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21.
Polyketones with carbonyl groups in the polymer backbone (ethylene-carbon monoxide copolymer) have been converted into a novel polyoxime by means of C-nitrosation of the methylene groups and oximation of the carbonyl groups. The polyoxime is considered to be composed largely of 1,2-bis(hydroxyimino)trimethylene units. From the polyoxime and divalent Fe-, Co-, or Ni-salts, polymeric metal chelate complexes were prepared which are capable of combining reversibly with molecular oxygen and, especially the Fe-complex, also with carbon monoxide.  相似文献   
22.
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy.  相似文献   
23.
Scrotal leiomyomas with atypical bizarre nuclei are rare, which might be misdiagnosed as malignant tumor. We describe a case of scrotal bizarre leiomyoma in a 65-yr-old man. The tumor was a 1 cm-sized, well circumscribed, oval mass arising from the tunica dartos muscle. Histologically, it was formed by whorling bundles of fusiform cells with occasional atypical, pleomorphic nuclei and pseudo-inclusions. Mitosis was not found. Although morphologically atypical, scrotal bizarre leiomyomas take on a biologic behavior not different from that of conventional leiomyoma, they should be distinguished from leiomyosarcoma to avoid unnecessary treatment.  相似文献   
24.
The herbal formulation "Jeo Dang-Tang" (JDT) has long been used for various cerebrovascular diseases. However, very little has scientific investigation been carried out. The aim of the present study is to investigate the effect of JDT on the production of various cytokines in the patients with cerebral infarction (CI). Peripheral blood mononuclear cells (PBMC) obtained from the patients with CI were cultured for 24h in the presence or absence of lipopolysaccharide (LPS) or phytohemagglutinin (PHA). The amount of interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-1beta, in culture supernatant, was significantly increased in the JDT, LPS or PHA treated cells compared to unstimulated cells (P < 0.05). We also show that increased IL-4, and IL-10 level by LPS or PHA was significantly inhibited by JDT in a dose-dependent manner. Maximal inhibition rate of IL-4 and IL-10 production by JDT was 45 +/- 2% and 51 +/- 5% for LPS-stimulated cell and 41.5 +/- 3% and 70.8 +/- 2% for PHA-stimulated cells, respectively (P < 0.05). On the other hand, JDT significantly increased the LPS or PHA-induced TGF-beta1 production (P < 0.05). These data suggest that JDT has a regulatory effect on the cytokines production, which might explain its beneficial effect in the treatment of CI.  相似文献   
25.
BACKGROUND: Severe acute respiratory syndrome (SARS) became a worldwide outbreak with a mortality of 9.2%. This new human emergent infectious disease is dominated by severe lower respiratory illness and is aetiologically linked to a new coronavirus (SARS-CoV). METHODS: Pulmonary pathology and clinical correlates were investigated in seven patients who died of SARS in whom there was a strong epidemiological link. Investigations include a review of clinical features, morphological assessment, histochemical and immunohistochemical stainings, ultrastructural study, and virological investigations in postmortem tissue. RESULTS: Positive viral culture for coronavirus was detected in most premortem nasopharyngeal aspirate specimens (five of six) and postmortem lung tissues (two of seven). Viral particles, consistent with coronavirus, could be detected in lung pneumocytes in most of the patients. These features suggested that pneumocytes are probably the primary target of infection. The pathological features were dominated by diffuse alveolar damage, with the presence of multinucleated pneumocytes. Fibrogranulation tissue proliferation in small airways and airspaces (bronchiolitis obliterans organising pneumonia-like lesions) in subpleural locations was also seen in some patients. CONCLUSIONS: Viable SARS-CoV could be isolated from postmortem tissues. Postmortem examination allows tissue to be sampled for virological investigations and ultrastructural examination, and when coupled with the appropriate lung morphological changes, is valuable to confirm the diagnosis of SARS-CoV, particularly in clinically unapparent or suspicious but unconfirmed cases.  相似文献   
26.
Antiphospholipid syndrome (APS) is an autoimmune disease that is characterized by thrombosis, recurrent fetal loss and thrombocytopenia. Antiphospholipid antibodies, detected by enzyme-linked immunoabsorbent assays (aCL) and/or in vitro blood clotting assays (LAC) are strongly associated with APS. Both the molecular structures used by pathogenic antiphospholipid antibodies and the genetic mechanisms leading to their production are unknown. We describe here the variable region genes of seven IgG antiphospholipid antibodies derived from two APS patients. Of these, five are pathogenic as defined in a mouse model of thrombosis and two are not. Analyses of the expressed variable region genes show no preferential V gene usage. However, similar to anti-DNA antibodies, pathogenic antiphospholipid antibodies contain an increased number of arginine residues in the third complimentarity-determining region (CDR3) of their H chains. The increased accumulation of arginine residues in the V(H) CDR3 may act to enhance antigen binding, promote disease and point to the importance of the H chain in the pathogenic potential of certain antiphospholipid antibodies.  相似文献   
27.
The long half-life and stability of human serum albumin (HSA) make it an attractive candidate for fusion to short-lived therapeutic proteins. Albuferon (Human Genome Sciences [HGS], Inc., Rockville, MD) beta is a novel recombinant protein derived from a gene fusion of interferon-beta (IFN-beta ) and HSA. In vitro, Albuferon beta displays antiviral and antiproliferative activities and triggers the IFN-stimulated response element (ISRE) signal transduction pathway. Array analysis of 5694 independent genes in Daudi-treated cells revealed that Albuferon beta and IFN-beta induce the expression of an identical set of 30 genes, including 9 previously not identified. In rhesus monkeys administered a dose of 50 microg/kg intravenously (i.v.) or subcutaneously (s.c.) or 300 microg/kg s.c., Albuferon beta demonstrated favorable pharmacokinetic properties. Subcutaneous bioavailability was 87%, plasma clearance at 4.7-5.7 ml/h/kg was approximately 140-fold lower than that of IFN-beta, and the terminal half-life was 36-40 h compared with 8 h for IFN-beta. Importantly, Albuferon beta induced sustained increases in serum neopterin levels and 2',5' mRNA expression. At a molar dose equivalent to one-half the dose of IFN-beta, Albuferon beta elicited comparable neopterin responses and significantly higher 2',5'-OAS mRNA levels in rhesus monkeys. The enhanced in vivo pharmacologic properties of IFN-beta when fused to serum albumin suggest a clinical opportunity for improved IFN-beta therapy.  相似文献   
28.
Heme-hemopexin (2-10 microM) is used as a model for intravenous heme released in trauma, stroke, and ischemia-reperfusion. A transient increase in cellular protein oxidation occurs during receptor-mediated heme transport from hemopexin which is inhibited by the nonpermeable Cu(I) chelator, bathocuproinedisulfonate. Thus, participation of surface redox process involving Cu(I) generation are proposed to be linked to the induction of the protective proteins heme oxygenase-1 (HO-1) and metallothionein-1 (MT-1) by heme-hemopexin. The region (-153 to -42) in the proximal promoter of the mouse MT-1 gene responds to heme- and CoPP-hemopexin in transient transfection assays and contains metal-responsive elements for MTF-1 and an antioxidant-responsive element (ARE) overlapping a GC-rich E-box to which USF-1 and -2 bind. No decreases in DNA binding of the diamide-oxidation sensitive USF-1 and -2 occur upon exposure of cells to heme-hemopexin. MTF-1 and the ARE-binding proteins are relatively resistant to diamide oxidation and are induced approximately eight- and two-fold, respectively, by heme-hemopexin. BCDS prevents the nuclear translocation of MTF-1 by both heme- and CoPP-hemopexin complexes as well as MT-1 mRNA induction by CoPP-hemopexin. Thus, copper is needed for the surface oxidation events and yet the nuclear translocation of MTF-1 in response to hemopexin occurs via copper, probably Cu(I),-dependent signaling cascades from the hemopexin receptor rather than the oxidation per se.  相似文献   
29.
 Using the whole-cell patch clamp technique, the role of actin microfilament in hyposmotic increase of voltage-operated calcium channel current (I Ba) was studied in guinea-pig gastric myocytes. Hyposmotic superfusate (212 mOsm) increased peak I Ba amplitude by 32.7 ± 6.5%; when cytochalasin-D (Cyt-D, 20 μM), an actin cytoskeleton disruptor, was used, an increase of only 9.7 ± 3.1% was seen. I Baresponse to osmotic stress was potentiated (45.1 ± 4.1% increase) by 20 μM phalloidin, an actin microfilament stabilizer. However, colchicine (100 μM), an microtubule cytoskeleton disruptor, had no effect on either I Ba or its response to hyposmotic solution. Phalloidin also induced a rightward shift of the I/V relationship of I Ba, while Cyt-D itself had no effect. These results suggest that actin cytoskeleton may mediate hyposmotic stretch-induced I Ba increase in gastric smooth muscle. Received: 26 March 1997 / Received after revision: 28 May 1997 / Accepted: 3 June 1997  相似文献   
30.
Several issues remain to be resolved before the efficacy of various approaches to elicit anti-tumor immunity in patients can be evaluated. First, in vitro assays able to detect responses by T cells primed in vivo are needed. Second, a source of tumor antigen to stimulate patients' lymphocytes in vitro is required. The ELISPOT assay is attractive, because it can be performed with a small numbers of cells and requires only short-term culture in vitro. A source of tumor antigen is more problematic, since for most tumors, tumor-associated antigens (TAA) have not been identified and/or cloned. In this report we demonstrate that autologous antigen-presenting cells (APC) pulsed with total tumor peptides from autologous tumor tissue can stimulate IFNgamma release by patients' lymphocytes in the ELISPOT assay. Thus, this approach should be considered for monitoring immune responses in clinical immunotherapy trials.  相似文献   
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