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81.
82.
We studied 17 patients with moderate to mild type I von Willebrand's disease (vWd) and correlated the bleeding time with the plasma von Willebrand factor antigen (vWf Ag), the plasma vWf activity (ristocetin cofactor), the platelet vWf Ag, and the platelet vWf activity. We found an excellent correlation between the bleeding time and the platelet vWf activity and, to a lesser extent, between the bleeding time and the platelet vWf Ag. The length of the bleeding time was inversely proportional to the level of the platelet vWf (P less than .001) or, to a lesser extent, the platelet vWf Ag (P less than .05). The plasma vWf Ag and activity did not correlate significantly with the bleeding time. These studies indicate that the platelet vWf is one of the important bleeding time factors in type I vWd and that the platelet vWf plays an important role in the early steps of hemostasis.  相似文献   
83.
The Unified Huntington's Disease Rating Scale (UHDRS) adequately measures decline in patients at early and moderate stages of Huntington's disease (HD). In advanced patients, floor effects hamper the evaluation, thus calling for an adjusted scale. We designed the UHDRS‐For Advanced Patients (UHDRS‐FAP), in order to improve longitudinal assessment of patients at advanced disease stage. Sixty‐nine patients with a Total Functional Capacity (TFC) ≤ 5 were recruited in France and in the Netherlands. Among them, 45 patients were followed longitudinally (mean 1.6 ± 1.2 years) with the UHDRS‐FAP; 30 were also assessed with the UHDRS. Cross‐sectional analyses evaluated psychometric properties and interrater reliability of the scale. Longitudinal analyses evaluated the sensitivity to decline compared to the UHDRS. Internal consistency was higher for motor and cognitive scores than for somatic and behavioral scores (0.84, 0.91, 0.70, and 0.49, respectively). Interrater reliability was ≥ 0.88 in all scores. The somatic score, specific to the UHDRS‐FAP, declined over time, as well as motor and cognitive performance with both scales. Although performance with the 2 scales correlated, the UHDRS‐FAP appeared more sensitive to change and was the only scale that detected decline in patients with a TFC ≤ 1. Neither scale detected a significant decline in behavioral scores. The UHDRS‐FAP is reliable and more sensitive to change than the original UHDRS for cognitive and motor domains. It offers items relevant for daily care. Behavioral scores tended to decline but this may reflect the decline in the communicative abilities of the patients. © 2013 International Parkinson and Movement Disorder Society  相似文献   
84.
The Unified Huntington's Disease Rating Scale (UHDRS) adequately measures decline in patients at early and moderate stages of Huntington's disease (HD). In patients with advanced HD, floor effects hamper the evaluation, thus calling for an adjusted scale. We designed the UHDRS‐For Advanced Patients (UHDRS‐FAP) to improve longitudinal assessment of patients at the advanced disease stage. Sixty‐nine patients with a Total Functional Capacity score ≤ 5 were recruited in France and the Netherlands. Among them, 45 patients were followed longitudinally (mean ± standard deviation, 1.6 ± 1.2 years) with the UHDRS‐FAP; 30 patients also were assessed with the UHDRS. In cross‐sectional analyses, the psychometric properties and inter‐rater reliability of the scale were evaluated. Longitudinal analyses were used to evaluate the sensitivity to decline of the UHDRS‐FAP compared with the UHDRS. Internal consistency was higher for motor (0.84) and cognitive (0.91) scores than for somatic (0.70) and behavioral (0.49) scores. Inter‐rater reliability was ≥ 0.88 for all scores. The somatic score, which was specific to the UHDRS‐FAP, declined over time along with motor and cognitive performance on both scales. Although performance with the two scales was correlated, the UHDRS‐FAP appeared to be more sensitive to change and was the only scale that detected decline in patients with a Total Functional Capacity score ≤ 1. Neither scale detected a significant decline in behavioral scores. The results indicate that the UHDRS‐FAP is reliable and more sensitive to change than the original UHDRS for cognitive and motor domains. It offers items that are relevant for daily care. Behavioral scores tended to decline, but this may reflect the decline in patients' communicative abilities. © 2013 International Parkinson and Movement Disorder Society  相似文献   
85.
 目的  评价色胺酮衍生物吲哚胺2,3-双加氧酶 (indoleamine 2,3-dioxygenase,IDO)的抑制活性,并研究其作为 IDO 抑制剂的抗肿瘤作用。方法  采用基因工程手段表达、纯化重组人 IDO (rhIDO),建立 IDO 活性检测体系;以色胺酮衍生物作为对象,进行 IDO 抑制活性初筛,对抑制类型、半数抑制浓度以及抑制常数进行测定;构建高表达人 IDO 的 pcDNA3.1(+) hIDO 转染 HEK 293 细胞,评价色胺酮衍生物在细胞水平上的 IDO 抑制活性;采用 MTT 比色法考察色胺酮衍生物3对人非小细胞肺癌A549细胞的生长抑制作用。结果  6个被测色胺酮衍生物均具有IDO抑制活性,且细胞水平上的抑制效力高于酶活水平,抑制效力均优于目前通用的IDO抑制剂1 甲基色氨酸(1-methyl-tryptophan,1-MT)。色胺酮衍生物 3 作为最强的 IDO 抑制剂,其Ki值为 0.161 μmol/L。MTT 实验结果显示,色胺酮衍生物3 显著抑制 A549 细胞生长,IC50 为 8.77 μmol/L。结论  色胺酮衍生物是一类新型高效的 IDO 抑制剂,在体外对 A549 细胞具有较强的抗肿瘤活性。  相似文献   
86.
 目的 采用人结肠腺癌细胞系(human colon adenocarcinoma cell line) Caco-2单细胞层模型观察促红细胞生成素(erythropoietin,EPO)对叶酸跨膜转运的影响。方法 采用Caco-2单层细胞模型,观察不同剂量EPO (0.3、1、3 U/mL)处理对叶酸在摄取与外排双向转运方面的影响。通过real time-PCR与Western blot观察EPO处理对质子偶联的叶酸转运体(proton coupled folate transporter,PCFT)、还原叶酸载体(reduced folate carrier,RFC)以及多药耐药相关蛋白2 (multidrug resistance-associated protein 2,MRP2)表达的影响。结果 EPO在剂量0.3~3 U/mL范围内可剂量依赖地增加叶酸在摄取方向的转运,增幅分别为31.6%、61.5%和120.5%。高剂量EPO(3 U/mL)对叶酸在外排方向的转运也具有促进作用,增幅为56.9%,而中低剂量EPO (1、0.3 U/mL)对叶酸外排无明显作用。叶酸转运体PCFT、RFC及MRP2均受EPO影响而表达上调,并呈剂量依赖和时间依赖关系。结论 EPO可上调叶酸的摄取并呈剂量依赖关系,高剂量EPO对叶酸的摄取与外排具有双向促进作用。  相似文献   
87.
Although gastrointestinal stromal tumors(GISTs)are rare,with an incidence of 1/100000 per year,they are the most common sarcomas in the peritoneal cavity.Despite considerable progress in the diagnosis and treatment of GIST,about half of all patients are estimated to experience recurrence.With only two drugs,sunitinib and regorafenib,approved by the Food and Drug Administration,selecting treatment options after imatinib failure and coordinating multidisciplinary care remain challenging.In addition,physicians across the Middle East face some additional and unique challenges such as lack of published local data from clinical trials,national disease registries and regional scientific research,limited access to treatment,lack of standardization of care,and limited access to mutational analysis.Although global guidelines set a framework for the management of GIST,there are no standard local guidelines to guide clinical practice in a resource-limited environment.Therefore,a group of 11 experienced medical oncologists from across the Gulf and Levant region,part of the Rare Tumors Gastrointestinal Group,met over a period of one year to conduct a narrative review of the management of GIST and to describe regional challenges and gaps in patient management as an essential step to proposing local clinical practice recommendations.  相似文献   
88.
89.
The submolecular basicities of 21 immuno-modulating, thymopoietin-type di-, tri-, and tetrapeptides were studied and characterized in terms of group constants and partial microconstants. All compounds were derivatives of the H-Arg-Lys-Asp-OH tripeptide. Modifications within four covalent bonds of the basic site (esterification, acylation, curtailment or addition at C-terminal end, exchange of amino acids) cause significant changes in the scheme of protonation and in the individual basicity of proton binding sites. Configurational changes of the component amino acids, however, do not cause significantly different basicities in the diastereomers.  相似文献   
90.
Hemorrhagic intracranial malignant neoplasms: spin-echo MR imaging   总被引:2,自引:0,他引:2  
Twelve patients with 15 separate, spontaneously hemorrhagic, intracranial malignant lesions (seven primary gliomas, eight metastatic lesions) were examined with spin-echo magnetic resonance imaging at 1.5 T, and with computed tomography. The signal intensity patterns of these lesions, as seen on both short repetition time (TR)/short echo time (TE) and long-TR/long-TE spin-echo pulse sequences, were compared with the previously described appearance at 1.5 T of non-neoplastic intracerebral hematomas. The images of hemorrhagic intracranial malignancies showed notable signal heterogeneity, often with identifiable nonhemorrhagic tissue corresponding to tumor; diminished, irregular, or absent hemosiderin deposition; delayed hematoma evolution; and pronounced or persistent edema, compared with non-neoplastic hematomas. The demonstration of these characteristics in the appropriate clinical setting may suggest malignancy as the cause of an intracranial hematoma.  相似文献   
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