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排序方式: 共有7125条查询结果,搜索用时 62 毫秒
101.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献
102.
Hepatic reticuloendothelial system activation in autoimmune mice: differences between (NZB X NZW)F1 and MRL-lpr/lpr strains 总被引:3,自引:0,他引:3
D B Magilavy T R Hundley A D Steinberg I M Katona 《Clinical immunology and immunopathology》1987,42(3):386-398
5'-Nucleotidase (5'N) activity and Ia expression of hepatic nonparenchymal cells (NPCs) of the autoimmune (NZB X NZW)F1 and MRL-lpr/lpr and nonautoimmune C3H/FeJ, DBA/2J, and A/J strains were assayed to determine endogenous activation of the hepatic reticuloendothelial system (RES). Pretreatment of the nonautoimmune strains with Corynebacterium parvum resulted in decreases in Fc receptor expressor and 5'N and an increase in Ia expression of NPCs. Endogenous hepatic RES activation, as measured by low 5'N and high Ia expression, was observed in both the autoimmune MRL-lpr/lpr and (NZB X NZW)F1 strains even without C. parvum pretreatment. However, in the MRL-lpr/lpr strain, age is a dependent variable in activation and correlates with delayed clearance from the circulation of soluble IgG immune complexes. In the (NZB X NZW)F1 strain, the observation of decreased 5'-nucleotidase activity and increased percentage of Ia-positive cells at all ages suggests a primary abnormality. Therefore, different genetic or exogenous factors may be responsible for the activation of the hepatic RES in these autoimmune strains. 相似文献
103.
A male infant is described in whom congenital anomalies were recognized prenatally by ultrasound examination. The infant was delivered following spontaneous labor and died approximately 15 min after birth. An autopsy revealed major anomalies in the central nervous system (holoprosencephaly with premaxillary agenesis), the gastrointestinal system (esophageal atresia) and the heart (tetralogy of Fallot). Chromosomal studies revealed recombinant chromosome 5 [46,XY, rec(5), dup q, inv(5)(p15q32)], resulting in partial trisomy 5q and partial monosomy 5p. Cytogenetic investigation of the family revealed a pericentric inversion of chromosome 5 in the father and paternal grandmother, 46,XY (and XX, respectively,) inv(5)(p15q32). The congenital anomalies in this infant are more extensive and severe than previously reported in cases of recombination aneusomy involving chromosome 5. 相似文献
104.
Moretti S Marcellini S Boschini A Famularo G Santini G Alesse E Steinberg SM Cifone MG Kroemer G De Simone C 《Clinical and experimental immunology》2000,122(3):364-373
This study was designed to compare the degree of lymphocyte apoptosis and Fas-Fas ligand (FasL) expression in AIDS patients and long-term non-progressors (LTNPs) and correlate these parameters with apoptosis-associated perturbations in lymphocyte function. LTNPs had a lower frequency of apoptotic CD4+ and CD8+ T cells compared with subjects with AIDS. This correlated with a lower frequency of cells expressing Fas and FasL. The frequency of selected lymphocyte populations exhibiting a disrupted mitochondrial transmembrane potential (DeltaPsim) and increased superoxide generation was lower in LTNPs than in patients with AIDS; these abnormalities were associated with lower levels of caspase-1 activation in LTNPs. The results indicate a significantly reduced level of apoptosis and apoptosis-associated parameters in LTNPs than in patients developing AIDS. Based on these findings, a crucial role for mitochondria can be predicted in the process of lymphocyte apoptosis during the evolution of AIDS. 相似文献
105.
106.
The DNA of the human serum amyloid A (SAA) gene GSAA1 contains several repetitive regions within its introns. We have studied length variations at one such region in the 2nd intron by selective amplification using the polymerase chain reaction (PCR) and defined oligonucleotide primers. The lengths of the repetitive regions frequently differ between individual chromosomes and can be transmitted as Mendelian markers, making them useful for genetic linkage analysis. 相似文献
107.
Peter A. Shapiro Richard P. Sloan Emilia Bagiella J. Thomas Bigger JR. Jack M. Gorman 《Psychophysiology》1996,33(1):54-62
Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation. 相似文献
108.
IgG antibody to gE, the Fc gamma-binding herpes simplex 1 (HSV-1) viral glycoprotein, was studied in 49 rheumatoid arthritis (RA) patients and 43 normal controls. Antibody to gD, another important HSV-1 antigen, was assayed in parallel. No difference between RA patients and normal controls was found in levels of anti-gE antibody measured by reactivity of IgG F(ab')2 fragments reacting with gE coated to ELISA plates. No difference in anti-gD antibody was recorded between normals and patients with RA. Levels of IgG anti-IgE antibody did not correlate with quantitative elevations of serum rheumatoid factor (RF) in RA patients. When IgG anti-gE and anti-gD were assayed in 20 patients with juvenile rheumatoid arthritis and 22 children controls, no significant differences were noted. However, when individual RFs from patients with RA were tested for reactivity against a panel of affinity-isolated F(ab')2 antibodies to gE, some evidence for individual autospecificity was obtained. Four of 20 monoclonal IgM RFs produced from RA patients' B cells showed marked elevations of reactivity with some RA patients' F(ab')2 antibodies to gE. All four of the monoclonal RFs showing this specificity were derived from RA synovial tissue B cells. These findings may provide support for the concept that some RFs in patients with RA show individual specificity for internal image determinants of IgG antibodies to viral Fc gamma-binding proteins. 相似文献
109.
M E Gershwin W Glinski A N Bender S P Ringel A D Steinberg W K Engel 《International archives of allergy and applied immunology》1976,51(2):245-252
An increased frequency of antibodies to native DNA, thymocytes, and striated muscle was found in patients with myasthenia gravis (MG). The prevalence of such antibodies lends considerable support to the concept of MG as an autoimmune disorder and militates in favor of major abnormalities in the thymic dependent immune system. There was no correlation between serum-blocking activity to acetylcholine receptor protein and antibodies to thymocytes. 相似文献
110.