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11.

Background  

Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running.  相似文献   
12.
Adenosine deaminase complexing protein in cancer studies   总被引:3,自引:0,他引:3  
ADCP is a dimeric glycoprotein of about 200KD, for which the physiological role is still obscure. This protein occurs mainly in a membrane bound form in various human tissues. In this paper we review the current literature on ADCP in cancer studies. Soluble ADCP was described to be consistently decreased or absent in cancers of lung, liver, kidney and colon. These findings could not be confirmed by immunohistochemical and quantitative biochemical studies in a series of colorectal-, prostatic-, and renal carcinomas. Only in a third of these tumors a decrease could be demonstrated, whereas in the other cases unaltered or even increased amounts were observed. However, in virally transformed human fibroblasts a consistent decrease or complete absence of ADCP was seen, while primary fibroblasts were found to contain high amounts of this protein. Recently, the use of ADCP as a differentiation marker in colonic cancer has been advocated. Furthermore the presence of ADCP in the serum of renal adenocarcinoma patients was found to be indicative of a better chance of five year survival. These studies suggest that ADCP may be a differentiation marker useful for immunohistochemical characterization of colonic and renal carcinomas as well as a serum marker useful for follow-up studies of these types of cancer, analogous to CEA. Finally, ADCP has been found to be selectively expressed by certain T-cell subsets and henceforth may be useful in the studies on leukemias.  相似文献   
13.
Tongue and oropharynx: findings on MR imaging   总被引:6,自引:0,他引:6  
Ten healthy subjects and 44 patients with diseases of the tongue or oropharynx were studied with magnetic resonance (MR) imaging. Axial, coronal, and sagittal images with a thickness of 4 mm were obtained with a pixel size of 0.75 X 0.75 mm on a 256 matrix. Nineteen of the patients underwent computed tomography (CT). Nine of those patients later had surgery, and the specimens were obtained for organ sectioning. These three studies as well as clinical history and physical examination findings were correlated. MR imaging was equal to or better than CT in those patients having both examinations. However, neither CT nor MR allowed recognition of histologic features or detection of microscopic spread of disease. Direct coronal and sagittal imaging planes on MR imaging allowed visualization of intrinsic tongue musculature, not possible with CT; this was important in recognizing subtle tumor extension. For these reasons, MR is the imaging method of choice for studying diseases of the tongue and oropharynx.  相似文献   
14.
BACKGROUND: The administration of blood components from donors who subsequently develop Creutzfeldt-Jakob disease has raised the issue of blood as a possible vehicle for iatrogenic disease. STUDY DESIGN AND METHODS: We examined infectivity in blood components and Cohn plasma fractions in normal human blood that had been "spiked" with trypsinized cells from a scrapie-infected hamster brain, and in blood of clinically ill mice that had been inoculated with a mouse-adapted strain of human transmissible spongiform encephalopathy. Infectivity was assayed by intracerebral inoculation of the blood specimens into healthy animals. RESULTS: Most of the infectivity in spiked human blood was associated with cellular blood components; the smaller amount present in plasma, when fractionated, was found mainly in cryoprecipitate (the source of factor VIII) and fraction I+II+III (the source of fibrinogen and immunoglobulin); almost none was recovered in fraction IV (the source of vitamin-K-dependent proteins) and fraction V (the source of albumin). Mice infected with the human strain of spongiform encephalopathy had very low levels of endogenous infectivity in buffy coat, plasma, cryoprecipitate, and fraction I+II+III, and no detectable infectivity in fractions IV or V. CONCLUSION: Convergent results from exogenous spiking and endogenous infectivity experiments, in which decreasing levels of infectivity occurred in cellular blood components, plasma, and plasma fractions, suggest a potential but minimal risk of acquiring Creutzfeldt-Jakob disease from the administration of human plasma protein concentrates.  相似文献   
15.
BACKGROUND: The purpose of this study was to evaluate the criteria for assessing the appropriateness of red cell transfusions. The data were obtained by a computer search of all English-language literature from 1966 to October 1992. STUDY DESIGN AND METHODS: Nine studies were selected, which dated from 1986 to 1989 and employed explicit criteria evaluating the appropriateness of red cell transfusion in adults. The following data were abstracted from all studies: study design, timing, location, criteria for evaluating appropriateness, and rate of appropriate or inappropriate transfusions. RESULTS: Five studies evaluated transfusion appropriateness. Appropriateness rates ranged from 88 to 99 percent in three studies, and inappropriateness rates ranged from 0.3 to 57.3 percent in two studies. Four studies evaluated transfusion inappropriateness and reported inappropriateness rates of 18 to 55 percent. Substantial variation was found in the criteria for an appropriate or an inappropriate transfusion. Appropriateness rates did not depend upon characteristics of the study design, location, or timing of data collection. Restrictiveness in the criteria used to determine appropriateness and the use of additional implicit evaluation after an initial explicit review affected appropriateness rates. CONCLUSION: In the 1980s, high rates of inappropriate transfusion and low rates of appropriate transfusion were still reported. Appropriateness rates varied widely, in part because of marked variation in the criteria for an appropriate transfusion. Newly derived standards for an appropriate red cell transfusion, published in 1992, appear to provide a simple and objective means of evaluating the appropriateness of a transfusion. Appropriateness rates resulting from the application of these new standards have not yet been determined.  相似文献   
16.
Pheochromocytomas (PCCs) are rare tumors that arise from chromaffin tissue in the adrenal medulla, but can also occur in the abdomen outside the adrenals and are then called sympathetic paragangliomas (sPGLs). According to the literature, between 15 and 25% of apparently sporadic adrenal PCC and sPGL are caused by germline mutations in RET, von Hippel-Lindau disease (VHL), succinate dehydrogenase subunit B (SDHB), or subunit D SDHD. However, few studies have addressed the mutationfrequency of these candidate genes in selected subgroups of PCC andsPGL, such as bilateral adrenal PCC or extra-adrenal sPGL, and none have looked at somatic mutations by analyzing tumor tissue. Therefore, we have investigated the occurrence of germline and somatic mutations in RET, VHL, SDHB, and SDHD in comparatively large series of bilateral adrenal PCC (n = 33 patients) and sPGL (n = 26 patients), with the aim of determining the mutation frequency of each of these genes and to establish a genetic testing algorithm. Twenty-one RET, two VHL germline, and one SDHD mutations were found in the patients with bilateral adrenal PCC. In sPGL, one novel SDHB germline and one novel SDHB somatic mutation were observed. In addition, two SDHD germline mutations were found. We conclude that germline RET mutations are predominantly found in bilateral PCC, and that somatic and germline SDHB and SDHD mutations usually occur in sPGL, which has practical consequences for genetic testing algorithms. We suggest that sequential mutation analysis should be directed first at RET, followed by VHL and SDHD for patients with bilateral adrenal PCC at diagnosis, and at SDHB and SDHD for patients with sPGL.  相似文献   
17.
Only a few studies examined the effect of temozolomide (TMZ) in recurrent low-grade astrocytoma (LGA) after surgery, none of which included a homogeneous and sufficiently sized group of patients with progression after radiotherapy (RT). We evaluated a cohort of 58 patients treated with TMZ for progression after RT of a previous LGA and investigated the relation between outcome and mutations in the IDH1, IDH2, and TP53 genes, O6-methylguanine-methyltransferase (MGMT) promoter methylation, trisomy of chromosome 7, and loss of chromosomes 1p and 19q. All patients received first-line TMZ 200 mg/m2/day on days 1–5 every 4 weeks for a progressive LGA with a contrast-enhancing lesion on MRI after RT. Six months progression-free survival (PFS) was 67%, and the median overall survival was 14 months. An objective response was obtained in 54%. TP53 mutations and loss of chromosome 19q showed a borderline association with PFS, but none of the other molecular characteristics were correlated with the outcome to TMZ. Both a methylated MGMT promoter gene and IDH1 mutations were found in 86% of the tumor samples. A correlation was found between IDH1 mutations and MGMT promoter methylation (P < .001). Neither MGMT promoter methylation nor IDH1 mutations correlated with PFS, but the interval between the very first symptom of the LGA and the start of the TMZ was significantly longer in the patients with IDH1 mutations (P = .01) and a methylated MGMT promoter (P = .02). We conclude that MGMT promoter methylation and IDH1 mutations seem to predict survival from the time of diagnosis, but not PFS to TMZ.  相似文献   
18.
乙肝病毒和人乳头状瘤病毒分别是肝细胞癌和子宫颈癌的风险因素,针对这2种病毒感染的疫苗已在临床上成功用于癌症化学预防。分子靶向药物能够预防乳腺癌(雷洛昔芬与他莫昔芬)、大肠腺瘤(塞来昔布)和前列腺癌(非那雄胺)。然而,化学预防广泛应用于临床还不现实。分子靶标的深入研究将扩展化学预防的范围并使其个性化。  相似文献   
19.
Mistaken identity of widely used esophageal adenocarcinoma cell line TE-7   总被引:2,自引:0,他引:2  
Cancer of the esophagus is the seventh leading cause of cancer death worldwide. Esophageal carcinoma cell lines are useful models to study the biological and genetic alterations in these tumors. An important prerequisite of cell line research is the authenticity of the used cell lines because the mistaken identity of a cell line may lead to invalid conclusions. Estimates indicate that up to 36% of the cell lines are of a different origin or species than supposed. The TE series, established in late 1970s and early 1980s by Nishihira et al. in Japan, is one of the first esophageal cancer cell line series that was used throughout the world. Fourteen TE cell lines were derived from human esophageal squamous cell carcinomas and one, TE-7, was derived from a primary esophageal adenocarcinoma. In numerous studies, this TE-7 cell line was used as a model for esophageal adenocarcinoma because it is one of the few esophageal adenocarcinoma cell lines existing. We investigated the authenticity of the esophageal adenocarcinoma cell line TE-7 by xenografting, short tandem repeat profiling, mutation analyses, and array-comparative genomic hybridization and showed that cell line TE-7 shared the same genotype as the esophageal squamous cell carcinoma cell lines TE-2, TE-3, TE-12, and TE-13. In addition, for more than a decade, independent TE-7 cultures from Japan, United States, United Kingdom, France, and the Netherlands had the same genotype. Examination of the TE-7 cell line xenograft revealed the histology of a squamous cell carcinoma. We conclude that the TE-7 cell line, used in several laboratories throughout the world, is not an adenocarcinoma, but a squamous cell carcinoma cell line. Furthermore, the cell lines TE-2, TE-3, TE-7, TE-12, and TE-13 should be regarded as one single squamous cell carcinoma cell line.  相似文献   
20.
Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease of the biliary tree and a risk factor for development of cholangiocarcinoma (CCA). The pathogenesis of PSC-related CCA is largely unclear, although it is assumed that chronic inflammatory environment plays a pivotal role. We aimed to investigate the effect of inflammation-related cytokines in PSC on the proliferation rate of cancer cells. For this, the proliferation index in PSC-CCA and sporadic CCA was determined by Ki-67 immunohistochemistry. The percentage of Ki-67 positivity in cancer cells was significantly higher in PSC-CCA than in sporadic CCA (41.3% ± 5.7% vs 25.8% ± 4.1%; P = .038). To assess which cytokines in the inflammatory environment have the potential to stimulate cancer cell proliferation, patient-derived CCA organoids (CCAOs) were exposed to five cytokines related to PSC (Interleukin (IL)-1β, IL-6, IL-17A, interferon gamma and tumor necrosis factor alpha). Only IL-17A showed a significant stimulatory effect on cell proliferation in CCAOs, increasing organoid size by 45.9% ± 16.4% (P < .01) and proliferation rate by 38% ± 16% (P < .05). IL-17A immunohistochemistry demonstrated that PSC-CCA might express more IL-17A than sporadic CCA. Moreover, correlation analysis in sporadic CCA and PSC-CCA found a significant correlation between IL-17A expression and proliferation. In conclusion, tumor cell proliferation is increased in PSC-CCA cells compared with sporadic CCA cells. IL-17A increases CCA cell proliferation in vitro and may contribute to the high proliferation rate in PSC-CCA in situ. Therefore, IL-17A represents a new potential therapeutic target in (PSC-)CCA, to be tested in future trials.  相似文献   
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