NHOst). After a 1-week incubation, PEC made from polysaccharides having carboxyl groups as polyanions showed low viability of NHOst on it although the NHOst on it showed an enhancement in their differentiation level. On the other hand, NHOst on PEC made from sulfated or phosphated polysaccharides showed similar attachment and morphology to those on the collagen-coated dish. When the number of NHOst was estimated after 1 week, the number on the PEC was ranged from 70% to 130% of those on the collagen-coated dish, indicating few effects of these PEC on cell proliferation. In addition, NHOst on PEC films made from sulfated polysaccharides differentiated to a level very similar to that observed on the collagen-coated dish, indicating that these PEC films maintain the normal potential of NHOst to both proliferate and differentiate. Measurement of gap junctional intercellular communication of NHOst on PEC revealed that PEC did not inhibit communication, suggesting that PEC films have few effects on cell homeostasis. Thus, PEC made from the sulfated polysaccharide may be a useful material as a new scaffold for bone regeneration.  相似文献   
80.
In acute hypotension, an automated drug infusion system to control mean arterial blood pressure (MAP) has not been previously studied, though many investigations have examined the use of vasodilating drugs to control MAP in postoperative hypertension. Therefore, we examined an automated control of MAP during acute hypotension using a neural network (NN) approach. A proportional-integral-derivative (PID) control, an adaptive predictive control using a NN (APC(NN)), a combined control of APC(NN) and PID (APC(NN-PID)), a fuzzy control, and a model predictive control were tested in computer simulation based on the MAP response to norepinephrine (NE) of 25 microg ml(-1). In six anesthetized rabbits, using the NE of 25 microg ml(-1), the PID control, APC(NN), and APC(NN-PID) prevented severe hypotension compared to an uncontrolled condition. Under PID control, four of the six animals showed MAP oscillation. Using NE of 50 microg ml(-1), the rabbits recovered from acute hypotension for all systems tested but showed sustained MAP oscillation during PID control. In conclusion, utilization of a NN for adaptive predictive control systems could facilitate the development of an automated drug infusion apparatus because it provides robust control even when acute or large perturbations and inter-individual differences in the sensitivity to therapeutic agents occur.  相似文献   
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