Publications by authors named "Shimei He"

Objective: This study sought to compare the risks and outcomes associated with category I cesarean section procedures performed in the delivery room versus those performed in the operating room.

Patients And Methods: The analysis included 126 singleton pregnant women who underwent inpatient delivery at the Second People's Hospital of Nanning between January 2021 and May 2024. Following propensity score matching, 21 cases were in the delivery room group, and 105 cases were in the operating room group.

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An ammonium ylide-based relay annulation was disclosed, which uses DABCO as the catalyst and oxindole-derived α,β-unsaturated ketimines and γ-bromo-crotonates as the starting materials. This method enables the rapid assembly of a series of structurally novel spiro-polycyclic oxindoles containing a bicyclo[4.1.

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The exploitation of new reactive species and novel transformation modes for their synthetic applications have significantly promoted the development of synthetic organic methodology, drug discovery, and advanced functional materials. α-Iminyl radical cations, a class of distonic ions, exhibit great synthetic potential for the synthesis of valuable molecules. For their generation, radical conjugate addition to α,β-unsaturated iminium ions represents a concise yet highly challenging route, because the generated species are short-lived and highly reactive and they have a high tendency to cause radical elimination (β-scission) to regenerate the more stable iminium ions.

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A metal-free three-component protocol that combines a hydroxylamine-Passerini reaction and hetero-Cope rearrangement was realized, which enables the modular assembly of a wide range of structurally new and interesting 2-aminoanilines bearing an α-hydroxyamide substructure.

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Collapsibility and structural are two of the typical characteristics of natural undisturbed loess. It is of great significance to effectively simulate the collapsibility and structural of natural loess by preparing artificially loess. However, the existing methods of artificially preparing collapsible loess are complex, and the collapsibility of the prepared samples is difficult to control.

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In the presence of CuOAc, a series of unsymmetric ureas can be generated in moderate to good yields under mild reaction conditions (10 mol% of CuOAc, 2 equiv -BuONa or PhONa, 30 °C), using aryl isocyanides and -benzoyl hydroxylamines as the readily accessible starting materials. The reactions might undergo a cascade process involving isocyanide insertion into the N-O bond and Mumm-type rearrangement. This work represents a rare example of isocyanide insertion into N-O bonds, which would extend isocyanide insertion chemistry.

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