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991.
PCR primers for the detection of materials derived from ruminants, pigs, and chickens were newly designed on the basis of sequences of the Art2 short interspersed repetitive element (SINE), PRE-1 SINE, and CR1 long interspersed repetitive element (LINE), respectively. These primers amplified the SINE or LINE from total DNA extracted from the target animals and from test feed containing commercial meat and bone meal (MBM). With the primers, detection of Art2, PRE-1, or CR1 in test feed at concentrations of 0.01% MBM or less was possible. This method was suitable for the detection of microcontamination of feed by animal materials.  相似文献   
992.
Cellular injury was evaluated in superfused cerebrocortical slices (350 micro m) from 7-day-old Sprague-Dawley rats exposed to 30 min hypoxia followed by 4 h of reoxygenation. At the end of hypoxia homogenous cytosolic immunoreactivity of cytochrome c increased approximately fourfold, cytochrome c intensity in western blot analyses increased more than fivefold, and whole cell and cytosolic cleaved caspase-9 underwent 50% and 100% increases, respectively. Immunostaining of sections taken 1.5 h after hypoxia showed: (i) more than a threefold increase in cleaved caspase-9; (ii) localization of cleaved caspase-9 to the interior and peripheral exterior of nuclei; and (iii) homogeneously distributed cytochrome c in the cytosol. Western blot analysis for 1.5 h after hypoxia showed that cytosolic caspase-9 returned to control values, while whole cell caspase-9 stayed approximately the same, suggesting translocation of caspase-9 to nuclei. By 4 h after hypoxia there was significant nuclear fragmentation and an increase in TUNEL positive staining. 31P/1H nuclear magnetic resonance (NMR) confirmed substantial decreases of ATP and phosphocreatine during hypoxia, with rapid but incomplete recovery being close to steady state 1 h after reoxygenation. At all time points after hypoxia the primary injury was cytochrome c associated apoptosis.  相似文献   
993.
Membrane orientation induced by an alternating electric field has been examined for the L-enantiomer and racemic dipalmitoylphosphatidylcholine (DPPC) bilayers. The orientation effect was measured by bending curvature of hairpin-like deformation of the multilamellar cylindrical tubes with varying field-strength, frequency and tube size. It has been observed that both L- and DL-DPPC tubes are similar in the profiles of field-strength dependence and frequency dependence on the curvature deformation, but different in the deformed curvatures. DL-DPPC tubes deform largely as compared with L-DPPC tubes. The square of the deformed curvature of DL-DPPC tubes is larger than that of L-DPPC by about 37% on average. The result indicates that the racemic membrane is responsive to the electric field as compared with the L-enantiomer membrane. This suggests that a hybrid arrangement of head groups of the racemic lipid leads an effective response of the membrane due to the head group orientation.  相似文献   
994.
Fast muscle myosin responds in similar way to F-actin and to phalloidin F-actin. It is activated 7.5 fold at infinite F-actin concentration and 6.8 fold at infinite phalloidin F-actin. The actomyosin dissociation constants are 0.89 +/- 0.34 microM with F-actin and 0.90 +/- 0.71 microM with phalloidin F-actin. Slow muscle myosin responds differently to F-actin and to phalloidin F-actin. It is activated 3.76 fold at infinite F-actin concentration and only 2.27 fold at infinite phalloidin F-actin concentration. The actomyosin dissociation constants are 1.95 +/- 1.27 microM with F-actin and 0.27 +/- 0.16 microM with phalloidin F-actin. At first glance this means that substitution of F-actin with phalloidin F-actin magnifies the difference between fast muscle and slow muscle myosins. Furthermore the change of the dissociation constants may affect the contractile force of the attached crossbridge.  相似文献   
995.
 Antibody-dependent cell-mediated cytotoxicity (ADCC) has been considered to be one of the main effector mechanisms by which unconjugated monoclonal antibody (mAb) 17-1A can exert an antitumor effect in vivo. Since the apoptotic pathway as well as the necrotic pathway have been shown to be utilized in various cytotoxic effector mechanisms, we investigated the role of apoptosis in ADCC mediated by monocytes (ADMC) using mAb 17-1A as an antibody and the human colorectal carcinoma cell line, COLO205, as target cells in vitro. The implications of the apoptosis during ADMC was demonstrated by means of both a DNA fragmentation assay and a TdT-mediated dUTP-biotin nick end labeling (TUNEL) assay. Furthermore, interferon γ (IFNγ) was also found to enhance the induction of apoptosis significantly. The addition of superoxide dismutase did not reduce the level of the apoptosis, although superoxide anion (O2 ) was observed to be produced. However, the release of tumor necrosis factor α (TNFα) was significantly enhanced during ADMC, while, in addition, apoptosis was significantly inhibited by the addition of anti-TNFα antibody. These findings indicated that apoptosis might be implicated in ADMC with mAb 17-1A, which was augmented by IFNγ, while, in addition, TNFα may also be one of the major mediators of apoptosis. Received: 1 August 1996 / Accepted: 27 August 1996  相似文献   
996.
Summary Continuous production of acetic acid by liquid surface culture ofAcetobacter aceti M7 was investigated using a Multi-Stage Biofilm Reactor (MSBFR) composed of ten shallow flow horizontal reactors of laboratory scale. With varying dilution rate in the range from 0.049 to 0.2 h–1, the maximum exit acetic acid concentration reached was as high as 98.0 g/l at the lowest dilution rate with step feed of ethanol-rich medium to stages 3, 5, and 7. The production rate (4.3 g/l/h) was rather high considering the inhibitory effect of high acetic acid concentration. This may be ascribed to non-homogeneous distribution of acetic acid concentration in the bioreactor and step feed of ethanol-rich medium.  相似文献   
997.
998.
999.
The cytologic finding of malignant lymphoma cells in the urine and hydrocele fluid of a 32-year-old man is reported. The tumor cells were scattered singly and were slightly larger than normal lymphocytes. Their nuclei were ovoid or irregular in shape. Hyperchromasia, coarsely distributed chromatin and prominent nucleoli were characteristic. Histologic examination showed a non-Hodgkin's malignant lymphoma, corresponding to the large-cell type of diffuse lymphoma.  相似文献   
1000.
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