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11.
The population of peripheral blood lymphocytes expressing surface receptors for a lectin, wheat germ agglutinin (WGA), which has been shown to recognize the same receptors as the soluble immune suppressor factor (SISF) elaborated from suppressor cells on the lymphocyte surface, was analyzed by using fluorescein isothiocyanate-conjugated WGA on flow cytometry in cancer patients. It was found that the populations of WGA+ lymphocytes in cancer patients were significantly higher than those in either normal volunteers or patients with benign disease and increased with progress of the tumor. The populations decreased after treatment in patients who underwent curative resection of the tumor and in responders of immunochemotherapy but not in those who received non-curative surgery or in non-responders. It was suggested that the increase of receptors for SISF on the lymphocyte surface might play an important role in the negative regulation of immune responses in cancer patients and that WGA might be a useful parameter for immunosuppression.  相似文献   
12.
The negative inotropic effects of oxybarbiturates and thiobarbiturates were examined in papillary muscles isolated from streptozotocin-induced diabetic rats and in papillary muscles from age-matched control rats. The muscles from diabetic rats exhibited less negative inotropic responses to pentobarbital and secobarbital than the muscles from control rats. Conversely, the negative inotropic responses to thiopental and thiamylal were significantly enhanced in diabetic muscles. Differences in sensitivity to pentobarbital between control and diabetic muscles became less marked by treatment with ouabain or by lowering [Na+]o. Enhancement of the negative inotropic effect of thiamylal observed in diabetic muscles remained unchanged with these treatments. In both control and diabetic muscles, the negative inotropic effect of pentobarbital was completely reversed by increasing [Ca2+]o, but the effect of thiamylal was only partially reversed. These results suggest a difference in mechanism of action involved in establishment of the negative inotropic effects of oxybarbiturates vs thiobarbiturates. Oxybarbiturates appear to exclusively reduce the influx of extracellular Ca2+, whereas thiobarbiturates appear to affect Ca2+ movements at the Ca2+ storage sites in addition to the Ca2+ influx inhibition.  相似文献   
13.
We studied subsets and cytotoxicity of recombinant interleukin-2 (rIL-2) expanded tumor infiltrating lymphocytes (TIL) from renal cell cancer (RCC) patients. TIL were successfully expanded in 13 of 14 RCC cases using anti-CD3 during initial 48 hours of culture. Percentages of CD8 positive cells among rIL-2 expanded TIL at 1 tp 4 week(s) of culture were 56.2 +/- 15.1% (range 26.2 to 79.8%, N = 13) and not necessarily predominant over CD4 positive cells. NK and LAK activities of TIL at 3 to 6 weeks of culture were 31.6 +/- 15.8% (range 1.4 to 57.4%, N = 9) and 16.6 +/- 11.6% (range 3.8 to 35.6%, N = 6), respectively. Autologous and allogeneic RCC cytotoxicity of TIL at 3 to 4 weeks of culture were 17.9 +/- 19.7% (range 0 to 47.6%, N = 4) and 18.9 +/- 14.8% (range 0 to 47.3%, N = 12), respectively. Since there was no statistical difference between them, autologous specific cytotoxicity was not demonstrated. From these results of present study, it is unlikely that most of effector cells of rIL-2 expanded TIL in autologous RCC lysis are major histocompatibility complex restricted cytotoxic T cells. And we concluded that it is doubtful that TIL is significantly superior over LAK cells in immunotherapy of human RCC.  相似文献   
14.
Our aim was to find a simple method of removing labile glycosylated hemoglobin (HbA1c) from blood samples before it is measured by cation-exchange chromatography. Labile HbA1c is formed by the binding of glucose to the NH2-terminal valine of the beta-chain of HbA. We sought a more competitive binder for the same site to dissociate labile HbA1c to glucose and HbA. Inorganic phosphates were found to have a strong allosteric effect and a great ability to eliminate labile HbA1c. We developed our method with 4 mM tetrapolyphosphate in the hemolyzing solution to eliminate labile HbA1c during the automatic processing (at pH 6 and heated for 2 min at 45 degrees C) of blood samples for HbA1c estimation. This may be useful when estimating HbA1c by the manual method.  相似文献   
15.
Background: Although isoflurane, a volatile anesthetic, can block the motor response to noxious stimulation (immobility and analgesia) and suppress autonomic responsiveness, how it exerts these effects at the neuronal level in the spinal cord is not fully understood.

Methods: The effects of a clinically relevant concentration (1 rat minimum alveolar concentration [MAC]) of isoflurane on electrically evoked and spontaneous excitatory/inhibitory transmission and on the response to exogenous administration of the [gamma]-aminobutyric acid type A receptor agonist muscimol were examined in lamina II neurons of adult rat spinal cord slices using the whole cell patch clamp technique. The effect of isoflurane on the action potential-generating membrane property was also examined.

Results: Bath-applied isoflurane (1.5%, 1 rat MAC) diminished dorsal root-evoked polysynaptic but not monosynaptic excitatory postsynaptic currents. Glutamatergic miniature excitatory postsynaptic currents were also unaffected by isoflurane. In contrast, isoflurane prolonged the decay phase of evoked and miniature [gamma]-aminobutyric acid type A receptor-mediated inhibitory postsynaptic currents and increased the amplitude of the muscimol-induced current. Isoflurane had little effect on action potential discharge activity.  相似文献   

16.
During the course of our studies on dental caries prevention by traditional medicines, fatty acids (myristic and oleic acids etc.) and procyanidins from betel nuts (the seed of Areca catechu L.) were respectively revealed to be the major antibacterial principles against a primary cariogenic bacterium, Streptococcus mutans, and the major inhibitory principles against glucosyltransferase from S. mutans.  相似文献   
17.
Ryo Hattori  MD    Tateki Kubo  MD    Kenji Yano  MD  PhD    Atsushi Tanemura  MD    Yuji Yamaguchi  MD  PhD    Satoshi Itami  MD  PhD    Ko Hosokawa  MD  PhD 《Dermatologic surgery》2003,29(10):1071-1072
BACKGROUND: Nevus lipomatosus cutaneous superficialis (NLCS) is a relatively rare condition. Although NLCS can affect any region of the entire body, no case of NLCS in the clitoris has ever been reported. OBJECTIVE: To report a case of NLCS of the clitoris that presented manifestations that were similar to female pseudohermaphrodism. METHODS: This is a case report and review of the literature. RESULTS: A congenital, soft, skin-colored lesion of the clitoris in a 1-year-old girl resembled female pseudohermaphrodism. It was resected, and the histologic diagnosis was NLCS. Postoperatively, there was no subsequent change in the lesion during the 3-year follow-up period. CONCLUSION: We reported a case of congenital solitary NLCS of the clitoris. Although NLCS might be a relatively rare condition, we should consider it in the differential diagnosis of female pseudohermaphrodism.  相似文献   
18.
Photoaging and oxidative stress   总被引:5,自引:0,他引:5  
  相似文献   
19.
We have constructed the recombinant baculovirus which expresses the human immunodeficiency virus type 1 negative factor (nef) gene. Spodoptera frugiperda cells infected with the recombinant virus produced a 27-kDa protein which reacted with rabbit antisera raised against a carboxy-terminal synthetic peptide of the Nef protein by immunoblot analysis. Labeling experiment showed that the recombinant Nef protein was myristoylated. The recombinant Nef protein was purified to near homogeneity by DEAE-Sephacel, phenyl-Sepharose 4B, blue-Sepharose, and Sephadex G-150 column chromatography. No detectable GTP binding activity was observed in the purified recombinant Nef product.  相似文献   
20.
The electrophysiological actions of SUN 1165 on isolated guinea pig atrial and papillary muscles, canine Purkinje fibers, and rabbit sinoatrial node were studied using standard microelectrode techniques. SUN 1165 in low (10(-7) g/ml) concentration had little effect on any of the action potential parameters measured. Intermediate (10(-6) g/ml) concentration of the compound shortened the duration of action potential of canine Purkinje fibers and increased ratio of the effective refractory period to the duration of action potential at 90% repolarization in guinea pig atrial muscles. At high (10(-5) g/ml) concentration, the compound reduced the maximum rate of rise of phase 0 in guinea pig atrial, papillary muscles, and canine Purkinje fibers, though the change in the latter was not statistically significant, and also decreased the action potential amplitude in guinea pig atrial muscles and canine Purkinje fibers. At all concentrations (10(-7)-10(-5) g/ml) tested, the compound exerted little effect both on spontaneous action potentials in rabbit sinoatrial node cells and on Ca2+-mediated slow responses in partially depolarized guinea pig papillary muscles. These results indicate that SUN 1165 may selectively inhibit cardiac sodium channels and is likely to be of value in correcting not only ventricular but also supraventricular tachyarrhythmias.  相似文献   
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