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排序方式: 共有343条查询结果,搜索用时 15 毫秒
41.
Ronday HK; Te Koppele JM; Greenwald RA; Moak SA; De Roos JA; Dijkmans BA; Breedveld FC; Verheijen JH 《Rheumatology (Oxford, England)》1998,37(1):34-38
The plasminogen activation system is one of the enzyme systems held
responsible for bone and cartilage degradation in rheumatoid arthritis
(RA). In this study, we evaluated the effect of tranexamic acid (TEA), an
inhibitor of plasminogen activation, on urinary collagen cross-link
excretion and radiological joint damage in rat adjuvant arthritis (AA) and
on urinary collagen cross-link excretion in patients with RA. In the animal
study, adjuvant arthritis was induced in male Lewis rats. From day 7
onward, high-dose TEA (500 mg/kg body weight, once daily) or placebo was
administered orally. Study groups consisted of TEA-treated normal rats (C +
TEA), placebo-treated normal rats (C + plac), AA rats treated with TEA (AA
+ TEA) or with placebo (AA + plac). To monitor joint destruction, urinary
collagen cross-link excretion (pyridinoline, HP; deoxypyridinoline, LP) was
measured by high-performance liquid chromatography at days 14 and 21.
Radiological evaluation of joints was performed at day 21. In the patient
study, TEA was administered to nine patients with RA as adjuvant medication
(approximately 20 mg/kg body weight, three times daily) for 12 weeks.
Urinary HP and LP excretion levels were measured before and during TEA
treatment, and 4 weeks after the cessation of TEA treatment. In AA + TEA
rats, a significant reduction of HP and a tendency towards a reduction of
LP excretion were found compared with AA + plac rats (P < 0.05), at day
14, whereas the HP/LP ratio did not change. No difference was observed in
HP, LP excretion, HP/LP ratio and radiological damage score between the
TEA- and placebo-treated AA rats at day 21. In RA patients, a significant
reduction of HP and LP excretion was found during the TEA treatment period
(P < 0.05). After the cessation of TEA treatment, HP and LP excretion
increased towards baseline levels. No effect on disease activity was
observed. The plasmin antagonist TEA reduced the excretion of collagen
pyridinoline cross-links in both experimental and rheumatoid arthritis. As
such, this study not only supports the involvement of the plasminogen
activation system in the destructive phase of arthritis, but also suggests
a beneficial effect of therapeutic strategies directed against inhibition
of matrix proteolysis.
相似文献
42.
Heterotypic adherence between marrow stromal cells (MSC) and lymphoblastic cells is essential for normal lymphopoiesis and malignant lymphoblastic development. However, the detailed molecular mechanisms by which this heterotypic adherence occurs are poorly understood. The cell-cell interactions between a B-lymphoblastic cell line (UTMB-460) and a pre-B-cell line (NALM-6) with MSC were chosen as models to investigate potential mechanisms and adhesion molecules involved in the apposition between normal and malignant lymphoblastic cells and MSC. A parallel-flow detachment assay (PFDA) and a 51Cr detachment assay, coupled with monoclonal antibody (MoAb) blocking experiments, were used to quantify the attachment of lymphoblastic cells to confluent monolayers of MSC. The apposition between MSC and B-lymphoblastic cells (UTMB-460 cells) was investigated for variable time periods, ranging from 1 minute to 4 hours. Results from the temporal study suggest that the heterotypic adherence of the B-lymphoblastic cells to MSC is a biphasic event and the interactions occur rapidly (< or = 1 minute) after the two cells come into contact. More specifically, the early phase of adherence (< or = 15 minutes) solely involves very late antigen-4 alpha (VLA-4 alpha)/vascular cell adhesion molecule 1 (VCAM- 1) interactions, as evidenced by the nearly complete inhibition (93%) of UTMB-460 cell adherence in the presence of anti-VLA-4 alpha. The late phase (> or = 30 minutes) proceeds despite the continuous presence of anti-VLA-4 alpha. In addition, the late-phase adherence is not affected by MoAbs to LFA-1, CD44, VCAM-1, E-selectin, or L-selectin, which suggests the possible involvement of other adhesion molecules. Adherence of pre-B-lymphoblastic cells (NALM-6) to MSC is also biphasic. Integrin VLA-4 is again a major player in the early phase of pre-B-lymphoblastic cell/MSC interactions. The early phase of adherence may be important in homing of the malignant lymphoblastic cells to the MSC and the late phase in retention of malignant lymphoblastic cells in the bone marrow. 相似文献
43.
Simultaneous sonography and quantitative serum human chorionic gonadotropin (HCG) levels from 126 women with threatened abortion were compared. Of 56 women with normal outcome, 39 (70%) had a gestation sac greater than or equal to 5 mm in mean sac diameter, and in each case the HCG level was 1,800 milli-international units (mIU/ml) or greater. The serum HCG levels strongly correlated with the gestation sac sizes to a mean sac diameter of 25 mm. Of 70 abnormal pregnancies, 31 demonstrated a gestation sac. Of these, 20 women (65%) had disproportionately low HCG levels relative to sac size, including 12 in whom the HCG level was less than 1,800 mIU/ml. One woman with an early molar pregnancy had a disproportionately elevated HCG level. Correlation of sonograms with a simultaneous measurement of serum HCG level is a useful method for evaluating threatened spontaneous abortion. A disproportionately low HCG level relative to gestation sac size is evidence for an abnormal pregnancy. 相似文献
44.
Andrew KC Lam Ken KH Cheng Rex K Lam Christina FC Lau SY Yau 《Clinical & experimental optometry》1996,79(4):167-172
Myopic crescent, refractive error and axial length were previously investigated in Hong Kong Chinese subjects. The myopic crescent was found to correlate with axial length and myopic refraction. In this study, three groups of Hong Kong Chinese with different degrees of myopia were assessed for optic disc ovalness, refractive error and axial length. The axial length was significantly correlated with the degree of myopia, indicating that the myopia was axial in nature. The regression line shows that 0.44 mm of axial elongation would give about one dioptre of increase in myopia. The elliptical ratio of the optic disc was defined as the maximal disc diameter divided by the minimal disc diameter. All three groups showed an oval disc with vertical axis greater and an increased ovalness for the high myopic group with an elliptical ratio from 1.11 in low myopia to 1.29 in high myopia. There is a small amount (about four degrees) of temporal rotation of this vertical oval orientation, which is independent of the amount of myopia. This result shows an association between axial elongation of the globe and optic disc ovalness, in addition to the previously described temporal myopic crescent. Therefore, in myopic subjects, a vertically oval disc may be associated with a myopic refraction rather than glaucoma. 相似文献
45.
Candida albicans strain types from the genitalia of patients with and without Candida infection 总被引:5,自引:0,他引:5
F C Odds A B Abbott T A Reed F E Willmott 《European journal of obstetrics, gynecology, and reproductive biology》1983,15(1):37-43
The strain phenotypes of 266 C. albicans isolates from patients attending a genitourinary clinic were determined on the basis of 9 biochemical tests. Analysis of the strain patterns of isolates from the genitalia showed that there were no statistically significant differences between types associated with clinically overt Candida infection and types isolated in the absence of symptoms of candidosis. This finding accords with the traditional view of C. albicans as an opportunistic pathogen, rather than a species containing some strains of high virulence. In cases where isolations were made from the same patient at different times, or from different anatomical sites in the same patient, it was found that usually, but not always, a patient carried the same phenotype at different sites and different times. Similarly, the same strain type was isolated from the genitalis of both partners in a majority of instances where strains were isolated from consorts; however, this was not the case for a substantial minority of couples, particularly in those where high promiscuity appeared to promote considerable mixture and interchange of the C. albicans genital microflora. 相似文献
46.
47.
48.
Effects of azole antifungals in vitro on host/parasite interactions relevant to Candida infections 总被引:3,自引:0,他引:3
Clotrimazole, fluconazole, itraconazole and ketoconazole were tested for their influence on three aspects of host/parasite interactions in the context of Candida infections. None of clotrimazole, itraconazole or ketoconazole had any effect on the adherence of C. albicans to vaginal epithelial cells, in vitro, regardless of whether the drugs were used to pretreat the fungi or the vaginal cells or were added to the fungus/vaginal cell mixture. Clotrimazole pretreatment of polymorphonuclear leucocytes led to a marked suppression of their ability to phagocytose and kill C. albicans, but fluconazole and ketoconazole had no similar effect. None of these three antifungals affected phagocytosis or killing when they were added to the leucocyte candida mixture or when used to pretreat the fungi. Clotrimazole and ketoconazole both reduced proliferative responses of lymphocyte suspensions to mitogens but fluconazole showed no anti-lymphocyte effect. This difference in action against lymphocytes may help to explain the known disparity between the antifungal effects of fluconazole and ketoconazole against C. albicans in vivo and against experimental candida infections in vitro. Clotrimazole effected a suppression of ATP concentrations in lymphocytes but fluconazole and ketoconazole had no similar effects. 相似文献
49.
Correlation of susceptibility test results in vitro with response in vivo: ketoconazole therapy in a systemic candidiasis model 总被引:3,自引:0,他引:3
In a previous study with flucytosine (5-FC) susceptibility of 40 Candida albicans isolates in vitro proved statistically correlated with response in systemic murine candidiasis in vivo, although exceptions occurred with individual isolates. For the present analogous study with ketoconazole, 58 C. albicans isolates were used of which 38 were from the 5-FC study and 20 were added to equalize the numbers of serotype A (n = 30) and B (n = 28) and to make the range of susceptibility in vitro to ketoconazole continuous and wide. The widest range of ketoconazole susceptibility was noted for the minimal inhibitory concentrations on Kimmig and Casitone agars (0.015-256 micrograms/ml) and disk zone diameters on YNB agar (0-54 mm), whereas with disk tests on other media, the range of 50% inhibitory concentrations, relative inhibition factors and MICs on serum agar remained narrow and/or showed strong ties. The Spearman's rank correlation between the in vitro activities determined with the various parameters showed wide variation consistent with p values from less than 0.001 to greater than 0.05. The serotype B isolates generally were more susceptible than the A isolates (p less than 0.02 for the majority of parameters). Evaluation of response in vivo was hampered by the low activity of ketoconazole on the murine infection with any of the isolates, the range of the ED50's being only 10- greater than 100 mg/kg. The serotype B infections exhibited significantly better response (p less than 0.05) than the serotype A infections. The overall correlation (Spearman's rank) of the susceptibility test results in vitro with the response in vivo was poor (p less than 0.05 for almost all parameters) suggesting very limited if any precise predictive values of the susceptibility tests in vitro with ketoconazole against C. albicans. However, the narrow range of the ED50 suggests relatively little variation in the response of the different isolates in vivo and similarly small variation was also noted in some of the tests in vitro. 相似文献
50.
Hepatocellular carcinoma: assessment of resectability by computed tomography and ultrasound 总被引:2,自引:0,他引:2
A retrospective review of the CT and ultrasound scans from examinations of 30 patients who had hepatocellular carcinoma (hepatoma) was undertaken with special emphasis placed on evaluation of hepatic distribution of tumor, vascular invasion, and extrahepatic spread. Although both CT and ultrasound detected hepatoma in 29 of 30 patients (96%), CT showed more extensive hepatic parenchymal involvement in eight of the patients. Vascular invasion was seen more frequently with ultrasound than with CT. Invasion into the main portal vein was seen by ultrasound in 11 of 30 patients (37%). Extrahepatic spread of tumor was much more frequently detected by CT and was present in 21 of 30 patients (70%). A reasoned approach to the diagnostic workup of hepatomas that will minimize invasive procedures and unnecessary surgery is presented. 相似文献