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51.
Lymphocytes obtained from cord blood of newborn babies who were born of healthy mothers were studied in vitro for their responsiveness to purified protein derivative (PPD) of tuberculin. Cord blood lymphocytes proliferated in vitro by stimulation with PPD, despite wide variations in the results. Studies with fractionated lymphocytes revealed that PPD-responding cells belonged to E-rosetting, nylon wool-nonadherent T lymphocytes. Non-E-rosetting B lymphocytes alone did not proliferate at all after stimulation with PPD. In addition, bromodeoxyuridine and light treatment of in vitro PPD-stimulated lymphocytes eliminated the responsiveness to PPD. These results suggest that T lymphocytes do exist in cord blood and respond in vitro to stimulation with PPD. A possible role for PPD-reactive T lymphocytes in cell-mediated protective immunity in newborns is discussed.  相似文献   
52.
In vitro lymphocyte proliferative response to purified protein derivative of tuberculin (PPD) was investigated in patients with tuberculosis. Peripheral blood lymphocytes (PBL) from patients with advanced, refractory tuberculosis showed a significantly depressed response compared with the response of PBL from patients with newly diagnosed tuberculosis (P less than 0.01). A further characterization of this low responsiveness to PPD revealed that PBL from these advanced tuberculous patients failed to generate interleukin-2 (IL-2) in response to PPD stimulation. IL-2 receptor (Tac antigen) expression on the surface of T cells after PPD stimulation was also impaired, although to a lesser extent, in the patients with advanced, refractory tuberculosis. We attempted to overcome the depressed in vitro response observed in PBL from patients with advanced, refractory tuberculosis and found that the addition of exogenous, recombinant IL-2 returned the depressed PPD-induced PBL proliferation in these patients to the level of response observed in PBL from patients with newly diagnosed tuberculosis. The addition of recombinant IL-2 also had a restorative effect (up regulation) in vitro on the partly impaired PPD-induced IL-2 receptor expression by PBL from the patients with advanced, refractory tuberculosis. Our results suggest that recombinant IL-2 may offer a novel approach to the therapy of advanced, drug-resistant tuberculosis.  相似文献   
53.
The presence of rhabdoid cells has been reported in various types of malignant neoplasms and has been determined to be a predictor of aggressive behavior of neoplasms regardless of tumor histogenesis. One hundred and thirteen cases of leiomyosarcoma, selected from 1800 soft tissue sarcomas, were reviewed on hematoxylin and eosin sections, and immunohistochemical staining when available, and seven cases with rhabdoid features were retrieved. Clinicopathologic differences were analyzed to compare between cases with rhabdoid features and those without rhabdoid features. In the seven cases with rhabdoid features, two were intra-abdominal, and the others arose in external soft tissues including muscle, subcutis, and cutis. Patient age ranged from 33 to 84 years, three were female, and four were male. Tumor size ranged from 3 to 22 cm. Clinical evidence showed no differences from those cases without rhabdoid features. Histologically, one of the abdominal cases was epithelioid leiomyosarcoma. Two of the 7 cases were better subclassified as pleomorphic leiomyosarcoma, in which rhabdoid cells are diffusely scattered. In cases other than those with pleomorphic leiomyosarcomas, foci of anaplastic areas were observed, and collections of rhabdoid cells were present in those areas. Immunohistochemical examination of the cases confirmed myogenic differentiation, and showed rhabdoid cells being positive for vimentin and desmin in the inclusion bodies, and diffusely so for muscle actin in the cytoplasm. After dividing all the cases of leiomyosarcoma by their location, prognostic analysis was performed. Leiomyosarcoma of external soft tissue with rhabdoid cells showed a tendency for poorer prognoses than cases without rhabdoid features. On the contrary, retroperitoneal cases did not. This study indicates that rhabdoid features are associated with aggressive biological behavior in leiomyosarcoma of the external soft tissue.  相似文献   
54.
BACKGROUND: Depressive (or depression-like) episodes are the most common manifestations of bipolar affective disorder in early teenage years. The present paper analyses the clinical features and their changes over time in these episodes. METHODS: By a prospective study on children who had their first affective or psychotic episodes between the ages of ten and fifteen, those who eventually met the ICD 10 diagnostic criteria for bipolar disorder were selected and followed up. RESULTS: There were three boys and nine girls. Their early depressive episodes were characterised by psychotic features and clinging to the mother in most cases, and in some by brief episodes and/or a good response to sulpiride. However, these characteristics tended to disappear with increasing age. Five children (42%) had an IQ of 61-75. LIMITATIONS: Generalisability of the results is limited because of the small number of patients and the lack of control groups. CONCLUSIONS: Bipolar disorder in early teenage years may show clinical features and a drug response that are different from those in adulthood. Low IQ may expedite the onset of bipolar disorder.  相似文献   
55.
Infection with a variety of viruses induces apoptosis in host cells. This phenomenon may be considered to be a self-defense mechanism to avoid viral propagation. However, the growth of influenza virus is completed before host cells become dysfunctional due to apoptosis. To clarify the physiologic consequences of influenza virus-induced apoptosis, the fate of influenza virus-infected cells was examined in vitro as well as in vivo. Influenza virus-infected cells were engulfed by macrophages in vitro, and virus propagation was almost completely inhibited. This phagocytosis was dependent on the specific recognition of the membrane phospholipid phosphatidylserine exposed on the surface of virus-infected apoptotic cells by macrophages. In addition, the activity of viral neuraminidase expressed at the surface of virus-infected cells was necessary for the maximal level of phagocytosis. When mice infected with influenza virus were administered phagocytosis inhibitors, the level of lethality and inflammation in the lung were augmented. These results show that apoptosis makes influenza virus-infected cells susceptible to phagocytosis by macrophages, and that this leads to a reduction in the extent of influenza pathology.  相似文献   
56.
Resection of bilateral pheochromocytomas of a 33-year-old man with Sipple syndrome was scheduled. Oral prazosin was started twenty days before the operation and increased to a maintenance dose of 6 mg per day. Oral lavetalol 300 mg per day was added for five days before the operation because prazosin alone was insufficient. Intravascular volume was expanded with two units of stored whole blood per day for four days before the operation for preoperative preparation. Anesthesia was induced with thiamylal 250 mg and vecuronium bromide 9 mg, and maintained with enflurane, nitrous oxide and oxygen. Phentolamine, labetalol and nitroglycerin were used for treatment of hypertensive crises during operation and anesthesia. To combat hypotension which follows the resection of the tumor, continuous infusion of norepinephrine was used for four hours after the operation. There were no hypotensive periods and no complications. After removing bilateral pheochromocytomas of the adrenals, treatment of full adrenocortical replacement therapy was performed. Concurrent use of alpha-and beta-adrenergic blocking agents was important for successful anesthetic management for the resection of pheochromocytoma.  相似文献   
57.
Immunohistochemical evaluation of PCNA and Ki-67 in ameloblastoma   总被引:1,自引:0,他引:1  
Thirty-two ameloblastoma tissues were immunohistochemically studied using monoclonal anti-proliferating cell nuclear antigen (PCNA) and anti-Ki-67 antibodies. Positive cells were evaluated and analyzed in relation to the WHO classification, cytological pattern of the outer layer cell, clinical appearance, tumor location, radiographic appearance and patient's age. In regard to the cytological pattern of the outer layer cells, the basal cell type had significantly higher PCNA and Ki-67 (P<0.05) labeling indices than the cuboidal cell type. The solid type had significantly higher PCNA and Ki-67 (P<0.05) labeling indices than the cystic and the mixed type. The labeling index of the younger patient was found to be the lowest, the middle age was in the middle and the older patient was the highest. These results indicated that the proliferating activities of ameloblastomas are quite variable, and the evaluations of Ki-67 and PCNA seem to be good indicators to assess the proliferating activity of each type of ameloblastomas.  相似文献   
58.
A case of sarcoidosis involving the tongue is described in a 48-year-old Japanese man. A definite diagnosis of sarcoidosis was made for the clinical lesion and pathological examinations. Sarcoidosis is a multisystem granulomatous disease that may affect any organ. Sarcoidosis of the tongue is particularly rare.  相似文献   
59.
The effect of potassium loading on plasma adrenocortical hormones concentrations in 9 patients with essential hypertension (EH) was investigated. The plasma renin activity (PRA), plasma concentrations of growth hormone (GH), ACTH, cortisol, deoxycorticosterone (DOC), 18-hydroxy-deoxycorticosterone (18-OH-DOC) and aldosterone, and serum electrolytes were measured before and after potassium chloride (KC1) infusion (0.33 mEq/kg/h, for one hour). The KC1 infusion caused significant increases in serum potassium levels and plasma levels of GH, ACTH, cortisol, DOC, 18-OH-DOC and aldosterone, while PRA remained unchanged. Regression analysis at 30 min revealed significant positive correlations between delta ACTH and delta cortisol, between delta ACTH and delta DOC, between delta ACTH and delta 18-OH-DOC. However, the relationship between delta ACTH and delta aldosterone was not statistically significant. These results suggest that (1) acute potassium loading causes a significant increase in the plasma ACTH level and increased levels of adrenocortical hormones may be produced by increased ACTH secretion, and (2) it may be considered that a part of the increased level of plasma aldosterone following acute potassium loading may arise from increased ACTH secretion in EH.  相似文献   
60.
A 68-year-old woman was admitted to our hospital with xerophthalmia, xerostomia, leukopenia, and thrombocytopenia. She was diagnosed to have SjÖgrens syndrome and autoimmune cytopenia. After 11 months, she was readmitted with severe anemia and reticulocytopenia. Mild hemolysis was seen, and bone marrow aspirate showed markedly decreased erythropoiesis. An association of pure red cell aplasia (PRCA) and autoimmune hemolytic anemia was diagnosed. After treatment with cyclosporine and prednisolone, her anemia dramatically improved. We discuss the mechanism of PRCA associated with SjÖgrens syndrome.  相似文献   
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