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排序方式: 共有1379条查询结果,搜索用时 15 毫秒
41.
Nehemiah T. Liu Andriy I. Batchinsky Leopoldo C. Cancio José Salinas 《Computers in biology and medicine》2013
This study focused on the impact of noise on the reliability of heart-rate variability and complexity (HRV, HRC) to discriminate between different trauma patients and to monitor individual patients. Life-saving interventions (LSIs) were chosen as an endpoint because performance of LSIs is a critical aspect of trauma patient care. Noise was modeled and simulated by modifying original R–R interval (RRI) sequences via decimation, concatenation, and division of RRIs, as well as R-wave detection using the electrocardiogram. Results showed that under increasing simulated noise, entropy and autocorrelation measures can still effectively discriminate between LSI and non-LSI patients and monitor individuals over time. 相似文献
42.
Kirstie J. Salinas Carey Y. L. Huh Jack H. Zeitoun Sunil P. Gandhi 《The Journal of neuroscience》2021,41(7):1470
The mammalian visual cortex contains multiple retinotopically defined areas that process distinct features of the visual scene. Little is known about what guides the functional differentiation of visual cortical areas during development. Recent studies in mice have revealed that visual input from the two eyes provides spatiotemporally distinct signals to primary visual cortex (V1), such that contralateral eye-dominated V1 neurons respond to higher spatial frequencies than ipsilateral eye-dominated neurons. To test whether binocular visual input drives the differentiation of visual cortical areas, we used two-photon calcium imaging to characterize the effects of juvenile monocular deprivation (MD) on the responses of neurons in V1 and two higher visual areas, LM (lateromedial) and PM (posteromedial). In adult mice of either sex, we find that MD prevents the emergence of distinct spatiotemporal tuning in V1, LM, and PM. We also find that, within each of these areas, MD reorganizes the distinct spatiotemporal tuning properties driven by the two eyes. Moreover, we find a relationship between speed tuning and ocular dominance in all three areas that MD preferentially disrupts in V1, but not in LM or PM. Together, these results reveal that balanced binocular vision during development is essential for driving the functional differentiation of visual cortical areas. The higher visual areas of mouse visual cortex may provide a useful platform for investigating the experience-dependent mechanisms that set up the specialized processing within neocortical areas during postnatal development.SIGNIFICANCE STATEMENT Little is known about the factors guiding the emergence of functionally distinct areas in the brain. Using in vivo Ca2+ imaging, we recorded visually evoked activity from cells in V1 and higher visual areas LM (lateromedial) and PM (posteromedial) of mice. Neurons in these areas normally display distinct spatiotemporal tuning properties. We found that depriving one eye of normal input during development prevents the functional differentiation of visual areas. Deprivation did not disrupt the degree of speed tuning, a property thought to emerge in higher visual areas. Thus, some properties of visual cortical neurons are shaped by binocular experience, while others are resistant. Our study uncovers the fundamental role of binocular experience in the formation of distinct areas in visual cortex. 相似文献
43.
V.V. de Souza P.A.M. Vitale F.H. Florenzano R.K. Salinas I.M. Cuccovia 《Brazilian journal of medical and biological research》2021,54(5)
Amphiphilic copolymers have a wide variety of medical and biotechnological applications, including DNA transfection in eukaryotic cells. Still, no polymer-primed transfection of prokaryotic cells has been described. The reversible addition-fragmentation chain transfer (RAFT) polymer synthesis technique and the reversible deactivation radical polymerization variants allow the design of polymers with well-controlled molar mass, morphology, and hydrophilicity/hydrophobicity ratios. RAFT was used to synthesize two amphiphilic copolymers containing different ratios of the amphiphilic poly[2-(dimethyl-amino) ethyl methacrylate] and the hydrophobic poly [methyl methacrylate]. These copolymers bound to pUC-19 DNA and successfully transfected non-competent Escherichia coli DH5α, with transformation efficiency in the range of 103 colony-forming units per µg of plasmid DNA. These results demonstrate prokaryote transformation using polymers with controlled amphiphilic/hydrophobic ratios. 相似文献
44.
Carmen Díaz Galindo Beatriz Gómez-González Eva Salinas Denisse Calderón-Vallejo Irma Hernández-Jasso Eduardo Bautista J Luis Quintanar 《中国神经再生研究》2015,10(11):1819-1824
Gonadotropin-releasing hormone (GnRH) and its synthetic analog leuprolide acetate, a GnRH agonist, have neurotrophic properties. This study was designed to determine whether administration of leuprolide acetate can improve locomotor behavior, gait, micturition reflex, spinal cord morphology and the amount of microglia in the lesion epicenter after spinal cord injury in rats. Rats with spinal cord compression injury were administered leuprolide acetate or saline solution for 5 weeks. At the 5th week, leuprolide acetate-treated rats showed locomotor activity recovery by 38%, had improvement in kinematic gait and exhibited voiding reflex recovery by 60%, as compared with the 1st week. By contrast, saline solution-treated rats showed locomotor activity recovery only by 7%, but voiding reflex did not recover. More importantly, leuprolide acetate treatment reduced microglial immunological reaction and induced a trend towards greater area of white and gray matter in the spinal cord. Therefore, leuprolide acetate has great potential to repair spinal cord injury. 相似文献
45.
Lineage-restricted regulation of the murine SCL/TAL-1 promoter 总被引:10,自引:2,他引:10
Bockamp EO; McLaughlin F; Murrell AM; Gottgens B; Robb L; Begley CG; Green AR 《Blood》1995,86(4):1502-1514
46.
47.
Laura Villarreal‐Martínez Jaime García‐Chvez Berenice Snchez‐Jara Aida Mashenka Moreno‐Gonzlez Janet Soto‐Padilla Efraín Aquino‐Fernndez Rogelio Paredes‐Aguilera Karla Maldonado‐Silva Cecilia Rodríguez‐Castillejos Ana Itamar Gonzlez‐vila María Mora‐Torres Hector Manuel Tiznado‐García Natalia Elizabeth Padilla‐Durn Nuria Citlali Luna‐Silva Eric Israel Gutirrez‐Jurez Jorge Nemi‐Cueto Claudia Sofia Gmez‐Gonzlez Ricardo De Len‐Figueroa Adela Lpez‐Miranda Mirna Guadalupe Ríos‐Osuna Edna Liliana Tamez‐Gmez Elio Aarn Reyes‐Espinoza Irving Armando Domínguez‐Varela Gerardo Gonzlez‐Martínez Elias Adn Godoy‐Salinas 《Haemophilia》2020,26(2):290-297
48.
Buddula A Assad DA Salinas TJ Garces YI Volz JE Weaver AL 《Clinical implant dentistry and related research》2012,14(5):716-722
Purpose: To study the long‐term survival of dental implants placed in irradiated bone in subjects who received radiation for head and neck cancer. Materials and Method: A retrospective chart review was conducted for all patients who received dental implants following radiation treatment for head and neck cancer between May 1, 1987 through July 1, 2008. Only patients irradiated with a radiation dose of 50 Gy or greater and those who received dental implants in the irradiated field after head and neck radiation were included in the study. The associations between implant survival and patient/implant characteristics were estimated by fitting univariate marginal Cox proportional hazards models. Results: A total of 48 patients who had prior head and neck radiation had 271 dental implants placed during May 1987 to July 2008. The estimated survival at 1, 5, and 10 years was 98.9%, 89.9%, and 72.3%, respectively. Implants placed in the maxilla were more likely to fail than implants placed in the mandible (p = .002).There was also a tendency for implants placed in the posterior region to fail compared with those placed in the anterior region (p = .051). Conclusion: Dental implants placed in irradiated bone have a greater risk for failure. Survival is significantly influenced by the location of the implant (maxilla or mandible, anterior or posterior). 相似文献
49.
Harry Salinas Abdulmentin Dursun Ioannis Konstantinidis Deanna Nguyen Paul Shellito Richard Hodin Liliana Bordeianou 《International journal of colorectal disease》2012,27(11):1479-1483
Purpose
Malnutrition is a frequent problem in patients with ulcerative colitis (UC) leading to increased postoperative complication rates. Preoperative total parenteral nutrition (TPN) has been shown to reduce complications in some subgroups of patients, but has not been studied in UC. We investigated the impact of preoperative TPN on postoperative complication rates in patients undergoing surgery for UC.Methods
This paper is a review of 235 patients who underwent surgery for UC; 56 received preoperative TPN and 179 did not. Postoperative complication rates were compared.Results
Both had similar rates of anastomotic leak (5.4 vs. 2.8?%, p?=?0.356), infection (12.5 vs. 20.1?%, p?=?0.199), ileus/bowel obstruction (21.4 vs. 15.6?%, p?=?0.315), cardiac complications (3.6 vs. 0?%, p?=?0.056), wound dehiscence (3.6 vs. 1.7?%, p?=?0.595), reoperation (10.7 vs. 3.9?%, p?=?0.086), and death (1.8 vs. 0?%, p?=?0.238). The TPN group was more malnourished (albumin 2.49 vs. 3.45, p?<?0.001), more often on steroids (83.9 vs. 57.5?%, p?<?0.001), had more emergent surgery (10.7 vs. 3.4?%, p?=?0.029), more severe colitis (89.3 vs. 65.9?%, p?=?0.001), and lower Surgical Apgar Score (6.15 vs. 6.57, p?=?0.033). After controlling for these with logistic regression, the TPN group still had higher complication rates (OR 2.32, p?=?0.04). When line infections were excluded, TPN did not significantly affect outcomes (OR 1.5, p?=?0.311)Conclusion
There were no differences in postoperative complications when line infections were excluded. Our data does not support routine preoperative TPN in patients with UC. However, it may lead to equal surgical outcomes in the sickest and most malnourished patients at the cost of line-related morbidity. 相似文献50.
PO Ajiboye OA Abiodun MF Tunde-Ayinmode OIN Buhari EO Sanya KW Wahab 《African health sciences》2013,13(3):624-631