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951.
Intussusception of the ureter is a rare complication of some ureteral diseases. A 49-year-old man was found to have a ureteral
intussusception in the middle part of the right ureter accompanied by a polyp below the invaginated segment of the ureter.
Surgery confirmed the diagnostic imaging findings. Here, we present a case of ureteral intussusception associated with a fibroepithelial
polyp and discuss the radiological characteristics. 相似文献
952.
Nitricoxide(NO)isanewneurotransmitter,existsincentralnervoussystemwidelyandtakespartinnerveconductionandreg-ulationofcerebralbloodstream犤1犦.Butthechangeofnitricoxidesynthetase(NOS)positiveneuronshasn'tbeenreportedindetail.WeadopthistochemicalmethodtoobserveNOSpositiveneuronsinhippocampusCA1ofratswithhyperglycemia.1Materialsandmethods1.1GroupsandanimalmodelsDivide40Wistarratsweighted200~250ginto3groups.Normalcontrolgroup(NC):20rats.Hyperglycemiagroup(D… 相似文献
953.
Raimund Erbel Junbo Ge Günther Görge Michael Haude 《The international journal of cardiovascular imaging》1995,11(1):9-18
A new technique has been developed to compute left ventricular (LV) time activity curves from gated blood pool (GBP) studies without the use of manual, semiautomated or fully automated edge detection algorithms. The method utilizes the correlation of entropy calculated from the counts of a fixed region of interest covering the left ventricle during a cardiac cycle to compute the LV volume curve for a new patient. The new LV volume curve is obtained through interpolation of those volume curves of a data base which are associated with the closest variations in normalized entropy to the new one. The computed LV time activity curves agree with those obtained from manual or fully automated outlines of the left ventricle within 9 percent for the selected set of 67 patients demonstrating the potential of the method. The accuracy of calculated LV volume curves can be improved theoretically to any degree by increasing the number of cases in the data base of known statistical feature vectors associated with the LV images and LV volume curves. The new method for computation of LV curves is very efficient and robust when compared to traditional techniques. 相似文献
954.
Andre J. Plate Amelia Aldao Jean M. Quintero Douglas S. Mennin 《Cognitive therapy and research》2016,40(6):733-746
Recent research has emphasized the importance of studying the interaction between adaptive and maladaptive emotion regulation strategies in predicting mental health. In this respect, putatively maladaptive strategies (e.g., avoidance) have been found to moderate the link between putatively adaptive strategies (e.g., reappraisal) and psychopathology symptoms (e.g., Aldao and Nolen-Hoeksema in J Abnorm Psychol 121(1):276–281, 2012; Aldao et al. in J Anxiety Disord 28(4):382–389, 2014). Moreover, this line of work suggests that the direction of this moderation might vary as a function of symptom severity. However, research has yet to: (1) simultaneously examine how this interaction differs between clinical and non-clinical groups, and (2) test the interaction between specific emotion regulation strategies rather than composite scores of adaptive and maladaptive strategies. Doing so is essential in order to develop a more sophisticated understanding of the disturbances in the use of emotion regulation strategies in psychopathology. To that end, we investigated the interaction between reappraisal and emotional nonacceptance in participants diagnosed with generalized anxiety disorder (GAD) and non-anxious controls. In the GAD group, there was a negative association between reappraisal and disability only when the use of nonacceptance was low, suggesting that the use of maladaptive strategies might interfere with the benefits typically associated with utilizing adaptive strategies. In the non-anxious group, there was a negative association between reappraisal and disability and depression symptoms, only when the use of nonacceptance was high, likely reflecting a compensatory and flexible use of regulation strategies. These findings highlight the importance of modeling interactions between specific emotion regulation strategies when seeking to understand their relationship to psychological functioning in GAD. 相似文献
955.
Kiuchi S Teraoka K Koizumi K Takazawa K Yamashina A 《The international journal of cardiovascular imaging》2007,23(2):237-241
We report a case in which late gadolinium enhancement (LGE) and 67-Ga scintigraphy were useful for the diagnosis of cardiac
sarcoidosis and for the evaluation of the disease activity.The patient was a 60-year-old woman who had been diagnosed as having
eye sarcoidosis when she was 48. Two years previously her electrocardiogram had shown abnormalities but the coronary angiography
had shown normal coronary arteries; however, an aneurysm was detected in the apical portion by left ventriculography. A II
degree AV block was noted on the electrocardiogram and she was referred to us for further detailed evaluation. Since the biopsy
findings of skin eruptions on both eyelids indicated an epithelial cell granuloma, she was diagnosed as having cutaneous sarcoidosis.
On the 67-Ga scintigram, myocardial accumulation of gallium was recognized, and on cardiovascular magnetic resonance (CMR),
LGE was recognized. She was diagnosed as cardiac sarcoidosis and steroid therapy started with 30 mg prednisolone. The myocardial
accumulation of gallium on the 67-Ga scintigram disappeared after the 30th day of steroid therapy. On the other hand, no changes
in LGE patterns were seen after steroid therapy. In this case, LGE was useful for the diagnosis of cardiac sarcoidosis, and
67-Ga scintigram was useful for the evaluation of the disease activity. This case shows that both imaging techniques are important
for the diagnosis of cardiac sarcoidosis and evaluation of the disease. 相似文献
956.
Hoedemaekers CW Ezzahti M Gerritsen A van der Hoeven JG 《Critical care (London, England)》2007,11(4):R91
Background
Temperature management is used with increased frequency as a tool to mitigate neurological injury. Although frequently used, little is known about the optimal cooling methods for inducing and maintaining controlled normo- and hypothermia in the intensive care unit (ICU). In this study we compared the efficacy of several commercially available cooling devices for temperature management in ICU patients with various types of neurological injury. 相似文献957.
Heart failure (HF) is a chronic condition that is expected to increase in incidence along with increased life expectancy and
an aging population. As the incidence of HF increases, the cost to national healthcare budgets is expected to run into the
billions. The costs of lost productivity and increased social reliance on state support must also be considered. Recently,
acute myocardial infarction (AMI) has come to be seen as the major contributing factor to HF. Although thrombolysis may restore
coronary perfusion after an AMI, it may also introduce ischemic reperfusion injury (IRI). In an attempt to ameliorate sustained
protein damage caused by IRI, endogenous chaperone proteins known as heat shock proteins (HSPs) are induced as a consequence
of the stress of IRI. Recently, hyperbaric oxygen has been shown to induce the production of HSPs in noncardiac tissue, with
a resultant protective effect. This current opinion review article suggests a possible role for hyperbaric oxygen, as a technologically
modern drug, in augmenting the induction of endogenous HSPs to repair and improve the function of failing hearts that have
been damaged by AMI and IRI. In addition, this simple, safe, noninvasive drug may prove useful in easing the economic burden
of HF on already overextended health resources. 相似文献
958.
The general practitioner with a special interest in headache offers an important contribution to the management of headache
in primary care where the majority of presentations take place. A number of guidelines have been developed for neuroradiological
investigation of headache, but their clinical utility and relevance is not known. Fourteen general practitioners with a special
interest in headache recorded consecutive headache consultations over a 3-month period, whether patients were investigated
with neuroradiology and if so the reason for investigation and outcome. Reason for investigation was compared to the guidelines
published for the use in primary care. 895 patients were seen, of whom 270 (30.1%) were investigated. 47% of indications were
outside the guidance framework used, the most common reason for investigation being reassurance. Of those investigated, 5.6%
showed positive findings but only 1.9% of findings were felt to be of clinical significance. General practitioners with a
special interest investigated with neuroradiology a greater level than general practitioners, but less than neurologists.
However, yields of significant findings are broadly comparative across all groups. This report confirms other studies that
suggest that even when there is a high level of clinical suspicion, yields of significant findings are very low. 相似文献
959.
Yasutomo Fujii Nobuyuki Taniguchi Yi Wang Kouichiro Shigeta Kiyoka Omoto Kouichi Itoh Jing-Wen Tsao Kenji Kumazaki Takashi Itoh Tomotsugu Takayama 《Journal of Medical Ultrasonics》2004,31(2):91-98
Purpose We used texture analysis in conjunction with an alternative method of analyzing the amplitude histogram using a radiofrequency (RF) signal to differentiate ultrasonograms of normal and cirrhotic livers. This method segments the region of interest (ROI) into multiple layers (sub-ROIs). In each sub-ROI of a homogeneous medium, the histogram of enveloped-amplitude of RF backscattered echoes resembles a Rayleigh distribution. Theoretically, the values of the signal-to-noise ratio (SNR), skewness, and kurtosis for Rayleigh statistics are constant and independent of the mean scattering intensity, which is contributed by such undesirable effects as tissue attenuation, beam diffraction, and incident waveforms. These values, which averaged overall sub-ROI, should provide an unbiased estimator.Methods We studied 36 normal livers and 28 cirrhotic livers, all confirmed by clinical findings including laboratory and pathology data; the SNR, skewness, and kurtosis values of the disease groups were compared. At the same time, these values were estimated using the conventional method, which did not segment the ROI into multiple sub-ROIs. The unpaired t-test was used to determine statistical significance.Results With the new method, all values obtained from cirrhotic livers differed significantly from those obtained from normal livers, and the standard deviation of these values was smaller than those obtained using the conventional method.Conclusions These results suggest that the new method can be used to diagnose the cirrhotic liver objectively.This article is translated from the Japanese version, which was published in J Med Ultrasonics 2001;28:J25–33 相似文献
960.
Ye P Rodriguez FH Kanaly S Stocking KL Schurr J Schwarzenberger P Oliver P Huang W Zhang P Zhang J Shellito JE Bagby GJ Nelson S Charrier K Peschon JJ Kolls JK 《The Journal of experimental medicine》2001,194(4):519-527
Bacterial pneumonia is an increasing complication of HIV infection and inversely correlates with the CD4(+) lymphocyte count. Interleukin (IL)-17 is a cytokine produced principally by CD4(+) T cells, which induces granulopoiesis via granulocyte colony-stimulating factor (G-CSF) production and induces CXC chemokines. We hypothesized that IL-17 receptor (IL-17R) signaling is critical for G-CSF and CXC chemokine production and lung host defenses. To test this, we used a model of Klebsiella pneumoniae lung infection in mice genetically deficient in IL-17R or in mice overexpressing a soluble IL-17R. IL-17R-deficient mice were exquisitely sensitive to intranasal K. pneumoniae with 100% mortality after 48 h compared with only 40% mortality in controls. IL-17R knockout (KO) mice displayed a significant delay in neutrophil recruitment into the alveolar space, and had greater dissemination of K. pneumoniae compared with control mice. This defect was associated with a significant reduction in steady-state levels of G-CSF and macrophage inflammatory protein (MIP)-2 mRNA and protein in the lung in response to the K. pneumoniae challenge in IL-17R KO mice. Thus, IL-17R signaling is critical for optimal production of G-CSF and MIP-2 and local control of pulmonary K. pneumoniae infection. These data support impaired IL-17R signaling as a potential mechanism by which deficiency of CD4 lymphocytes predisposes to bacterial pneumonia. 相似文献