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831.
Analysis of IgH and TcR-γ genes using consensus primers identifying junctional regions of rearranged genes by polymerase chain reaction (PCR) was performed on tissues involved by Hodgkin's disease (HD) in 90 cases and was correlated with the immunophenotype of Hodgkin and Reed–Sternberg (HRS) cells and the presence of Epstein–Barr virus (EBV) within these cells. Clonal IgH gene rearrangements were found in 1/5 cases of lymphocyte predominance (LP) subtype and none was positive for EBV. In 85 cases of classic HD, no IgH or TcR-γ gene rearrangements were found in 51 (60 per cent) cases. A similar percentage, but not the same cases, were of null (non-B, non-T) phenotype. Of 30 cases where a B phenotype was assigned to HRS cells, nine had IgH gene rearrangements, three had TcR-γ gene rearrangements, and two had both genes rearranged. None of the five cases assigned to T phenotype of HRS cells showed rearrangement of TcR-γ genes, but two cases showed rearranged IgH genes. Among 41 cases of null phenotype, ten had IgH gene rearrangements, five had TcR-γ gene rearrangements, and three cases had both genes rearranged. Whereas EBV was detectable in HRS cells in 17/43 classic HD cases of assigned B phenotype, EBV was also detectable in 2/5 cases of assigned T phenotype and in 21 cases with the null phenotype. Furthermore, there was no correlation of EBV with the presence or lack of IgH or TCR-γ gene rearrangements. Of the remainder, half (30 per cent) expressed antigens associated with lymphocytes without an appropriate genotype. The results confirm lymphocyte-lineage committed cells at the origin of HRS cells in 40 per cent of cases. Any hypothesis of a non-lymphocytic origin of HRS cells will require the inducibility of CD30 on candidate precursors and the methodology for probing genetic events in such cells to be addressed. © 1997 by John Wiley & Sons, Ltd.  相似文献   
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Due to the COVID-19 infection, which was recognized as a global pandemic by the WHO on March 11, 2020, the number of cases and disease-related deaths increases day by day globally. For this reason, antiviral agents used in treatment and vaccines, the most effective weapon in prevention, continue to be the most popular topic of the plan. Several situations are expected to affect the course of the pandemic. The loss of the ability of the virus to mutate and cause disease, the fact that those who become immunized by having the disease in the society reach a critical rate and create social immunity (herd immunity), and the provision of social immunity with effective vaccination can be counted as some of these situations.Candidate vaccines in the clinical phase among RNA-based vaccines: This review aimed to examine COVID-19 vaccine candidates using RNA technology and compile its current data. We used PubMed, Google Scholar, and World Health Organization (WHO) databases. Also, we followed up on the latest news and developments on vaccine companies’ websites.Conclusion: Vaccination trials, which started due to the seriousness and urgency of the situation that we are in, continue exceptionally quickly and effectively. As per the WHO›s data on July 9, 2021, there have been 291 vaccine trials, 107 of which are in the clinical phase, and 18 (16%) of the vaccine candidates in the clinical phase are RNA-based vaccines. Also, the number of RNA-based vaccines with ongoing preclinical trials is 2  相似文献   
834.
OBJECTIVE: To investigate the neuropsychological characteristics of patients diagnosed with mild cognitive impairment (MCI) with and without apathy. METHODS: A cohort of 245 MCI patients (mean age = 72 +/- 5.5 years; mean MMSE = 27.5 +/- 1.3) was divided into two subgroups according to their Apathy Inventory score and underwent an extensive neuropsychological battery. RESULTS: There were 94 (38.4%) patients with and 151 (61.6%) patients without apathy. At baseline the apathetic subgroup had a significantly lower total score on the free and cued selective reminding test (FCSR). Furthermore, the apathetic subgroup showed a significant deterioration in FCSR total recall score between baseline and the 1-year assessment. In conclusion, the presence of apathy in MCI patients is not associated with frontal task performance but with a higher degree of memory impairment.  相似文献   
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Computed tomography in sciatica   总被引:6,自引:0,他引:6  
Carrera  GF; Williams  AL; Haughton  VM 《Radiology》1980,137(2):433-437
Lumber facet arthropathy and a herniated disk are two major causes of low back pain and sciatica. The authors evaluated the importance of computed tomography (CT) in 243 patients with low back pain and/or sciatica. Lumbar facet abnormalities were found in 139 patients (57%), and a herniated disk was found in 48 patients (20%). CT findings correlated precisely with surgical observations in cases involving a herniated disk and correlated well with the results of an intra-articular facet block in a small series of patients. CT can effectively diagnose and differentiate between lumbar facet arthropathy and a herniated disk.  相似文献   
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