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71.
The mechanical activity of the human quadriceps muscle during maximal incremental cycle ergometry was investigated by mechanomyography (MMG). MMG and surface electromyography (EMG) recordings of vastus lateralis muscle activity were obtained from nine males. Cycle ergometry was performed at 60?rev/min and work load was incremented step wise by 20?W (3.2?Nm) every minute until volitional fatigue. The mean amplitudes of MMG (mMMG) and EMG (mEMG) during the contraction phase were calculated from the last six contractions in each load. The duration, load and work rate of exercise at exhaustion were 13.3 (1.6)?min, 44.1 (5.5)?Nm, 276.7 (34.7)?W, respectively. A linear relationship between mMMG and load was evident in each subject (r?=?0.868–0.995), while mEMG seemed to dissociate as the load became greater. In the grouped mean data, mMMG was linearly related to load whether aligned to the absolute (r?=?0.995) or maximal (r?=?0.995) load. Involvement of the noise component was further investigated by studying passive cycling by four subjects. Pedals were rotated passively for the first half of each stage (PAS) and the subject then pushed the pedals for the second half (ACT). In the lighter load region, the mMMG of ACT was as small as that of PAS. However, the change in the mMMG of PAS was very small compared with that of ACT. In conclusion, this study demonstrates a linear relationship between the mMMG of the quadriceps muscle and work load during maximal incremental cycle ergometry. The effect of movement noise was thought to be small and stable.  相似文献   
72.
We have examined the distribution of antigens detected by MB1, MB2 and MB3 on non-hematopoietic normal human tissues and various types of benign and malignant tumors. MB1 and MB2 reacted with various organs, such as the epithelium of various glands, smooth muscle cells, vascular endothelial cells, and peripheral nerve tissue. The distributions of these two antibodies were essentially identical. Reactivity with MB3 was confined to the ductal eDithelium of salivary glands, the pancreas, and sweat glands, and the cortex of the adrenal gland. lmmunoblotting analysis demonstrated that MB1 and MB2 reacted with a few bands of an extract of myometrial cytoskeletal fraction and salivary gland cytosol fraction, whereas MB3 failed to show any bands on these materials. The reactivities of MB1 and MB2 with various neoplasms were similar to those in normal organs, with slight variations of staining pattern and preponderance in well differentiated tumors. Exceptionally, carcinoid tumor and small round cell tumors, such as small cell carcinoma or neuroblastoma, were not reactive with MB1 and MB2. MB3 reacted with several cases of well differentiated benign and malignant epithelial tumors in various organs, and exceptional cases of malignant schwannoma and glioma. These results indicate that the antigens detected by MB1 and MB2 are distributed broadly on non-hematopoietic normal organs, whereas those detected by MB3 are confined to exceptional cases of epithelial and non-epithelial tumors. Thus, although the use of MB1, MB2 and MB3 is of little value for differential diagnosis of various tumors, these three antibodies may be useful for determining of the origin of some tumor types. Acta Pathol Jpn 42: 339–346, 1992.  相似文献   
73.
Serum antibody responses of mice to repeatedly inhaled protein antigens such as bovine serum albumin and ovalbumin, plus or minus bacterial lipopolysaccharide (LPS) in the form of an aerosol were studied. Results showed that the levels of responses to inhaled protein antigens varied, depending on the mouse strain-antigen combination and that LPS inhaled simultaneously with the antigens definitely augmented the responses which were not otherwise very high. LPS extracted from Klebsiella O3 (LPS-K) but not LPS from Escherichia coli O55 (LPS-E), which was inhaled at the time of initial inhalation of antigen, significantly intensified the priming for the secondary antibody response to the antigen subsequently inhaled. Both LPS-K and LPS-E, however, definitely acted to augment the response when they were inhaled repeatedly together with the antigen. Oral administration of antigen or antigen plus LPS-K did not induce any detectable antibody response in our experiment, ruling out the possibility that the antigen and LPS stimulated the immune system via alimentary canal rather than via lung. Tissue distribution of the radioactivity soon after inhalation of 131I-labeled antigen and decay speed of the radioactivity were not significantly changed by LPS-K inhaled simultaneously. This suggested that the augmentation of responses was not mediated by the action of LPS to modulate the air-blood barrier against the entry of antigen via lung. All the results prove for the first time that inhaled LPS displays a definite adjuvant action on antibody responses to inhaled antigens.  相似文献   
74.
75.
We have previously reported that gamma delta T cells play important roles in protection during the early stage of infection with Listeria monocytogenes in mice. To generalize the protective roles of gamma delta T cells in listerial infection to different species, we examined the appearance of gamma delta T cells during infection with L. monocytogenes in Fisher F344 rats. The numbers of bacteria in the peritoneal cavity and liver increased to a maximum level on day 3 and then decreased to an undetectable level by day 10 after an intraperitoneal infection with a sublethal dose (1 x 10(8)) of viable L. monocytogenes in rats. CD3+ alpha beta- T cells in the peritoneal cavity and liver began to increase on day 3, reached a maximum level on day 6, and thereafter decreased gradually by day 10 after infection. Northern blot analysis confirmed that the CD3+ alpha beta- T cells expressed TCR delta and gamma gene messages. In vivo treatment with anti-TCR alpha beta mAb, which suppressed most of the alpha beta T cells in the periphery and impaired resistance during the late stage of listerial infection, did not affect the host defense by day 6 after infection. A significantly increased number of gamma delta T cells was detected in the peritoneal cavity of the TCR alpha beta-suppressed rats on day 6 after infection. These results suggest that the early appearing gamma delta T cells may contribute to the host defense at a relatively early stage during listeriosis in rats.  相似文献   
76.
Sato H  Hasegawa T  Abe Y  Sakai H  Hirohashi S 《Human pathology》1999,30(11):1344-1349
The cadherin-mediated cell-cell adhesion system is now known to play a critical role in both the morphogenesis of cancer cells and suppression of their invasion. However, the pattern of expression of E-cadherin, the major cadherin of epithelial cells in bone and soft tissue sarcomas, remains unclear. This prompted us to study E-cadherin expression in a variety of bone and soft tissue sarcomas. Using the monoclonal antibody HECD-1, raised against the extracellular domain of E-cadherin, we observed immunoreactivity in 1 pleomorphic rhabdomyosarcoma, 2 of 5 diffuse mesotheliomas, 4 of 5 clear cell sarcomas, 1 of 5 epithelioid sarcomas, and 10 synovial sarcomas. Other types of bone and soft tissue sarcoma (4 osteosarcomas, 4 chondrosarcomas, 3 primitive neuroectodermal tumors, 1 fibrosarcoma, 4 malignant fibrous histiocytomas, 5 liposarcomas, 4 leiomyosarcomas, 6 alveolar and 5 embryonal rhabdomyosarcomas, 4 angiosarcomas, 4 malignant peripheral nerve sheath tumors, 2 extraskeletal myxoid chondrosarcomas, 2 extraskeletal osteosarcomas, and 3 alveolar soft part sarcomas) were completely negative for E-cadherin. Our findings indicate that E-cadherin is expressed in certain kinds of soft tissue sarcomas, especially those with epithelioid features, suggesting that E-cadherin plays a role in the constitution of their architecture.  相似文献   
77.
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva.  相似文献   
78.
79.
A case is reported of atypical glomus tumor occurring in the posterior inferior mediastinum of a 26-year-old woman complaining of severe back pain. The tumor was composed of atypical small, round tumor cells with scattered mitotic figures. In addition to sheet-like, diffuse proliferation of the tumor cells, some areas of the tumor contained small “glo-moid” cells arranged in organoid and hemangiopericytoma-like patterns. Immunohistochemically, many tumor cells were positive for muscle-type actins and a few cells were focally positive for desmin. Ultrastructural studies revealed smooth muscle features of tumor cells, that is, pinocytotic vesicles, external laminas, dense plaques, and occasional thin filaments with dense bodies. The patient remained well for 5 years and 4 months after the operation without additional radiation and chemotherapy. The tumor was diagnosed as an atypical, or low-grade malignant, glomus tumor morphologically. It seems important to recognize the presence of this type of tumor in sites other than extremities and to differentiate it from other malignant small, round cell tumors.  相似文献   
80.
In order to investigate the mechanism of urinary tract stone formation, we analyzed protein components in urine and the stone. Urinary proteins of healthy subjects and urolithic patients as well as protein components urinary tract stone of the urolithic patients were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Electrophoretic patterns of urinary proteins of the patients differed from those of healthy subjects after separating protein patterns into those larger than 66kDa or smaller than 30kDa. Protein constituents of urinary tract stone were mainly separated into 18 bands ranging from 26.8 to 143 kDa. Major bands among these 18 bands differed among stones from different patients. On western blotting, the developed intensities of Tamm-Horsfall protein (THP) were fainter than those of healthy subjects. Whereas intensities of albumin (ALB) were stronger than those of healthy subjects. Moreover, blotting patterns of THP of the patients on non-reducing SDS-PAGE were obviously broad. Thus, we suggest that analysis of fractionated urinary proteins or protein components of urinary tract stone may provide a tool for monitoring the prognosis or relapse in the patients.  相似文献   
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