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521.
Hunt RH Xiao SD Megraud F Leon-Barua R Bazzoli F van der Merwe S Vaz Coelho LG Fock M Fedail S Cohen H Malfertheiner P Vakil N Hamid S Goh KL Wong BCY Krabshuis J Le Mair A 杜颖 戴宁 《胃肠病学》2011,16(7):423-428
世界上有一半人口感染幽门螺杆菌(H.pylori),其感染率因地理位置、种族、年龄和社会经济状况不同而存在很大差异.在发展中国家较高.发达国家较低。但总体而言,近年世界许多地区的H.pylori感染率均呈下降趋势。 相似文献
522.
O Saito CI Svensson MW Buczynski K Wegner X-Y Hua S Codeluppi RH Schaloske RA Deems EA Dennis TL Yaksh 《British journal of pharmacology》2010,160(7):1754-1764
Background and purpose:
Toll-like receptor 4 (TLR4) expressed on spinal microglia and astrocytes has been suggested to play an important role in the regulation of pain signalling. The purpose of the present work was to examine the links between TLR4, glial activation and spinal release of prostaglandin E2 (PGE2) and tumour necrosis factor (TNF), and the role these factors play in TLR4-induced tactile allodynia.Experimental approach:
Toll-like receptor 4 was activated by intrathecal (i.t.) injection of lipopolysaccharide (LPS) and KDO2-Lipid A (KDO2) to rats. Tactile allodynia was assessed using von Frey filaments and cerebrospinal fluid collected through spinal dialysis and lumbar puncture. PGE2 and TNF levels were measured by mass spectometry and elisa. Minocycline and pentoxifylline (glia inhibitors), etanercept (TNF-blocker) and ketorolac (COX-inhibitor) were given i.t. prior to injection of the TLR4-agonists, in order to determine if these agents alter TLR4-mediated nociception and the spinal release of PGE2 and TNF.Key results:
Spinal administration of LPS and KDO2 produced a dose-dependent tactile allodynia, which was attenuated by pentoxifylline, minocycline and etanercept but not ketorolac. Both TLR4 agonists induced the spinal release of PGE2 and TNF. Intrathecal pentoxifylline blunted PGE2 and TNF release, while i.t. minocycline only prevented the spinal release of TNF. The release of PGE2 induced by LPS and KDO2 was attenuated by i.t. administration of ketorolac.Conclusions and implications:
Activation of TLR4 induces tactile allodynia, which is probably mediated by TNF released by activated spinal glia. 相似文献523.
Temporomandibular joint clicking with nonreducing anterior displacement of the meniscus 总被引:1,自引:0,他引:1
Patients who have temporomandibular joint (TMJ) clicking and pain are assumed to have an anterior displacement of the meniscus with reduction on opening of the jaw. On the basis of this assumption, these patients are treated nonsurgically with splint therapy. Of 301 TMJs examined, 108 (36%) produced clinically audible clicks on opening, closing, or both. Fluoroscopy and arthrotomography studies for 16 (15%) showed anteriorly displaced menisci without reduction. The mean age of this group was 32 years, with a range of 17-51 years. The duration of the patients' symptoms ranged from three months to eight years (mean 3.7 years). Bilateral degenerative joint disease was noted in 8/16 (50%). Operative findings in four patients suggested the cause of the clicking sound as a frictional impact between the degenerated surface of the condyle and the hypertrophied displaced meniscus. These observations demonstrate that an audible click may not imply a reduction of a displaced meniscus. 相似文献
524.
海南粗榧新碱衍生物HH07A的抗肿瘤作用 总被引:3,自引:0,他引:3
用细胞生长曲线测定法及软琼脂集落形成分析法研究了HH07A对几种肿瘤及正常细胞生长的影响。结果表明,1.5ug·ml-1及3μg·ml-1HH07A能分别明显抑制L1210和HL-60细胞的生长。3种肿瘤细胞对HH07A的敏感性依次为L1210>KB>HL-60,而正常小鼠粒系祖细胞GM-CPC对药物的敏感性则低于前三者,且HH07A3.5μg·ml-1对HL-60细胞无分化诱导作用。HH07A对腹水型L1210白血病小鼠、S180小鼠均有较明显的治疗作用,使L1210荷瘤小鼠、S180荷瘤小鼠存活时间延长。也能抑制S180实体瘤的生长。 相似文献
525.
526.
Influence of HLA-A2 on the effectiveness of platelet transfusions in alloimmunized thrombocytopenic patients 总被引:1,自引:0,他引:1
Platelet transfusions from donors selectively mismatched for cross- reactive and certain non-cross-reactive HLA antigens were found to be more effective in HLA-A2 negative than in HLA-A2 positive, alloimmunized thrombocytopenic patients. The two groups of patients responded equally well to platelets matched for antigens of the HLA-A and B loci. Certain alloimmunized patients negative for HLA-A2 continued to respond satisfactorily to platelets selectively mismatched for non-cross-reactive HLA antigens as long as platelets containing HLA- A2 were avoided. The data indicate that platelet transfusion support can be provided within a broader range of donor-recipient HLA antigenic disparity to HLA-A2 negative alloimmunized patients than to those who are positive for this antigen. 相似文献
527.
In 48 normal weight subjects, 25 females and 23 males, body impedance was measured at multiple frequencies. Two different electrode placements were used, one the commonly used distal electrode placement, in which the source electrodes are on the dorsal sides of the hand and foot and the sensor electrodes are on ankle and wrist, and a second placement, in which the sensor electrodes are placed more proximally, at the knee and elbow. Theoretically a proximal electrode placement could result in more precise estimates of body water compartments. Total body water (TBW) and extracellular water (ECW) were determined using deuterium oxide dilution and bromide dilution, respectively. The aim of the study was to investigate whether proximal electrode placement results in a more precise estimation of TBW and ECW using multifrequency impedance analysis. Correlation coefficients of impedance and the impedance index stature2/impedance) with TBW and ECW were not or were only slightly higher using proximal impedance values, resulting in slight improvement of the estimation error for TBW (0.13 kg) and ECW (0.04 kg). The differences between measured and predicted values (residuals) of TBW and ECW were not correlated with TBW and ECW, but they were correlated with body fat and body water distribution (ECW/TBW). These correlations did not differ between distal and proximal impedance measurements. It is concluded that proximal impedance measurements do not substantially improve the prediction of body water compartments. © 1995 Wiley-Liss, Inc. 相似文献
528.
Jones RH 《Alimentary pharmacology & therapeutics》1996,10(3):233-239
Gastrointestinal disorders are common in the general population, with annual prevalence figures ranging from 20% for irritable bowel syndrome to over 40% for dyspepsia. Less than one-third of patients consult general practitioners for these problems, and anxiety about serious disease and cancer are as important in the decision to consult as symptom severity. Gastrointestinal disorders have significant socioeconomic effects in the community, and account for 10% of the work of general practitioners in the UK. The health economics implications of management in primary care relate principally to the costs of investigation and therapy, notably antisecretory drugs, endoscopy, radiology and specialist referral. Although guidelines based on evidence and agreed between primary and secondary care physicians offer an attractive approach to rationalizing the use of resources, there is at present little health service research evidence on which to base important decisions. For example, in dyspepsia, the role of Helicobacter pylori identification and eradication in an overall management strategy in primary care has yet to be defined. An exploration of the clinical economics of gastrointestinal disorders in general practice raises a number of research questions, which will require the attention of both generalists and specialists. 相似文献
529.
New charts for height, weight, height velocity, and weight velocity are presented for clinical (as opposed to population survey) use. They are based on longitudinal-type growth curves, using the same data as in the British 1965 growth standards. In the velocity standards centiles are given for children who are early- and late-maturing as well as for those who mature at the average age (thus extending the use of the previous charts). Limits of normality for the age of occurrence of the adolescent growth spurt are given and also for the successive stages of penis, testes, and pubic hair development in boys, and for stages of breast and pubic hair development in girls. 相似文献
530.