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排序方式: 共有4075条查询结果,搜索用时 15 毫秒
991.
992.
DD Ivy EM Shaffer AM Johnson WJ Kimberling A Dobin PA Gabow 《Canadian Metallurgical Quarterly》1995,5(12):2032-2036
It is known that adults with autosomal dominant polycystic kidney disease (ADPKD) have an increased incidence of cardiovascular abnormalities, including mitral valve prolapse. The cardiac manifestations of ADPKD in the pediatric population have not been well established. To determine the cardiac manifestations of children with ADPKD, echocardiography was performed in 154 children of 66 families in which one parent has ADPKD. Eighty-six affected children and 68 unaffected children were evaluated in a prospective, single-blinded manner by echocardiography. Affected children were defined as those with any cysts on a concurrent renal ultrasound or those predicted to be gene carriers by gene linkage analysis. A 12% incidence of mitral valve prolapse was found in the affected children compared with only 3% of the unaffected children (P < 0.05). ADPKD children, but not their unaffected siblings, demonstrate a significant correlation between left ventricular mass index and systolic blood pressure. Moreover, hypertensive ADPKD children have significantly larger left ventricular mass index than do normotensive ADPKD children. A 3.5% incidence of congenital heart disease was found in the affected group, whereas 2.9% of the unaffected children had congenital heart disease. It was concluded that systemic manifestations of ADPKD, particularly cardiovascular abnormalities, are present even in childhood and these warrant the clinician's attention. 相似文献
993.
The enzyme methanol dehydrogenase (EC 1.1.99.8) from Hyphomicrobium X was used in an attempt to develop a rapid colorimetric test for methanol. The enzyme was stabilized for storage by lyophilization in the presence of the disaccharide trehalose. It was found that the enzyme retained significantly greater activity in the dried state with trehalose than without. The enzyme was partially purified by ammonium sulphate fractionation, after which it was found to be more stable in solution at pH 9 than at pH 7. A procedure is given which involves mixing a defined amount of enzyme with the methanol-containing water together with phenazine methosulphate (PMS), 2-6-dichlorophenol-indophenol (DCPIP) and cyanide, and observing the resultant colour change from blue to yellow if methanol is present. The sensitivity of the procedure is such that 9 mg L-1 of methanol can be readily detected. 相似文献
994.
Compartments, wingless and engrailed: patterning the ventral epidermis of Drosophila embryos 总被引:1,自引:0,他引:1
Recent experiments on the wing disc of Drosophila have shown that cells at the interface between the anterior and posterior compartments drive pattern formation by becoming the source of a morphogen. Here we ask whether this model applies to the ventral embryonic epidermis. First, we show that interfaces between posterior (engrailed ON) and anterior (engrailed OFF) cells are required for pattern formation. Second, we provide evidence that Wingless could play the role of the morphogen, at least within part of the segmental pattern. We looked at the cuticular structures that develop after different levels of uniform Wingless activity are added back to unsegmented embryos (wingless- engrailed-). Because it is rich in landmarks, the T1 segment is a good region to analyse. There, we find that the cuticle formed depends on the amount of added Wingless activity. For example, a high concentration of Wingless gives the cuticle elements normally found near the top of the presumed gradient. Unsegmented embryos are much shorter than wild type. If Wingless activity is added in stripes, the embryos are longer than if it is added uniformly. We suggest that the Wingless gradient landscape affects the size of the embryo, so that steep slopes would allow cells to survive and divide, while an even distribution of morphogen would promote cell death. Supporting the hypothesis that Wingless acts as a morphogen, we find that these stripes affect, at a distance, the type of cuticle formed and the planar polarity of the cells. 相似文献
995.
PA Hofmann 《Canadian Metallurgical Quarterly》1993,19(7):235-246
BACKGROUND: In May 1991 Mount Clemens General Hospital (MCGH) began investigating the critical path method (CPM) as a tool for extending total quality management in clinical areas. In its search for guidelines on how to develop a critical path program, it found that other hospitals used a variety of approaches. These included employing case managers or outside consultants to develop programs or implementing prepurchased paths. Because these approaches often are difficult to customize for a specific institution and because MCGH wanted to use an internal team, none of these options seemed appropriate. With no definitive guidelines to follow, MCGH developed and implemented its own CPM. METHODS: The developmental process was composed of activities in nine primary categories: literature search, steering group, targeting strategy, paperwork design, gaining consensus, pilot program, preliminary findings, refine program, and full implementation. RESULTS: A pilot was performed to assess if the CPM would be beneficial. Six months into the pilot a preliminary review of coronary artery bypass graft paths was conducted. There were 44 patients in the study group (35 men, 9 women). Twenty-four patients were cared for before the critical path form was available. Preliminary findings indicated a lower rate of complications in patients cared for with the critical path form. The data revealed a 5% complication rate with the critical path compared to a 16.6% rate for those whose care was not guided by the form. In addition, patients with the path on their clipboards had an overall shorter length of stay than patients without the path. It is important to remember that these early data are based on the six-month pilot; they are not considered a conclusive research finding. NEXT STEPS: The next step in the CPM process is to examine other diagnoses that might benefit from a critical path approach. A steering committee composed of representatives from hospital administration, nursing, medical staff, quality assurance and risk management, and total quality management will act as the approval body for investigating and sanctioning other paths for development. CONCLUSION: The primary lesson learned at MCGH is that the CPM is most effective in an environment of communication and commitment. This approach allows clinic and nonclinic staff to talk about how their work influences each other's. CPM provides all caregivers with a common language and encourages everyone to look at the whole patient and the entire care process. The key message of success is: Get a group of people together who are motivated and empowered to move this exciting tool of the future through the necessary steps. 相似文献
996.
SK Collinson SL Liu SC Clouthier PA Banser JL Doran KE Sanderson WW Kay 《Canadian Metallurgical Quarterly》1996,169(1):75-80
The recombinant oncotoxin OLX-209 [e23(Fv)PE38KDEL] has been developed to target cancers with erbB-2 expression and is nearing a clinical trial. Important in clinical planning is the selection of patients on the basis of tumor expression of erbB-2. ErbB-2 gene amplification occurs in cancers of the breast, stomach, and ovary. Patients with these diseases and evident overexpression are candidates for OLX-209 therapy. In lung cancer, overexpression of erbB-2 is also frequent, but in most cases, it is not caused by gene amplification. This study demonstrates that OLX-209 has activity on lung cancer cells with varying levels of erbB-2 expression in the presence and absence of gene amplification. In vitro sensitivity of cell lines to OLX-209 is related to erbB-2 expression level. Normal bronchial epithelial cells were not sensitive. Effective treatment of lung cancer cell lines growing as xenografts in nude mice was shown with Calu-3 (a lung adenocarcinoma line with high levels of p185(erbB-2) caused by gene amplification) and three other lung adenocarcinomas (A549, NCI-H1466, and 201T) with lower levels of p185(erbB-2) and no gene amplification. The 201T cell line was isolated recently from a lung tumor with erbB-2 expression in the original tumor. The results of this study indicate that patients with erbB-2-positive, non-small cell lung cancer should be included in clinical trials of OLX-209. 相似文献
997.
RD Bolton MD Cooper JS Frank AL Hallin PA Heusi CM Hoffman GE Hogan FG Mariam HS Matis RE Mischke LE Piilonen VD Sandberg GH Sanders U Sennhauser R Werbeck RA Williams SL Wilson R Hofstadter EB Hughes MW Ritter D Grosnick SC Wright VL Highland J McDonough 《Canadian Metallurgical Quarterly》1988,38(7):2077-2101
998.
CG Knight LF Morton DJ Onley AR Peachey AJ Messent PA Smethurst DS Tuckwell RW Farndale MJ Barnes 《Canadian Metallurgical Quarterly》1998,273(50):33287-33294
The collagen type I-derived fragment alpha1(I)CB3 is known to recognize the platelet collagen receptor integrin alpha2beta1 as effectively as the parent collagen, although it lacks platelet-aggregatory activity. We have synthesized the fragment as seven overlapping peptides that spontaneously assemble into triple helices. On the basis of their capacity to bind purified alpha2 beta1 and the recombinant alpha2 A-domain, and their ability to support alpha2 beta1-mediated cell adhesion, we identified two peptides, CB3(I)-5 and -6, which contain an alpha2 beta1 recognition site. Synthesis of the peptide CB3(I)-5/6, containing the overlap sequence between peptides 5 and 6, allowed us to locate the binding site within the 15-residue sequence, GFP*GERGVEGPP*GPA (where P* represents hydroxyproline), corresponding to residues 502-516 of the collagen type I alpha1 chain. The Glu and Arg residues in the GER triplet were found to be essential for recognition since substitution of either residue with Ala caused a loss of alpha2 A-domain binding. By contrast, substitution of the Glu in GVE did not reduce binding, but rather enhanced it slightly. We were unable to detect significant recognition of alpha2 beta1 by the peptide CB3(I)-2 containing the putative alpha2 beta1 recognition sequence DGEA. Peptides CB3(I)-1 to -6, together with peptide CB3(I)-5/6, exhibited good platelet-aggregatory activity, in some cases better than collagen. However, peptide CB3(I)-7 was inactive, suggesting the presence of an inhibitory element that might account for the lack of aggregatory activity of the parent alpha1(I)CB3 fragment. 相似文献
999.
M Tsutsumi YC Tsai ML Gonzalgo PW Nichols PA Jones 《Canadian Metallurgical Quarterly》1998,17(23):3021-3027
We looked for p16/p19 deletion and p16 promoter methylation, as well as loss of 9p21 heterozygosity in pure squamous cell carcinomas (SCC), and in transitional cell carcinomas (TCC) of the bladder with SCC components. Homozygous deletion of p16/p19 was detected in 11 of 21 (52%) cases of pure SCCs and in three of ten (30%) cases of TCC with SCC. Three cases of TCC with SCC had p16/p19 deletion, hypermethylation of the p16 promoter, or LOH on 9p21 only in the SCC components, suggesting that these molecular alterations occurred preferentially in SCC. Interestingly, homozygous deletion of p16/p19 was observed in squamous metaplasia from bladder cancer patients (five of 11, 45%), showing that this change occurred in preneoplastic cells. On the other hand, p16/p19 deletions were not found in squamous metaplasias from non cancerous patients. Hypermethylation of the p16 promoter was observed in two of 14 tumors (14%) and none of seven metaplasias examined. These data suggest that: (a) p16/p19 deletion is associated with early carcinogenesis of SCC of the bladder, and squamous metaplasia of the bladder cancer patient has already sustained genetic changes found in cancer, and (b) genetic mosaicism occurs in cases of TCC with SCC, with the SCC component showing more frequent 9p21 alterations than the TCC component. 相似文献
1000.