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71.
Logan PM 《Irish journal of medical science》2004,173(1):7-8
Background Lung cancer is the most common cause of cancer-related death in Ireland. There are few complete data sets available as to
the stage and cell type of lung cancers at time of presentation in Ireland.
Aim To audit the lung cancers presenting to a large Dublin teaching hospital over a 12-month period.
Method Prospective evaluation of all lung tumours presenting to our institution over a consecutive 12-month period.
Results One hundred and ninety-eight lung cancers presented over the study period. There were 34 cases of small cell carcinoma and
150 cases of non-small cell carcinoma (NSCC). Fourteen patients were too ill or compromised at time of presentation for tissue
confirmation. The most common cell type was squamous carcinoma. Eighty-four per cent of the NSCCs were either stage 3 or 4
at presentation.
Conclusion Most lung cancers present late in the time course of the disease. Distribution of cell type and location are similar in Ireland
and other developed countries. 相似文献
72.
OBJECTIVE: The purpose of this study was to determine whether the label attached to the hearing aid being presented would bias outcome measures towards newer technological designs. DESIGN: Two groups of subjects participated in this investigation. The groups were matched for age, gender, previous hearing aid experience, degree and configuration of hearing loss. Group A wore each of two digital hearing aids for 1 mo; Group B wore the same digital hearing aid for 2 mo, but the subjects were given the impression they were changing hearing aids after 1 mo. In each group the subjects were told that one of the months they were wearing a "digital" hearing aid and one of the months they were wearing a "conventional" hearing aid. Outcome measures consisted of a number of behavioral speech perception tasks and self-report measures, each completed at the onset and after 1 mo use with the hearing aids. RESULTS: Labeling effects were observed for many of the outcome measures. Using a mixed-model factorial analysis of variance to control for irrelevant variables and to explore interaction terms, prejudice (digital versus conventional labeling) was treated as a within-subject factor while the subject group (A or B) and clinician were treated as between-subject factors. Although only the APHAB RV and BN scales showed significant labeling effects on their own, the group of tests used in this study showed a significant labeling effect as a whole (p < 0.01). The total influence of labeling and related interaction terms indicated labeling-related effects accounted for 2 to 32% of the variance in individual outcome measures. DISCUSSION: The results of this investigation indicate a need for double-blinding in hearing aid research aimed at assessing the effectiveness of newer technologies, as well as a need for clinicians to critically evaluate the research describing the potential advantages of certain circuit options. 相似文献
73.
OBJECTIVE: To measure hearing aid performance using circuitry representative of the major eras of technological advancement during the 20th century. DESIGN: Twenty subjects with audiometric profiles consistent with hearing aid candidacy were fit with each of seven hearing aids. No directional microphones were used and binaural benefit was not assessed. Each hearing aid was fit to the strategy or fitting scheme of the era, or that which was intended by the presenting manufacturer. Electroacoustic and/or real ear measures of gain, output, bandwidth, and distortion were obtained. Objective outcome measures assessing speech perception in backgrounds of noise were obtained. Subjective outcome measures of sound quality and ease of listening were obtained in the laboratory and in real life settings. RESULTS: Electroacoustic and real ear measures indicate that gain and bandwidth have increased, and output and distortion have decreased with current electronic aids. Speech perception ability across the different outcome measures showed significantly poorer performance with the body and linear hearing aids when input levels were high; when input levels were low, outcome measures with hearing aids using a dynamic range compression were not negatively affected. At the most adverse signal to noise ratios, none of the hearing aids was shown to be superior. Measured bandwidth did not correlate highly with speech perception ability for any of the objective outcome measures used. For the subjective measures of sound quality done in a blinded manner, no significant differences were found across different listening situations for current hearing aids. CONCLUSIONS: The two most important factors for aided speech perception appear to be the audibility and distortion of the signal. No current compression scheme proved superior with the outcome measures used in this investigation. 相似文献
74.
75.
Ocular MR imaging and spectroscopy: an ex vivo study 总被引:2,自引:0,他引:2
Gomori JM; Grossman RI; Shields JA; Augsburger JJ; Joseph PM; DeSimeone D 《Radiology》1986,160(1):201-205
Six eyes, freshly enucleated because of choroidal melanoma, were imaged on a 1.4-T superconducting magnetic resonance (MR) imaging system, and relaxation times were calculated for various parts of the eye. Unfixed fresh tissue samples were obtained for nuclear magnetic resonance spectroscopy (NMRS) on a variable-field (0.19-1.4 T) resistive unit. Detailed ocular anatomy was demonstrated. The NMRS relaxation times correlated with the MR imaging intensity patterns. The sensitivity of MR imaging to states of hydration provides an excellent window for appreciation of ocular anatomy. 相似文献
76.
RS de Vreeze D de Jong IH Tielen HJ Ruijter PM Nederlof RL Haas F van Coevorden 《Modern pathology》2009,22(2):223-231
Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum. 相似文献
77.
78.
Femoral capital osteonecrosis: MR finding of diffuse marrow abnormalities without focal lesions 总被引:13,自引:0,他引:13
Six painful hips in five patients were examined with magnetic resonance (MR) imaging and were found to have diffuse signal abnormalities in the marrow of the femoral head and neck, which extended into the intertrochanteric area in five cases. The abnormal regions were low in signal intensity on images obtained with a short repetition time (TR) and a short echo time (TE) and were isointense or hyperintense on long TR/TE images--findings that have been attributed by others to bone marrow edema. Edema was also seen in marrow just above the acetabulum in two cases. No focal abnormalities characteristic of osteonecrosis were seen. Osteonecrosis was subsequently shown to be present in all six femoral heads at core biopsy (three cases) or by subsequent development of focal MR abnormalities reported to be highly specific for osteonecrosis (three cases). The affected hips had been radiographically normal or subtly osteopenic and had shown intense radionuclide uptake in the femoral head at scintigraphy, with lesser abnormality in the neck and intertrochanteric region. Follow-up MR examinations of five of the six femoral heads showed the diffuse abnormalities to have been transient. Although diffuse MR abnormalities in the proximal femur are not specific, they may indicate the presence of osteonecrosis of the femoral head. 相似文献
79.
Segal I; Sharer NM; Kay PM; Gutteridge JM; Braganza JM 《QJM : monthly journal of the Association of Physicians》1996,89(1):45-53
Vitamin C can be used to overcome oxidative stress and ease pain in chronic
pancreatitis. But its use is deprecated in conditions of tissue iron
overload, because its bioactive form, ascorbate, can accelerate
free-radical reactions that are driven by transition metals. We measured
iron, ascorbate and copper in Sowetan Blacks (RSA) with chronic
pancreatitis, obtaining serum/plasma from 14 consecutive patients and 15
controls. Compared with data from corresponding groups in Manchester,
African samples had less ascorbate (p < 0.0001), but more caeruloplasmin
(p < 0.0001). African and British controls had comparable iron and
iron-binding capacity. Plasma from African patients had less ascorbate than
that from African controls (p < 0.005) and in six samples, ferritin
exceeded 300 micrograms/l (677 pmol/l). Low- molecular-mass iron or copper,
capable of participating in free radical reactions, was not detected.
British patients, had similar caeruloplasmin levels to African patients but
higher ascorbate levels. There is no evidence of iron overload in our
African samples. Outwardly healthy controls from Soweto have elevated
levels of caeruloplasmin, possibly to compensate for dietary deficiency of
ascorbate. Persistent oxidative stress is a unifying feature of chronic
pancreatitis, but its degree is higher in African than British patients.
Supplements of vitamin C should be safe in Blacks of southern Africa.
相似文献
80.
自体造血干细胞的体外净化 总被引:1,自引:0,他引:1
目的:综合分析自体造血干细胞体外净化的方法。资料来源:应用计算机检索Medline 1991-01/2003-12有关自体造血干细胞体外净化方法的文章,检索词“purging,HSCT”,并限定文章语言种类为English。同时计算机检索CNKI数据库1991-01/2003-12有关自体造血干细胞体外净化方法的文章,检索词“体外净化,PUVA”,并限定文章语言种类为中文。资料选择:对相关资料进行整理,选取同一领域、不同方面的文献,以近期发表或权威杂志的文章优先。资料提炼:共检索到42篇有关自体造血干细胞体外净化方法的文献,其中24篇文章符合要求。排除18篇,其中15篇系重复同一研究,3篇为Meta分析。资料综合:自体造血干细胞的体外净化方法很多,如物理方法、生物学方法、药物方法、免疫净化、基因净化等。每种净化方法都有其各自的优势和不足,如淋巴系统疾病可以采用免疫净化;慢性粒细胞白血病患者可考虑反义技术;大多数患者则均可以考虑药物净化的方法。结论:针对不同的疾病,可以选择不同的净化方法,还可以将几种净化方法联合起来,其效果和方法的改进也在不断的研究探索中。 相似文献