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91.
Although vision is considered the dominant modality, recent studies demonstrate the influence of other modalities on visual perception. For example, in the sound-induced flash illusion, two auditory stimuli cause one visual flash to be perceived as two. We report an extension of the sound-induced flash illusion to the tactile-visual domain, yielding the touch-induced flash illusion. Observers reported seeing two flashes on the majority of trials when a single flash was presented concurrently with two task-irrelevant brief tactile stimuli. Somatosensory stimulation changed the sensitivity (d') of detecting visual stimuli, which suggests that the observed effect is at least partly due to perceptual interactions. Together with other recent findings, these results challenge the notion that the processing of visual information is independent of activity in other modalities. 相似文献
92.
Matrix metalloproteases: degradation of the inhibitory environment of the transected optic nerve and the scar by regenerating axons 总被引:5,自引:0,他引:5
Ahmed Z Dent RG Leadbeater WE Smith C Berry M Logan A 《Molecular and cellular neurosciences》2005,28(1):64-78
After injury to the central nervous system, a glial/collagen scar forms at the lesion site, which is thought to act as a physicochemical barrier to regenerating axons. We have shown that scar formation in the transected optic nerve (ON) is attenuated when robust growth of axons is stimulated. Matrix metalloproteases (MMP), modulated by tissue inhibitors of MMP (TIMP), degrade a wide variety of extracellular matrix components (ECM) and may be activated by growing axons to remodel the ECM to allow regeneration through the inhibitory environment of the glial or collagen scar. Here, we investigate whether MMP levels are modulated in a nonregenerating (scarring) versus a regenerating (nonscarring) model of ON injury in vivo. Western blotting and immunohistochemistry revealed that MMP-1, -2, and -9 levels were higher and TIMP-1 and TIMP-2 levels were lower in regenerating compared to nonregenerating ON and retinae. In situ zymography demonstrated significantly greater MMP-related gelatinase activity in the regenerating model, mainly colocalized to astrocytes in the proximal ON stump and around the lesion site. These results suggest that activation of MMP and coincident down-regulation of TIMP may act to attenuate the inhibitory scarring in the regenerating ON, thus transforming the ON into a noninhibitory pathway for axon regrowth. 相似文献
93.
Parathyroid lesions, which may occur within the thyroid, may clinically simulate thyroid nodules. Fine-needle aspiration (FNA) of these presumably "thyroid nodules" can lead to misinterpretation of cytomorphological findings because of similarities in cytological features of neoplastic and nonneoplastic parathyroid and thyroid lesions. This might be true especially for oncocytic parathyroid adenomas and parathyroid adenomas with prominent oncocytic component that, although rare, tend to be large and often are associated with minimal hyperparathyroidism. We report two cases of this type of clinically "silent" parathyroid adenomas that on FNA were diagnosed as Hurthle cell thyroid neoplasm. 相似文献
94.
Morbidity following central compartment reoperation for recurrent or persistent thyroid cancer 总被引:5,自引:0,他引:5
Kim MK Mandel SH Baloch Z Livolsi VA Langer JE Didonato L Fish S Weber RS 《Archives of otolaryngology--head & neck surgery》2004,130(10):1214-1216
OBJECTIVE: To determine the incidence of recurrent laryngeal nerve injury and hypoparathyroidism, we reviewed our experience with central compartment reoperation. DESIGN: Patients underwent preoperative ultrasonography and magnetic resonance imaging of the neck. Ultrasound-guided fine-needle aspiration biopsy was performed and demonstrated evidence of tumor in 15 patients. At the time of surgery, hook wire electrodes were placed endoscopically into 1 or both vocal cords to monitor the integrity of the recurrent laryngeal nerve. PATIENTS: The study population comprised 20 patients who had undergone reoperative central compartment dissections between the years 1997 and 2001. There were 15 women and 5 men whose mean age was 49.4 years. All of the patients had prior total or subtotal thyroidectomy, and 4 patients had prior neck dissections. A primary thyroid cancer recurrence in the thyroid bed was present in 7 patients, and the remainder of the patients had cytological evidence of paratracheal or mediastinal metastases. A single patient had evidence of distant metastases involving the lung. MAIN OUTCOME MEASURE: Short- and long-term postoperative morbidity. RESULTS: Of the 20 patients, 18 had histologic evidence of metastases to the paratracheal lymph nodes, whereas 8 patients had metastases involving the anterior mediastinal lymph nodes. The mean number of lymph nodes removed was 6.5, and the mean number of positive lymph nodes was 4.7. None of the patients with normal preoperative laryngeal function had postoperative recurrent laryngeal nerve paresis or paralysis. There were 18 patients with normal preoperative parathyroid function. Four patients developed transient postoperative hypocalcemia. All 4 patients with transient postoperative hypocalcemia are currently eucalcemic. A single patient continues to receive calcium and calcitriol supplementation 1 month following her third central compartment dissection for recurrent thyroid cancer. CONCLUSIONS: Reoperation for recurrent or persistent thyroid cancer presents a significant challenge. However, intraoperative recurrent laryngeal nerve monitoring and preservation of the vascular pedicle of the parathyroid glands has reduced the morbidity of reoperative central compartment dissections to acceptable levels. Revision surgery in the central compartment of the neck is compatible with successful eradication of recurrent thyroid cancers and acceptable morbidity. 相似文献
95.
Background
This study was designed to examine the knowledge, attitude and beliefs about causes, manifestations and treatment of mental illness among adults in a rural community in northern Nigeria. 相似文献96.
Abbasi MA Ahmad VU Zubair M Fatima N Farooq U Hussain S Lodhi MA Choudhary MI 《Planta medica》2004,70(12):1189-1194
A re-investigation of the chemical constituents of the stem bark of Symplocos racemosa Roxb. led to the isolation of four new glycosides, symplocomoside (1), symponoside (2), symplososide (3) and symploveroside (4). Benzoylsalireposide (5) and salireposide (6) were re-isolated from this plant. The structures of the new compounds were determined by 1D and 2D-homonuclear and heteronuclear NMR spectroscopy, chemical evidence, and by comparison with the published data of the closely related compounds. The glycosides 1-4 displayed in vitro inhibitory activity against phosphodiesterase I with IC50 values of 122 +/- 0.017, 698 +/- 0.06, 722 +/- 0.03, 909 +/- 0.09 microM, respectively. The compounds 1-6 also showed in vitro inhibitory activity against thymidine phosphorylase with IC50 values of 189.96 +/- 1.02, 195.56 +/- 2.36, 207.61 +/- 1.06, 488.89 +/- 4.10, 427.20 +/- 5.36, 354.2 +/- 5.69 microM, respectively while 1 was also found to be a urease inhibitor with an IC50 value of 54.13 +/- 0.71 microM. 相似文献
97.
98.
Kabir Z Long J Reddaiah VP Kevany J Kapoor SK 《Bulletin of the World Health Organization》2003,81(4):244-250
OBJECTIVE: To determine whether vaccination against measles in a population with sustained high vaccination coverage and relatively low child mortality reduces overall child mortality. METHODS: In April and May 2000, a population-based, case-control study was conducted at Ballabgarh (an area in rural northern India). Eligible cases were 330 children born between 1 January 1991 and 31 December 1998 who died aged 12-59 months. A programme was used to match 320 controls for age, sex, family size, and area of residence from a birth cohort of 15 578 born during the same time period. FINDINGS: The analysis used 318 matched pairs and suggested that children aged 12-59 months who did not receive measles vaccination in infancy were three times more likely to die than those vaccinated against measles. Children from lower caste households who were not vaccinated in infancy had the highest risk of mortality (odds ratio, 8.9). A 27% increase in child mortality was attributable to failure to vaccinate against measles in the study population. CONCLUSION: Measles vaccine seems to have a non-specific reducing effect on overall child mortality in this population. If true, children in lower castes may reap the greatest gains in survival. The findings should be interpreted with caution because the nutritional status of the children was not recorded and may be a residual confounder. "All-cause mortality" is a potentially useful epidemiological endpoint for future vaccine trials. 相似文献
99.
Hyder AA Arifeen S Begum N Fishman S Wali S Baqui AH 《Injury control and safety promotion》2003,10(4):205-210
The study focuses on children less than 5 years old and explores the epidemiological profile and correlates of drowning as a challenge to child survival in Bangladesh. Two data sources from Bangladesh, a cohort of 8,070 children followed for 2 years in a rural area and a nation-wide survey conducted in 1996-97 have been used. In addition, a systematic review of the literature has been conducted spanning the past two decades for analysis of drowning in children. Seventy drowning deaths were reported in the cohort and 726 deaths were reported in the national survey. Verbal autopsy and semi-structured interviews were conducted on all deaths. Drowning accounted for 43% of deaths in the cohort and 20% of deaths in 1-4-year-old children in the national survey. Most drowning deaths were in 12-23 month old children from falling into ditches and ponds. Communities provided valuable insights on possible interventions to reduce deaths due to drowning. Drowning is a newly recognized challenge for Bangladesh. Considerable research and programmatic work is required to understand the nature of the problem and develop appropriate interventions. This paper calls on aid agencies to create opportunities for drowning research and action in their work plans for the country. 相似文献
100.