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41.
In this work, a fast digital device is defined, which is customized to implement an artificial neuron. Its high computational speed is obtained by mapping data from floating point to integer residue representation, and by computing neuron functions through residue arithmetic operations, with the use of table look-up techniques. Specifically, the logic design of a residue neuron is described and complexity figures of area occupancy and time consumption of the proposed device are derived. The approach was applied to the logic design of a residue neuron with 12 inputs and with a Residue Number System defined in such a way as to attain an accuracy better than or equal to the accuracy of a 20-bit floating point system. The proposed design (NEUROM) exploits the RNS carry independence property to speed up computations, in addition it is very suitable for using look-up tables. The response time of our device is about 8 x T(ACC), where T(ACC) is the ROM access time. With a value of T(ACC) close to the 10 ns allowed by the current ROM technology, the proposed neuron responds within 80 ns, NEUROM is therefore the neuron device proposed in the literature which allows for maximum throughput. Moreover, when a pipeline mode of operation is adopted, the pipeline delay can assume a value as low as about 14 ns. In the case study considered, the total amount of ROM is about 5.55 Mbits. Thus, using current technology, it is possible to integrate several residue neurons into a single VLSI chip, thereby enhancing chip throughput. The paper also discusses how this amount of memory could be reduced, at the expense of the response time. 相似文献
42.
Tooth autotransplantation as a pillar for 3D regeneration of the alveolar process after severe traumatic injury: A case report
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Eduardo Anitua Maialen Mendinueva‐Urkia Sandra Galan‐Bringas Alia Murias‐Freijo Mohammad Hamdan Alkhraisat 《Dental traumatology》2017,33(5):414-419
In dental traumatology, the loss of teeth and the supporting alveolar bone in children compromise the proper development of maxillofacial structures and also limit the solutions that can be offered. In this case report, multidisciplinary management is described of a child with a significant loss of alveolar bone and associated teeth due to a traffic accident at 8 years of age. The management involved staged teeth autotransplantation into surgically prepared sites with bone expanders, orthodontic treatment and dental implants. The 3D regeneration of the alveolar process was successfully stimulated by teeth autotransplantation. At the 4‐year follow‐up visit, evaluation of the autotransplanted teeth and the implants indicated a successful outcome for the patient. 相似文献
43.
Intrathecal enzyme replacement therapy reverses cognitive decline in mucopolysaccharidosis type I
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Igor Nestrasil Elsa Shapiro Alena Svatkova Patricia Dickson Agnes Chen Amy Wakumoto Alia Ahmed Edward Stehel Sarah McNeil Curtis Gravance Elizabeth Maher 《American journal of medical genetics. Part A》2017,173(3):780-783
Mucopolysaccharidosis type I (MPS I) is an inherited lysosomal storage disease that seriously affects the brain. Severity of neurocognitive symptoms in attenuated MPS subtype (MPS IA) broadly varies partially, due to restricted permeability of blood‐brain barrier (BBB) which limits treatment effects of intravenously applied α‐L‐iduronidase (rhIDU) enzyme. Intrathecal (IT) rhIDU application as a possible solution to circumvent BBB improved brain outcomes in canine models; therefore, our study quantifies effects of IT rhIDU on brain structure and function in an MPS IA patient with previous progressive cognitive decline. Neuropsychological testing and MRIs were performed twice prior (baseline, at 1 year) and twice after initiating IT rhIDU (at 2nd and 3rd years). The difference between pre‐ and post‐treatment means was evaluated as a percentage of the change. Neurocognitive performance improved particularly in memory tests and resulted in improved school performance after IT rhIDU treatment. White matter (WM) integrity improved together with an increase of WM and corpus callosum volumes. Hippocampal and gray matter volume decreased which may either parallel reduction of glycosaminoglycan storage or reflect typical longitudinal brain changes in early adulthood. In conclusion, our outcomes suggest neurological benefits of IT rhIDU compared to the intravenous administration on brain structure and function in a single MPS IA patient. © 2017 The Authors. American Journal of Medical Genetics Part A Published by Wiley Periodicals, Inc. 相似文献
44.
Roque M Kim WJ Gazdoin M Malik A Reis ED Fallon JT Badimon JJ Charo IF Taubman MB 《Arteriosclerosis, thrombosis, and vascular biology》2002,22(4):554-559
Monocyte chemoattractant protein (MCP)-1 is upregulated in atherosclerotic plaques and in the media and intima of injured arteries. CC chemokine receptor 2 (CCR2) is the only known functional receptor for MCP-1. Mice deficient in MCP-1 or CCR2 have marked reductions in atherosclerosis. This study examines the effect of CCR2 deficiency in a murine model of femoral arterial injury. Four weeks after injury, arteries from CCR2(-/-) mice showed a 61.4% reduction (P<0.01) in intimal area and a 62% reduction (P<0.05) in intima/media ratio when compared with CCR2(+/+) littermates. The response of CCR2(+/-) mice was not significantly different from that of CCR2(+/+) mice. Five days after injury, the medial proliferation index, determined by bromodeoxyuridine incorporation, was decreased by 59.8% in CCR2(-/-) mice when compared with CCR2(+/+) littermates (P<0.05). Although leukocytes rapidly adhered to the injured arterial surface, there was no significant macrophage infiltration in the arterial wall of either CCR2(-/-) or CCR2(+/+) mice 5 and 28 days after injury. These results demonstrate that CCR2 plays an important role in mediating smooth muscle cell proliferation and intimal hyperplasia in a non-hyperlipidemic model of acute arterial injury. CCR2 may thus be an important target for inhibiting the response to acute arterial injury. 相似文献
45.
Alia Ayatollahi Mousavi A. R. Saied Ehsan Heidari 《Archives of orthopaedic and trauma surgery》2012,132(11):1555-1559
Background
Limb loss occurs as a result of different causes and has been increasing in many countries. This study determines the demography of amputees in one of the relatively large cities of Iran.Methods
This retrospective study was undertaken on all of the amputees between 2003 and 2011. Patients’ demographics including age, sex, the limb that had undergone amputation, etiology of limb loss and side and level of amputation were recorded. Also, the level of amputation was recorded as minor (below wrist or ankle) or major (above wrist or ankle).Results
In total, 624 patients were enrolled in the study. The number of amputees was from 53 to 118/year. Of the patients, 508 were male (81.4?%) and 118 were female (18.6?%). The men with amputation were younger on average than women; 61.9?% of the amputations (386) were major and 38.1?% were minor (238). Overall, the most common cause of amputation was trauma and the most common level was transmetatarsal. The most common level for major amputations was below knee.Conclusion
In contrast to similar studies in developed countries, trauma was found to be the major cause of all types of amputations and in all age groups, which emphasizes the need for preventive measures in the country. 相似文献46.
47.
Trojjet S Hammami H Zaraa I Bouzguarrou A Joens M Haouet S Ben Osman A Mokni M 《Skinmed》2012,10(1):50-52
A 70-year-old woman presented with an atypical erythematopapular zosteriform eruption of 3 weeks' duration. The patient had no history of previous vesicular eruption. She developed a painful burning sensation on the neck. Clinical examination revealed a cluster of small erythematous firm papules and plaques in a zosteriform distribution on the left ear, face, neck, and shoulder (Figure 1A). The lesions were unilateral and did not cross the midline. Multiple cervical and axillary lymph nodes were palpable. Laboratory tests revealed an increase in white blood cells of 25,000/mm3, with 17,910/mm3 lymphocytes and a normal range of hemoglobin, platelets, creatinine, and liver enzymes. Erythrocyte sedimentation rate was 87 mm. Blood smear results showed small, morphologically mature lymphocyte cells. In immune phenotyping, lymphocyte cells co-express CD5 and B-cell-surface antigens CD19 and CD23, as well as a restriction of kappa immunoglobulin light chains. The cells were CD22-, CD79b-, CD38-, CD10-, CD25- and FMC7-. Computed thoracoabominal tomography revealed cervical, mediastinal, abdominal, and pelvic adenopathy confirming the diagnosis of B-cell chronic lymphocytic leukemia (B-CLL) stage B. Histology of a skin biopsy from a papule showed a dense nodular granulomatous infiltrate in the dermis (Figure 2A). The infiltrate contained epithelioid and giant cells surrounded by lymphocytes and plasma cells. Small monomorphic lymphocytes without mitotic figures predominated (Figure 2B). The epidermis was irregularly thickened. Immunohistology revealed a polymorphous infiltrate with a phenotype of reactive T lymphocytes (CD3, CD5 positive) (Figure 2C), B lymphocytes (CD20 positive) (Figure 2D). Epithelioid and giant cells were positive for CD68 (Figure 2E). A latent herpes zoster infection with granulomatous reaction at the site ofzoster lesions was highly suspected as the patient reported a unilateral burning sensation without a history of vesicular zosteriform eruption. She received treatment with intravenous acyclovir 10 mg/kg every 8 hours. The papular lesions resolved markedly (60%) on macular plaques at the end of the treatment. Following topical treatment with corticosteroids, the lesions healed completely within 4 weeks (Figure 1B). Concerning leukemia, our patient was monitored without therapy by the hematologist. 相似文献
48.
Frank K. Friedenberg Alia Dadabhai Amiya Palit Abhinav Sankineni 《Quality of life research》2012,21(10):1713-1717
Purpose
To quantify the impact of constipation on health-related quality of life (HRQoL) in Black Americans.Methods
Case?Ccontrol design. Black subjects referred for colon cancer screening with a Bristol Stool Score of 3?C5 for >75% of bowel movements served as controls. Frequency-matched functional constipation subjects had to fulfill Rome III criteria. Both groups completed demographic and health surveys. Short Form-36 assessed HRQoL.Results
We recruited 102 constipated patients and 100 controls. The groups were well matched demographically. After adjustment for comorbidities, SF-36 scores for vitality, bodily pain, social functioning, and role-emotional were significantly lower in constipated patients. Unadjusted physical and mental component summary scores (PCS and MCS) were significantly higher in the control group (47.1?±?10.6 vs. 43.3?±?8.6; P?=?0.005 and 50.6?±?12.4 vs. 43.4?±?11.8; P?<?0.001, respectively). After adjustment for comorbidities, PCS differences were no longer significant (P?=?0.54); however, MCS differences were significant (P?=?0.004). Marginal mean scores for the MCS for controls and constipated subjects were 49.9?±?1.2 and 43.6?±?1.2, respectively. The presence of a comorbidity was independently associated with PCS (P?<?0.001) and MCS (P?=?0.026) results.Conclusions
Functional constipation has a significant impact on HRQoL in middle-aged Black Americans, particularly in regard to mental well-being. 相似文献49.
50.
Turner CF Villarroel MA Rogers SM Eggleston E Ganapathi L Roman AM Al-Tayyib A 《Addiction (Abingdon, England)》2005,100(10):1432-1444
AIM: To assess the impact of telephone audio computer-assisted self-interviewing (T-ACASI) on reporting of alcohol use, alcohol problems and illicit drug use in telephone surveys of the general population. Prior research suggests that illicit drug use is underreported in traditional, interviewer-administered, telephone surveys. DESIGN: Randomized experiment embedded in telephone survey of probability samples of populations of USA and Baltimore, MD. Survey respondents were randomly assigned to be interviewed either by human telephone interviewers or by T-ACASI after household screening, recruitment, and informed consent procedures were completed. SETTING: Respondents were interviewed by telephone in their homes. PARTICIPANTS: Probability samples of 1543 English-speaking adults ages 18-45 residing in telephone-accessible households in USA and 744 similarly defined adults residing in Baltimore, MD, USA. MEASUREMENTS: Nine questions on alcohol, marijuana, cocaine, and injection drug use adapted from 1994 NHSDA and four CAGE questions on alcohol problems. Crude odds ratios and odds ratios controlling for demographic factors calculated to test for differences between responses obtained by T-ACASI and human interviewers. FINDINGS: T-ACASI had mixed effects on reporting of alcohol use, but it did increase reporting of one of four CAGE alcohol problems: feeling guilty about drinking (23.0% in T-ACASI vs. 17.6% in T-IAQ, OR = 1.4, P < 0.01). T-ACASI also obtained significantly more frequent reporting of marijuana, cocaine, and injection drug use. The impact of T-ACASI was most pronounced for reporting of recent use of 'harder' drugs. Thus T-ACASI respondents were more likely to report marijuana use in the past month (10.0% vs. 5.7%, crude OR = 1.9, P < 0.001), cocaine use in the past month (2.1% vs. 0.7%, crude 3.2, P < 0.001) and injection drug use in the past five years (1.6% vs. 0.3%, crude OR = 4.8, P < 0.01). CONCLUSIONS: Telephone survey respondents were more likely to report illicit drug use and one alcohol problem when interviewed by T-ACASI rather than by human telephone interviews. 相似文献