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21.
A case of melanocytic schwannoma, a rare form of schwannian neoplasm, in the thoracolumbar spinal canal of a 52-year-old man is presented. Histopathologically, the tumor was composed of irregularly interlacing spindle-shaped cells showing cystic degeneration, with occasional pigmented tumor cells. The tumor cells showed a low degree of nuclear pleomorphism without any mitotic figures. These histological features were considered to be consistent with a benign schwannian tumor showing pigmentation. Most of the pigments were considered to be melanin histochemically and immunohistochemically. According to the pathological features of the present tumor and those described previously in the literature, the neoplastic Schwann cells were assumed to have melanogenetic capacity, and the concept of the common neural crest origin of Schwann cells and melanocytes appeared to be demonstrated in the present tumor.  相似文献   
22.
A 56-year-old Japanese man with a malignant lymphoma of the parotid gland was reported. The tumor was located in the superficial lobe of the parotid gland, and somewhat invaded the surrounding soft tissues, but the regional lymph nodes were not involved. Histologically, the tumor was composed of round cells with plasmacytoid configurations and small lymphocytes. The plasmacytoid cells showed eccentric nuclei with fairly marked irregularities and perinuclearr halos. In a large number of tumor cells, a monoclonal cytoplasmic immunoglobulin (CIg), IgG-Kappa type, was demonstrated by the PAP method. Ultrastructurally, some of the tumor cells showed well-developed endoplasmic reticulum. From these findings, this tumor was diagnosed as a diffuse B-cell lymphoma, mainly composed of lymphoplasmacytoid cells. And this tumor may bear a similar nature to an extramedullary plasmacytoma of the classical terminology. Malignant lymphoma of the parotid gland is rare but a case with the demonstration of monoclonal CIg is considered very rare.  相似文献   
23.
M Hossain  Y Okubo  S Horie    M Sekiguchi 《Immunology》1996,88(2):301-307
We examined the hypothesis that one of the pro-inflammatory cytokines, tumour necrosis factor-alpha (TNF-alpha), could induce expression of the adhesion molecule CD4 on human eosinophils. We further examined the effector function of CD4 and the mechanisms regulating CD4 expression. Human eosinophils were cultured with various concentrations of recombinant human TNF-alpha (rhTNF-alpha) with or without various drugs for 24 hr. After culture, eosinophils were stained for CD4 using a monoclonal antibody and then analysed by flow cytometry. Eosinophil-derived neurotoxin (EDN) release as eosinophil degranulation was examined by cross-linking of CD4 on eosinophils. The rhTNF-alpha induced CD4 expression on human eosinophils in a dose- and time-dependent fashion; rhTNF-alpha-induced CD4 expression was significantly inhibited by 10(-6) M cycloheximide, 10(-8) M dexamethasone, or 10(-6) M herbimycin A. Recombinant human interferon-gamma inhibited rhTNF-alpha-induced CD4 expression in a dose-dependent manner. However, cross-linking of CD4 on eosinophils did not evoke EDN release, suggesting that newly expressed CD4 molecules on human eosinophils do not play any role in triggering degranulation. Our data indicate that TNF-alpha-induced CD4 expression on human eosinophils is dependent on protein synthesis and may be dependent on tyrosine kinase activity.  相似文献   
24.
25.
通过运用仿真人体模型对松果体区靶病灶直线加速器多聚弧照射的监测,论证直线加速器作为放射外科工具治疗颅内病变的科学性,探讨有关辐射参数对剂量分布的影响。作者认为,直线器放射外科可实现与伽玛马相似的剂量分布,同是神经外科安全有效的治疗技术,准直器孔径越小,照射范围越大,则剂量梯度即越大,剂量分布越理想;靶区最大剂量对上器孔径有相当高的依赖性,本文还就合理的照射弧范围及边缘处方剂量作了讨论。  相似文献   
26.
A 16-year-old patient with multiple sclerosis (MS) showed paroxysmal movement disorders during a recurrence of the disease. The paroxysms took the form ot brief unilateral dystonic posturings of the right body suggestive of paroxysmal dystonia (PD); they completely receded with acetazolamide. A single episode of a high amplitude, rythmic slow and coarse generalized tremor, present at rest and increasing with movement, particularly involving the head in a no-no movement, occurred soon after recovery from PD and lasted three hours. The present report provides evidence that MS has to be considered in the diagnostic approach to symptomatic childhood PD and underlines the efficacy of acetazolamide in the treatment of PD attacks. It also describes a rare paroxysmal movement disorder, defined as paroxysmal dystonic tremor, that can be considered as falling within the spectrum of PD.This study was partially supported by the Paolo Zorzi Association for Neurosciences, and the Harry De Jur Foundation.  相似文献   
27.
Hepatic vitronectin expression was assessed in 27 patients with chronic hepatitis C before and after interferon alpha treatment and in 7 control patients. Before interferon therapy, vitronectin was localized in the hepatocytes and in the portal and central venous regions. A high correlation was found for the vitronectin expression level with the histological grading and staging scores in the hepatocytes as well as in the portal region. After interferon therapy, the hepatic vitronectin was significantly decreased in the sustained and transient responders, but it was not as markedly decreased in the nonresponders and the non-treated group. A good correlation was found for the vitronectin expression with the staging scores but not with the grading scores in the portal region. These findings suggest that hepatic vitronectin is influenced by interferon therapy and that it may play an important role as a hepatic adhesion molecule through the improvement of inflammation, necrosis and fibrogenesis.  相似文献   
28.
Horie S  Tobisu KI  Fujimoto H  Doi N  Kakizoe T 《Urology》1999,53(3):561-567
OBJECTIVES: The impact of non-nerve-sparing retropubic radical prostatectomy (RRP) for prostate cancer combined with neoadjuvant androgen deprivation on urinary control is not well documented. We examined the incidence and severity of urinary incontinence after such therapy and determined the etiologic factors causing this complication. METHODS: We examined the postoperative continence status of 104 consecutive patients admitted to the National Cancer Center Hospital who underwent RRP with wide resection of the pelvic nerves after neoadjuvant androgen deprivation. Incontinence was scored according to the number of pads used daily by the patient for urinary leakage. The severity of incontinence was analyzed according to patient age, weight of resected specimen, status of cancer stage, duration of neoadjuvant androgen blockade therapy, preoperative length of membranous urethra, and duration of urethral catheterization after surgery. We also measured the configuration and diameter of the reconstructed bladder neck by retrograde cystourethrography. RESULTS: In 104 patients examined, the percentage of patients who became dry postoperatively was 22% at 1 month, 47% at 3 months, 69% at 6 months, and 78% at 1 year. Of 81 patients who became dry postoperatively at any interval, 22 (27%) became continent within 1 month of RRP, 49 (61 %) were continent within 3 months, 71 (88%) became continent by 6 months, and another 10 (12%) became continent between 6 and 12 months postoperatively. Of 48 patients who were followed up for more than 1 year and for whom continence status at 1 month after surgery was available, all patients who used 1 to 2 pads per day (13 of 13) at 1 month after surgery regained continence by 1 year after surgery. However, only 62% of patients (16 of 26) who required more than 3 pads per day at 1 month after surgery became dry by 1 year after surgery. Only age (older than 70 years) and large prostate size (weight of surgical specimen more than 40 g) temporarily influenced the recovery of urinary continence after surgery. Dilation of the bladder neck evaluated by retrograde cystourethrography was prominent in severely incontinent patients in the immediate postoperative period. CONCLUSIONS: Our experience in patients who undergo non-nerve-sparing RRP after neoadjuvant androgen deprivation closely matches published surveys of patient-reported complications. Postoperative incontinence is not a major contraindication for non-nerve-sparing RRP after neoadjuvant endocrine therapy. Dilation of the bladder neck affected the recovery from incontinence, highlighting the importance of adequate reconstruction of the bladder neck.  相似文献   
29.
Local blood flow of the bowel wall was measured by hydrogen clearance method both in the muscular and submucosal layers in the mongrel dog, separately and concurrently. A platinum wire electrode with a bare tip of 0.5 mm in length and 0.2 mm in diameter was inserted into each layer. About 10 per cent hydrogen gas was inhalated directly through the side hole attached to the endotracheal tube for 1–2 minutes and the obtained clearance curves were plotted on the semi-logarithmic scale, which was almost monoexponential. The results obtained were as follows:
  1. Mean basal perfusion rate of the muscular layer of the intestine was 0.81–0.92 ml/min/gm, whereas that of the submucosal layer was 1.29–1.31 ml/min/gm, respectively. There was little difference of perfusion rates between the small and the large intestine. The results showed good correlationship with those reported by other authors.
  2. The effect of vasoactive substances such as vasoconstrictor and vasodilator on the local blood flow in the bowel wall was confirmed.
  3. This method is repeatedly applicable for measurement and also renders the information on the distribution of blood flow in the splanchnic area.
  相似文献   
30.
A 55-year-old female presented with a unique case of gliosarcoma with a huge cystic component manifesting as loss of consciousness, left-sided hemiparesis, and anisocoria. Computed tomography demonstrated a large cyst in the right frontal lobe, and enhancement of the mural nodule after administration of contrast medium. Emergent operation was performed. Xanthochromic fluid was aspirated, and the tumor was resected. The histological diagnosis was gliosarcoma based on the presence of gliomatous and sarcomatous components. She underwent a second operation because of tumor regrowth 3 weeks after the first operation. The postoperative course was satisfactory during radiation therapy with 60 Gy and chemotherapy. The diagnosis of gliosarcoma was difficult to make preoperatively because of the neuroradiological findings similar to low-grade gliomas. Gliosarcoma should be included in the differential diagnosis of huge cystic tumors.  相似文献   
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