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41.
Reports of close associations between recurring chromosomal abnormalities and the clinical behavior of acute nonlymphocytic leukemia (ANLL) have stimulated efforts to define this disease in cytogenetic terms. Here we report on the leukemic cell karyotypes of 155 children with ANLL who were treated from 1980 to 1987 in consecutive programs of chemotherapy at this institution. Of 121 cases with adequate banding, 20% were normal, 30% had miscellaneous clonal abnormalities, and 50% were classified into known cytogenetic subgroups: inv(16)/del(16q) (n = 15), t(8; 21) (n = 14), t(15;17) (n = 9), t(9;11) (n = 9), t(11;V)/del(11q) (n = 7) and -7/del(7q) (n = 6). The inv(16)/del(16q) cases showed a nearly equal distribution of myelocytic and monocytic French-American-British (FAB) subtypes; only four of these patients presented with M4Eo morphology. Despite a 100% remission induction rate, patients with inv(16)/del(16q)-positive ANLL fared no better overall than the entire group; only 40% of this subgroup were event-free survivors at 2 years from diagnosis (P = .23). Patients with inv(16)/del(16q) frequently had CNS involvement at diagnosis (eight of 15) or initially relapsed in this site (three of eight). Event-free survival (EFS) was clearly superior for young patients with FAB M5 leukemia and the t(9;11) (P = .041). These patients were clinically indistinguishable from others with the FAB disease subtype, yet their responses to etoposide-containing therapies were noteworthy. By contrast, children with structural abnormalities involving 11q23, other than t(9;11), were infants (median age, 6 months) with FAB M4 or M5 leukemia, hyperleukocytosis, and frequent coagulation abnormalities. Patients with such changes [t(11;V) or del(11q)] relapsed early during postremission therapy: none remained disease-free more than 16 months from diagnosis. Because of resistant leukemia, patients with monosomy 7/del(7q) had a poor remission induction rate (17%; P = .0015); patients with the t(15;17) were also poor responders to induction therapy (44%; P = 0.02) because of hemorrhagic deaths. These results identify several cytogenetic subtypes of pediatric ANLL that may represent unique disease processes for which more effective early cytoreduction [-7/del(7q), t(11;V)], better supportive care measures [t(15;17)], or more effective CNS prophylaxis [inv(16)/del(16q)] would be warranted.  相似文献   
42.
Twenty-four (5.7%) of 424 children with newly diagnosed acute lymphoblastic leukemia (ALL) were found to have blast cells that expressed HLA-DR antigens but not the common ALL antigen (CALLA), E-rosette receptors, T-cell antigens, or cytoplasmic or surface immunoglobulins. Each of the eight cases tested expressed the B-cell associated antigen B4, but not B1 or B2 antigen. Myeloid-associated antigens were not present in any of the 10 cases tested. By comparison with common (CALLA+ B-cell precursor) ALL, patients having this immunophenotype were more likely to be children less than 2 yr of age (p less than 0.001), to have higher initial leukocyte counts (p less than 0.001), and to have blast cells with a DNA index less than 1.16 (p = 0.05), a pseudodiploid karyotype (p = 0.01) and a chromosomal translocation (p = 0.003). The presence of any chromosomal translocation in these CALLA- ALL was related to measures of increased leukemic cell burden including higher leukocyte counts, larger liver and spleen sizes and higher serum lactic dehydrogenase levels. While the patients were entered into several treatment arms of two protocols, the CALLA- cases appeared to have lower remission rate (p = 0.06) and shorter event-free survival time (p = 0.05) than did those with common ALL. The association with clinical and laboratory features of known adverse prognostic significance provides some explanation for the poor treatment outcome of CALLA- ALL.  相似文献   
43.
We studied the organization of immunoglobulin (Ig) genes and the beta-chain gene of the T cell receptor (TCR) along with the clinical features, immunophenotypes, and karyotypes of 14 children with acute leukemia at diagnosis and relapse. The median time to relapse was 23 months. Eleven children had identical gene rearrangement patterns at diagnosis and relapse. All three patients whose blast cells showed variations in gene rearrangement patterns between diagnosis and relapase also demonstrated a change in the immunophenotype: one from cALLA+ to cALLA- B precursor cell ALL; one from T-ALL to AML; and one showed a marked increase in myeloid characteristics at relapse. Blast cells from these three patients at relapse showed the presence of chromosomal translocations involving 11q23; for two patients, this involved replacement of the original karyotype. We conclude that while most relapses are the result of reemergence of the original clone, new clones that differ in immunophenotype, karyotype, and gene rearrangement are occasionally present at relapse. Relapses may also occur in which the original clone has undergone major changes in gene expression and arrangement of the Ig heavy chain genes in the absence of karyotypic replacement.  相似文献   
44.
FG K?ln 《MedR Medizinrecht》2008,26(11):690-694
Abstrakt  1. ?sthetische Operationen unterliegen der Umsatzsteuerpflicht. 2. Ums?tze aus der T?tigkeit als Arzt sind nur dann umsatzsteuerfrei, wenn sie der Diagnose, Behandlung und Heilung von Krankheiten oder Gesundheitsst?rungen dienen.  相似文献   
45.
Increased Rho kinase (ROCK) activity contributes to smooth muscle contraction and regulates blood pressure homeostasis. We hypothesized that potent and selective ROCK inhibitors with novel structural motifs would help elucidate the functional role of ROCK and further explore the therapeutic potential of ROCK inhibition for hypertension. In this article, we characterized two aminofurazan-based inhibitors, GSK269962A [N-(3-{[2-(4-amino-1,2,5-oxadiazol-3-yl)-1-ethyl-1H-imidazo[4, 5-c]pyridin-6-yl]oxy}phenyl)-4-{[2-(4-morpholinyl)ethyl]-oxy}benzamide] and SB-7720770-B [4-(7-{[(3S)-3-amino-1-pyrrolidinyl]carbonyl}-1-ethyl-1H-imidazo[4,5-c]pyridin-2-yl)-1,2,5-oxadiazol-3-amine], as members of a novel class of compounds that potently inhibit ROCK enzymatic activity. GSK269962A and SB-772077-B have IC50 values of 1.6 and 5.6 nM toward recombinant human ROCK1, respectively. GSK269962A also exhibited more than 30-fold selectivity against a panel of serine/threonine kinases. In lipopolysaccharide-stimulated monocytes, these inhibitors blocked the generation of inflammatory cytokines, such as interleukin-6 and tumor necrosis factor-alpha. Furthermore, both SB-772077-B and GSK269962A induced vasorelaxation in preconstricted rat aorta with an IC50 of 39 and 35 nM, respectively. Oral administration of either GSK269962A or SB-772077-B produced a profound dose-dependent reduction of systemic blood pressure in spontaneously hypertensive rats. At doses of 1, 3, and 30 mg/kg, both compounds induced a reduction in blood pressure of approximately 10, 20, and 50 mm Hg. In addition, administration of SB-772077-B also dramatically lowered blood pressure in DOCA salt-induced hypertensive rats. SB-772077-B and GSK269962A represent a novel class of ROCK inhibitors that have profound effects in the vasculature and may enable us to further evaluate the potential beneficial effects of ROCK inhibition in animal models of cardiovascular as well as other chronic diseases.  相似文献   
46.
ObjectivesTo systematically review and synthesize the evidence on physical activity and sedentary behavior during and after hospitalization.Data SourcesElectronic databases and reference lists of relevant articles were searched from 2000 to April 2020.Study SelectionStudies which continuously monitored physical activity and/or sedentary behavior in hospitalized adults across 2 settings (ie, without a break in measurement between settings). Monitoring could occur from an acute to a subacute or rehabilitation hospital setting, an acute setting to home, or from a subacute or rehabilitation setting to home.Date ExtractionData extraction and methodological quality assessments were independently performed by 2 reviewers using standardized checklists.Data SynthesisA total of 15 of the 5579 studies identified were included. The studies were composed of heterogenous patient populations. All studies monitored patients with either an accelerometer and/or pedometer and reported a variety of measures, including steps per day, sedentary time, and activity counts. The majority of studies (12 of 15) showed that patients engaged in 1.3 to 5.9 times more physical activity and up to 67% less daily sedentary behavior at home after discharge from acute or subacute settings.ConclusionsPatients engaged in more physical activity and less sedentary behavior at home compared to both the acute and subacute hospital settings. This may reflect the natural course of recovery or the effect of setting on activity levels. Enabling early discharge home through the implementation of home-hospitalization models may result in increased patient physical activity and reduced sedentary behavior. Further experimental studies are required investigating the effect of home-based models of care on physical activity and sedentary behavior.  相似文献   
47.
目的:应用高分辨率荧光显微成像系统采集细胞器探针图像,并与激光共聚焦显微成像系统进行对比。方法:实验于2003-05/2004-01在解放军总医院完成。①实验材料:鼠肺毛细血管内皮细胞株(1H11)由上海复旦张江生物公司提供;荧光探针Rhodamine-123,Lucifer Yellow,DiOC6[3],BODIPY(美国Sigma公司)。②细胞培养及荧光探针染色:细胞培养采用含体积分数为0.2胎牛血清的低糖DMEM培养基,密度5×107L-1。选择Rhodamine-123作为细胞线粒体特异性荧光探针,选择DiOC6[3]作为细胞内质网特异性荧光探针,选择BODIPY作为细胞高尔基体特异性荧光探针,选择Lucifer Yellow作为细胞溶酶体探针。前3个探针在完全避光条件下与培养的细胞共同孵育0.5h,后者则共同孵育15h。③高分辨率荧光成像系统的图像采集:线粒体荧光图像采集,选取经Rhodamine-123共孵育完成的细胞,选择激发滤色镜为BP460-490,吸收滤色镜为BA515,分光镜为DM500,另加一绿通道液晶滤光片,激发出Rhodamine-123的荧光。电荷耦合器件采集图像并送入计算机。重复上述步骤,采用DiOC6[3]标记内质网,BODIPY标记高尔基体,Lucifer Yellow标记细胞溶酶体,激发条件同Rhodamine-123。分别采集同一视野靶细胞DiOC6[3]、BODIPY或Lucifer Yellow的荧光图像,完成全部图像采集并储存在计算机中。④激光共聚焦显微成像系统的图像采集:选择经4种探针染色的靶细胞,使用氩离子激光器在488nm激发Rhodamine-123,Rhodamine-123荧光通过配置有530/60-G发射滤光片的通道1探测。重复上述步骤,在488nm激发DiOC6[3]和BODIPY,在457nm激发Lucifer yellow,3种荧光均由通道1探测,后2个探针的发射滤光片的配置为515/30-G,DiOC6[3]选择530/60-G。由光电倍增管接收信号并传输入计算机成像。结果:①高分辨率荧光成像系统所采集图像,靶细胞中由荧光探针Rhodamine-123染色的线粒体呈多个典型的小棒状或卵圆状,聚集在核周;Lucifer yellow染色的溶酶体呈多个非对称球型,在胞浆内随机分布,颗粒尺寸通常大于线粒体;荧光探针DiOC6[3]着色的内质网占据胞浆的很大空间,以囊状聚集为特征;BODIPY特异性地结合在高尔基体上,荧光图像显示围绕在细胞核周围呈条索状。②与高分辨率荧光成像系统比较,激光共聚焦显微成像系统所采集的图像其荧光强度基本相同,但分辨率低、细节显示模糊、胞浆中细胞器的准确分布信息和形态特征显示效果欠佳。结论:两种荧光显微成像系统均可采集到细胞器探针的荧光图像。但高分辨率荧光成像系统采集的荧光图像具有细节清晰、分辨度高、准确显示胞浆中细胞器的分布信息和形态特征等优点。  相似文献   
48.
49.
The purpose of this study was to determine if discrepancies exist between upright and inverted seated positions in isometric maximal voluntary contraction (MVC) elbow flexor force, MVC force produced in the first 100 ms (F100), MVC rate of force development, electromyographic (EMG) activity of the biceps and triceps as well as heart rate and blood pressure. The results showed significantly (p < 0.01) higher MVC force (543.6 ± 29.6 vs. 486.5 ± 23.0 N), F100 (328.3 ± 94.5 vs. 274.6 ± 101.8 N), rate of force development (p = 0.003) (1,851.9 ± 742.2 vs. 1,591.0 ± 719.6 N s−1) and biceps brachii EMG activity (48%, p < 0.01) in the upright versus inverted condition. There were relatively greater co-contractions with the inverted position (p < 0.01) due to the lack of change in triceps’ EMG and the substantial decrease in biceps’ EMG. There were no significant changes in trunk EMG activity. With inversion, there were significant decreases in heart rate (16.8%), systolic (11.6%) and diastolic (12.1%) blood pressures (p < 0.0001). These results illustrate decrements in neuromuscular performance with an inverted seated posture which may be related to an altered sympathetic response.  相似文献   
50.
The transient receptor potential (TRP) vanilloid subtype 4 (V4) is a nonselective cation channel that exhibits polymodal activation and is expressed in the endothelium, where it contributes to intracellular Ca2+ homeostasis and regulation of cell volume. The purpose of the present study was to evaluate the systemic cardiovascular effects of GSK1016790A, a novel TRPV4 activator, and to examine its mechanism of action. In three species (mouse, rat, and dog), the i.v. administration of GSK1016790A induced a dose-dependent reduction in blood pressure, followed by profound circulatory collapse. In contrast, GSK1016790A had no acute cardiovascular effects in the TRPV4-/- null mouse. Hemodynamic analyses in the dog and rat demonstrate a profound reduction in cardiac output. However, GSK1016790A had no effect on rate or contractility in the isolated, buffer-perfused rat heart, and it produced potent endothelial-dependent relaxation of rodent-isolated vascular ring segments that were abolished by nitric-oxide synthase (NOS) inhibition (N-nitro-L-arginine methyl ester; L-NAME), ruthenium red, and endothelial NOS (eNOS) gene deletion. However, the in vivo circulatory collapse was not altered by NOS inhibition (L-NAME) or eNOS gene deletion but was associated with (concentration and time appropriate) profound vascular leakage and tissue hemorrhage in the lung, intestine, and kidney. TRPV4 immunoreactivity was localized in the endothelium and epithelium in the affected organs. GSK1016790A potently induced rapid electrophysiological and morphological changes (retraction/condensation) in cultured endothelial cells. In summary, inappropriate activation of TRPV4 produces acute circulatory collapse associated with endothelial activation/injury and failure of the pulmonary microvascular permeability barrier. It will be important to determine the role of TRPV4 in disorders associated with edema and microvascular congestion.  相似文献   
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