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111.
Neural classification of lung sounds using wavelet coefficients 总被引:6,自引:0,他引:6
Kandaswamy A Kumar CS Ramanathan RP Jayaraman S Malmurugan N 《Computers in biology and medicine》2004,34(6):523-537
Electronic auscultation is an efficient technique to evaluate the condition of respiratory system using lung sounds. As lung sound signals are non-stationary, the conventional method of frequency analysis is not highly successful in diagnostic classification. This paper deals with a novel method of analysis of lung sound signals using wavelet transform, and classification using artificial neural network (ANN). Lung sound signals were decomposed into the frequency subbands using wavelet transform and a set of statistical features was extracted from the subbands to represent the distribution of wavelet coefficients. An ANN based system, trained using the resilient back propagation algorithm, was implemented to classify the lung sounds to one of the six categories: normal, wheeze, crackle, squawk, stridor, or rhonchus. 相似文献
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113.
Purpose
Gastrointestinal (GI) dysmotility occurs frequently in full-term infants with gastroschisis (GS). Although controversial, preterm delivery of infants with GS has been advocated to prevent the development of GI dysmotility, and understanding the etiology of gestational-related bowel injury may lead to prenatal therapies. Using a fetal rabbit model, the authors assessed in vivo and in vitro GI motility in preterm GS fetuses.Methods
On gestation day 24 (term, 31), surgery was performed in maternal rabbits and GS induced in fetuses, whereas control fetuses underwent sham procedures. On gestation day 29, both groups of fetuses received ultrasound-guided intragastric injection of fluorescein and colored microspheres. Two hours after injection, fetuses were delivered by cesarean section and stomach and small intestine harvested intact. “GI motility” was calculated as the distance traveled by fluorescein divided by total length. In vitro studies of fetal gastric muscle strips contractility responses to bethanechol, a cholinergic agonist, were assessed in an organ bath system. Data were analyzed as paired and unpaired t tests and expressed as means ± SEM.Results
GS reduced fetal body weight and intestinal length compared with controls (28.4 ± 1.4 v. 33.5 ± 1.5 g, 36.9 ± 1.8 v. 25.9 ± 1.2 cm; P < .05, respectively). Fetuses with GS showed markedly reduced in vivo GI motility (51.4 ± 2.9 v 24.8 ± 2.7%; P < .05) and in vitro gastric contractile tension (769 ± 53 v 396 ± 26 mNcm2; P < .05).Conclusions
GI exposure to amniotic fluid reduces intestinal motility and gastric contractility functions in the preterm rabbit fetus. The results suggest that GS-associated impairment of GI neuromuscular functions occurs in utero, before term, and may be responsive to manipulation of amniotic fluid content or other therapeutic interventions. 相似文献114.
Ganesh SK Sundaram PM Biswas J Babu K 《Journal of cataract and refractive surgery》2004,30(11):2371-2376
PURPOSE: To analyze the results of cataract surgery in patients with sympathetic ophthalmia. SETTING: Sankara Nethralaya, Medical Research Foundation, Chennai, India. METHODS: This study comprised 66 patients (132 eyes) with sympathetic ophthalmia seen at the uveitis referral clinic between January 1990 and July 2001; 42 eyes (31.8%) had cataract. Cataract surgery was performed in 17 sympathizing eyes and 1 exciting eye (17 patients). The records of these 18 eyes were retrospectively analyzed. Three eyes had extracapsular cataract extraction (ECCE) with intraocular lens (IOL) implantation, 6 eyes had ECCE without IOL implantation, and 9 eyes had phacoemulsification with IOL implantation. The mean follow-up was 28.7 months (range 3 to 60 months). RESULTS: The causes of sympathetic ophthalmia were penetrating trauma (n = 8 eyes), ocular surgery (n = 6), perforated corneal ulcer (n = 2), and cyclocryotherapy (n = 1). The most common cataract type, present in 7 eyes (38.8%), was mixed (posterior subcapsular and posterior polar). Visual acuity improved after surgery in 13 eyes (72.2%). The main factors impairing visual recovery were submacular scar and optic atrophy, which were sequelae of the sympathetic ophthalmia. Posterior capsule opacification was noted in 14 eyes (77.7%); it was visually significant in 6 eyes. There was no significant difference in postoperative inflammation or disease reactivation between the 3 types of surgery. CONCLUSIONS: Cataract extraction in cases of sympathetic ophthalmia can be safely and successfully performed with vigilant preoperative and postoperative control of inflammation, careful surgical planning, and meticulous surgical technique. The final visual outcome, however, depends on the posterior segment complications of the disease. 相似文献
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116.
Detection of intracranial aneurysms: multi-detector row CT angiography compared with DSA 总被引:56,自引:0,他引:56
Jayaraman MV Mayo-Smith WW Tung GA Haas RA Rogg JM Mehta NR Doberstein CE 《Radiology》2004,230(2):510-518
PURPOSE: To prospectively compare the effectiveness of multi-detector row computed tomographic (CT) angiography with that of conventional intraarterial digital subtraction angiography (DSA) used to detect intracranial aneurysms in patients with nontraumatic acute subarachnoid hemorrhage. MATERIALS AND METHODS: Thirty-five consecutive adult patients with acute subarachnoid hemorrhage were recruited into the institutional review board-approved study and gave informed consent. All patients underwent both multi-detector row CT angiography and DSA no more than 12 hours apart. CT angiography was performed with a multi-detector row scanner (four detector rows) by using collimation of 1.25 mm and pitch of 3. Images were interpreted at computer workstations in a blinded fashion. Two radiologists independently reviewed the CT images, and two other radiologists independently reviewed the DSA images. The presence and location of aneurysms were rated on a five-point scale for certainty. Sensitivity and specificity were calculated independently for image interpretation performed by the two CT image readers and the second DSA image reader by using the first DSA reader's interpretation as the reference standard. RESULTS: A total of 26 aneurysms were detected at DSA in 21 patients, and no aneurysms were detected in 14 patients. Sensitivity and specificity for CT angiography were, respectively, 90% and 93% for reader 1 and 81% and 93% for reader 2. The mean diameter of aneurysms detected on CT angiographic images was 4.4 mm, and the smallest aneurysm detected was 2.2 mm in diameter. Aneurysms that were missed at initial interpretation of CT angiographic images were identified at retrospective reading. CONCLUSION: Multi-detector row CT angiography has high sensitivity and specificity for detection of intracranial aneurysms, including small aneurysms, in patients with nontraumatic acute subarachnoid hemorrhage. 相似文献
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118.
Xirasagar S Samuels ME Stoskopf CH Shrader WR Hussey JR Saunders RP Smith DT 《Journal of health & social policy》2004,19(1):1-35
States are ranked based on the potential of their small group health insurance reforms to enhance health insurance uptake. Reforms were quantified based on their market impact potential. Five dimensions of reforms were identified, Access Improvement, Premium Reduction, Premium Differential Reduction, Continuity of Coverage, and Enhancing Valued Plan Features. The reform indices representing these dimensions were developed based on document review of state statutes, combined with actuarial judgment to identify and assign scores to market-relevant regulations in line with their impact potential. The distribution of the states' reform scores and rankings show wide variation in the depth and focus of their reforms. Only seven of the top ten states on the Total Reform index had consistently higher scores on two or more reform dimensions. The conceptual linkages between specific regulations and the documented small group market problems lead to normative expectations of an association between the depth of state reforms and the prevalence of uninsurance. 相似文献
119.
An unusual case of massive cystic degeneration in an uterine leiomyoma measuring 21 cm in diameter, in a 40 year old female is being presented. It was diagnosed as a cystic adnexal tumor on ultrasonogram. Interlacing bundles of smooth muscle were identified in the cyst wall, which was confirmed on special stains. The differential diagnoses considered in this case are discussed. To the best of our knowledge, this is the largest cystic degeneration in an uterine leiomyoma reported in the literature. 相似文献
120.
Post kala-azar mucosal leishmaniasis (PKML) is relatively rare in the Indian subcontinent. We describe an ulcerative variant of PKML with nasal involvement in a Nepalese adult male. He had ulcerated plaque over the upper lip with extensive involvement of nasal columella and septum. He came from endemic area for kala-azar and had a previous history of kala-azar. There were plenty of LD bodies in microsections and FNA of submandibular lymph node. 相似文献