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51.
A case of multiple myeloma diagnosed by fine-needle aspiration (FNA) biopsy and confirmed by laboratory studies in a patient with a history of renal-cell carcinoma is presented. The patient was diagnosed with renal-cell carcinoma of the right kidney and a radical nephrectomy was performed. Eighteen months after this diagnosis was made, the patient developed chest wall pain and was found to have osteolytic bone lesions of the ribs and vertebral bodies. FNA of an osteolytic rib lesion disclosed multiple myeloma. Additional laboratory studies confirmed the diagnosis of multiple myeloma. This case report demonstrates the value of FNA as a diagnostic tool for the follow-up of cancer patients, the subsequent discrimination between metatastic lesions and a second primary malignancy, and the cytology of multiple myeloma.  相似文献   
52.
本文采用部分肋骨切除术,切除15只家兔双侧5、6、7、8肋中任一肋距脊柱约2cm处一段长约1cm的肋骨。一周后对受冲击波致伤的肺肋面的出血情况进行解剖观察,发现肺肋面的出血条纹呈“工”字形,从而为冲击伤肺肋面的平行出血条纹是肋间压痕这一观点找到了直接的实验证据。  相似文献   
53.
Radiation exposure is an occupational hazard for military personnel, some health care professionals, airport security screeners, and medical patients, with some individuals at risk for acute, high-dose exposures. Therefore, the biological effects of radiation, especially the potential for chromosome damage, are major occupational and health concerns. However, the biophysical mechanisms of chromosome instability subsequent to radiation-induced DNA damage are poorly understood. It is clear that interphase chromosomes occupy discrete structural and functional subnuclear domains, termed chromosome territories (CT), which may be organized into ‘neighborhoods’ comprising groups of specific CTs. We directly evaluated the relationship between chromosome positioning, neighborhood composition, and translocation partner choice in primary lymphocytes, using a cell-based system in which we could induce multiple, concentrated DNA breaks via high-dose irradiation. We critically evaluated mis-rejoining profiles and tested whether breaks occurring nearby were more likely to fuse than breaks occurring at a distance. We show that CT neighborhoods comprise heterologous chromosomes, within which inter-CT distances directly relate to translocation partner choice. These findings demonstrate that interphase chromosome arrangement is a principal factor in genomic instability outcomes in primary lymphocytes, providing a structural context for understanding the biological effects of radiation exposure, and the molecular etiology of tumor-specific translocation patterns.  相似文献   
54.
Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77-year-old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term 'hemangiosarcoma/anglosarcoma', 'hemangioendothelloma/endothelloma' or 'vascular sarcoma' of the kidney were reviewed and compared to the present case.  相似文献   
55.
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients.  相似文献   
56.
cDNA clones corresponding to the mRNA for the hemagglutinin of the hemagglutination-defective strain AK-1 of measles virus were isolated and characterized. Compared with the prototype Edmonstron strain, 60 nucleotide substitutions that resulted in 18 amino acid changes were detected. An additional potential N-linked glycosylation site was added by point mutation, which was supported by the observation that the hemagglutinin of the AK-1 strain was stained more heavily after NaDodSO4PAGE and periodic acid-Schiff (PAS) staining than the Edmonston strain. Computer-assisted analysis revealed that three reverse turns in the secondary structure had disappeared in the hemagglutinin of the AK-1 strain. Moreover, one of these structural changes occurred in the closely glycosylated region at amino acid residues 168–240, which appeared to be a biologically important functional domain. The isoelectric point calculated from the predicted amino acid sequence became about 1 pH unit more basic in the AK-1 strain than the Edmonston strain. This present study is the first sequence analysis of the hemagglutinin gene in a hemagglutination-defective strain of the measles virus.  相似文献   
57.
BACKGROUND: Cervical mucus is a heterogeneous mixture of water, ions and mucins that form a hydrophilic polymer gel. Mucins, the main components of mucus, are condensed inside secretory granules and swell to become a hydrogel after exocytosis. Using human cervical secretory cell primary cultures, the effect of [Ca(2+)] and [H(+)] on the swelling velocity of mucin granules was investigated in vitro. METHODS and RESULTS: Immunocytochemistry demonstrated that estrogen and progesterone receptors were expressed in cultured secretory cells along with mucins type 1, 4, 5AC and 5B. Exocytosis of secretory cells, recorded by videomicroscopy, showed that during swelling, the radius of the secretory granule matrix followed first-order kinetics. An increase in extracellular [Ca(2+)] from 1 to 4 mmol/l or a reduction in pH from 7.4 to 6.5 was seen to produce a significant decrease in the velocity of swelling of the secretory granule matrix. CONCLUSIONS: The inverse relationship observed between the diffusion of the granular matrix and the extracellular [Ca(2+)] or [H(+)] suggested that changes in cation concentration might drastically affect the swelling characteristics of mucins and provide a control mechanism for the observed viscoelastic properties of mucus.  相似文献   
58.
To clarify the role of IP-10 in autoimmune liver diseases, we studied the serum levels of IP-10 in 14 patients with autoimmune hepatitis (AIH), 23 patients with primary biliary cirrhosis (PBC), and 65 patients with chronic viral hepatitis (20 type B and 45 type C). The hepatic expression of IP-10 mRNA and the correlation between the serum levels of IP-10 and clinical parameters were also evaluated. In addition to 20 healthy controls, 16 rheumatoid arthritis (RA) patients were included as an extrahepatic inflammatory disease. The serum level of IP-10 was significantly (P < 0.02) higher in patients with AIH, PBC, and chronic hepatitis B and C than in healthy controls, and it was significantly correlated (P < 0.05) with the serum levels of aspartate aminotransferase and alanine aminotransferase in patients with AIH, PBC, and chronic hepatitis B and C. The serum level of IP-10 was not elevated in RA patients. After successful treatment of AIH and chronic hepatitis C, the serum level of IP-10 decreased to the same level as in healthy volunteers. As we previously showed in cases with chronic hepatitis B or C, in situ hybridization in both AIH and PBC cases demonstrated the expression of IP-10 mRNA in hepatocytes around focal or lobular necrosis surrounded by infiltrating mononuclear cells, whereas IP-10 mRNA was not expressed in areas around the damaged bile ducts in PBC cases. The present results suggest that IP-10 is specifically produced by hepatocytes in inflammatory areas irrespective of the aetiology of hepatitis, and that IP-10 may help to recruit T cells to the hepatic lesions in autoimmune liver diseases as well as in chronic viral hepatitis.  相似文献   
59.
Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established.  相似文献   
60.
Targeted recombination was carried out to select mouse hepatitis viruses (MHVs) in a defined genetic background, containing an MHV-JHM spike gene encoding either three heptad repeat 1 (HR1) substitutions (Q1067H, Q1094H, and L1114R) or L1114R alone. The recombinant virus, which expresses spike with the three substitutions, was nonfusogenic at neutral pH. Its replication was significantly inhibited by lysosomotropic agents, and it was highly neuroattenuated in vivo. In contrast, the recombinant expressing spike with L1114R alone mediated cell-to-cell fusion at neutral pH and replicated efficiently despite the presence of lysosomotropic agents; however, it still caused only subclinical morbidity and no mortality in animals. Thus, both recombinant viruses were highly attenuated and expressed viral antigen which was restricted to the olfactory bulbs and was markedly absent from other regions of the brains at 5 days postinfection. These data demonstrate that amino acid substitutions, in particular L1114R, within HR1 of the JHM spike reduced the ability of MHV to spread in the central nervous system. Furthermore, the requirements for low pH for fusion and viral entry are not prerequisites for the highly attenuated phenotype.  相似文献   
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