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41.
Glauber T Silva Alejandro C Frery Mostafa Fatemi 《Computerized medical imaging and graphics》2006,30(5):321-327
We study the image formation of vibro-acoustography systems based on a concave sector array transducer taking into account depth-of-field effects. The system point-spread function (PSF) is defined in terms of the acoustic emission of a point-target in response to the dynamic radiation stress of ultrasound. The PSF on the focal plane and the axis of the transducer are presented. To extend the obtained PSF to the 3D-space, we assume it is a separable function in the axial direction and the focal plane of the transducer. In this model, an image is formed through the 3D convolution of the PSF with an object function. Experimental vibro-acoustography images of a breast phantom with lesion-like inclusions were compared with simulated images. Results show that the experimental images are in good agreement with the proposed model. 相似文献
42.
Rachel N. Pauls Jeffrey L. Segal W. Andre Silva Steven D. Kleeman Mickey M. Karram 《International urogynecology journal》2006,17(6):576-580
The purpose of this study was to evaluate sexual function in women referred to a urogynecology practice. All new patients were mailed an optional female sexual function index (FSFI) in conjunction with their history forms; other sexual function information was obtained during the physician interview. Over 6 months, four hundred fifty new patients were enrolled. Of these, 243 (54%) were not sexually active. Reasons listed for sexual inactivity included partner problems/no partner (32%), low desire (14%), prolapse (10%), and pain (10%). There were several differences between sexually active and non-sexually active participants; however, after a multivariate analysis, only age, marital status, and stage/grade 1–2 of prolapse remained significant. One hundred nine sexually active patients completed the FSFI; the majority was sexually active two to four times per month. Female sexual dysfunction was noted in 70 (64%) patients. Lowest scores were noted for the domain of desire, followed by arousal, orgasm, lubrication, satisfaction, and pain. Reduced frequency of intercourse was the only factor significantly associated with dysfunction. Ninety-four percent were not embarrassed by the survey. Overall, sexual inactivity is common in patients presenting for urogynecologic care. Those that are sexually active report low rates of sexual activity and high rates of sexual dysfunction. Most sexually active patients will accept a sexual function questionnaire as part of their routine assessment.This research was presented at the American College of Obstetricians and Gynecologists annual clinical meeting, May 10, 2005, San Francisco, CA, USA. 相似文献
43.
Marcondes C Fran?a Maria E Calcagnotto Jaderson C da Costa Iscia Lopes-Cendes 《Movement disorders》2006,21(7):1051-1053
Spinocerebellar ataxia (SCA) types 2 and 3 are autosomal-dominant neurodegenerative disorders caused by mutations in two different genes. We identified mutations for SCA2 and SCA3 segregating simultaneously in a single Brazilian family. The index patient had SCA2, whereas her two second-degree cousins had SCA3. Disease was more rapidly progressive in the SCA2 patient, who presented severe brainstem and pancerebellar atrophy, as opposed to the two SCA3 patients, who had only mild cerebellar vermian atrophy. In such situations, molecular confirmation of all patients may avoid misdiagnosis of SCA subtypes and eventual errors in predictive testing of unaffected family members. 相似文献
44.
PINK1 mutations in sporadic early-onset Parkinson's disease. 总被引:5,自引:0,他引:5
Eng-King Tan Kenneth Yew Eva Chua K Puvan Hui Shen Esther Lee Kim-Yoong Puong Yi Zhao Ratnagopal Pavanni Meng-Cheong Wong Dominic Jamora Deidre de Silva Kyaw-Thu Moe Fung-Peng Woon Yih Yuen Louis Tan 《Movement disorders》2006,21(6):789-793
Pathogenic PINK1 mutations have been described in PARK6-linked Parkinson's disease (PD) patients of Asian origin. However, data on the frequency of PINK1 mutations in sporadic early-onset Parkinson's disease (EOPD) Asian patients are lacking. The objectives of this study were to report the frequency of PINK1 mutations of sporadic EOPD in an Asian cohort comprising of ethnic Chinese, Malays, and Indians, and to highlight a PINK1-positive patient who presented with restless legs symptoms. Eighty consecutive sporadic EOPD patients from the movement disorder clinics of two major tertiary institutions in the country were included. We performed sequence analysis of all the coding and exon-intron junctions of the PINK1 using specific primer sets. In addition, we genotyped polymorphisms detected from the analysis in a group of sporadic PD patients and controls. Three different mutations (two homozygous nonsense and one heterozygous missense) in the putative kinase domain were found in three patients, giving a 3.7% frequency of PINK1 mutations in our EOPD cohort. All the mutations were absent in 200 healthy controls. One patient with a novel homozygous nonsense PINK1 mutation presented unusually with restless legs symptoms. Separately, analysis of the frequency of four PINK1 polymorphisms in a group of sporadic PD and controls did not reveal any significant differences. We highlight a 3.7% frequency of PINK1 mutations in an Asian cohort (ethnic Chinese, Malay, and Indian) of EOPD. The phenotypic spectrum associated with PINK1-positive patients may be wider than previously reported. Polymorphisms of PINK1 do not appear to modulate risk of PD in our population. 相似文献
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46.
Mariela Dutra Gontijo Moura Soraya de Mattos Camargo Grossmann Linaena Méricy da Silva Fonseca Maria Inês Barreiros Senna Ricardo Alves Mesquita 《Journal of oral pathology & medicine》2006,35(6):321-326
BACKGROUND: Oral hairy leukoplakia (OHL) may be an indicator of the progression of Human Immunodeficiency Virus (HIV)-induced immuno-depression, and the evaluation of risk factors leading to OHL is important in the management of these HIV-infected patients. However, there are few studies that analyze risk factors leading to OHL in the Brazilian population. The aim of this case-control study is to present data about prevalence rates and risk factors leading to OHL in a sample of HIV-infected adults in Brazil. METHODS: This case-control study included 111 HIV-infected patients treated at a clinic for sexually transmitted diseases and HIV. In the initial examinations with dentists, variables were collected from all patients. Diagnosis of OHL was performed in accordance with the International Classification System and cytological features. The Fisher and the chi-squared tests were used for statistical analysis. The proportional prevalence and odds ratio were estimated. RESULTS: Outcome presented a positive, statistically significant association among the presence of OHL and viral load of 3000 copies/mul or greater (P = 0.0001; odds ratio (OR) = 5.8), presence of oral candidiasis (P = 0.0000; OR = 11.1), previous use of fluconazole (P = 0.0000; OR = 24.6), and use of systemic acyclovir (P = 0.032; OR = 4.3). Antiretroviral medication presented a negative, statistically significant association with the presence of OHL (P = 0.002; OR = 8.4). CONCLUSIONS: Prevalence of OHL was 28.8%. Viral load, oral candidiasis, previous use of fluconazole, and systemic acyclovir were determined to be risk factors for OHL. Antiretroviral medication proved to be protective against the development of OHL. 相似文献
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49.
A prospective study of 17 cases of microsurgical reversal of tubal sterilization by a combined approach of laparoscopy and minilaparotomy was performed. Inclusion criteria included age less than 43; weight less than ideal body weight plus 20%; documentation of ovulation; 2 cm of proximal oviduct on hysterosalpingography; and a normal semen analysis or postcoital test. A comparison group of the 5 cases of sterilization reversal performed by a standard inpatient technique during the same period was analyzed. The study technique was performed on an outpatient basis in 15 of the 17 cases, 12 patients (71%) conceived 13 intrauterine pregnancies, one ectopic pregnancy occurred, and total patient costs and time until return to work were significantly less with the study versus standard technique. 相似文献
50.
B. Bogin P. Smith A.B. Orden M.I. Varela Silva J. Loucky 《American journal of human biology》2002,14(6):753-761
Maya families from Guatemala migrated to the United States in record numbers from the late 1970s to the early 1990s. Births to Maya immigrant women have created a sizable number of Maya American children. The height and sitting height of 5 to 12 years children (n = 431) were measured in 1999 and 2000. Leg length was estimated and the sitting height ratio was calculated. These data were compared with a sample of Maya children living in Guatemala measured in 1998 (n = 1,347). Maya American children are currently 11.54 cm taller and 6.83 cm longer‐legged, on average, than Maya children living in Guatemala. Consequently, the Maya Americans have a significantly lower average sitting height ratio (i.e., relatively longer legs in proportion to length of the head and trunk) than do the Maya in Guatemala. These results add support to the hypothesis that both the height and body proportions of human populations are sensitive indicators of the quality of the environment for growth. Am. J. Hum. Biol. 14:753–761, 2002. © 2002 Wiley‐Liss, Inc. 相似文献