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991.
Adrienne A. Taren Peter J. Gianaros Carol M. Greco Emily K. Lindsay April Fairgrieve Kirk Warren Brown Rhonda K. Rosen Jennifer L. Ferris Erica Julson Anna L. Marsland James K. Bursley Jared Ramsburg J. David Creswell 《Social cognitive and affective neuroscience》2015,10(12):1758-1768
Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n = 130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n = 35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects. 相似文献
992.
Mai Uchida Joseph Biederman John D. E. Gabrieli Jamie Micco Carlo de Los Angeles Ariel Brown Tara Kenworthy Elana Kagan Susan Whitfield-Gabrieli 《Social cognitive and affective neuroscience》2015,10(12):1738-1748
This study investigated the neural basis of individual variation in emotion regulation, specifically the ability to reappraise negative stimuli so as to down-regulate negative affect. Brain functions in young adults were measured with functional Magnetic Resonance Imaging during three conditions: (i) attending to neutral pictures; (ii) attending to negative pictures and (iii) reappraising negative pictures. Resting-state functional connectivity was measured with amygdala and dorsolateral prefrontal cortical (DLPFC) seed regions frequently associated with emotion regulation. Participants reported more negative affect after attending to negative than neutral pictures, and less negative affect following reappraisal. Both attending to negative vs neutral pictures and reappraising vs attending to negative pictures yielded widespread activations that were significantly right-lateralized for attending to negative pictures and left-lateralized for reappraising negative pictures. Across participants, more successful reappraisal correlated with less trait anxiety and more positive daily emotion, greater activation in medial and lateral prefrontal regions, and lesser resting-state functional connectivity between (a) right amygdala and both medial prefrontal and posterior cingulate cortices, and (b) bilateral DLPFC and posterior visual cortices. The ability to regulate emotion, a source of resilience or of risk for distress, appears to vary in relation to differences in intrinsic functional brain architecture. 相似文献
993.
T J Liang Y Baruch E Ben-Porath R Enat L Bassan N V Brown N Rimon H E Blum J R Wands 《Hepatology (Baltimore, Md.)》1991,13(6):1044-1051
We studied 67 HBsAg-negative Israeli patients (36 negative for all HBV serological markers as group 1 and 31 positive for antibodies to HBs and HBc as group 2) with chronic liver disease and cirrhosis of unknown origin using a rapid, sensitive and specific assay for the detection of low levels of hepatitis B virus in serum. This technique uses a high-affinity monoclonal antibody to HBs against an a domain epitope of HBsAg to capture the virion, followed by hepatitis B virus DNA amplification with the polymerase chain reaction. In addition, 55 subjects without liver disease served as controls: Group 3 (n = 32) was negative for all hepatitis B virus markers; group 4 (n = 23) was positive for antibodies to HBs and HBc. We found 11 individuals in group 1 (31%) and 10 in group 2 (29%) harboring low levels of hepatitis B virus DNA in serum. In contrast, no one in group 3 or group 4 was positive by this technique (p less than 0.0001). Using polymerase chain reaction primers spanning other regions of the hepatitis B virus genome and a method of restriction-fragment analysis of polymerase chain reaction-amplified sequences, we detected significant DNA sequence heterogeneity, suggesting infection with distinct hepatitis B virus strains. DNA extracted from paraffin-embedded liver biopsy specimens of 42 patients from groups 1 and 2 was shown to contain hepatitis B virus DNA by polymerase chain reaction in 11 of 12 patients with circulating virion DNA. More important, 18 additional patients whose sera were negative by HBs-antibody capture/polymerase chain reaction amplification had hepatitis B virus DNA sequences in their livers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
Postdischarge management of patients with acute coronary syndrome is often suboptimal, despite their high risk of a subsequent event. Updated American College of Cardiology/American Heart Association guidelines emphasize the need for aggressive modification of risk factors and treatment with antiplatelet, antihypertensive, and lipid-lowering agents commenced in-hospital and continued long-term. Antiplatelet therapy involving aspirin and clopidogrel is the mainstay of secondary risk reduction. Increased adherence to medication and risk factor modification at discharge has been demonstrated with acute care quality improvement initiatives. Extension of these initiatives to postdischarge care will provide data on medication adherence post acute coronary syndrome and functional outcomes in the community setting. Successful secondary prevention of cardiovascular events requires implementation of evidence-based guidelines by physicians, and adherence to pharmacotherapy and lifestyle modifications by patients. Primary care physicians are well placed to influence adherence through their ongoing relationships with patients and can save lives by implementing secondary risk reduction measures after discharge. 相似文献
995.
We describe a new device for treating obstructive sleep apnea (OSA) which is similar to nasal CPAP, but less cumbersome. The device consists of a 7 mm diameter flexible tube terminating at one end in nasal prongs covered with foam cylinders. The foam cylinders are compressed, inserted into the nostrils and released, forming a tight seal. The other end of the catheter is attached to a compressor delivering between 7 and 15 L/min of air. We studied four men and two women with OSA, the first night without treatment and the following night with continuous nasal airflow. A desaturation index was calculated by multiplying the average number of desaturation episodes per hour of sleep times the average maximum desaturation per episode. With continuous nasal airflow there was a significant decrease in all parameters (p less than .025). We conclude that continuous nasal airflow decreased oxyhemoglobin desaturation in patients with OSA and may be useful in patients with mild-to-moderate OSA and in patients who do not tolerate nasal CPAP. 相似文献
996.
M Coscia H D Brown M Miller K Tanaka W E Nicholson K R Parks D N Orth 《The American journal of medicine》1977,62(2):303-307
A 61 year old woman presented with profound hyponatremia and markedly low serum osmolality. Urine osmolality was greater than the serum osmolality, an abnormality that was corrected by water restriction, suggesting inappropriate ADH secretion. Although there were no physical signs of Cushing's syndrome, her serum potassium level was low and markedly elevated levels of plasma and urine corticosteroids were not altered by the administration of large amounts of dexamethasone, suggesting the ectopic ACTH-MSH syndrome. Plasma levels of immunoreactive ACTH and beta-MSH were elevated. At autopsy, a metastastic oat cell carcinoma of the lung, not detected antemortem by chest roentgenograms and bronchoscopy, was found. Immunoreactive ADH, ACTH and beta-MSH were detected in the primary tumor and in metastases to the liver. beta-MSH was also detected in the spleen, in which metastases were observed. This is the first documented case of the simultaneous production of ADH, ACTH and beta-MSH by neoplastic tissue associated with clinical manifestations of the syndrome of inappropriate ADH secretion and the ectopic ACTH-MSH syndrome. 相似文献
997.
Scintigraphic measurements of canine ileocolonic transit. Direct and indirect effects of eating 总被引:2,自引:0,他引:2
Eight dogs were equipped with ileal catheters, 50 cm proximal to the ileocolonic junction, and serosal electrodes at 5, 25, 55, 100, and 150 cm. Transit was assessed by injecting a bolus of 99mTc-diethylenetriamine pentaacetic acid through the ileal catheter and following isotope movements by serial, 4-min scintiscans. Isotope was injected in separate studies: during phase I of an interdigestive myoelectrical cycle, 10 min before a meal, and or 2 or 4 h after a meal (600 ml, 385 kcal, thickened with 4 g guar). At another time, mouth-to-colon transit of the same meal was measured by labeling it with 111In-diethylenetriamine pentaacetic acid and scanning at hourly intervals for 11 h. Transit of isotope through the terminal ileum and entry into the colon was characteristically erratic; long periods of immobility were interspersed with sudden "bolus" movements. In the fasting studies, most sudden movements occurred while phase III (migrating motor complex) of the interdigestive myoelectrical cycle migrated through the last 50 cm of ileum. Passage of a single migrating motor complex through the terminal ileum propelled about one-half the dose of isotope into the colon; complete clearance of the ileum required two or more migrating motor complexes. Immediately after the meal, ileal movements increased transiently; however, these were followed by a period of quiescence. Overall, the time for 50% of the counts to enter the colon was not different when isotope was injected 10 min before the meal from when the injection was made 2 h postprandially (207 +/- 16 min and 162 +/- 25 min, respectively). However, transit of isotope injected 4 h postprandially was significantly faster (91 +/- 13 min). In the fed state, some bolus movements could be related to specific patterns of ileal motility; however, the majority occurred during apparently random "fed-type" motility. In part II, meal marker accumulated faster in the colon after 3-4 h, suggesting that the rapid ileocecal transit at 4 h postcibal was due to increased flow of chyme through the ileum at this time. 相似文献
998.
Dr. Mary Fanning MD PhD FRCP Marc Monte MD Lloyd R. Sutherland MDCM FRCPC FACP MSc Mary Broadhead RN ONC Gerard F. Murphy MD CM MSc Alan G. Harris MD 《Digestive diseases and sciences》1991,36(4):476-480
Seventeen AIDS patients were enrolled in a prospective open-label dose-finding study of octreotide (Sandostatin) therapy for refractory diarrhea. Five were nonevaluable due to progression of AIDS symptomatology, and one was excluded because of lack of confirmation of HIV infection. Five of 11 evaluable patients responded to therapy (45%); two each at 50 g and 100 g, and one at 250 g thrice daily doses. A sixth patient demonstrated a moderate reduction in stool volume at 250 g thrice daily, which, although deemed clinically relevant, did not meet the criteria for response. On discontinuation of therapy, diarrhea recurred in all patients within 1–12 days, and responded to reinitiation of octreotide in those five patients who resumed treatment. Only one of the three patients with concurrent cryptosporidial infection responded to treatment. The drug was well tolerated, with mild symptomatology in three patients. Long-term treatment at a stable dose was effective in three of five treated patients for periods for seven months in one (moderate responder) and one year in two. One patient required dose increases to control symptoms, but after one year of treatment developed severe nausea following injections, which required dose cessation. One patient had partial control of his diarrhea for only three months despite two dose increases. These data suggest that octreotide may be of useful therapeutic value in HIV-associated diarrhea and that further studies are indicated.This study was supported by Sandoz Canada Inc. 相似文献
999.
Serological screening suggests that adult coeliac disease is underdiagnosed in the UK and increases the incidence by up to 12%. 总被引:2,自引:0,他引:2 下载免费PDF全文
Because coeliac disease often presents atypically it is underdiagnosed. It is suggested that the detection rate may be increased by 12% if serology is used to identify cases of occult enteropathy. All adults noted incidentally to be R1 anti-reticulin antibody (ARA) positive in the course of routine autoantibody testing of 6532 sera over one year were followed. None of the eight patients with seropositive serum was suspected of having coeliac disease. All eight had high titres of IgA anti-gliadin and IgA anti-endomysial antibodies, neither of which is detected in a routine autoantibody test, in addition to IgA R1-ARA. On clinical review coeliac disease was considered probable in only one patient, but because of the strong serological evidence of gluten sensitivity, jejunal biopsy was advised in all eight. Seven agreed and all had villous atrophy and crypt hyperplasia in keeping with coeliac disease. Six of the seven presented initially with vague symptoms such as tiredness or arthralgia. These symptoms disappeared after several weeks of gluten withdrawal. Forty two sera showing reticulin staining patterns other than R1 were used as controls. Low titre IgA anti-gliadin was noted in two of 42 but none had IgA anti-endomysial antibody. These 42 cases were not recommended for biopsy. During our study 58 other new adult cases of coeliac disease were diagnosed, primarily on clinical rather than serological grounds, at the four hospitals that request autoantibody studies. Occult coeliac disease detected serologically thus increased the overall incidence of coeliac disease by 12% from 58 to 65 cases. R1-ARA, even in the absence of the expected symptoms and signs of coeliac disease, is an indication for jejunal biopsy and is a reliable indicator of occult coeliac disease. 相似文献
1000.
Dr. John G. Allison M.D. F. M. Brown M.D. J. A. Majeski M.D. 《Diseases of the colon and rectum》1987,30(9):712-714
A case of Crohn's colitis with unusual endoscopic and morphologic appearances is reported. The colitis was asymptomatic and
discovered incidentally. Histologic confirmation was obtained following segmental colectomy. 相似文献