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排序方式: 共有704条查询结果,搜索用时 171 毫秒
631.
Fumihiro Mitsunobu Takashi Mifune Kozo Ashida Yasuhiro Hosaki Hirofumi Tsugeno Makoto Okamoto Seishi Harada Yoshiro Tanizaki 《The Journal of asthma》2001,38(5):413-422
To investigate the low-attenuation areas of the lungs (LAA) in asthma, we compared the mean lung density (MLD) and the LAA in 22 asthmatics (12 ex-smokers and 10 nonsmokers) and 13 patients with chronic obstructive pulmonary disease (COPD) by high-resolution computed tomography. The MLD and the relative area of the lung with attenuation values lower than -950 Hounsfield Units at full inspiration (inspiratory RA950) were significantly different in nonsmoking asthmatics compared to patients with COPD and asthmatics with a smoking history. The MLD and the RA950 correlated significantly with the FEV1 in all groups and with the DLCO in patients with COPD and asthmatics with a smoking history but not in nonsmoking asthmatics. We concluded that the LAA in asthmatics with a smoking history indicates the presence of emphysema, but in nonsmoking asthmatics it reflects hyperinflation and nonemphysematous expiratory airflow limitation rather than emphysematous lesions. 相似文献
632.
Adrenal hormones before and after venography during adrenal venous sampling: a self-controlled study
Yuya Koike Seishi Matsui Masao Omura Kohzoh Makita Alfonso W. D. Obara Nobukazu Moriya Tetsuo Nishikawa 《Japanese journal of radiology》2017,35(3):126-130
Objective
A stress reaction involving increased adrenal hormone release occurs when starting adrenal venous sampling (AVS). The purpose of the present study was to investigate the effect of single shot venography on adrenal hormone production during AVS.Subjects and methods
This was a prospective self-controlled study. We enrolled 54 consecutive patients (21 men, 33 women; mean age 52 ± 11 years) with primary aldosteronism who underwent AVS from May 2014 to February 2015. Under non-stimulated conditions, blood samples were obtained from a common trunk of the left adrenal vein before and after single shot venography. The initial plasma aldosterone and cortisol concentration (PAC and PCC) were compared with those measured after venography for each patient.Results
PAC and PCC were slightly but significantly decreased between before and after venography (after log transformation 2.12 ± 0.73 vs 2.07 ± 0.72, P = 0.00066, 1.89 ± 0.52 vs 1.83 ± 0.53, P = 0.00031, respectively).Conclusions
During non-stimulated left AVS, adrenal hormone secretion was slightly but significantly decreased after venography, similar to the normal time-related stress reaction. Venography did not increase the adrenal hormone secretion.633.
Yasuo Miyoshi Masafumi Kurosumi Junichi Kurebayashi Nariaki Matsuura Masato Takahashi Eriko Tokunaga Chiyomi Egawa Norikazu Masuda Seishi Kono Koji Morimoto Seung Jin Kim Masatsugu Okishiro Tetsu Yanagisawa Satsuki Ueda Tetsuya Taguchi Yasuhiro Tamaki Shinzaburo Noguchi 《Breast cancer (Tokyo, Japan)》2010,17(2):103-109
Predictive factors for anthracycline-based chemotherapy have yet to be incorporated into daily practice. Meta-analyses of studies using anthracycline-based treatment regimens have shown an improved prognosis for human epidermal growth factor receptor type 2 (HER2)-positive tumors, but not for HER2-negative tumors compared with results of non-anthracycline regimens. Currently it is believed that the positive association between HER2 status and anthracycline sensitivity is indirect, that is, their association may be mediated through topoisomerase II alpha (TOP2A), a target molecule of anthracyclines, since TOP2A is near HER-2 and co-amplification of the TOP2A gene frequently occurs in HER2-amplified tumors. This strongly suggests that TOP2A gene amplification is a predictive factor for anthracyline-based regimens. The Collaborative Study Group of Scientific Research of the Japanese Breast Cancer Society has demonstrated that TOP2A-positive and BRCA1-negative subsets evaluated by immunohistochemical staining show a significantly higher pathological complete response when treated with preoperative epirubicin-containing regimens. Combining these findings with the observation that triple-negative tumors and basal-like tumors respond to anthracycline treatment suggests that not only HER2-positive tumors but also a distinct subset of HER2-negative tumors may be sensitive to anthracycline-based regimens. 相似文献
634.
635.
Maeba H Takehana K Nakamura S Yoshida S Ueyama T Hatada K Iwasaka T 《Annals of nuclear medicine》2008,22(4):309-316
OBJECTIVE: Although the accurate detection of ischemic etiology is important in the management of patients with severe left ventricular (LV) dysfunction, it is difficult to determine using a non-invasive strategy. The present study investigates whether perfusion and regional functional abnormalities identified by quantitative electrocardiographic gated single-photon emission computed tomography (QGS) at rest can detect ischemic LV dysfunction in patients with severe LV dysfunction. METHODS: Rest QGS with (99m)Tc-tetrofosmin was performed on 54 consecutive patients with LV ejection fraction of =40%. Ischemic LV dysfunction (n = 32) was defined according to the established standard. Regional perfusion and wall motion were calculated using a 14-segment model (six mid-ventricular and eight apical segments) and compared with a normal control group. RESULTS: The numbers of reduced [mean -1 standard deviation (SD) of normal individuals] and severely reduced (mean -2 SD) wall motion segments were similar between patients with ischemic and non-ischemic LV dysfunction (13.5 +/- 1.1 vs. 13.6 +/- 0.9 and 10.6 +/- 2.0 vs. 9.9 +/- 3.0 segments, respectively). The number of hypoperfused (mean -1 SD) segments was significantly greater in patients with ischemic LV dysfunction than in those with non-ischemic LV dysfunction (9.3 +/- 3.8 vs. 2.0 +/- 2.8 segments, P < 0.0001). The analysis of the receiver operating characteristics showed that a cut-off value of 4 hypoperfused segments among 14 segments provided the best separation between ischemic and non-ischemic LV dysfunction (sensitivity = 88% and specificity = 91%). Furthermore, patients with non-ischemic LV dysfunction had no severely hypoperfused (mean -2 SD) segments in any of the segments, whereas patients with ischemic LV dysfunction had 4.4 +/- 0.2 segments. CONCLUSIONS: The QGS strategy at rest can accurately differentiate patients with ischemic LV dysfunction from those with severe LV dysfunction by simultaneous regional evaluation of wall motion and myocardial perfusion. 相似文献
636.
Deguchi M Kagita M Asari S Iwatani Y Tuchida T Iinuma K Sanborn M 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2005,79(2):138-142
Mutants of hepatitis B virus surface antigen (HBsAg) are known as a cause of false-negative results in diagnostic tests for HBsAg; particularly when a diagnostic kit utilizes monoclonal antibodies to detect HBsAg. We compared seven HBsAg kits with regard to sensitivity for HBsAg subtypes (ad, ay) and their ability to detect nine different HBsAg mutants. Among them, the sensitivities of five kits were high and comparable to each other (0.2 - 0.3ng/ml). However, two kits were of lower sensitivity (0.8-1.3ng/ml, and 2.4-2.5ng/ml, respectively). Two kits, produced by the same company, reacted with all of the nine HBsAg mutants, but five kits showed false-negative results with one or more of the HBsAg mutants. These data indicate that there are differences in the detection sensitivities for HBsAg and abilities to detect HBsAg mutants among commercially available HBsAg kits, which may explain false-negative clinical results. 相似文献
637.
Tanimoto A Wakabayashi G Shinmoto H Nakatsuka S Okuda S Kuribayashi S 《Journal of gastroenterology》2005,40(4):371-380
Background We aimed to evaluate the efficacy of a breath-hold superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging protocol for the detection of focal hepatic lesions, in comparison with a non-breath-hold SPIO-enhanced imaging protocol and computed tomography during arterioportography (CTAP) plus CT during hepatic arteriography (CTHA).Methods Findings of SPIO-enhanced MR imaging and CTAP/CTHA for 24 hepatic metastases in 17 patients and 29 HCCs in 21 patients were analyzed. All patients underwent breath-hold SPIO-enhanced MR imaging (1.5 tesla), breath-hold plus non-breath-hold SPIO-enhanced MR imaging, and CTAP plus CTHA prior to partial hepatectomy or laparoscopic ablation therapy. Histopathology for lesion characterization and intraoperative ultrasound for lesion detection were available for all patient. Breath-hold SPIO-enhanced MR imaging consisted of T2-weighted single-short fast spin echo (FSE), T2-weighted (T2W) FSE, T2*-weighted gradient echo (GRE), and T1-weighted GRE. For the non-breath-hold imaging protocol, respiratory-triggered, fat-suppressed T2W-FSE was added to the breath-hold MR imaging protocol. Double phase CTAP plus CTHA was performed on an angio-CT system. To compare the three imaging protocols, three radiologists performed blind film reading, and all data, on a hepatic segment-to-segment basis, were entered for alternative free-response receiver-operating characteristic (AFROC) analysis.Results ROC analysis showed that there was no significant difference in the area under the AFROC curve (A1) value for metastases and HCCs among the three protocols; the breath-hold SPIO-enhanced MR imaging protocol, non-breath-hold MR imaging protocol, and CTAP plus CTHA. The breath-hold SPIO-enhanced MR imaging protocol showed a sensitivity, specificity, and accuracy equivalent to the non-breath-hold MR imaging protocol and CTAP plus CTHA.Conclusions As a preoperative test, SPIO-enhanced MR imaging could have the potential to replace CTAP plus CTHA in a certain clinical setting. 相似文献
638.
Kurihara H Nakamura S Takehana K Fukui M Sawanishi T Maeba H Ueyama T Hatada K Sugiura T Iwasaka T 《Nuclear medicine communications》2005,26(6):505-511
OBJECTIVE: The clinical usefulness of characterizing reperfused myocardium by perfusion/thickening assessment using electrocardiographic gated single photon emission computed tomography (SPECT) has not been investigated. We evaluated whether single-injection gated SPECT with 99mTc tetrofosmin early after primary percutaneous coronary intervention (PCI) can predict left ventricular (LV) functional recovery. METHODS: Gated SPECT was performed 3 days after primary PCI in 45 patients with acute myocardial infarction and revascularized segments were classified into perfusion/thickening mismatched segments, matched normal and matched abnormal segments. Gated SPECT was repeated 3 months later to evaluate the changes in LV ejection fraction (deltaLVEF). RESULTS: Among 332 revascularized segments, there were 83 mismatched segments, 163 matched abnormal segments and 86 matched normal segments. In all the patients, LVEF increased significantly from 3 days to 3 months after primary PCI (52+/-13 to 57+/-14%, P<0.0001). Patients were divided into two groups according to deltaLVEF: 24 patients with LV functional recovery (deltaLVEF > or = 5%) and 21 patients without LV functional recovery. The number of mismatched segments in patients with LV functional recovery was significantly greater than that in patients without (2.7+/-1.7 vs. 0.8+/-1.4, P<0.0003) despite no differences in the number of matched abnormal and matched normal segments. There was a significant correlation between deltaLVEF and the number of mismatched segments (r=0.56, P<0.0001) and LVEF at 3 months after primary PCI was related to the number of matched abnormal segments (r=-0.78, P<0.0001). CONCLUSION: Single-injection gated SPECT early after primary PCI can predict LV functional recovery. 相似文献
639.
Fujita D Terada S Ishizu H Yokota O Nakashima H Ishihara T Kuroda S 《Acta neuropathologica》2003,105(3):259-264
Fahr-type calcification is a relatively common finding in the elderly, and in younger patients with Alzheimer's disease, calcification in the basal ganglia is not uncommon. However, as far as we know, an immunohistochemical study of intracranial calcification in neurodegenerative diseases has not been performed. In this study, we examined intracranial calcification of the basal ganglia and cerebellum with antibodies against noncollagenous bone matrix proteins. Nineteen brains were employed. The diagnoses were diffuse neurofibrillary tangles with calcification in five, Alzheimer's disease in five, Pick's disease in one, progressive supranuclear palsy in one, Parkinson's disease in one, and six controls. By conventional histology, three patterns of calcium (Ca) deposition were recognized: diffuse deposition within the tunica media of small and medium-sized vessels (type 1 deposition), free spherical or lobulated concretions (type 2 deposition) in the parenchyma, and rows of small calcospherites lying along capillaries (type 3 deposition). Type 3 deposition is relatively rare, and may be a hallmark of severe intracranial calcification. Immunohistochemistry demonstrated that osteopontin was present diffusely in all Ca deposition types. Osteocalcin was present chiefly in the peripheral region of type 2 and 3 depositions, as well as in only the rims of type 1 deposition. Bone sialoprotein and osteonectin were found only in the core portions of type 2 and 3 depositions. In brief, type 1 deposition shows a different staining pattern from type 2 and 3. Different Ca deposition patterns of noncollagenous bone matrix proteins may suggest their separate roles in the pathogenesis of intracranial calcification. 相似文献
640.
Murakami T Kim T Kawata S Kanematsu M Federle MP Hori M Okada A Kumano S Sugihara E Tomoda K Nakamura H 《Investigative radiology》2003,38(8):497-503
PURPOSE: We evaluated the optimal timing of arterial phase imaging for detection of hypervascular hepatocellular carcinoma by using triple arterial phase imaging with multidetector-row helical computed tomography. MATERIALS AND METHODS: Forty-nine patients with 90 hypervascular hepatocellular carcinomas (3 to 50 mm in diameter; mean, 18.7 mm) underwent triple arterial phase imaging of the whole liver using a multidetector-row helical computed tomography. At 20 seconds, 30 seconds, and 40 seconds after intravenous administration of 100 mL of 300 mgI/mL of nonionic contrast medium at a rate of 4 mL/s, early, middle, and late arterial phase images were obtained serially during a single breath-hold with an interscan delay of 5 seconds. Detector-row configurations of 4 mm x 4, scan pitch of 5.5, and scan time of 5 seconds for each phase were used. Forty prospective reconstruction images of 5-mm thickness for each phase were obtained. The images from each phase were interpreted separately for detection of hypervascular hepatocellular carcinoma by 3 observers independently who were unaware of tumor burden in the liver. Sensitivity, positive predictive value, and area under the receiver operating characteristic curve values for each arterial phase were calculated and compared statistically. RESULTS: The mean sensitivity and positive predictive values for hypervascular hepatocellular carcinoma diagnosis of blind readers were 37% and 87% for the early arterial phase, 73% and 85% for the middle arterial phase, and 49% and 81% for the late arterial phase, respectively. The middle arterial phase imaging showed significantly superior sensitivity compared with the early and late arterial phase for detecting hepatocellular carcinoma (P < 0.05). Mean area under the receiver operating characteristic curve value of the middle arterial phase imaging (0.84) was significantly higher that that of the early (0.56) or late arterial phase (0.62; P < 0.05). CONCLUSION: If a single arterial phase is used for diagnosis of hypervascular hepatocellular carcinoma, the middle phase (delay time of 30 seconds) is optimal. 相似文献