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91.
Z Radák A Nakamura H Nakamoto K Asano H Ohno S Goto 《Canadian Metallurgical Quarterly》1998,435(3):439-441
Compartment syndrome is caused by an increase in intracompartmental pressure above the capillary level, preventing capillary flow. The acute onset of symptoms occurs after events such as fracture, soft tissue trauma, and revascularization and usually necessitates prompt fasciotomy to avoid loss of function or even necrosis of the enclosed muscle. Compartment syndromes in athletes are of a recurrent nature and are usually referred to as chronic. Nonoperative treatment is often successful. Although compartment syndromes can occur in several anatomic regions, the most commonly seen in athletes involve the leg. Chronic compartment syndromes of the upper extremity are rare, and only a few cases have been reported in the literature. The intracompartmental pressures causing chronic symptoms in these cases ranged between 22 mm Hg at rest and 40 mm Hg after 30 minutes of exercise. Under maximal contraction, a pressure of 58 mm Hg has been recorded. The object of this paper is to report a case of a tennis player where much higher flexor-pronator muscle intracompartmental pressures than those noted above were recorded. We compared the intracompartmental pressure data of this patient with intracompartmental pressures measured in six symptom-free volunteers. 相似文献
92.
Experiments were carried out to investigate the flow pattern, average void fraction, and pressure drop of an upward air‐water two‐phase flow in vertical tubes of 25‐mm inside diameter with wire coils of varying wire diameter, pitch, and number of coils in cross section. Five kinds of flow patterns—bubble, slug, churn, semiannular, and annular flow—were defined based on the observation of flow behavior in the experiments. At higher water flowrates, the bubble‐to‐slug transition occurred at lower air flowrates in tubes with wire coils than in smooth tubes. The average void fraction was found by using the drift flux model. Further, the experimental results of the friction pressure drop were compared with the Lockhart‐Martinelli correlation. As a result, a correlation with the constant C in Chisholm's equation was obtained as a function of the wire coil pitch‐to‐diameter ratio. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(8): 639–651, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10066 相似文献
93.
N Asano A Kato K Matsui AA Watson RJ Nash RJ Molyneux L Hackett J Topping B Winchester 《Canadian Metallurgical Quarterly》1997,7(8):1085-1088
The polyhydroxylated nortropane alkaloids called calystegines occur in many plants of the Convolvulaceae, Solanaceae, and Moraceae families. Certain of these alkaloids exhibit potent inhibitory activities against glycosidases and the recently demonstrated occurrence of calystegines in the leaves, skins, and sprouts of potatoes (Solanum tuberosum), and in the leaves of the eggplant (S. melongena), has raised concerns regarding the safety of these vegetables in the human diet. We have surveyed the occurrence of calystegines in edible fruits and vegetables of the families Convolvulaceae, Solanaceae, and Moraceae by GC-MS. Calystegines A3, B1, B2, and C1 were detected in all the edible fruits and vegetables tested; sweet and chili peppers, potatoes, eggplants, tomatoes, Physalis fruits, sweet potatoes, and mulberries. Calystegines B1 and C1 were potent competitive inhibitors of the bovine, human, and rat beta-glucosidase activities, with Ki values of 150, 10, and 1.9 microM, respectively for B1 and 15, 1.5, and 1 microM, respectively, for C1. Calystegine B2 was a strong competitive inhibitor of the alpha-galactosidase activity in all the livers. Human beta-xylosidase was inhibited by all four nortropanes, with calystegine C1 having a Ki of 0.13 microM. Calystegines A3 and B2 selectively inhibited the rat liver beta-glucosidase activity. The potent inhibition of mammalian beta-glucosidase and alpha-galactosidase activities in vitro raises the possibility of toxicity in humans consuming large amounts of plants that contain these compounds. 相似文献
94.
95.
H Yasuda T Mine H Shibata Y Eto Y Hasegawa T Takeuchi S Asano I Kojima 《Canadian Metallurgical Quarterly》1993,92(3):1491-1496
The present study was conducted to examine the effect of activin A on growth of rat hepatocytes. EGF induced a 10-fold increase in DNA synthesis as assessed by [3H]thymidine incorporation in cultured hepatocytes. When activin A was added together with EGF, DNA synthesis induced by EGF was markedly inhibited. Inhibition was detected at a concentration of 10(-10) M, and 5 x 10(-9) M activin A almost completely blocked EGF-mediated DNA synthesis. Similarly, activin A completely blocked DNA synthesis induced by hepatocyte growth factor/scatter factor. Activin A was capable of inhibiting EGF-mediated DNA synthesis, even when added 36 h after the addition of EGF. With the same time interval, TGF-beta also blocked EGF-induced DNA synthesis. Although both activin A and TGF-beta inhibited growth of hepatocytes in a similar manner, either activin A or TGF-beta did not compete with each other in their binding when assessed by competitive binding using an iodinated ligand. When hepatocytes were incubated with EGF, release of bioactivity of activin A into culture medium was detected after 48 h or later. Activity of activin A was released from parenchymal cells but not from nonparenchymal cells. mRNA for beta A subunit of activin was detected only slightly in unstimulated hepatocytes, but markedly increased at 48 h after the addition of EGF. To determine whether endogenously produced activin A affects DNA synthesis, we examined the effect of follistatin, an activin-binding protein that blocks the action of activin A. An addition of follistatin significantly enhanced EGF-induced DNA synthesis. Finally, in partial hepatectomized rat, expression of mRNA for beta A subunit in liver was markedly increased 24 h after the partial hepatectomy. These results indicate that activin A inhibits initiation of DNA synthesis in hepatocytes by acting on its own receptor and that activin A acts as an autocrine inhibitor of DNA synthesis in rat hepatocytes. 相似文献
96.
97.
This paper describes the priority of propagation among three parallel cracks. The treated object is an infinite elastic body with three parallel cracks subjected to uniform tension or antiplane shear at infinity. The results make it clear that the longest crack does not always have the biggest value relating to fracture, e.g. the biggest tangential stress at crack tip or the biggest stress intensity factor, because of the interaction among the cracks. 相似文献
98.
Determination of the cell proliferation activity of neoplasm is useful in making a prognosis. Immunohistochemical detection using MIB-1 monoclonal antibody has recently allowed us to assess tumor cell proliferation easily, because it can be performed on paraffin-embedded specimens and the results have been demonstrated to be positively correlated with the results of PCNA staining. In this study, surgical specimens of 63 pituitary adenomas were examined by immunohistochemical staining with MIB-1 monoclonal antibody. Twenty-nine cases were non-functioning pituitary adenomas, 20 were prolactin (PRL)-producing pituitary adenomas, and 14 were growth hormone (GH)-producing pituitary adenomas. The MIB-1 positive rates of the pituitary adenomas ranged from 0% to 6.46%. In the non-functioning pituitary adenomas, the MIB-1 positive rates ranged from 0% to 4.55% (mean : 0.76%), in the PRL-producing pituitary adenomas the MIB-1 positive rates ranged 0% to 6.46% (mean : 0.91%), and in the GH-producing pituitary adenomas the MIB-1 positive rates ranged 0% to 1.28% (mean: 0.58%). There were no significant differences between these values according to the results of the Wilcoxon signed-rank test. Although the size of the non-functioning pituitary adenomas was not correlated with their MIB-1 positive rate, tumor size was closely correlated with the interval between the onset of the initial symptoms and the date of surgery. In the PRL-producing pituitary adenomas, the MIB-1 positive rate was not correlated with serum PRL levels as an index of secretory activity, but was correlated with the PRL staining positive rate. Preoperative bromocriptine therapy proved effective in reducing tumor size and serum PRL levels, but had no effect on the MIB-1 positive rate. In the GH-producing pituitary adenomas, the MIB-1 positive rate was not correlated with serum GH levels as an index of secretory activity, but was closely correlated with the GH staining positive rate. All three groups included both invasive and noninvasive tumor types, but there were no close statistical correlations between the three tumor types. 相似文献
99.
100.
A 64-year-old male consulted our hospital with a 6-day history of malaise, body temperature to 38 degrees C, anorexia, and light headedness. The chest radiograph showed consolidation in the left lower lung area. Chest CT and ultrasonography revealed left pleural fluid. The pleural fluid was exudative (yellowish in color, protein 3.0 g/dl, Rivalta reaction positive, adenosine deaminase 19.4 U/L), and had a total cell count of 4.7 x 10(6)/ml with 45% lymphocytes, 40% histiocytes, and 15% polymorphonuclear leukocytes. He had kept a budgerigar, but we could not isolate Chlamydia from the pleural fluid or the pet bird. Transbronchial lung biopsy from left S10 revealed an increase of mononuclear leukocytes within the interstitial spaces, and the alveolar spaces contained polymorphonuclear leukocytes, fibrin, and organized alveolar exudate. Bronchoalveolar lavage cellular constituents were 50% lymphocytes, 27% neutrophils, and 23% macrophages. Serologic studies demonstrated C. trachomatis specific IgM antibody titers at 1:20 in a serum sample and at 1:10 in pleural fluid. We report a case of community-acquired pneumonia caused by C. trachomatis diagnosed by serologic studies. 相似文献