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排序方式: 共有1716条查询结果,搜索用时 36 毫秒
71.
Enzyme‐Responsive Nanoparticles for Targeted Accumulation and Prolonged Retention in Heart Tissue after Myocardial Infarction
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72.
Nathan Glazer 《Journal of the American Planning Association. American Planning Association》2013,79(4):191-196
The school today plays a peculiarly dynamic role in neighborhood change, for its quality-real or as perceived by parents-strongly affects the decisions of upper-income families as to where to live. If the school reflects the changing social composition of its immediate neighborhood, it tends to speed up the transition from upper-income to lower-income occupancy and to encourage social homogeneity and segregation. If it maintains special standards and a special approach toward education, independent of changes in the population of the surrounding area, it serves as a brake on population change and tends to encourage heterogeneous neighborhoods. It is suggested this principle may help in achieving stable and heterogeneous neighborhoods. 相似文献
73.
Dr. Pradeep K. Singh Hao Fan Xiuju Jiang Prof. Dr. Lei Shi Prof. Dr. Carl F. Nathan Prof. Dr. Gang Lin 《ChemMedChem》2016,11(19):2127-2131
N,C‐capped dipeptides belong to a class of noncovalent proteasome inhibitors. Herein we report that the insertion of a β‐amino acid into N,C‐capped dipeptides markedly decreases their inhibitory potency against human constitutive proteasome β5c, while maintaining potent inhibitory activity against human immunoproteasome β5i, thereby achieving thousands‐fold selectivity for β5i over β5c. Structure–activity relationship studies revealed that β5c does not tolerate the β‐amino acid based dipeptidomimetics as does β5i. In vitro, one such compound was found to inhibit human T cell proliferation. Compounds of this class may have potential as therapeutics for autoimmune and inflammatory diseases with less mechanism‐based cytotoxicity than agents that also inhibit the constitutive proteasome. 相似文献
74.
This paper studies the effect of the zone tax offset (ZTO), a place based income subsidy implemented in rural Australia since 1945. The policy was intended to improve the welfare of inhabitants and provide an incentive for settlement. Our empirical approach exploits the geographical discontinuity in the eligibility for the subsidy to identify its causal effect on population growth. Using data on population by locality from the historical censuses we find that the ZTO had a positive but only temporary effect on population growth in the targeted areas. 相似文献
75.
The cost and quality of an assembly depend on the processes used to manufacture its components. The specific processes and process settings are often dictated by the tolerances on the components. One long-standing challenge is allocating the assembly tolerance to components. Many methods have been proposed, most of which endeavor to minimize cost. We propose a tolerance allocation method that minimizes cost by jointly considering process variation and tolerance specifications. A cost model including processing cost, scrap cost, and quality loss is employed. The cost is minimized by a heuristic strategy. An overrunning clutch assembly case study is used to evaluate the method. 相似文献
76.
Crosslinking effect on polydimethylsiloxane elastic modulus measured by custom‐built compression instrument
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A macroscopic compression test utilizing a simple custom‐built instrument was employed to measure polydimethylsiloxane (PDMS) elastic modulus. PDMS samples with varying crosslinking density were prepared with the elastomer base to the curing agent ratio ranging from 5 : 1 to 33 : 1. The PDMS network elastic modulus varied linearly with the amount of crosslinker, ranging from 0.57 MPa to 3.7 MPa for the samples tested. PDMS elastic modulus in MPa can be expressed as 20 MPa/PDMS base to curing agent ratio. This article describes a simple method for measuring elastic properties of soft polymeric materials. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41050. 相似文献
77.
Xin Zhang Stphane Mlik-Parsadaniantz Christophe Baudouin Annabelle Raux-Le Goazigo Nathan Moreau 《International journal of molecular sciences》2022,23(7)
The cornea, an anterior ocular tissue that notably serves to protect the eye from external insults and refract light, requires constant epithelium renewal and efficient healing following injury to maintain ocular homeostasis. Although several key cell populations and molecular pathways implicated in corneal wound healing have already been thoroughly investigated, insufficient/impaired or excessive corneal wound healing remains a major clinical issue in ophthalmology, and new avenues of research are still needed to further improve corneal wound healing. Because of its implication in numerous cellular/tissular homeostatic processes and oxidative stress, there is growing evidence of the role of Hedgehog signaling pathway in physiological and pathological corneal wound healing. Reviewing current scientific evidence, Hedgehog signaling and its effectors participate in corneal wound healing mainly at the level of the corneal and limbal epithelium, where Sonic Hedgehog-mediated signaling promotes limbal stem cell proliferation and corneal epithelial cell proliferation and migration following corneal injury. Hedgehog signaling could also participate in corneal epithelial barrier homeostasis and in pathological corneal healing such as corneal injury-related neovascularization. By gaining a better understanding of the role of this double-edged sword in physiological and pathological corneal wound healing, fascinating new research avenues and therapeutic strategies will undoubtedly emerge. 相似文献
78.
QiLiang Chen Dae Ik Yi Josiah Nathan Joco Perez Monica Liu Steven D. Chang Meredith J. Barad Michael Lim Xiang Qian 《International journal of molecular sciences》2022,23(7)
Trigeminal neuralgia (TN) is a complex orofacial pain syndrome characterized by the paroxysmal onset of pain attacks in the trigeminal distribution. The underlying mechanism for this debilitating condition is still not clearly understood. Decades of basic and clinical evidence support the demyelination hypothesis, where demyelination along the trigeminal afferent pathway is a major driver for TN pathogenesis and pathophysiology. Such pathological demyelination can be triggered by physical compression of the trigeminal ganglion or another primary demyelinating disease, such as multiple sclerosis. Further examination of TN patients and animal models has revealed significant molecular changes, channelopathies, and electrophysiological abnormalities in the affected trigeminal nerve. Interestingly, recent electrophysiological recordings and advanced functional neuroimaging data have shed new light on the global structural changes and the altered connectivity in the central pain-related circuits in TN patients. The current article aims to review the latest findings on the pathophysiology of TN and cross-examining them with the current surgical and pharmacologic management for TN patients. Understanding the underlying biology of TN could help scientists and clinicians to identify novel targets and improve treatments for this complex, debilitating disease. 相似文献
79.
Nathan J. Muller 《International Journal of Network Management》1996,6(5):271-283
In OpenView, Hewlett-Packard has concentrated on creating a multivendor management platform for TCP/IP-based internets. This plays to the company's strengths in LAN management, where it has been a major player in the LAN protocol analyzer market since the early 1980s, and its expertise in TCP/IP, which the company had been using internally since the early 1980s. 相似文献
80.
Charles W. Bauschlicher Jr. Cameron J. Bodenschatz Dwight L. Myers Nathan S. Jacobson 《Journal of the American Ceramic Society》2020,103(10):5870-5880
Thermodynamic parameters are reported for gaseous hydroxides and oxyhydroxides of Al, Zr, and Y. The structures and vibrational frequencies are calculated using density functional theory with the B3LYP functional. This yields entropies at 298.15 K and heat capacities. The enthalpies are calculated from appropriate reactions and the CCSD(T) (Coupled Cluster, Singles, Doubles, and perturbative Triples) approach. The hydroxide groups are treated as hindered rotors for all species. The results are compared to the limited experimental and theoretical calculations for these species. Finally, the data are put into a database for a free-energy minimizer and the vapor pressures for each species are compared. 相似文献