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121.
122.
Ultraviolet irradiation enhanced the Candida albicans killing activity of freshly separated human epidermal cells in vitro. The stimulation was dose-dependent and was not due to soluble extracellular factors acting on non-irradiated epidermal cells. The enhancement of the killing activity remained unchanged when epidermal cells were depleted of Langerhans cells. Protein synthesis inhibitors and prostaglandin antagonists abrogated the ultraviolet-induced augmentation of killing activity.  相似文献   
123.
The aim of this study was to evaluate the performance of a molecular assay for quantitation of Epstein-Barr virus (EBV) DNA based on real-time PCR, and to determine EBV DNA levels in EDTA whole blood samples derived from different groups of patients. Following a manual DNA extraction protocol, real-time PCR was performed using the LightCycler EBV Quantification Kit, which demonstrated sufficient accuracy and linearity. Coefficients of variations were found to be between 6 and 42% and 5 and 34%, respectively, for inter-assay and intra-assay variations. In clinical specimens, EBV DNA was detected in all patients with acute EBV infection (n=34), in one of 25 adults with past EBV infection, in 16 out of 25 (64%) anti-HIV antibody positive persons, in 10 out of 25 (40%) solid organ transplant recipients, and in none of the 23 infants without history of EBV infection. When EBV DNA levels in positive specimens were compared between different groups, statistically significant differences were not found. The LightCycler EBV Quantification Kit was found to be useful for determination of EBV DNA levels in EDTA whole blood.  相似文献   
124.
Age-dependence of the spontaneous activity of the rat urinary bladder   总被引:2,自引:0,他引:2  
Abnormal mechanical function of the bladder is manifested in a number of ways including higher frequency of involuntary detrusor contractions associated with reduced compliance of the bladder that is responsible for an increase in intraluminal pressure during filling. There are basically two ways to approach experimentally these problems: (1) by studying the neural control of the lower urinary tract function, and (2) by measuring the properties of smooth muscle cells in the bladder wall. Studies on smooth muscle function often do not take the origin of smooth muscle cells into account i.e., whether they were harvested from normal or overactive bladders. Although, this simplistic view may be beneficial to understanding the generation of the spontaneous activity of the bladder, however, it does not sufficiently explain the cell-to-cell propagation of the spontaneous smooth muscle activity. The spontaneous activity of smooth muscle is an important factor that works against the bladder compliance in the filling phase, and may inversely affect the neurally evoked response during micturition. The intensity of spontaneous activity is the age-dependent; it is high in neonatal bladders it is small or almost non-existent in adults and reemerges in older bladders. This review focuses on these age-dependent alterations of spontaneous bladder contractions and describes the possible mechanisms which may have important role in regulating the spontaneous contractions using the rat as an animal model.  相似文献   
125.
Bacillary angiomatosis in a patient with lymphocytic leukaemia   总被引:1,自引:0,他引:1  
Summary A 78-year-old man, who suffered from chronic lymphocytic leukaemia and diabetes mellitus, but was human immunodeficiency virus (HIV)-negative, developed disseminated angiomatous papule's following a cat scratch. Bacillary angiomatosis was diagnosed by light and electron microscopic demonstration of the causative bacteria in the vascular lesions. The lesions resolved completely when he was treated with erythromycin. This case demonstrates that bacillary angiomatosis can be an important cutaneous manifestation of immunodeficiency in individuals who are not infected with the human immunodeficiency virus.  相似文献   
126.
Interferons (IFNs) are a group of cytokines exhibiting antiviral, antiproliferative and immunoregulatory properties. The principal stimulus for the synthesis of IFNs is the presence of viral double-stranded RNA, although rare examples of constitutive synthesis have also been described. The aim of the present study was to determine IFN-alpha-like biological activity in the seminal plasma, follicular and amniotic fluid, embryo culture medium, and fetal blood obtained from patients without apparent viral or bacterial infections. Interferon-alpha-like biological activity was determined by a standard cytopathic effect inhibition bioassay. The study included two groups of patients. The first group consisted of 30 married couples participating in the programme for assisted reproduction and the second group consisted of 23 patients scheduled for prenatal diagnosis (15 for amniocentesis and eight for cordocentesis). The seminal plasma of infertile men (asthenozoospermia, oligoasthenozoospermia) contained a high titre of IFN-alpha-like antiviral activity. Asthenozoospermia was diagnosed in men with a normal sperm concentration but less than 50% progressively motile sperm and oligoasthenozoospermia was diagnosed in men with a sperm count less than 1 x 10(6) mL(-1). Despite slightly higher antiviral titres in the seminal plasma obtained from asthenozoospermic patients, no clear association between IFN-alpha-like biological activity and sperm concentration was found. Interferon-alpha-like biological activity was found in all samples of follicular and amniotic fluid and in fetal blood of patients with intrauterine growth retardation and trisomy 18. Antiviral titres from seminal plasma and follicular fluids were significantly higher compared with amniotic fluids and fetal blood. Embryo culture medium did not contain IFN-alpha-like biological activity. Our results demonstrate that IFN-alpha-like activity in biological fluids is relevant for reproduction, even in the absence of infection.  相似文献   
127.
128.
Duodenal neoplasms: role of CT   总被引:5,自引:0,他引:5  
In a retrospective study of 14 cases of duodenal neoplasms evaluated by computed tomography (CT), there were four primary adenocarcinomas of the duodenum, one lymphoma, five metastatic carcinomas, two duodenal lipomas, one villous adenoma, and one leiomyoma. The CT findings were diagnostic in patients with duodenal lipomas. In 11 cases, a primary origin of the mass was clearly identifiable in the duodenum. Thickening of the bowel wall, tumor necrosis, ulceration, and intraluminal defects were common. The relationship of the masses to adjacent structures was clearly shown on CT scans. Extraluminal extent of the lesion was noted on CT scans in seven patients; however, at surgery only four of six were found to have extramural disease. The presence of adenopathy, liver metastases, and vascular and mesenteric invasion were also demonstrated on CT scans. Twelve patients underwent upper gastrointestinal tract series. A duodenal abnormality was seen in all 12 patients, but the extramural extent and distant metastatic involvement could not be seen on these examinations. CT scans allowed the accurate staging of eight of ten malignant lesions and thus helped in the management of duodenal tumors.  相似文献   
129.
姚守拙  肖俊  聂利华 《药学学报》1988,23(4):281-287
阳离子型脱氧土霉素电极在pH 1.5~3.5响应含质子化二甲胺基的脱氧土霉素一价阳离子。阴离子型脱氧土霉素电极在pH 8.0~10.5只响应含离解B环烯醇基的一价脱氧土霉素阴离子,但电位稳定性差。用全固态电极倒置法可测微体积样液中μg级盐酸脱氧土霉素。logKij与季铵离子势及诱导效应指数有良好的线性关系,极限值为7.48。周期系ⅠA及ⅡA族元素的logkij随Z/R减小而增大。  相似文献   
130.
Long-term suspension cultures of human cord blood myeloid cells   总被引:2,自引:0,他引:2  
Salahuddin  SZ; Markham  PD; Ruscetti  FW; Gallo  RC 《Blood》1981,58(5):931-938
A method is described that allows for the routine long-term (greater than 3 mo) growth of normal, immature human myeloid cells in liquid suspension culture. The techniques employ cell separation, utilization of special growth conditions (RPMI with hydrocortisone and vitamin D), and cord blood as the source of leukocytes. These cultures are composed predominantly of immature myeloid cells that have grown for over 3 mo in culture but eventually terminate as differentiated, mature granulocytes and monocyte-macrophages. Application of these techniques to other sources of fresh human leukocytes (bone marrow and adult peripheral blood) resulted in only short-term proliferation of myeloid cells. The techniques described can be used for the routine expansion of immature myeloid and monocytoid cell populations, particularly from newborns, and should be useful for systematic studies of normal myeloid- monocytoid cell growth and differentiation and providing normal control cells in studies employing human leukemic myeloid cells.  相似文献   
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