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991.
Kong J Ma L Gollub RL Wei J Yang X Li D Weng X Jia F Wang C Li F Li R Zhuang D 《Journal of alternative and complementary medicine (New York, N.Y.)》2002,8(4):411-419
OBJECTIVES: To characterize the brain activation patterns evoked by manual and electroacupuncture on normal human subjects. DESIGN: We used functional magnetic resonance imaging (fMRI) to investigate the brain regions involved in electroacupuncture and manual acupuncture needle stimulation. A block design was adopted for the study. Each functional run consists of 5 minutes, starting with 1-minute baseline and two 1-minute stimulation, the interval between the two stimuli was 1 minute. Four functional runs were performed on each subject, two runs for electroacupuncture and two runs for manual acupuncture. The order of the two modalities was randomized among subjects. During the experiment, acupuncture needle manipulation was performed at Large Intestine 4 (LI4, Hegu) on the left hand. For each subject, before scanning started, the needle was inserted perpendicular to the skin surface to a depth of approximately 1.0 cm. Electroacupuncture stimulation was delivered using a continuous rectangular wave form (pulse width 30 ms) at a frequency of 3 Hz. For manual acupuncture, the needle was rotated manually clockwise and counterclockwise at a rate of about 180 times per minute (3 Hz). SUBJECTS: Eleven right-handed, normal, healthy volunteer adults, 6 male and 5 female, ages 21-64 participated in the experiment. RESULTS: Results showed that electroacupuncture mainly produced fMRI signal increases in precentral gyrus, postcentral gyrus/inferior parietal lobule, and putamen/insula; in contrast, manual needle manipulation produced prominent decreases of fMRI signals in posterior cingulate, superior temporal gyrus, putamen/insula. CONCLUSION: These results indicate that different brain networks are involved during manual and electroacupuncture stimulation. It suggests that different brain mechanisms may be recruited during manual and electroacupuncture. 相似文献
992.
The central melanocortin system affects the hypothalamo-pituitary thyroid axis and may mediate the effect of leptin 总被引:3,自引:0,他引:3 下载免费PDF全文
Kim MS Small CJ Stanley SA Morgan DG Seal LJ Kong WM Edwards CM Abusnana S Sunter D Ghatei MA Bloom SR 《The Journal of clinical investigation》2000,105(7):1005-1011
Prolonged fasting is associated with a downregulation of the hypothalamo-pituitary thyroid (H-P-T) axis, which is reversed by administration of leptin. The hypothalamic melanocortin system regulates energy balance and mediates a number of central effects of leptin. In this study, we show that hypothalamic melanocortins can stimulate the thyroid axis and that their antagonist, agouti-related peptide (Agrp), can inhibit it. Intracerebroventricular (ICV) administration of Agrp (83-132) decreased plasma thyroid stimulating hormone (TSH) in fed male rats. Intraparaventricular nuclear administration of Agrp (83-132) produced a long-lasting suppression of plasma TSH, and plasma T4. ICV administration of a stable alpha-MSH analogue increased plasma TSH in 24-hour-fasted rats. In vitro, alpha-MSH increased thyrotropin releasing hormone (TRH) release from hypothalamic explants. Agrp (83-132) alone caused no change in TRH release but antagonized the effect of alpha-MSH on TRH release. Leptin increased TRH release from hypothalami harvested from 48-hour-fasted rats. Agrp (83-132) blocked this effect. These data suggest a role for the hypothalamic melanocortin system in the fasting-induced suppression of the H-P-T axis. 相似文献
993.
Experimental autoimmune thyroiditis. In vitro cytotoxic effects of T lymphocytes on thyroid monolayers 总被引:5,自引:0,他引:5 下载免费PDF全文
Effector mechanisms in experimental autoimmune thyroiditis (EAT) were studied in vitro by establishing a cytotoxicity system with thyroid target cells. Lymph node cells (LNC) from popliteal and inguinal lymph nodes were obtained from CBA/J mice (8-10 wk old) 12-18 d after immunization with 120 micrograms mouse thyroglobulin (MTg) in complete Freund's adjuvant (0.2 ml to both hind footpads and thighs) and were cultured with MTg (10-50 micrograms/ml). On day 5 of culture, viable LNC were added to labeled thyroid monolayers and their cytoxicity was assayed after 16 h. Functional thyroid target cells, as reflected by MTg production for up to 9 d, were prepared by adding 1 mM dibutyryl adenosine 3',5'-cyclic monophosphate and 60 microU thyroid-stimulating hormone/ml to the culture medium. On days 5-7, confluent monolayers were labeled with 111In and used as targets. Specific 111In-release ranged from 56 to 85%. The cytotoxic response is MTg specific and H-2 restricted. Pretreatment of thyroid target cells with rabbit antiserum to MTg completely inhibited cytotoxicity. Pretreatment with mouse antiserum to either Kk or Dk products resulted in approximately 50% inhibition, whereas the combined use of both antisera led to total inhibition. No cytotoxicity was observed when control BALB/c thyroid cultures were the target cells. The kinetics of the expansion of Thy-1+ cytotoxic cells by in vitro exposure to MTg were then studied. The cytotoxic response required 5 d to develop and was abolished by treating LNC on day 4 with monoclonal antibody to Lyt-1.1, but not to Lyt-2.1, plus complement. In contrast, by day 5, cytotoxicity was abrogated by similar treatment with antiserum to Lyt-2.1, but not to Lyt-1.1. We conclude that cytotoxic cells derived from MTg-immunized mice are Lyt-2-bearing cells but require the presence of Lyt-1-bearing cells for their generation and/or differentiation. 相似文献
994.
Paton NI; Cheong IK; Kong NC; Segasothy M 《QJM : monthly journal of the Association of Physicians》1996,89(7):531-538
To determine the incidence, types and risk factors for infection in
systemic lupus erythematosus (SLE) patients in Kuala Lumpur, Malaysia, we
retrospectively reviewed the medical records of 102 patients with definite
SLE attending a specialist clinic. Details of major infections (pneumonia
or severe infection requiring intravenous therapy) and minor infections,
and their time of onset in relation to immunosuppressive therapy and
disease flares were recorded. There were 77 major and 163 minor infections
during 564 patient-years of follow-up. In the month following a course of
pulse methylprednisolone, the incidence of major infection was 20 times
higher and the incidence of minor infection was 10 times higher than at
other periods (p<0.0001). In the month after disease flare, the
incidence of major infection was 10 times higher and the incidence of minor
infection six times higher than at other times (p<0.0001). After
allowing for methylprednisolone therapy and disease flares, there was no
increase in the rate of infections during treatment with azathioprine, oral
or intravenous cyclophosphamide. There was no effect of renal involvement
on infection rate.
相似文献
995.
996.
997.
Zhao G Xu MJ Zhao MM Dai XY Kong W Wilson GM Guan Y Wang CY Wang X 《Kidney international》2012,82(1):34-44
Vascular calcification is a major risk factor of cardiovascular mortality, particularly for patients with end-stage renal disease and diabetes. Although chronic inflammation is one of the etiologic factors, the underlying mechanism is not fully understood. To clarify this, we studied how nuclear factor-kappa B (NF-κB) induction, a mediator of inflammation, might promote vascular calcification. Activation of NF-κB by tumor necrosis factor (TNF) promoted inorganic phosphate-induced calcification in human aortic smooth muscle cells. Pyrophosphate (an inhibitor of calcification) efflux to the extracellular matrix was suppressed along with the decreased expression of ankylosis protein homolog (ANKH), a transmembrane protein that controls pyrophosphate efflux of cells. The restoration of ANKH expression in these cells overcame the decreased pyrophosphate efflux and calcification. Tristetraprolin, a downstream product of NF-κB activation, may mediate destabilization of ANKH mRNA as its knockdown by shRNA increased ANKH expression and decreased calcification. Furthermore, a rat chronic renal failure model, with increased serum TNF levels, activated NF-κB and decreased ANKH levels. In contrast, the inhibition of NF-κB maintained ANKH expression and attenuated vascular calcification both in vivo and in vitro. Both human calcified atherosclerotic lesions and arteries from patients with chronic kidney disease had activated NF-κB and decreased ANKH expression. Thus, TNF-activated NF-κB promotes inflammation-accelerated vascular calcification by inhibiting ankylosis protein homolog expression and consequent pyrophosphate secretion. 相似文献
998.
Pulse pressure variation (PPV) and stroke volume variation (SVV) during mechanical ventilation have been shown to be effective parameters to predict preload responsiveness. Although induced hypertension decreases PPV and SVV, the influences of different vasopressors on PPV and SVV are unknown. 94 patients undergoing elective otologic surgery were randomly divided into three groups: Group P (patients were given phenylephrine), Group D (patients were given dopamine), Group E (patients were given ephedrine). When surgery was ongoing and the circulation state was stable, patients were given the vasopressor to increase the systolic arterial pressure (SAP) to the pre-calculated levels: low level, 10 % < ΔSAP ≤ 20 %; medium level, 20 % < ΔSAP ≤ 30 %; high level, 30 % < ΔSAP ≤ 40 %. When invasive arterial pressure reached the target value, PPV, SVV and other parameters were recorded. Dopamine decreased the PPV and SVV more significantly than ephedrine, but less significantly than phenylephrine. The influences of phenylephrine, dopamine and ephedrine on SVV and PPV are different due to their different pharmacological mechanisms. 相似文献
999.
Beauregard JM Hofman MS Kong G Hicks RJ 《European journal of nuclear medicine and molecular imaging》2012,39(1):50-56
Purpose
Tumour sequestration of radiotracer may lead to decreased bioavailability in healthy tissue resulting in lower absorbed radiation dose to critical organs. This study aims to assess the impact of disease burden, body habitus and urinary excretion on the biodistribution of 68Ga-DOTA-octreotate. 相似文献1000.
Xilin Yang Wing Yee So Ronald C.W. Ma Gary T.C. Ko Alice P.S. Kong Hailu Zhao Andrea O.Y. Luk Christopher W.K. Lam Chung Shun Ho Peter C.Y. Tong Juliana C.N. Chan 《Diabetes care》2009,32(10):1826-1832