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101.
The photodynamic therapy (PDT) efficiency of five phthalocyanines, chloroaluminum phthalocyanine (AlPc), dichlorosilicon phthalocyanine (SiPc), bis(tri-n-hexylsiloxy)silicon phthalocyanine (PcHEX), bis(triphenylsiloxy)silicon phthalocyanine (PcPHE) and nickel phthalocyanine (NiPc), was assessed on two leukemic cell lines TF-1 and erythroleukemic and B lymphoblastic cell lines, Daudi, respectively. AlPc showed the best photocytotoxicity leading to 0.008 surviving fraction at 2 x 10(-9) M for TF-1 and 4 x 10(-9) M for Daudi. A1 5 x 10(-7) M, SiPc and PcHEX induced a significant photokilling, whereas NiPc and PcPHE were inactive. Laser flash photolysis and photoredox properties of the phthalocyanines were investigated to try to relate these parameters with the biological effects. AlPc showed the longest triplet life-time: 484 microseconds in dimethyl sulfoxide/H2O. This value was increased up to 820 microseconds when AlPc was complexed with human serum albumin used as a membrane model. Such an enhancement was not observed with the silicon phthalocyanines. Upon irradiation, all the phthalocyanines generated singlet oxygen with 0.29-0.37 quantum yield values. The reduction potentials of the excited states obtained from measurement in the ground state and energy of the excited triplets show that AlPc is the best electron acceptor. The in vitro photocytotoxicity observed and the measured parameters are in agreement with a key role of electron transfer in PDT assays involving these phthalocyanines.  相似文献   
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A 24-year-old woman suffered from ano-rectal Crohn's disease and nephrotic syndrome due to glomerular amyloidosis AA. She received azathioprine and colchicine for two years. Both Crohn's disease and nephrotic syndrome resolved. However amyloid renal lesions were still present. This course is exceptional, and leads to a discussion of the treatment of amyloidosis associated with Crohn's disease.  相似文献   
105.
Fifty-eight new anonymous simple sequence repeats (SSR) were generated and mapped to various rat chromosomes. Among them two genes (rat homologs for human cadherin-14 and mouse fibroblast growth factor-related protein) were mapped on Chromosomes (Chrs) 2 and 11 respectively. The majority of markers were generated from a small insert genomic library specific to Chr 11, 13, 14, and 15. Twenty new markers were mapped to Chr 13, which is known to contain a blood pressure quantitative trait locus (QTL). Several approaches to obtain microsatellite markers are described. The protocols and newly generated markers should be useful for ongoing rat genome project.  相似文献   
106.
A computer assisted technique of iliosacral screw placement that is applicable to unstable pelvic ring fractures is proposed. The goals are to operate noninvasively with a percutaneous procedure to decrease the complications of surgical exposure and to provide greater accuracy in locating the close neurovascular structures. Preoperative computed tomographic images of the pelvis are provided and a computed tomography three-dimensional model is built. In this model, the optimal trajectories for the drilling are planned. An ultrasound based registration is performed intraoperatively. This registration is the most original part of this work. After performing the passive drilling guidance step, the surgeon places the screws. The accuracy of the ultrasound based registration is checked by comparison with a standard surface based registration at the end of the test experiment. Each screw position is verified by a computed tomographic examination. Four human anatomic specimen pelves were tested with three screw insertions for each pelvis (12 screws). All of the screws were considered to be placed correctly. The method is safe and encourages the start of clinical application.  相似文献   
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The effect of age on the presentation and outcome of infective endocarditis (IE) is unclear. Many of the available data are based on analyses of mixed populations of patients including intravenous drug users or those with prosthetic valve endocarditis or native valve IE. We used the Duke criteria to compare the characteristics of 44 episodes of definite native valve IE in elderly patients (> 64 years old) with the characteristics of 64 similarly defined episodes of native valve IE in younger, nonintravenous-drug-using adult patients (> 29 years and < 60 years old). Our data suggest that the clinical presentation, characteristics, and outcome of native valve IE are similar for elderly patients and younger adult patients, although elderly patients were hospitalized an average of 12 days longer. Although we found that the occurrence of renal failure and cerebral embolism during an episode of IE was associated with higher rates of death (odds ratios, 4.8 and 4.0, respectively), age was not a significant contributor to mortality.  相似文献   
109.
PURPOSE: The present study evaluated the expression of alpha1-adrenoceptor subtypes in human corpus cavernosum. MATERIALS AND METHODS: The mRNA encoding alpha1a, alpha1b and alpha1d subtypes were assessed by RNA-directed complementary cDNA synthesis followed by Taq DNA amplification. The level of alpha1 mRNA was calculated in arbitrary optical density units and normalized with respect to the length of the respective cDNA fragments. RESULTS: We found that alpha1a, alpha1b and alpha1d adrenoceptor subtypes are expressed in human corpus cavernosum, with a predominant expression of the alpha1a subtype. CONCLUSION: These results suggest that alpha1a-adrenoceptor subtype is important and that understanding the biochemical and functional characteristics of this subtype may lead to the development of specific antagonists in the treatment of impotence.  相似文献   
110.
In this report, we demonstrate the utility of interleukin-2 (IL-2) stimulation of spleen cell cultures and bivariate flow cytometry in the analysis and purification of the C57BL/6J mouse Y Chromosome. We determined that the DNA content of the C57BL/6J Y Chromosome is approximately 94.7 Mb, making it similar in size to human Chromosome 16 and significantly larger than previous estimates. In addition, we describe the bulk isolation of mouse Y Chromosomes and demonstrate enrichment of the isolated material using a fluorescence in situ hybridization strategy. We detail the construction of two small insert Y Chromosome-specific libraries, ideal for sampling Y Chromosome sequences. From these libraries 1566 clones were analyzed. We provide a detailed characterization of 103 clones, generating nearly 50 kb of sequence. For 30 of these clones, we identify regions of homology to known Y chromosomal sequences, confirming the enrichment of the sorted DNA. From the remaining characterized clones, we describe the development of 15 male-specific PCR assays and 19 male-female PCR assays potentially originating from the pseudoautosomal region or other areas of X-Y or autosome-Y homology.  相似文献   
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