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191.
192.

Introduction

The objective was to characterize the clinical and myopathologic features of patients with scleroderma-polymyositis (SSc-PM) overlap compared with a population of patients with systemic sclerosis (SSc) and polymyositis (PM).

Methods

A three-way comparison of patients with SSc-PM overlap (n = 25) with patients with SSc (n = 397) and PM (n = 40) on clinical and myopathologic features and causes of death. One neuropathologist blinded for the diagnosis evaluated all recent available muscle biopsies. Biopsies were scored for presence of inflammation, necrotic muscle fibers, rimmed vacuoles, fibrosis, and immunohistochemical staining. Clinical or myopathologic characteristics were compared by using the χ2 test or one-way analysis of variance (ANOVA).

Results

The prevalence of SSc-PM overlap in the Nijmegen Systemic Sclerosis cohort was 5.9%. The mortality was 32% (eight of 25) in SSc-PM, of which half was related to cardiac diseases. The prevalence of pulmonary fibrosis was significantly increased in SSc-PM (83%) (P = 0.04) compared with SSc (49%) and PM (53%). SSc or myositis-specific antibodies were nearly absent in the SSc-PM group. In almost all biopsies (96%) of SSc-PM patients, necrotic muscle fibers were present, which was significantly increased compared with PM patients (P = 0.02).

Conclusions

Patients with SSc-PM have increased prevalence of pulmonary fibrosis and cardiac disease as the cause of death compared with patients with SSc and PM . In addition, we found that necrotizing muscle fibers with inflammation characterize SSc-PM overlap in muscle biopsies. Further research should focus on underlying mechanisms causing necrosis, inflammation, and fibrosis and their relation to pulmonary involvement and mortality in patients with SSc-PM overlap.  相似文献   
193.
长春净月潭地区土壤跳虫的生态分布   总被引:8,自引:1,他引:8  
陈鹏  田中真悟 《昆虫学报》1990,33(2):219-226
土壤动物直接参与土壤形成,它与土壤微生物的相互配合,对植物凋落物的分解起着十分重要的作用。土壤跳虫是土壤动物中最重要的类群之一。关于它的生态分布,目前国内报道不多。东北师范大学和日本九州大学合作,对长春净月潭地区的土壤跳虫进行了初步调查。  相似文献   
194.
A systematic molecular phenotyping approach based on two-dimensional gel electrophoresis is being applied in an attempt to identify protein changes associated with malignant transformation. Using the C3H10T1/2 mouse cell line, two-dimensional polypeptide maps of the non-transformed cell line, several chemically transformed lines and a tumour cell line were compared. Although there is a large degree of similarity between the protein profiles of all cell lines, clear differences are evident. Initial results are consistent with the view that many of the protein changes are incidental to malignant transformation. Changes induced by 3-methylcholanthrene are retained after transplantation of the cells into nude mice.  相似文献   
195.
1. Complement fixation is obtained in every antigen-antibody reaction involving the presence or formation of a heterogeneous phase (red cells, bacteria, precipitate). 2. The physical constants of fixation (temperature coefficient, velocity, quantitative relationships between the reactants) are those commonly associated with adsorption processes, and are the same in the three types of fixation studied. 3. All the in vitro immune reactions involve an aggregation of immune-serum globulins upon the surface of the antigen. It has been shown that the "fixation" of complement is an adsorption by the aggregates so formed; whether these aggregates are visible as a flocculent precipitate (e.g., sheep serum vs. anti-serum) or concentrated as a surface film on a cellular antigen (sensitized cells; agglutinated bacteria), the reaction is fundamentally the same. 4. As yet, it is unknown whether this adsorption is determined by the physical state of the precipitate, and thus, differs only quantitatively from that by Kaolin, charcoal, normal bacteria, heat-denatured proteins, etc.; or whether the comparatively enormous avidity of these aggregates for complement is due to a specific chemical affinity.  相似文献   
196.
Summary The efficiency of various coupling methods for the incorporation of the three monobenzyl phosphorodiesterprotected derivatives, Fmoc-Tyr(PO3Bzl,H)-OH, Fmoc-Ser(PO3Bzl,H)-OH and Fmoc-Thr(PO3Bzl,H)-OH, was examined through the test synthesis of Ala-Ser-Gln-Gly-Xxx(PO3H2)-Leu-Glu-Asp-Pro-Ala-NH2 (Xxx=Tyr, Ser, Thr) using the Multipin method of multiple peptide synthesis. The coupling methods examined were (1) PyBrop/DIEA; (2) BOP/HOBt/NMM; (3) BOP/HOBt/DIEA; (4) HBTU/HOBt/DIEA; (5) HATU/HOAt/DIEA; (6) HATU/DIEA; (7) DIC/HOBt; (8) DIC/HOBt/DIEA; (9)DIC/HOAt; (10) DIC/HOAt/DIEA. While all four DIC-based coupling procedures resulted in incomplete incorporation, both the HBTU/HOBt/DIEA and HATU/HOAt/DIEA coupling procedures provided most efficient incorporation of the three Fmoc-Xxx (PO3Bzl,H)-OH derivatives. In the subsequent synthesis of the α-helical Tyr(P)-peptide, Glu-Thr-Gly-The-Lys-Ala-Glu-Leu-Leu-Ala-Lys-Tyr(PO3H2)-Glu-Ala-Thr-His-Lys-NH2, analysis of the crude peptide by electrospray MS confirmed that several residue deletions had occurred but that complete incorporation of the Tyr(P)-residue had been accomplished using HBTU/HOBt/DIEA coupling of Fmoc-Tyr(PO3Bzl,H)-OH. Multipin is a trademark of Chiron Technologies Pty. Ltd., Clayton, Victoria, Australia.  相似文献   
197.
198.
Book reviews     
  相似文献   
199.
The effect of environmental pH on the growth of normal and malignant cells   总被引:6,自引:0,他引:6  
Data have been presented with respect to the widely varying pH optima for the growth of a number of normal and transformed human, mouse, monkey, hamster, rabbit and rat cell lines. At that optimum, differences between normal and transformed cells with respect to maximum population densities tended to become less prominent. Other differences (serum requirement, long-term viability of cultures) were not demonstrably pH-dependent.  相似文献   
200.
The solid phase synthesis of a set of peptide aldehydes derived from the NS5A/NS5B junction of hepatitis C virus (HCV) viral polyprotein is demonstrated using an oxazolidine linker and the Multipin method. Deletion of the P6 and P5 residues results in a dramatic loss of inhibitory activity.  相似文献   
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