富血小板血浆(p late let-rich p lasm a,PRP)是通过离心自体全血而得到的含高浓度血小板的血浆。PRP中含有高浓度生长因子,如:血小板源性生长因子(p late let-derived grow thfactor,PDGF)、转化生长因子-β(transform ing grow th fac...
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富血小板血浆(p late let-rich p lasm a,PRP)是通过离心自体全血而得到的含高浓度血小板的血浆。PRP中含有高浓度生长因子,如:血小板源性生长因子(p late let-derived grow thfactor,PDGF)、转化生长因子-β(transform ing grow th fac-tor-,βTGF-β)、类胰岛素生长因子(insu lin-like grow th fac-tor,IGF)、表皮生长因子(ep iderm a l grow th factor,EGF)和血管内皮细胞生长因子(vascu lar endothe lia l grow th factor,VEGF)等。经酶联免疫吸附试验证实,PRP中除IGF以外,[第一段]
Perhaps surprisingly, a number of Canadian jurisdictions have been at the cutting edge of legal exemptions from seizure or attachment processes for artworks on loan. Starting with the curious case of Hermitage treasur...
Perhaps surprisingly, a number of Canadian jurisdictions have been at the cutting edge of legal exemptions from seizure or attachment processes for artworks on loan. Starting with the curious case of Hermitage treasures displayed in Winnipeg in the mid-1970s and using other intriguing examples, this article traces the historical origins of Canadian legislation with particular regard to the international context. The current state of the law in Canada is summarized and compared to that of other international jurisdictions.
Zwicky's analysis of syntactic notions as possible candidates for "head," based on constituent-structure theory, is discussed in detail. This analysis is contrasted with the results gained form one provi...
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Zwicky's analysis of syntactic notions as possible candidates for "head," based on constituent-structure theory, is discussed in detail. This analysis is contrasted with the results gained form one provided in a dependency-based theory in which "head" is the name of a grammatical relation category. (Author/LMO)
Climate change has driven a global shift from fossil fuels to renewable energy sources. However, the inherent variability of renewable energy, influenced by temporal and climatic factors, presents significant challeng...
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Climate change has driven a global shift from fossil fuels to renewable energy sources. However, the inherent variability of renewable energy, influenced by temporal and climatic factors, presents significant challenges. Underground hydrogen storage offers a promising solution for retaining surplus energy. The complexity and heterogeneity of geological formations are difficult to accurately quantify, leading to large uncertainties in storage assessment results, and computation of forward modeling for large-scale sites is often time-consuming. This study introduced a numerical modeling framework incorporating the complex geological structures into the uncertainty analysis of formation porosity and permeability. We developed surrogate models to predict the hydrogen storage process using three machine learning (ML) algorithms: Extreme Gradient Boosting (XGBoost), Random Forest (RF), and Support Vector Regression (SVR). The study utilized the Sobol algorithm to examine the impact of variations in porosity and permeability on model output. This study applied and analyzed the numerical modeling framework at Wangjiawan in China. The findings indicated that the average final stability of hydrogen injection mass approximates 1800 tons, with the average production mass of hydrogen reaching approximately 950 tons. The XGBoost model demonstrated excellent predictive performance (R2 = 0.9679 and RMSE = 0.0318). Hydrogen production mass and rate are primarily influenced by the permeability of the formations, including injection and production wells during stable periods, while the impact of formation porosity is relatively minor. This study quickly and accurately predicts hydrogen storage processes under different geological parameters by employing ML algorithms. It also evaluates the importance of various geological parameters, providing crucial insights for effectively designing underground hydrogen storage facilities.
Information concerning the natural history of peptic ulcer disease commencing in childhood is limited. We have followed up 19 individuals in whom this diagnosis had been made in childhood 14–27 years previously. Stri...
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Information concerning the natural history of peptic ulcer disease commencing in childhood is limited. We have followed up 19 individuals in whom this diagnosis had been made in childhood 14–27 years previously. Strict diagnostic criteria were used. A high incidence of morbidity persisting into adult life was found. On investigation 9 (47%) had had a proven ulcer since entering adult life. Ten (53%) were no longer prone to recurring abdominal pain, but four of these had undergone vagotomy and pyloroplasty (three after the age of 21) for intractable symptoms. Thus, only six patients (31%) had made a lasting and spontaneous recovery. Serious complications had occurred at some time in the past in 10 cases (53%). Overt gastrointestinal bleeding had occurred in eight (42%), and this had been after the age of 18 years in three. Duodenal perforation occurred in one subject, and severe pyloric stenosis in another, both of whom were aged 21 years. One subject developed a penetrating duodenal ulcer at the age of 24 years. Seven (37%) had undergone surgery, and in two of these cases more than one operation had been performed. Fifty-eight percent of complications suffered and 89% of surgical operations performed involved patients of 21 years or older. These findings firmly reinforce the opinion that the disorder frequently persists into adult life. The impact of modern means of medical therapy, such as the H 2 receptor antagonists, has not yet been fully evaluated.
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