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51.
As demonstrated by others, diisopropyl fluorophosphate (DFP) markedly inhibits the O2- generation from guinea-pig polymorphonuclear leukocytes (PMN) stimulated by an antibody complex with ovalbumin (Ag-Ab complex), and also the intracellular uptake of antibody-sensitized erythrocytes by the cells. However, when PMN were treated with DFP and washed to remove the inhibitor, they again became able to exhibit the O2- -generating and phagocytic activities. The [3H]DFP-labeling of intact PMN followed by solubilization with Triton N101, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed the existence of several [3H]DFP-labeled proteins with different mol. wts, which disappeared on pretreatment of cells with cold DFP. However, stimulation of DFP-pretreated PMN with Ag-Ab complex in the presence of [3H]DFP resulted in the appearance of a [3H]DFP-labeled, membrane-bound protein with a mol. wt of 40,000. This protein was isolated by affinity chromatography of the solubilized PMN and phagosomes on anti-Ig antibody-Sepharose 4B. Although the enzymatic properties of the protein are not clear, the results so far obtained suggest that it is a putative, stimulus-activated serine protease participating in the triggering events leading to the activation of NADPH oxidase responsible for the respiratory burst and the formation of phagosomes. 相似文献
52.
Influenza virus overcomes apoptosis by rapid multiplication 总被引:1,自引:0,他引:1
Kurokawa M Koyama AH Yasuoka S Adachi A 《International journal of molecular medicine》1999,3(5):527-530
The kinetics of apoptotic fragmentation of the chromosomal DNA was determined in the influenza virus-infected MDCK, HeLa and KB cells, respectively. Comparison of these kinetics with the kinetics of virus multiplication revealed that the multiplication of influenza virus was observed only when apoptosis was induced after the production of progeny virus in the infected cells. The extent of apoptotic response was reversely correlated with the permissiveness of the cells. 相似文献
53.
54.
Muramatsu Y; Takayasu K; Moriyama N; Shima Y; Goto H; Ushio K; Yamada T; Hasegawa H; Koyama Y; Hirohashi S 《Radiology》1986,160(1):49-52
To aid in the distinction between colorectal cancer metastasis to the liver and hepatocellular carcinoma, findings on computed tomographic (CT) scans taken more than 5 minutes after contrast material administration ("late-enhanced CT scans") and pathologic findings were compared. Late-enhanced CT scans of metastatic adenocarcinoma showed a peripheral low-density area (PLDA) that corresponded to viable tumor and a central high-density area that represented fibrous connective tissue. This phenomenon was recognized in 15 of 20 (75%) patients with metastatic adenocarcinoma and in one of 50 (2%) patients with hepatocellular carcinoma. Late-enhanced CT scans may be useful in distinguishing between metastatic nonmucinous colorectal cancer and hepatocellular carcinoma. 相似文献
55.
Kunihiko Shiraki Mitsuyasu Moriwaki Muneaki Matsumoto Takeya Khono Tokuhiko Miki 《International ophthalmology》1997,21(1):43-50
Purpose. Hypofluorescent spots were seen inindocyanine green (ICG) angiography of peau dorangefundus in eyes with angioid streaks. Origin of the hypofluorescentspots were examined with attention to their correlationwith a peau dorange appearance of the central fundususing a computer-assisted image comparison system. Methods. ICG angiography was performed in 5 patientshaving peau dorange appearance of fundus using ascanning laser ophthalmoscope (SLO) and a digitalvideo-fundus camera. The same central fundus areas corresponding to hypofluorescent spots in an ICGangiogram were then digitally identified in afluorescein angiogram and in a red-free picture in all10 eyes of the 5 patients. Monochromatic lightobservation was also performed with a dark fieldobservation using a SLO to see subretinal orintrachoroidal pigment clumping. Results. In no patient, the areas identified withhypofluorescent spots did show relevant changes ina fluorescein angiogram or a red-free picture. SLOexamination revealed not perfusion defect at the sameareas. The dark field observation showed no pigmentclumping at the peripapillary and papillomacularbundle regions where hypofluorescent spots were seen.Conclusions: Hypofluorescent spots seen in ICGangiograms did not show exact consistency with peau dorange changes in their location and shape. Perfusion defects or blocking by pigments were not acause of hypofluorescent spots. The scatteredhypofluorescent spots were considered to be relevantwith irregular affinity of the fundus to ICG dye. 相似文献
56.
Gennady E. Tur M.D. Hitoshi Kotanagi M.D. Dr. Kenji Koyama M.D. 《Diseases of the colon and rectum》1994,37(6):604-605
A modified technique for handsewn anastomosis after abdominoperineal pull-through resection is described. The technique is a continuous locked modification of the Gambee suture. Simplicity, rapidity, reliability, and firmness are the advantages of this technique. 相似文献
57.
Neurons in the temporal cortex changed their preferred direction of motion dependent on shape 总被引:1,自引:0,他引:1
To investigate neuronal mechanisms that integrate different visual modalities such as motion and shape, neuronal activities in the superior temporal polysensory area (STP) were recorded from monkeys that were watching rotating images. In total, 194 neurons were identified as visually responsive. Of these, 73 neurons (38%) showed differential response depending on both shape and direction of motion (MS neurons). Of these 73 neurons, 21 (29%) were identified as reversal type MS neurons (MSr neurons), that is, they responded to an opposite preferred direction when the shape was different. The results confirm that neurons in the STP can be simultaneously activated by different attributes of visual stimuli. The data also suggest that individual STP neurons can process more than one type of visual stimulus. 相似文献
58.
Y Yang K Kinoshita K Koyama K Takahashi T Tai Y Nunoura K Watanabe 《Planta medica》1999,65(6):574-576
A novel experimental model of free radical-induced emesis for screening anti-emetic compounds from natural sources was established. 2,2'-Azobis(2-amidinopropane) dihydrochloride (AAPH) dissolved in liposome induced emesis in young chickens, and the emesis was prevented by antioxidants including N-(2-mercaptopropionyl)-glycine (MPG), alpha-tocopherol, and L-ascorbic acid. Tropiseton, a serotonin receptor antagonist, also prevented emesis induced by AAPH. Known anti-emetic drugs and anti-emetic principles from natural sources also showed significant retching inhibition in the experiment using this system. 相似文献
59.
Copper IUDs and polyethylene IUDs were inserted in Clauberg rabbits. Proliferation of endometrium caused by exogenous progesterone was markedly inhibited in the rabbits with the copper IUD. Maximum proliferation was seen in the contralateral uterine horn of the rabbits with polyethylene IUDs. The concentration of Cu-ion in the endometrium in the horn with Cu-IUD showed a higher level as 19.5 ug/g wet wt. than that in the control horn, 2.5 ug/g wet wt. This effect corresponds to the addition of Cu-ion in a concentration of higher dosage to the endometrium of the control horn. In the case of women with normal menstrual cycles, the increase in a concentration of Cu-ion in the endometrium with Cu-IUD was lower than 10-5M; in the control women the concentration was 1.6 ug/g wet wt. of endometrium. The histological dating of endometrial specimens (E-B date) with Cu-IUD was examined and compared with expected date of the cycle determined by BBT date. Cu-IUD did not induce any significant discrepancy in both dating. The mechanism of increasing contraceptive effect with Cu-ion was considered to be a little different than in rabbits. (Author's Modified) 相似文献
60.
A rare case of cranial fasciitis in a 1-year-old boy arising in the temporoparietal bone has been described. In 1990, Lauer and Endinger first reported cranial fasciitis, which is a benign subcutaneous tumor of the head developing from the deep fascia or the cranial periosteum and showing a pathological finding characterized by proliferation of fibroblasts. They described this tumor as "cranial fasciitis of childhood" in view of a high incident in infants and child. Cranial fasciitis grows rapidly in the scalp without pain, but its mean size is 2.5-3cm. Cranial fasciitis is closely related a clinical course and pathological findings to nodular fasciitis, which is also a benign proliferative fibroblast tumor developing from the subcutaneous muscular layers of the trunk and extremities (especially, the forearms), which was reported by Konwaler in 1955. However, cranial fasciitis differs from nodular fasciitis in that it is associated with the skull bone and, in many cases, the tumor destroys the inner and outer table of the skull and adheres to the dura mater. Cranial fasciitis should be considered to be a variant of nodular fasciitis. Neurosurgeons should be aware of this entity in the differential diagnosis of a firm lesion of the scalp in children. A brief review of the literature disclosed only 17 cases in the world. This case report is the first one of cranial fasciitis in Japan. 相似文献