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991.
992.
A novel concept for assembling various chemical functions onto a single microfluidic device is proposed. The concept, called a capillary-assembled microchip, involves embedding chemically functionalized capillaries into a lattice microchannel network fabricated on poly(dimethylsiloxane) (PDMS). The network has the same channel dimensions as the outer dimensions of the capillaries. In this paper, we focus on square capillaries to be embedded into a PDMS microchannel network having a square cross section. The combination of hard glass square capillary and soft square PDMS channel allows successful fabrication of a microfluidic device without any solution leakage, and which can use diffusion-based two-solution mixing. Two different types of chemically modified capillaries, an ion-sensing capillary and a pH-sensing capillary, are prepared by coating a hydrophobic plasticized poly(vinyl chloride) membrane and a hydrophilic poly(ethyleneglycol) membrane containing functional molecules onto the inner surface of capillaries. Then, they are cut into appropriate lengths and arranged on a single microchip to prepare a dual-analyte sensing system. The concept proposed here offers advantages inherent to using a planar microfluidic device and of chemical functionality of immobilized molecules. Therefore, we expect to fabricate various types of chemically functionalized microfluidic devices soon.  相似文献   
993.
New amphoteric surfactants of N-(3-alkoxy-2-hydroxypropyl)-N-(2-hydroxyethyl)-β-alanine (APA) have been synthesized. The fundamental surface-active properties (critical micelle concentration and isoelectric point) and hemolysis tests were also investigated to examine the effects of differences in chain length of the alkoxy moiety. The hemolysis result of APA exhibited low constant values irrespective of the alkyl chain length. The amphoteric APA surfactant was confirmed to have a mild effect on human microorganisms and to possess excellent surface-active properties. In addition, a speculative model of micelle configuration was estimated by semiempirical molecular orbital simulations.  相似文献   
994.
After the short summary of investigation methods of latent Squint the authors report about the method using the standard Trial Frame Okula and prism with a power of 16 pdpt, with Maddox lens from common trial case Okula. This method is used for an indication of magnitude of latent Squint for a short and a long distance. After the meaning of the authors is exoforia for a short distance one of the most frequent causes of muscular asthenopic disorders.  相似文献   
995.
996.
We cloned the canine interleukin-12 (IL-12) subunit cDNA. Canine IL-12 exhibited sequence homology to the known sequences of human, mouse, and bovine genes at nucleotide and amino acid levels. Cotransfection of the p35 and p40 subunits of canine IL-12 cDNA clones into COS-1 cells resulted in the secretion of IL-12, which supported proliferation of the stimulated canine lymphocytes, promoted induction of canine interferon-gamma (IFN-gamma) from canine lymphocytes, and showed antitumor effect in vitro. The cloned canine IL-12 will be useful for canine therapeutic applications.  相似文献   
997.
Prolonged hypoxia induced transient drug resistance in Chinese hamster lung fibroblasts. Previously hypoxic cells were resistant to adriamycin and resistant to etoposide. Complete recovery of etoposide sensitivity was observed following reaeration for 24 hr. A change in P-glycoprotein expression was unlikely to contribute to the resistance caused by hypoxia, since adriamycin resistance was not reversed by verapamil. However, alteration in the plasma membrane structure may be involved, since previously hypoxic cells were resistant to extracellular superoxide radical generated by the addition of xanthine/xanthine oxidase. In contrast, adriamycin sensitivity was not altered by hypoxia in 3 human breast-cancer cell lines. MDA-468 and MCF-7/Adr differed in their response to EGF, independent of the presence of hypoxia. These results suggest that hypoxic-stress-induced drug resistance is not generalized.  相似文献   
998.
Primary hepatic lymphoma is a rare disorder and the clinical behavior remains unknown. We report a patient with primary hepatic lymphoma who had chronic hepatitis B. She was asymptomatic; however, a solitary tumor in the left lobe was incidentally detected. After left hepatic lobectomy was performed, a diagnosis of non-Hodgkin's lymphoma was made. No tumor was found except in the liver. Immunohistochemical stains for hepatitis B surface and core antigens were positive in hepatocytes; however, both were negative in the tumor tissue. The patient received no chemotherapy and the tumor relapsed. After chemotherapy, the tumor disappeared. However, exacerbation of hepatitis occurred after the fourth chemotherapy. The patient was followed up without chemotherapy, and she remains in apparent remission. Chemotherapy is effective against primary hepatic lymphoma and, if possible, patients with this disorder should be treated with chemotherapy postoperatively.  相似文献   
999.
BACKGROUND: For evaluating pancreaticobiliary stenoses during endoscopic retrograde cholangiopancreatography (ERCP) tissue sampling techniques may be important. Brush cytology and forceps biopsy during ERCP are two potential, but so far only incompletely evaluated, tools for the diagnosis of malignant biliary or pancreatic stenoses. METHODS: Between 1992 and 1995 we acquired 133 cytologic and/or histologic samples from 119 patients who underwent ERCP because of biliary duct stenoses. Sixteen patients had to be excluded from the study due to insufficient follow-up information. After papillotomy, brush cytology was performed in 65 cases (63 patients), and forceps biopsy in 119 cases (106 patients under fluoroscopic guidance. Both methods were applied in combination 51 times (48 patients). The nature of the stenoses was confirmed by surgery, autopsy, or by the subsequent clinical course. RESULTS: The sensitivity was 46.7% for brush cytology and 64.9% for forceps biopsy. The combined application of both methods resulted in superior sensitivity (70.4%). Specificity was 100% for all methods. CONCLUSIONS: These numbers lead us to recommend a combined and more frequent application of brush cytology and forceps biopsy of bile duct stenoses to enhance the diagnostic yield whenever substantial influence on therapy can be expected.  相似文献   
1000.
The effect of cycloheximide (CHX) on the gene expression for inducible NO synthase (iNOS), interferon (IFN)-beta, and IFN regulatory factor (IRF)-1 was examined in LPS-stimulated J774 macrophages. LPS caused increased expression of mRNAs specific for iNOS, IFN-beta, and IRF-1 with different kinetics. Addition of CHX resulted in inhibition of the LPS-induced iNOS gene expression and parallel decrease in NO production. In contrast, expression of IFN-beta and IRF-1 genes in response to LPS was potentiated in the presence of CHX. These results indicate that de novo protein synthesis is not required for IFN-beta and IRF-1 gene expression and that ongoing protein synthesis including IFN-beta and IRF-1 may be involved in the induction process of iNOS in mouse macrophages.  相似文献   
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