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1.
We report a case of vasoactive-agent-induced priapism successfully treated in the emergency department with 10 mg of metaraminol injected into the corpora cavernosa.  相似文献   
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BACKGROUND: Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. OBJECTIVE: The purpose of this study was to determine characteristics of postinfarction ventricular tachycardia in the IBZ. METHODS: A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block were expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (DeltaT) is maximal, so that the degree of wavefront curvature rho proportional, variant DeltaT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum DeltaT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps after tachycardia induction. RESULTS: Mean IBZ thickness was 231 +/- 140 microm at the reentry isthmus and 1440 +/- 770 microm in the outer pathway (P <0.001). Mean curvature rho was 1.63 +/- 0.45 mm(-1) at functional block line locations, 0.71 +/- 0.18 mm(-1) at isthmus entrance-exit points, and 0.33 +/- 0.13 mm(-1) in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32 +/- 0.04 mm/ms at entrance-exit points, 0.42 +/- 0.13 mm/ms for the entire outer pathway, and 0.64 +/- 0.16 mm/ms at outer pathway regions with minimum DeltaT. Model sensitivity and specificity to detect isthmus location was 75.0% and 97.2%. CONCLUSIONS: Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships.  相似文献   
3.
Ten cardiology chest pain patients without clinical evidence of coronary artery disease and with panic disorder were enrolled in an open label trial of alprazolam. Two dropped out at week 3 because of excessive side effects. The eight study completers showed significant decreases in both Hamilton Anxiety and Hamilton Depression scales by week 2 that remained significant by week 8. On the physician's global impression of change since baseline, all completers were rated at least "much improved." Seven experienced a 50% or greater reduction in panic frequency at week 8 compared to baseline. These results suggest that alprazolam is likely to be of benefit to this patient population.  相似文献   
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Percutaneous endoscopic gastrostomy in burn patients   总被引:2,自引:0,他引:2  
Background: Prolonged enteral feedings are required occasionally in seriously burned individuals. We have employed percutaneous endoscopic gastrostomy (PEG) in selected patients who require particularly prolonged access, thus prompting this review. Methods: The PEG procedure was performed under general anesthesia in combination with another surgical procedure using a variety of commercially available needle and guidewire kits in 14 patients. Results: These 14 patients had an average age of 55.2 ± 6.6 years and a burn involving 38 ± 8% of the body surface. Eleven of these patients had suffered an inhalation injury. The tubes were placed an average of 57 ± 10.5 days after injury through unburned and unharvested skin in four patients (28%), healed donor sites in five patients (35%), healed burn in one patient (1%), and grafted burn in four patients (28%). One patient, whose catheter was placed through a grafted fascial excision, developed moderate local wound erosion. Tubes were known to have been left in place as long as 155 days. However, most were removed in rehabilitation hospitals, and we were unable to determine how long most were left in place. We are unaware of any problems with the tubes occurring after discharge from the acute care setting. Conclusions: In selected patients, PEG can provide more comfortable access for prolonged enteral feedings than nasogastric tubes and can be placed with minimal morbidity. Received: 29 March 1998/Accepted: 1 August 1998  相似文献   
6.
Small Heat Shock Proteins (sHSPs) are a diverse family of molecular chaperones that prevent protein aggregation by binding clients destabilized during cellular stress. Here we probe the architecture and dynamics of complexes formed between an oligomeric sHSP and client by employing unique mass spectrometry strategies. We observe over 300 different stoichiometries of interaction, demonstrating that an ensemble of structures underlies the protection these chaperones confer to unfolding clients. This astonishing heterogeneity not only makes the system quite distinct in behavior to ATP-dependent chaperones, but also renders it intractable by conventional structural biology approaches. We find that thermally regulated quaternary dynamics of the sHSP establish and maintain the plasticity of the system. This extends the paradigm that intrinsic dynamics are crucial to protein function to include equilibrium fluctuations in quaternary structure, and suggests they are integral to the sHSPs’ role in the cellular protein homeostasis network.  相似文献   
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Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T1 weighted and axial T2 weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies.  相似文献   
9.
Glomus tumors (GT) have been classified among tumors of perivascular smooth muscle differentiation, together with myopericytoma, myofibroma/tosis, and angioleiomyoma, based on their morphologic overlap. However, no molecular studies have been carried out to date to investigate their genetic phenotype and to confirm their shared pathogenesis. RNA sequencing was performed in three index cases (GT1, malignant GT; GT2, benign GT and M1, multifocal myopericytoma), followed by FusionSeq data analysis, a modular computational tool developed to discover gene fusions from paired‐end RNA‐seq data. A gene fusion involving MIR143 in band 5q32 was identified in both GTs with either NOTCH2 in 1p13 in GT1 or NOTCH1 in 9q34 in GT2, but none in M1. After being validated by FISH and RT‐PCR, these abnormalities were screened on 33 GTs, 6 myopericytomas, 9 myofibroma/toses, 18 angioleiomyomas and in a control group of 5 sino‐nasal hemangiopericytomas. Overall NOTCH2 gene rearrangements were identified in 52% of GT, including all malignant cases and one NF1‐related GT. No additional cases showed NOTCH1 rearrangement. As NOTCH3 shares similar functions with NOTCH2 in regulating vascular smooth muscle development, the study group was also investigated for abnormalities in this gene by FISH. Indeed, NOTCH3 rearrangements were identified in 9% of GTs, all present in benign soft tissue GT, one case being fused to MIR143. Only 1/18 angioleiomyomas showed NOTCH2 gene rearrangement, while all the myopericytomas and myofibroma/toses were negative. In summary, we describe novel NOTCH1–3 rearrangements in benign and malignant, visceral, and soft tissue GTs. © 2013 Wiley Periodicals, Inc.  相似文献   
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