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21.
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD) locus of the X chromosome has duplicated to specific locations near the pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11. Comparative sequence analysis reveals 92-96% nucleotide identity, indicating that the autosomal ALD paralogs arose relatively recently during the course of higher primate evolution (5-10 million years ago). Analysis of sequences flanking the duplication region identifies the presence of an unusual GCTTTTTGC repeat which may be a sequence-specific integration site for the process of pericentromeric- directed transposition. The breakpoint sequence and phylogenetic analysis predict a two-step transposition model, in which a duplication from Xq28 to pericentromeric 2p11 occurred once, followed by a rapid distribution of a larger duplicon cassette among the pericentromeric regions. In addition to facilitating more effective mutation detection among ALD patients, these findings provide further insight into the molecular basis underlying a pericentromeric-directed mechanism for non- homologous interchromosomal exchange.   相似文献   
22.

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
23.
Optical disk technology is a move to the future. It is an exciting time to brave the new frontiers and change from a manual to an optical disk system. Since the technology is so new in health care environments and because each facility is unique, there is no "right" way to do optical imaging. Opportunities flourish to "do it your way." The process is challenging and time consuming, but the rewards of providing health information users with a quality record system make the investment worthwhile. Complete, thorough planning and education will ease the transition to tomorrow's system. Stop dreaming, make a commitment, and move forward--optical disk systems in health care are achievable successes!  相似文献   
24.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、…  相似文献   
25.
A sensitive and specific electrospray ionization high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) method has been developed for the quantitative determination of alprazolam (AL) and alpha-hydroxyalprazolam (OH-AL) in plasma. After the addition of deuterium labeled internal standards of AL and OH-AL, plasma samples were buffered to alkaline pH and extracted with toluene/methylene chloride (7:3). Dried extract residues were reconstituted in HPLC mobile phase and injected onto a reversed-phase C18 HPLC column. The analytes were eluted isocratically at a flow rate of 250 microL/min using a solvent composed of methanol and water (60:40) containing 0.1% formic acid. The analyses were performed using selected reaction monitoring. The assay was sensitive to 0.05 ng/mL for both the parent drug and metabolite and linear to 50 ng/mL. The intra-assay percent coefficients of variation (%CV) for AL at 2, 5, and 20 ng/mL were all < or = 5.6. At these concentrations, and all OH-AL intra-assay %CVs were < or = 8.4. The interassay variabilities for AL were 11.8%CV, 8.7%CV, and 8.7%CV at 2.0, 5.0, and 20.0 ng/mL, respectively. The OH-AL interassay variabilities were 9.6%CV, 9.2%CV, and 7.8%CV at the same concentrations, respectively. The assay accuracy was less than or equal to +/- 6.6% for both analytes at the three concentrations. The method was used to quantitate AL and OH-AL in plasma samples collected from 10 subjects who were administered a 1-mg oral dose of AL. The mean AL concentration peaked at 11.5 ng/mL 1 h after the dose and AL was detectable for 48 h. The mean OH-AL concentration peaked at 0.18 ng/mL 4 h after the dose and was undetectable by 36 h. Hydrolysis of the plasma samples had little effect on the detected AL concentrations but increased OH-AL concentrations substantially. Plasma/blood ratios for AL and OH-AL exceeded 1 in the study samples.  相似文献   
26.
In this study, the instruction of undergraduate students in Maitland's grades (I-IV) for posterior glenohumeral mobilization as a valid instructional goal was investigated. Undergraduate students were instructed in Maitland's mobilization grades I-IV at various joints before the experimentation. Students selected were mobilized by the instructor. A random assignment of grades was given to the instructor before mobilization. The mobilization subject secretly identified the grade as the mobilization was being videotaped. The videotape was played to the class of undergraduate students who were asked to identify the grades visually. The accuracy of the student's ability to identify the assigned grades visually and kinesthetically was determined to be within the projected 90% accuracy level; therefore, the hypothesis was substantiated.J Orthop Sports Phys Ther 1980;1(4):214-221.  相似文献   
27.
This molecular epidemiologic case-control study of lung cancer incorporated three complementary biomarkers: the glutathione S- transferase M1 (GSTM1) null genotype, a potential marker of susceptibility, and polycyclic aromatic hydrocarbon-DNA adducts (PAH- DNA) and sister chromatid exchanges (SCE), both indicators of environmentally induced genetic damage. Associations between biomarkers and lung cancer were investigated, as were possible gene-environment interactions between the GSTM1 null genotype and tobacco smoke exposure. Subjects included 136 primary non-small cell lung cancer surgical patients and 115 controls at the Columbia Presbyterian Medical Center. Questionnaire and Tumor Registry data, pre-treatment blood samples and biomarker measurements on blood were obtained. Overall, GSTM1 null genotype was significantly associated with lung cancer [odds ratio (OR) = 2.04, 95% confidence interval (CI) = 1.13-3.68]. ORs for GSTM1 and lung cancer were significant in females (2.50, 1.09-5.72) and smokers (2.25, 1.11-4.54) and not significant in males (1.4, 0.58-3.38) and non-smokers (0.88, 0.18-4.33). However, ORs for males versus females and smokers versus non-smokers did not differ significantly. The OR for GSTM1 and lung cancer in female smokers was 3.03 (1.09- 8.40), compared with 1.42 (0.53-4.06) in male smokers. In contrast to PAH-DNA adducts in leukocytes, SCE did not differ between cases and controls. Neither biomarker differed significantly between the two GSTM1 genotypes. The combined effect of elevated PAH-DNA adducts and GSTM1 genotype on case-control status (16.19, 1.2-115) appeared multiplicative. Results suggest that the effect of the GSTM1 null genotype is greatest in female smokers, which is consistent with other evidence that indicates that women are at higher risk of lung cancer than males, given equal smoking. Persons with both the GSTM1 deletion and elevated PAH-DNA adducts may represent a sensitive subpopulation with respect to carcinogens in tobacco smoke and other environmental media.   相似文献   
28.
Objective. To develop data collection methods suitable to obtain data to assess the costs, cost-efficiency, and cost-effectiveness of eight types of HIV prevention programs in five countries.
Data Sources/Study Setting. Primary data collection from prevention programs for 2002–2003 and prior years, in Uganda, South Africa, India, Mexico, and Russia.
Study Design. This study consisted of a retrospective review of HIV prevention programs covering one to several years of data. Key variables include services delivered (outputs), quality indicators, and costs.
Data Collection/Extraction Methods. Data were collected by trained in-country teams during week-long site visits, by reviewing service and financial records and interviewing program managers and clients.
Principal Findings. Preliminary data suggest that the unit cost of HIV prevention programs may be both higher and more variable than previous studies suggest.
Conclusions. A mix of standard data collection methods can be successfully implemented across different HIV prevention program types and countries. These methods can provide comprehensive services and cost data, which may carry valuable information for the allocation of HIV prevention resources.  相似文献   
29.
Hepatic artery infusion (HAI) chemotherapy is associated with higher response rates compared to systemic chemotherapy in those patients with unresectable liver malignancies. Operative hepatic artery catheter (HAC) insertion has significant morbidity and mortality, especially in patients with high‐volume disease, some of whom may not respond to HAI chemotherapy. We report our experience in 45 patients with high‐volume liver disease who were initially treated with HAI chemotherapy via a radiologically placed temporary HAC to try to select the responders who then went on to have an operative HAC. In these 45 patients who had 62 radiologically placed HAC, we found very few major complications, and certainly no complications such as cholecystitis, vascular or malperfusion problems.  相似文献   
30.
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