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排序方式: 共有785条查询结果,搜索用时 15 毫秒
101.
WM WONG SK LAM TSM TONG KL CHEUNG VSY TANG HHX XIA KC LAI WHC HU CK CHAN MF YUEN AOO CHAN BCY WONG 《Journal of digestive diseases》2003,4(3):132-135
OBJECTIVE: To evaluate the accuracy of a rapid assay that wasdeveloped to detect Helicobacter pylori antigen in the stool,using the principle of immunochromatography, in the Chinese population. METHODS: Eligible patients without prior treatment of H.pylori were recruited. An in‐house rapid urease test (RUT) andhistology were used as the gold standard. The results of the rapidstool antigen test were compared with the gold standard. RESULTS: Valid rapid stool antigen test results for interpretationwere obtained from 94 consecutive patients (mean age: 52.5, range:22?82 years). Sensitivity, specificity, positive predictivevalue, negative predictive value and accuracy were, respectively, 77.5%,87.0%, 81.6%, 83.9% and 83.0%.The test was easy to perform and results were available within 15 min. CONCLUSION: The rapid stool antigen test using immunochromatography accuratelydiagnoses H. pylori infection in Chinese patients. 相似文献
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106.
CD40 ligand triggered interleukin-6 secretion in multiple myeloma 总被引:11,自引:3,他引:8
Previous studies have suggested that interleukin-6 (IL-6) may mediate growth of multiple myeloma (MM) in either an autocrine or paracrine growth mechanism. However, those molecules which can trigger IL-6 secretion either by tumor cells or non-MM marrow cells are not well characterized. In the present study, we have examined the expression and functional significance of CD40 on MM and plasma cell leukemia (PCL) cells and derived cell lines, as well as long-term bone marrow stromal cells (BMSCs) and derived cell lines. CD40 was expressed on the majority of MM cells (> 90%) and BMSCs (> 70%). Triggering via CD40 using NIH3T3 CD40 ligand transfectant (CD40LT) cells increased (> 30%) cell surface CD80, CD18, CD11a, CD11b, and CD11c expression on MM cell lines. Culture with either fresh or paraformaldehyde fixed NIH3T3 CD40LT cells upregulates IL-6 secretion in MM cells and MM-derived cell lines, as well as normal and MM bone marrow mononuclear cells (BMMCs), BMSCs, and BMSC lines; this effect can be specifically blocked by anti- CD40 monoclonal antibody (MoAb). BMMCs and BMSCs from patients with MM secreted significantly more IL-6 than those from healthy donors (n = 3, P < .001); moreover, after stimulation using CD40L, IL-6 secretion was fourfold greater (n = 3, P < .001) from MM BMMCs and BMSCs than from normal BMMCs and BMSCs. Myeloma (CD38+CD45RA-) cells and non-MM (CD38+CD45RA+, CD38-CD45RA+, and CD38-CD45RA-) BMMCs were separated by dual fluorescence cell sorting. The latter secreted fourfold more IL-6 than the former (n = 2, P < .001). Increased IL-6 secretion (up to 28- fold) and proliferation (Stimulation index 10) by CD38+CD45RA-MM cells was triggered by culture with NIH3T3 CD40LT cells. Finally, anti- CD40MoAb partially (30%) blocked tumor cell to BMSC adhesion-induced IL- 6 secretion. These studies support the view that CD40L may trigger IL-6 secretion by both MM cells and BMSCs and that IL-6-mediated autocrine and paracrine growth mechanisms may be possible in MM. 相似文献
107.
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
108.
乳酸中毒和pH对狗肺血管张力和气体交换功能影响的实验研究 总被引:1,自引:0,他引:1
急性代谢性酸中毒对狗血管张力和气体交换功能的影响进行了研究。当滴入乳酸或盐酸造成急性代谢性酸中毒(pH7.00)时,可引起肺血管收缩,肺动脉压力明显升高,血氧饱和度下降,并且乳酸和盐酸引起的酸中毒对肺动脉平均压影响程度相似,提示肺血管收缩和肺动脉压升高的程度与血中pH值下降关系密切,而与此时血中乳酸水平的高低无关。 相似文献
109.
The aim of our study was to determine the possible pathophysiological mechanisms of hypophosphataemia in a group of 127 patients admitted to hospital for alcohol-related causes. Blood and fresh urine specimens were taken to determine acid-base and electrolyte parameters. Thirty-seven patients (29.1%) had hypophosphataemia (serum phosphorus <0.77 mmol/l) with a range of serum phosphorus of 0.32-0.74 mmol/l. In 17 hypophosphataemic patients inappropriate phosphaturia (FEP04 >20%, TmPO4/GFR<0.80 mmol/l) was evident, possibly due to hypomagnesaemia, metabolic acidosis, metabolic alkalosis, or a proximal tubular defect in phosphate transport. The causes of hypophosphataemia in the remaining 20 patients were alcohol withdrawal syndrome, respiratory alkalosis and diarrhoea. Patients with hypophosphataemia were more often found to have hypomagnesaemia and respiratory alkalosis than normophosphataemic patients. In conclusion, hypophosphataemia is frequently observed in alcoholic patients due to various pathophysiological mechanisms, such as inappropriate phosphaturia, increased phosphorus entry into cells and increased gastrointestinal loss of phosphate. 相似文献
110.
A histologically visible representation of the fingers and palm in primate area 3b and its immutability following long-term deafferentations 总被引:1,自引:1,他引:0
An isomorph of the glabrous hand is visible in primary somato-sensory
cortex (area 3b) of owl monkeys in brain sections cut parallel to the
surface and stained for myelin. A mediolateral row of five ovals, separated
by myelin-light septa, represents digits and corresponds precisely with
cortical sites activated by light touch on individual digits in
microelectrode recordings. A number of caudal ovals relate to pads of the
palm. A more distinct septum separates the hand from the more lateral face
representation. Within the face representation, two large myelin-dense
ovals can be identified that are activated by the upper or lower face in a
caudo-rostral sequence. Accidental finger loss or dorsal column section,
deafferentations that result in reorganization of the physiological map in
area 3b, do not alter the morphological map. The proportions for each digit
and palm in the morphological map do not vary across normal and
deafferented animals. Similar isomorphs were also seen in area 3b of
squirrel and macaque monkeys. We conclude that the anatomical isomorph for
the body surface representation in area 3b is a reliable reflection of
normal cortical organization and may be a common feature of the primate
area 3b. The isomorph can provide a reference in studies of somatotopic
reorganization.
相似文献