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101.
102.
BACKGROUND: The diagnostic yield of EUS-guided FNA (EUS-FNA) of solid pancreatic masses is a potential benchmark for EUS-FNA quality, because the majority of EUS-FNA of solid pancreatic masses should be diagnostic for malignancy. OBJECTIVES: To determine the cytologic diagnostic rate of malignancy in EUS-FNA of solid pancreatic masses and to determine if variability exists among endoscopists and centers. DESIGN: Multicenter retrospective study. PATIENTS: EUS centers provided cytology reports for all EUS-FNAs of solid, noncystic, >or=10-mm-diameter, solid pancreatic masses during a 1-year period. MAIN OUTCOME MEASUREMENT: Cytology diagnostic of pancreatic malignancy. RESULTS: A total of 1075 patients underwent EUS-FNA at 21 centers (81% academic) with 41 endoscopists. The median number of EUS-FNA of solid pancreatic masses performed during the year per center was 46 (range, 4-177) and per endoscopist was 19 (range, 1-97). The mean mass dimensions were 32 x 27 mm, with 73% located in the head. The mean number of passes was 3.5. Of the centers, 90% used immediate cytologic evaluation. The overall diagnostic rate of malignancy was 71%, 95% confidence interval 0.69%-0.74%, with 5% suspicious for malignancy, 6% atypical cells, and 18% negative for malignancy. The median diagnostic rate per center was 78% (range, 39%-93%; 1st quartile, 61%) and per endoscopist was 75% (range, 0%-100%; 1st quartile, 52%). LIMITATIONS: Retrospective study, participation bias, and varying chronic pancreatitis prevalence. CONCLUSIONS: (1) EUS-FNA cytology was diagnostic of malignancy in 71% of solid pancreatic masses and (2) endoscopists with a final cytologic diagnosis rate of malignancy for EUS-FNA of solid masses that was less than 52% were in the lowest quartile and should evaluate reasons for their low yield.  相似文献   
103.
目的:探讨三维适形放疗结合锎(252Cf)中子腔内后装照射治疗中晚期食管癌的疗效、不良反应及晚期并发症。方法:92例中晚期食管癌患者全部采用三维适形放疗结合锎(252Cf)中子腔内后装照射治疗。三维适形放疗总剂量为45Gy-54Gy,分25-30次,5-6周完成;腔内照射3-4Gy/次,1次/周,共2-4次,总吸收剂量10Gy-16Gy。结果:治疗结束3个月进食梗阻缓解率为95%。近期疗效:完全缓解(CR)27%,部分缓解(PR)69.6%。1、2、3年局部控制率分别为82%、51%、32%;1、2、3年生存率分别为:78%、35%、18%;急性放射性食管炎发生率为54%;晚期食管狭窄发生率9%;食管穿孔发生率2%。结论:中晚期食管癌采用三维适形放疗结合锎(252Cf)中子腔内后装照射能够迅速而持久地缓解进食梗阻症状,提高局部控制率及生活质量,近期疗效显著,放疗不良反应未见明显增加。  相似文献   
104.
Interleukin-7 (IL-7) is a homeostatic cytokine for resting T cells with increasing serum and tissue levels during T cell depletion. In preclinical studies, IL-7 therapy exerts marked stimulating effects on T cell immune reconstitution in mice and primates. First-in-human clinical studies of recombinant human IL-7 (rhIL-7) provided the opportunity to investigate the effects of IL-7 therapy on lymphocytes in vivo. rhIL-7 induced in vivo T cell cycling, bcl-2 up-regulation, and a sustained increase in peripheral blood CD4(+) and CD8(+) T cells. This T cell expansion caused a significant broadening of circulating T cell receptor (TCR) repertoire diversity independent of the subjects' age as naive T cells, including recent thymic emigrants (RTEs), expanded preferentially, whereas the proportions of regulatory T (T reg) cells and senescent CD8(+) effectors diminished. The resulting composition of the circulating T cell pool more closely resembled that seen earlier in life. This profile, distinctive among cytokines under clinical development, suggests that rhIL-7 therapy could enhance and broaden immune responses, particularly in individuals with limited naive T cells and diminished TCR repertoire diversity, as occurs after physiological (age), pathological (human immunodeficiency virus), or iatrogenic (chemotherapy) lymphocyte depletion.  相似文献   
105.
目的 了解应用IHA、ELISA检测鼠疫F1抗体的一致性,评价方法的优劣,以便更好地制订鼠疫监测的方法及防治策略.方法 对广西鼠疫监测点隆林、西林县的犬血清使用IHA及ELISA两种试验方法,并进行一致性研究,评价IHA与ELISA方法的可靠性.结果 IHA检测鼠疫F1抗体阳性率为0,ELISA检测鼠疫F1抗体的总阳性率为4.4%(12/273);IHA与ELISA之间的一致性为95.6%,其Kappa值等于0,呈轻度一致.结论 间接血凝试验方法特异、操作简便是传统的鼠疫监测手段之一;酶联免疫吸附试验具有敏感性高、特异性强、操作简便等特点,且与间接血凝试验有轻度一致性,适宜在鼠疫监测中推广应用.  相似文献   
106.
107.
Development of CD8(+) T-cell responses targeting tumor-associated antigens after autologous stem cell transplantations (ASCTs) might eradicate residual tumor cells and decrease relapse rates. Because thymic function dramatically decreases with aging, T-cell reconstitution in the first year after ASCT in middle-aged patients occurs primarily by homeostatic peripheral expansion (HPE) of mature T cells. To study antigen-specific T-cell responses during HPE, we performed syngeneic bone marrow transplantations (BMTs) on thymectomized mice and then vaccinated the mice with peptides plus CpG-containing oligodeoxynucleotides (CpGs) in incomplete Freund adjuvant and treated the mice with systemic interleukin-2 (IL-2). When CD8(+) T-cell responses were measured ex vivo, up to 9.1% of CD8(+) T cells were specific for tumor-associated epitopes. These large T-cell responses were generated by synergism between CpG and IL-2. When we injected mice subcutaneously with tumor cells 14 days after BMT and then treated them with peptide + CpG-containing vaccines plus systemic IL-2, survival was increased and tumor growth was inhibited in an epitope-specific manner. Depletion of CD8(+) T cells eliminated epitope-specific antitumor immunity. This is the first report to demonstrate that CD8(+) T-cell responses capable of executing antitumor immunity can be elicited by CpG-containing vaccines during HPE.  相似文献   
108.
OBJECT: Delayed cerebral ischemia is a major cause of morbidity and death following aneurysmal subarachnoid hemorrhage and requires timely intervention for a successful outcome to be achieved. In this study the investigators compared the commonly used Fisher scale with 2 newer radiographic scales for the prediction of vasospasm, delayed infarction, and poor outcome. METHODS: This was a single-center, retrospective cohort study involving 271 consecutive patients with a ruptured cerebral aneurysm. Without knowledge of subsequent events, admission CT scans were each assigned scores by using 3 different grading schemes: the Fisher, modified Fisher, and Claassen scales. For each of the scales, the relationship between an increasing score and the risk of later complications was assessed in univariate and multiple logistic regression analyses. RESULTS: With the Fisher scale, the risk of complications was relatively high when the score was 3, but not for other scores. In contrast, using the other scales, there was a more linear relationship between a rising score and the frequency of complications. This was particularly true for the modified Fisher scale, in which each stepwise increase was associated with an escalating risk of vasospasm, delayed infarction, and poor prognosis. Kappa scores measuring interobserver variability among 4 CT readers were also slightly better with the newer scales. CONCLUSIONS: Although the modified Fisher and Claassen scales have yet to be prospectively validated, the authors' findings suggest that the clinical performance of these systems is superior to that of the Fisher scale.  相似文献   
109.
110.
Twelve of 19 patients with myeloproliferative disorders showed a decrease of absence of the largest multimers of plasma von Willebrand factor (vWF) that correlated with elevated platelet counts but not with leukocyte counts. This suggested that platelets, rather than leukocytes, may be associated with the pathogenesis of the acquired vWF abnormality seen in these patients. To examine the hypothesis further, we studied 12 patients with reactive thrombocytosis after splenectomy. Increased platelet count (> 5 x 10(11)/L) after splenectomy was associated with vWF abnormalities indistinguishable from those detected in patients with myeloproliferative disorders. Accordingly, there was an inverse correlation between proportion of large vWF multimers and platelet, but not leukocyte, number: normalization of the platelet count was accompanied by restoration of a normal vWF multimeric pattern. These findings suggest that an increase in the number of platelets circulating in blood may favor the adsorption of larger vWF multimers onto the platelet membrane, resulting in their removal from the circulation and subsequent degradation.  相似文献   
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