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81.
Acute impairment of regional myocardial glucose uptake in the apical ballooning (takotsubo) syndrome
Kevin A. Bybee Joseph Murphy Abhiram Prasad R. Scott Wright Amir Lerman Charanjit S. Rihal Panithaya Chareonthaitawee 《Journal of nuclear cardiology》2006,13(2):244-250
BACKGROUND: Apical ballooning syndrome (ABS) is a poorly understood clinical entity characterized by acute, transient systolic dysfunction of the left ventricular (LV) apex in the absence of epicardial coronary artery disease and commonly associated with acute emotional stress. We report abnormal regional myocardial perfusion and glucose uptake in 4 consecutive ABS patients studied using positron emission tomography with 13N-ammonia and 18F-fluorodeoxyglucose within 72 hours of presentation with ABS. METHODS: All patients were postmenopausal females, 3 of whom had a major recent life stress event. Coronary angiography revealed no or minimal obstructive epicardial coronary artery disease. All patients exhibited reduced glucose uptake in the mid-LV and apical myocardial segments, which was out of proportion to perfusion abnormalities in half of the cases. CONCLUSION: In all 4 patients, affected regions subsequently recovered regional LV systolic function within 6 weeks. 相似文献
82.
Background
Resident-led morning report is an integral part of most residency programs and is ranked among the most valuable of educational experiences. The objectives of this study were to evaluate the effect of a resident-as-teacher educational intervention on the educational and teaching experience of morning report. 相似文献83.
Capsaicin-sensitive vagal pulmonary neurones (pulmonary C neurones) play an important role in regulating airway function. During airway inflammation, the level of prostaglandin E2 (PGE2 ) increases in the lungs and airways. PGE2 has been shown to sensitize isolated pulmonary C neurones. The somatosensory correlate of the pulmonary C neurone, the small-diameter nociceptive neurone of the dorsal root ganglion, contains a high percentage of tetrodotoxin-resistant sodium currents (TTX-R I Na ). Therefore, this study was carried out to determine whether these channel currents are involved in the PGE2 -induced sensitization of pulmonary C neurones. We used the perforated patch-clamp technique to study the effects of PGE2 on the TTX-R I Na in acutely cultured capsaicin-sensitive pulmonary neurones that were identified by retrograde labelling with a fluorescent tracer, DiI. We found that the pulmonary neurones sensitive to capsaicin had a higher percentage of TTX-R I Na than that of capsaicin-insensitive pulmonary neurones. PGE2 exposure increased the evoked TTX-R I Na when experiments were performed at both room temperature and at 37°C. Furthermore, stimulation of the adenylyl cyclase/protein kinase A pathway with either forskolin or Sp-5,6-DCl-cBiMPS potentiated the TTX-R I Na in a manner similar to that of PGE2 . We conclude that these modulatory effects of PGE2 on TTX-R I Na play an important role in the sensitization of pulmonary C neurones. 相似文献
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BACKGROUND. Beginning in 1970, a series of patients with Hodgkin disease were treated at the University of Minnesota, after staging laparotomy, with radiation therapy (RT) for Stage I, II, and IIIA Hodgkin disease. This report is an analysis of the results of the treatment and of treatment modifications. METHODS. From 1970 to 1974, all patients were treated with standard RT. In 1975, an analysis of these patients indicated that patients with large mediastinal mass (LMM) and patients with Stage IIIA spleen-positive (IIIAS+) disease had a higher recurrence rates than patients without these factors. Subsequently, a schema of radical radiation therapy (RRT) was devised, which included low-dose lung RT for patients with LMM and low-dose liver RT for patients with IIIAS+ disease. RESULTS. Analysis of the results of the two treatments indicates that the use of low-dose lung RT in patients with LMM and low-dose liver RT in patients with IIIAS+ Hodgkin disease produced survival and recurrence-free survival results equivalent to those achieved by use of combined modality treatment (CMT) or chemotherapy (CT) alone. CONCLUSIONS. The use of RT with whole lung and liver irradiation for patients with LMM and IIIAS+ Hodgkin disease, respectively, produces results that are equivalent to those of CMT or CT alone with the advantage of a decreased incidence of second malignant neoplasms. In addition, patients who do not respond to initial RT have a greater chance of being saved with chemotherapy than do patients initially treated with CMT of being saved with RT. The authors suggest that radical RT is the treatment of choice for patients with LMM and/or IIIAS+ Hodgkin disease. 相似文献
86.
BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome. 相似文献
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Kevin L. Billups 《Current Sexual Health Reports》2004,1(4):137-141
Erectile dysfunction (ED) is often not considered in the same context as such traditional cardiovascular conditions as hypertension,
dyslipidemia, diabetes, or ischemic heart disease. The detection of ED might be one of the most powerful tools to help manage
cardiovascular disease in men. Clinical research suggests that the penile vascular bed is a sensitive indicator of early systemic
endothelial cell or smooth muscle dysfunction. ED could be one of the initial signs of oxidative stress that occurs before
the development of the structural, occlusive cardiovascular disease. ED is becoming a barometer of overall global cardiovascular
risk and should be viewed in this context rather than as “just a problem with the penis.” Asking men about ED as part of the
review of systems is an effective means of practicing preventive vascular medicine. 相似文献
90.
The Food and Drug Administration has established new procedures to make promising investigational drugs available for treatment of patients with immediately life-threatening or serious diseases as early in the drug development process as possible and well before general marketing begins. The purpose of this article is to inform the medical community about these new procedures and to facilitate their implementation. Examples of immediately life-threatening and serious diseases are given and the procedures that physicians should use to obtain a drug under the new regulations are described. The treatment use of zidovudine (Retrovir), while still in the investigational phase, is described as a case study. The article also summarizes the Food and Drug Administration's new procedures under which drug sponsors can charge for investigational drugs. 相似文献