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排序方式: 共有744条查询结果,搜索用时 15 毫秒
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C M Adema E C van Deutekom-Mulder W P van der Knaap E A Meuleman T Sminia 《Developmental and comparative immunology》1991,15(1-2):17-26
The kinetics of oxygen radical production by phagocytosing hemocytes of the pond snail Lymnaea stagnalis were investigated. After contact had been established between zymosan and hemocytes in monolayers at 0 degrees C, phagocytosis was initiated by a shift to room temperature. Until the internalization phase of phagocytosis was completed, oxidative activity was detected mainly extracellularly (superoxide dismutase inhibitable cytochrome C reduction and peroxidase-catalyzed phenol red oxidation were used for the detection of superoxide and hydrogen peroxide, respectively). Thereafter, extracellular oxygen radical production by phagocytosing hemocytes decreased. Luminol-dependent chemiluminescence activity grew and, after the internalization phase of phagocytosis, remained at a high level, suggesting continued oxygen radical activity intracellularly. These results indicate that contact between zymosan and the hemocyte's plasma membrane stimulates a membrane-bound system to generate and release oxygen radicals. After internalization, this system appears to continue oxygen radical production inside the phagosome. So far, oxygen radical production in snail hemocytes shows many similarities to the mechanism in mammalian leucocytes. 相似文献
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Diagnostic efficacy of the combination of urine cytology, urine analysis and history in the follow-up of bladder carcinoma 总被引:2,自引:0,他引:2
In the follow-up of low stage, low grade transitional cell carcinoma of the bladder, cystoscopy is used as a diagnostic standard. Because of the lack of well defined prognostic parameters, cystoscopic follow-up is based upon empirical grounds. In this study, 82 patients with a primary superficial transitional cell carcinoma of the bladder were studied with respect to the time interval before recurrence. The mean number of cystoscopies leading to detection of recurrence (i.e. the ratio of positive to negative cystoscopy) was reviewed. Eighteen cystoscopies had to be done to detect each recurrence. Because of this excessive number of cystoscopies, the diagnostic value of the combination of red cell count in urine, cytology and history of micturition symptoms and haematuria was assessed in a retrospective study of 86 recurrences of bladder carcinoma. The results indicated that the combination of these non-invasive diagnostic tests may constitute a sensitive procedure for the follow-up of bladder tumours. In the case of T1G3 and muscle-invasive recurrences (greater than T1), the sensitivity rate was 100%. 相似文献
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Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
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CA 125 concentrations in ovarian 'chocolate' cyst fluid can differentiate an endometriotic cyst from a cystic corpus luteum. 总被引:2,自引:0,他引:2
P R Koninckx M Muyldermans P Moerman C Meuleman J Deprest F Cornillie 《Human reproduction (Oxford, England)》1992,7(9):1314-1317
In a prospective study, the concentrations of CA 125, 17 beta-oestradiol and progesterone were assayed in 52 consecutive ovarian cysts, laparoscopically suspected to be endometriomas. Cysts with dark brown 'chocolate' fluid (n = 42) were excised by CO2-laser endoscopy. Cysts with clear fluid were diagnosed by pathology as follicular cysts (n = 5) or pseudoperitoneal cysts (n = 5). Fluids (n = 53) aspirated during echo-guided puncture for in-vitro fertilization (IVF) were assayed simultaneously. Of the 42 women undergoing a cystectomy, the clinical diagnosis of an endometrioma was confirmed by pathology in only 68%, the other cases being corpora lutea (27%) or follicular cysts (5%). Cyst fluids from corpora lutea had lower CA 125 concentrations (< 1000 IU/ml) together with high 17 beta-oestradiol concentrations (> 2000 pg/ml) and/or high progesterone concentrations (> 100 ng/ml). Endometriotic cysts had either very high CA 125 concentrations (> 10,000 IU/ml) as occurred in 78% or lower CA 125 concentrations (< 1000 IU/ml) together with low 17 beta-oestradiol and/or progesterone concentrations. 'Chocolate' fluid-containing cysts aspirated during IVF had similar concentration profiles of CA 125, 17 beta-oestradiol and progesterone and the diagnoses derived from these concentrations were not contradicted in 19/27 women undergoing a laparoscopy within 4 months. In eight women, however, with high CA 125 concentrations in their cyst fluid, no endometriotic cysts were found at laparoscopy. Only 68% of cysts containing 'chocolate' material were endometriotic cysts and CA 125 could be useful in making this diagnosis. This method is recommended when dark brown fluid is aspirated in IVF. 相似文献
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Variability of skin temperature in the waking monkey 总被引:3,自引:0,他引:3
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In-vitro adhesion of endometrium to autologous peritoneal membranes: effect of the cycle phase and the stage of endometriosis 总被引:5,自引:0,他引:5
Debrock S Vander Perre S Meuleman C Moerman P Hill JA D'Hooghe TM 《Human reproduction (Oxford, England)》2002,17(10):2523-2528
BACKGROUND: Endometrium can adhere to autologous peritoneum. This study was undertaken to determine the effect of the menstrual cycle phase and the presence and stage of endometriosis on in-vitro adhesion of endometrium onto autologous peritoneum. METHODS: This was performed in an academic medical research centre. Sixty-seven subfertile women with a visually normal pelvis (n = 18) and with biopsy-proven endometriosis (n = 49) were included. Endometrial and peritoneal biopsies were obtained at laparoscopy during menstrual, follicular and luteal phase. Endometrium was cultured in vitro with autologous peritoneum, followed by fixation, paraffin embedding, serial sectioning, hematoxylin-eosin and immunohistochemical staining. Endometrial-peritoneal adhesion was evaluated using light microscopy. RESULTS: Endometrial-peritoneal adhesion was observed in approximately 80% of the adhesion assays and was not affected by the phase of the cycle, or by the presence and stage of endometriosis. The continuity of the mesothelial layer was disrupted at the attachment sites. Epithelialization was observed along the edges to integrate the endometrial implant. After adhesion, histological changes were observed within and below the implant. CONCLUSIONS: Endometrium obtained during menstrual, follicular or luteal phase appears to have a similar potential to implant in vitro on autologous peritoneum, and this adhesion process is not affected by the stage of endometriosis. 相似文献