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In 1991, the International Registry of Lung Metastases was formed by 18 thoracic surgery departments in Europe and North America. Statistical analysis of combined data from the Registry revealed significant variables in patient selection, which helped to guide treatment modalities for specific patients. A simple system of stage classification is presented in this article as a basis for discussions on future results and for clinical trial design.  相似文献   
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Golgi soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) GS28 and syntaxin 5 can be reciprocally coimmunoprecipitated from Golgi extracts, suggesting that they exist in a protein complex. When Golgi extract is preincubated with soluble NSF attachment proteins (alpha-SNAP) and N-ethylmaleimide-sensitive factor (NSF) under conditions that allow ATP hydrolysis by NSF, GS28 and syntaxin 5 become dissociated. GS28 and syntaxin 5 remain in a protein complex when Golgi extract is preincubated with similar amounts of alpha-SNAP and NSF under conditions that prevent ATP hydrolysis by NSF, suggesting that ATP hydrolysis by NSF is necessary for dissociating the GS28-syntaxin 5 complex. Since preincubation of Golgi extract with either alpha-SNAP or NSF alone has no effect on the GS28-syntaxin 5 complex, a concerted action of alpha-SNAP and NSF therefore mediates the dissociation of the GS28-syntaxin 5 complex. Furthermore, GS28 but not syntaxin 5 is capable of binding to immobilized alpha-SNAP when the GS28-syntaxin 5 complex is dissociated.  相似文献   
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Mice deficient in the cytokines tumor necrosis factor (TNF) or lymphotoxin (LT) alpha/beta lack polarized B cell follicles in the spleen. Deficiency in CXC chemokine receptor 5 (CXCR5), a receptor for B lymphocyte chemoattractant (BLC), also causes loss of splenic follicles. Here we report that BLC expression by follicular stromal cells is defective in TNF-, TNF receptor 1 (TNFR1)-, LTalpha- and LTbeta-deficient mice. Treatment of adult mice with antagonists of LTalpha1beta2 also leads to decreased BLC expression. These findings indicate that LTalpha1beta2 and TNF have a role upstream of BLC/CXCR5 in the process of follicle formation. In addition to disrupted follicles, LT-deficient animals have disorganized T zones. Expression of the T cell attractant, secondary lymphoid tissue chemokine (SLC), by T zone stromal cells is found to be markedly depressed in LTalpha-, and LTbeta-deficient mice. Expression of the SLC-related chemokine, Epstein Barr virus-induced molecule 1 ligand chemokine (ELC), is also reduced. Exploring the basis for the reduced SLC expression led to identification of further disruptions in T zone stromal cells. Together these findings indicate that LTalpha1beta2 and TNF are required for the development and function of B and T zone stromal cells that make chemokines necessary for lymphocyte compartmentalization in the spleen.  相似文献   
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Atypical cell surface lipoprotein-binding proteins of 105 kDa and 130 kDa are present in membranes of vascular smooth muscle cells. We recently identified the 105 kDa protein from human aortic media as T-cadherin, an unusual glycosylphosphatidylinositol (GPI)-anchored member of the cadherin family of cell adhesion proteins. The goal of the present study was to determine the identity of 130 kDa lipoprotein-binding protein of smooth muscle cells. We applied different approaches that included protein sequencing of purified protein from human aortic media, the use of human T-cadherin peptide-specific antisera, and enzymatic treatment of cultured cells with trypsin and GPI-specific phospholipase C. Our results indicate that the 130 kDa protein is a partially processed form of T-cadherin which is attached to the membrane surface of smooth muscle cells via a GPI anchor and contains uncleaved N-terminal propeptide sequence. Our data disclose that, in contrast to classical cadherins, T-cadherin is expressed on the cell surface in both its precursor (130 kDa) and mature (105 kDa) forms.  相似文献   
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Syntaxin 1, synaptobrevins or vesicle-associated membrane proteins, and the synaptosome-associated protein of 25 kDa (SNAP-25) are key molecules involved in the docking and fusion of synaptic vesicles with the presynaptic membrane. We report here the molecular, cell biological, and biochemical characterization of a 32-kDa protein homologous to both SNAP-25 (20% amino acid sequence identity) and the recently identified SNAP-23 (19% amino acid sequence identity). Northern blot analysis shows that the mRNA for this protein is widely expressed. Polyclonal antibodies against this protein detect a 32-kDa protein present in both cytosol and membrane fractions. The membrane-bound form of this protein is revealed to be primarily localized to the Golgi apparatus by indirect immunofluorescence microscopy, a finding that is further established by electron microscopy immunogold labeling showing that this protein is present in tubular-vesicular structures of the Golgi apparatus. Biochemical characterizations establish that this protein behaves like a SNAP receptor and is thus named Golgi SNARE of 32 kDa (GS32). GS32 in the Golgi extract is preferentially retained by the immobilized GST-syntaxin 6 fusion protein. The coimmunoprecipitation of syntaxin 6 but not syntaxin 5 or GS28 from the Golgi extract by antibodies against GS32 further sustains the preferential interaction of GS32 with Golgi syntaxin 6.  相似文献   
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This article examines metrological aspects of the problem of improving the accuracy of measurement of heat energy and reducing the imbalances between suppliers and consumers. Metrological requirements are formulated for different blocks of a measurement system along with standards for their substantiation. The metrological characteristics of the components that meter heat, energy are calculated by computer programs on the basis of the actual systematic errors of the corresponding blocks. Translated from Izmeritel'naya Tekhnika, No. 1, pp. 36–39, January, 1999.  相似文献   
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