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21.
Ras p21 expression in 30 cases of nephroblastoma and related tumors was evaluated by the immunoperoxidase method using monoclonal anti- ras p21 antibody (RAP-5) raised against a synthetic polypeptide fragment of ras p21. In normal renal tissue, the epithelial cells of convoluted and collecting tubules and arterial wall leiomyocytes were positively stained. In nephroblastoma tumors, some of the epithelial cells forming primitive tubular and glomerular-like structures in the nephroblastic-type tumors and the cells with including intimal features were positive. However, the epithelial cells in more differentiated glandular structures of epithelial-type tumors, the rhabdoid cells in rhabdoid tumors and the cells in congenital mesoblastic nephroma failed to show positive staining. Nephroblastic cells, stromal cells and sarcomatous cells were also negative.  相似文献   
22.
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was  相似文献   
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24.
A wide variety of influenza A viruses, comprising human, equine, porcine, and avian strains, grew productively in an established line of canine kidney cells (MDCK) under an overlay medium containing trypsin, and formed well-defined plaques regardless of their prior passage history. Plaquing efficiency was comparable to the efficiency of infection in fertile eggs via allantoic route. MDCK cells have also been successfully employed for the primary isolation of influenza A virus from throat washings of patients. Parallel titration of several clinical specimens showed that the inoculation into MDCK cells followed by incubation in the presence of trypsin was an isolation procedure as sensitive as the amniotic inoculation into fertile eggs.  相似文献   
25.
We generated transgenic mice expressing osteopontin (OPN) under the control of the alpha(1)-antitrypsin promoter. These mice (OPN-T mice) expressed OPN mRNA in liver and kidney, and released a large amount of plasma OPN, which increased after stimulation with turpentine oil. Before sensitization, the number of CD4+ T cells in lymph nodes was significantly higher in OPN-T than nontransgenic mice, and that in spleen was slightly higher, whereas that of CD8+ T cells was no different between OPN-T and nontransgenic mice. After sensitization, the CD4+ T cell numbers in spleen increased significantly, while there were almost no changes in the CD8+ T cells in lymph nodes and spleen. The intensity of contact hypersensitivity responses to 2,4-dinitrofluorobenzene (DNFB) was obviously enhanced in OPN-T mice. In the delayed-type hypersensitivity (DTH) model elicited by DNFB, the number of CD8+ T cells among DNFB-2,4,6-trinitrobenzenesulfonic acid (TNBS)-peritoneal exudate cells was significantly higher in OPN-T than nontransgenic mice, while there was almost no difference in that of CD4+ T cells. Adoptive transfer experiments revealed that the enhanced reactivity is carried by CD4+ and CD8+ T cells, respectively, although the ability of transferring DTH was significantly lower in CD8+ than in CD4+ T cells. The enhancement of CD8+ T cell migration was observed in OPN-T mice. These results suggest that OPN induces a proliferation of effector CD4+ and CD8+ cells in cell-mediated reactions and plays a role in the migration of CD8+ T cells.  相似文献   
26.
The secretion of tumor necrosis factor (TNF)-α from macrophages is regulated by both priming and triggering signals. We found that macrophages from mice lacking γδ T cells [T cell receptor (TCR) δ?/- mice], which lack the gene encoding the δ chain, produced only small amounts of TNF-α in response to lipopolysaccharide (LPS) and showed a reduced level of expression of CD14. Pre-incubation of macrophages from TCR δ-/- mice with γδ T cells from their TCR δ+/- littermates restored their capacity to produce TNF-α in response to LPS. The priming activity of γδ T cells was in part inhibited by neutralizing anti-interferon (IFN)-γ monoclonal antibodies. Collectively, these results suggest that γδ T cells play a role in priming macrophages to a steady state of activation via IFN-γ secretion, which allows them to produce TNF-α when exposed to LPS.  相似文献   
27.
The lower limits of the "therapeutic range" for serum levels of sodium valproate (VPA) were evaluated in epileptic children showing a benign clinical course. Twenty-five outpatients, aged 5 to 16 years, whose seizures were well controlled over three years with VPA alone, were studied. Venous blood was taken 1.1 to 5 hrs after the morning dose. Serum VPA concentrations at steady-state after receiving the maintenance doses to control seizures were determined by enzyme immunoassay. The patients were divided into three groups according to the seizure type and the age at onset; A and B: patients with tonic and/or clonic seizures, aged below 3 yrs (n = 11) and 3 to 11 yrs (n = 6), respectively, C: those with absence seizures, aged 4 to 11 yrs (n = 8). The serum concentrations in A (47.8 +/- 21.6 micrograms/ml, mean +/- SD) were significantly (p less than 0.02) lower than those in groups B and C (85.2 +/- 14.0 and 73.0 +/- 17.4 micrograms/ml, respectively). VPA concentrations below 50 micrograms/ml were seen in 6 patients (55%) in group A. It was concluded that many epileptic children, whose ages at onset were below 3 yrs, with tonic and/or clonic seizures could be controlled even with low initial serum concentrations below the "therapeutic range".  相似文献   
28.
Bevacizumab (BEV) is a key anti-angiogenic agent used in the treatment for recurrent glioblastoma multiforme (GBM). The aim of this study was to investigate whether cytoreductive surgery prior to treatment with BEV contributes to prolongation of survival for patients with recurrent GBM. We retrospectively analyzed the treatment outcomes of 124 patients with recurrent GBM who were initially treated with the Stupp protocol between 2006 and 2019. Given that BEV has only been available in Japan since 2013, we grouped the patients into two groups according to the time of first recurrence: the pre-BEV group (N = 51) included patients who had recurrence before BEV approval, and the BEV group (N = 73) included patients with recurrence after BEV approval. The overall survival after first recurrence (OS-R) was analyzed according to the treatment strategy. Among 124 patients, 27 patients (19.4%) received cytoreductive surgery. There were nine cases in the pre-BEV group and 18 cases in the BEV group. Although the mean extent of resection for both groups was almost equal, OS-R was significantly different. The median OS-R was 8.1 m in the pre-BEV group and 16.3 m in the BEV group (P = 0.007). Multivariate analysis revealed that the unavailability of BEV postoperatively (P = 0.03) and decreasing performance status by surgery (P = 0.01) were significant poor prognostic factors for survival after surgery. With the advent of BEV, cytoreductive surgery might provide superior survival benefit at the time of GBM recurrence, especially in cases where surgery can be performed without deteriorating the patient’s condition.  相似文献   
29.
BackgroundPerforming total hip arthroplasty (THA) as early as possible is recommended for rapidly destructive coxarthrosis (RDC) as it causes pain that becomes progressively more severe. However, acetabular bone loss remains an issue in THA. Special devices, such as a Kerboull-type plate, may be used for acetabular bone defects, but the procedure is highly invasive and often the patients are elderly, further complicating matters. We retrospectively investigated the clinical and radiographic results of THA using conventional hydroxyapatite-coated cementless cup in RDC.MethodsA total of 32 patients (35 hips) with RDC were enrolled in the study with a minimum 10-year follow-up. All THAs were performed using conventional hydroxyapatite-coated cementless cup. All patients were evaluated clinically according to the Harris hip score (HHS). Acetabular bone deficiency was classified according to the American Academy of Orthopaedic Surgeons (AAOS) classification.ResultsEleven hips (31%) were AAOS type III, and none were type IV. Total HHS significantly improved from 36.5 to 79.4 (p < 0.01). Two cups exhibited loosening. The overall implant-associated survival rate after 10 years was 91.4%.ConclusionsClinical results of THA using conventional cementless implants for patients with RDC were acceptable. Thus, THA using conventional cementless implant is an effective and safe surgery for patients with RDC, minimizing surgical stress.  相似文献   
30.
BackgroundTranstendinous rotator cuff tear is likely to occur due to trauma in sports activities, with a frequency of <2% of total rotator cuff tears. These tears are difficult to treat because of limited tendon tissue in the proximal stump, and standard repair techniques are sometimes ineffective. Few studies have reported on the repair technique and clinical outcomes for transtendinous rotator cuff tear, and an appropriate repair technique has, therefore, not been established. The purpose of this study was to use our modified load sharing rip-stop technique to repair transtendinous rotator cuff tear and to clarify the clinical effectiveness of this technique.MethodsThis was a retrospective case series review of eight patients who underwent the modified load sharing rip-stop technique for repairing traumatic transtendinous rotator cuff tear between January 2013 and June 2017. The eight patients were followed up for at least 2 years (range: 24–41 months). Cuff integrity was evaluated using magnetic resonance imaging at 12 months after surgery using the Sugaya classification. We evaluated the pre- and postoperative ranges of motion, American Shoulder and Elbow Surgeons score, Constant Shoulder Score, and muscle strength at 90° abduction. Data were analyzed using the Mann–Whitney U test and Fisher's exact tests. P < .05 was considered to indicate statistical significance.ResultsSix patients were classified as Sugaya I and two as Sugaya II. ASES score (38.5–90.2, P = .0008), Constant shoulder score (36.5–79, P = .002), flexion (85°–158.1°, P = .002), abduction (85°–157.5°, P = .001), external rotation (38.8°–55°, P = .024), and muscle strength at 90° abduction (2.95–5.39 kg, P = .028) improved significantly. Six patients were able to return to their previous sports activity.ConclusionUsing our modified load sharing rip-stop technique for repair of transtendinous rotator cuff tear, patients obtained good clinical outcomes and could return to sports activities.  相似文献   
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