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排序方式: 共有873条查询结果,搜索用时 15 毫秒
81.
Patty H Spruit Sabine Siesling Marloes AG Elferink Ernest JA Vonk Carel JM Hoekstra 《Radiation oncology (London, England)》2007,2(1):1-6
Background
To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.Methods
36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.Results
There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)Conclusion
Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone. 相似文献82.
83.
Paulo CJL Santos Renata AG Soares Diogo BG Santos Raimundo M Nascimento George LLM Coelho José C Nicolau José G Mill José E Krieger Alexandre C Pereira 《BMC medical genetics》2011,12(1):13
Background
Recent studies have reported the clinical importance of CYP2C19 and ABCB1 polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of CYP2C19 and ABCB1 polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population. 相似文献84.
Marrow stromal cells for cellular cardiomyoplasty: feasibility and potential clinical advantages 总被引:150,自引:0,他引:150
Wang JS Shum-Tim D Galipeau J Chedrawy E Eliopoulos N Chiu RC 《The Journal of thoracic and cardiovascular surgery》2000,120(5):999-1005
OBJECTIVES: Marrow stromal cells are mesenchymal stem cells able to differentiate into cardiomyocytes in vitro. We tested the hypothesis that marrow stromal cells, when implanted into myocardium, can undergo milieu-dependent differentiation and express cardiomyogenic phenotypes in vivo. METHODS: Isogenic adult rats were used as donors and recipients to simulate autologous transplantation. Marrow stromal cells isolated from donor leg bones were culture-expanded, labeled with 4;,6-diamidino-2-phenylindole, and then injected into the myocardium of the recipients. The hearts were harvested from 4 days to 12 weeks after implantation, and the implant sites were examined to identify the phenotypes of the labeled marrow stromal cells. RESULTS: Viable cells labeled with 4;, 6-diamidino-2-phenylindole can be identified in host myocardium at all time points after implantation. Implanted marrow stromal cells show the growth potential in a myocardial environment. After 4 weeks, donor cells derived from marrow stromal cells demonstrate myogenic differentiation with the expression of sarcomeric myosin heavy chain and organized contractile proteins. Positive staining for connexin 43 indicates the formation of gap junctions, which suggests that cells derived from marrow stromal cells, as well as native cardiomyocytes, are connected by intercalated disks. CONCLUSIONS: Different cell sources have been used as donor cells for cellular cardiomyoplasty. Our findings indicate that marrow stromal cells can also be used as donor cells. In an appropriate microenvironment they will exhibit cardiomyogenic phenotypes and may replace native cardiomyocytes lost by necrosis or apoptosis. Because marrow stromal cells can be obtained repeatedly by bone marrow aspiration and expanded vastly in vitro before being implanted or used as autologous implants, and because their use does not call for immunosuppression, the clinical use of marrow stromal cells for cellular cardiomyoplasty appears to be most advantageous. 相似文献
85.
Prof. Dr. rer. nat. E. Spörl N. Terai M. Haustein AG. Böhm F. Raiskup-Wolf L.E. Pillunat 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》2009,106(6):512-520
Aim
Several methods permit the measurement of geometric parameters of the cornea, but until now biomechanical conditions of the cornea have been ignored (e.g. in refractive corneal surgery). Besides the geometric condition, biomechanical properties of the cornea have been shown to influence applanation measurement of intra-ocular pressure (IOP) and epidemiological studies have identified corneal thickness as an independent risk factor for the development and progression of glaucoma. The aim of this investigation was to characterize the biomechanical properties of the cornea using the ocular response analyzer (ORA).Methods
The ocular response analyzer (ORA) is a new method available for non-contact measurement of the biomechanical properties of the cornea. We evaluated the reproducibility of measurements, the difference between static and dynamic factors and the impact of independent factors (e.g. IOP, age, CCT, swelling of the cornea) on 2,500 measurements of corneal hysteresis (CH) and corneal resistance factor (CRF).Results
In a large sample size we observed changes in CH and CRF after refractive surgery procedures (LASIK, UV-A cross-linking, keratoplasty) and in other corneal disorders (keratoconus, corneal dystrophies).Conclusions
CRF and CH changes may reflect structural changes of the cornea. Thus, the ORA provides valuable information for a better understanding and characterization of the biomechanical condition of the cornea, especially with regard to diseases such as keratoconus and glaucoma. 相似文献86.
AG Hamburg 《MedR Medizinrecht》2001,19(1):47-49
Ohne Zusammenfassung 相似文献
87.
AG Rüsselsheim 《MedR Medizinrecht》2006,24(7):435-436
Abstrakt 1. Hinsichtlich der Frage der Anerkennung einer Heilmethode kommt es nicht darauf an, ob eine Methode von der überwiegenden
Mehrheit der sogenannten Schulmediziner anerkannt wird, aber auch nicht, ob die betreffende Methode „therapieimmanent“, also
von denjenigen, die diese Methode entwickelt haben oder sie anwenden, als wirksam eingesch?tzt wird. Entscheidend ist vielmehr
auf die Anerkennung derjenigen Personen abzustellen, die sich von dritter Seite als Wissenschaftler in einem wissenschaftlichen
Verfahren mit der Frage der Wirksamkeit der betreffenden Methode auseinandergesetzt haben.
2. Der Wirkmechanismus der Bioresonanztherapie ist nach strengen naturwissenschaftlichen Untersuchungen nicht zu erkl?ren.
Diese Methode ist jedoch von der Hufelandgesellschaft, die sich aus 25 ?rztegesellschaften zusammensetzt, die allesamt auch
Naturheilverfahren betreiben, anerkannt. (Leits?tze des Bearbeiters) 相似文献
88.
89.
90.
Outbreak of ceftazidime resistance caused by extended-spectrum beta-lactamases at a Massachusetts chronic-care facility. 总被引:26,自引:16,他引:10 下载免费PDF全文
L B Rice S H Willey G A Papanicolaou A A Medeiros G M Eliopoulos R C Moellering Jr G A Jacoby 《Antimicrobial agents and chemotherapy》1990,34(11):2193-2199
During a 4-month period in late 1988, we isolated ceftazidime-resistant strains of Klebsiella pneumoniae and other members of the family Enterobacteriaceae from 29 patients at a chronic-care facility in Massachusetts. Ceftazidime resistance resulted from two distinct extended-spectrum beta-lactamases of the TEM type which efficiently hydrolyzed the cephalosporin: YOU-1 with a pI of 5.57 and YOU-2 with a pI of 5.2. Genes encoding these enzymes were present on different but closely related high-molecular-weight, multiple antibiotic resistance plasmids of the H12 incompatibility group and were transferable by conjugation in vitro. Agarose gel electrophoresis of extracts from clinical isolates indicated that this outbreak arose from plasmid transmission among different strains of the family Enterobacteriaceae rather than from dissemination of a single resistant isolate. Isolation rates of ceftazidime-resistant organisms transiently decreased after use of this drug was restricted, but resistant isolates continued to be recovered 7 months after empiric use of ceftazidime ceased. 相似文献