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1.
Front Pharmacol ; 15: 1363071, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659575

RESUMO

Common bile duct stones, as a type of cholelithiasis, are a benign biliary obstruction that easily acute abdominalgia, and Endoscopic Retrograde Cholangiopancreatography (ERCP) is usually the first choice for clinical treatment. However, the increasing recurrence rate of patients after treatment is troubling clinicians and patients. For the prevention of recurrence after ERCP, there is no guideline to provide a clear drug regimen, traditional Chinese medicine however has achieved some result in the treatment of liver-related diseases based on the "gut-liver-bile acid axis". On the basis of this, this article discusses the possibility of traditional Chinese medicine to prevent common bile duct stones (CBDS) after ERCP, and we expect that this article will provide new ideas for the prevention of recurrence of CBDS and for the treatment of cholelithiasis-related diseases with traditional Chinese medicine in future clinical and scientific research.

2.
J Hand Surg Am ; 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35940998

RESUMO

PURPOSE: The length change of the interosseous membrane (IOM) during forearm rotation has not been fully studied. To explore the meaning of length change in the distal oblique band (DOB), the distal accessory band (DAB), and the proximal, middle, and distal parts of the central band (CBP, CBM, and CBD, respectively), we investigated the length change in these ligaments at maximum pronation, 45° of pronation, neutral position, 45° of supination, and maximum supination in vivo. METHODS: The images of the right forearms from 6 healthy volunteers were obtained by computed tomography scanning at the 5 above-mentioned rotation positions. We created 3-dimensional models of the radius and ulna, DOB, DAB, and central band based on the points of origin and insertion. Finally, the length of each ligament was estimated from the points of insertions and origins registered on the 3-dimensional models. RESULTS: The DAB and CBD lengths increased significantly from maximum pronation to 45° of pronation. The DOB length increased significantly from 45° of pronation to neutral position and decreased significantly from 45° of supination to maximum supination. The DAB and CBM lengths increased significantly from neutral position to 45° of supination. The DAB length decreased significantly from 45° of supination to maximum supination. For the CBP, no difference in length was observed during forearm rotation. CONCLUSIONS: The DOB becomes taut at neutral position, and the central band, especially the CBP, is nearly isometric. The findings indicate that the DOB may provide the primary stabilization of the distal radioulnar joint and that the central band is the key stabilizer during forearm rotation. CLINICAL RELEVANCE: Surgeons may pay attention to the DOB when a patient incurs a distal radioulnar joint injury, and the CBP may be the optimal location for IOM reconstruction.

3.
J Acoust Soc Am ; 151(5): 3387, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35649941

RESUMO

The Gaussian beam tracing method has advantages in computing long-distance noise propagation in outdoor environments due to its high efficiency. Usually, repeated computations are required if the target sound wave is broadband or contains multiple frequencies because the method was developed in the frequency domain. This paper presents an efficient computation of broadband noise propagation using Gaussian beam tracing. The approach is based on the fact that the ray behaviors and source properties can be decoupled at high frequencies, where the wave equation is asymptotically solved. Consequently, only a single computation is needed to determine the frequency-independent ray properties, including ray-centered coordinates and beam dynamics. Then sound waves at different frequencies can be simultaneously introduced in a single computation. By separating the processes of determining the ray properties and incorporating the broadband noise source in the numerical implementation, the computational cost can be largely saved. In this work, several benchmark problems are studied, showing that the efficiency could be increased in comparison to the multiple individual computations. A computation acceleration up to 35-fold could be achieved when 200 frequency components are applied. The method is also applied to study the impact of broadband noise due to multiple drone propellers in urban environments. Applications to stochastic broadband problems are also discussed.

4.
J Acoust Soc Am ; 149(4): 2743, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33940903

RESUMO

For large-distance sound propagation with complex obstacles, the Gaussian beam tracing (GBT) method is often applied. An omnidirectional source model is commonly implemented in GBT, which, however, neglects the influence of generic directivity patterns of practical acoustic problems. There have been efforts to synthesize or reproduce the target directivity pattern over an observation surface by using multiple distributed point sources. However, the efficiency and applicability of general applications still call for improvement. More specifically, rays from each of the point sources and their traces in the space should be computed and superposed to estimate the sound field, making the computational cost largely dependent on the complexity of the source directivity pattern. In this work, a complex-valued radiation function model is developed to realize the generic source directivity for GBT computation. One advantage of the method is that only one source is required such that computation cost can be greatly reduced. Rays are emitted from the source with direction-dependent amplitude and phase to realize the target directivity pattern. The development of the radiation function is associated with the GBT method. The verification cases show that this method can give good agreement with analytical or wave-based numerical solutions. Capabilities of modeling a complex source model of the spinning sound field to mimic the propeller noise are studied, and the result matches well with analytical solutions. Finally, a demonstration case of a four-propeller-powered drone in an urban region is conducted.

6.
J Shoulder Elbow Surg ; 30(6): 1238-1244, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32950672

RESUMO

OBJECTIVE: To evaluate the contact area of the radiocapitellar joint with forearm pronation and supination under axial loading. MATERIALS AND METHODS: Six healthy volunteers (2 males and 4 females, mean age: 44.6 years) were included in the study. A computed tomography scan of the extended elbow joints was obtained at 4 positions of forearm: full pronation with or without load and full supination with or without load. Mimics, 3-matic Medical, Geomagic, and Photoshop were used to reconstruct 3-dimensional models. The contact area of the radiocapitellar joint was measured. Shifting of the center of the contact area of the radiocapitellar joint was measured. RESULTS: The axial load added 8.6% and 10.5% contact area to pronation and supination without load, respectively. From pronation without load, the center of contact area significantly shifted 2.4 ± 1.1 mm anteromedially to supination without load and shifted by 1.0 ± 0.5 mm to the center of the radial head compared with the pronation with load. The center of the contact area significantly shifted 2.4 ± 1.5 mm anteromedially from the pronation to the supination under loading. The contact area of the tuberosity anterior in the radial head significantly increased by 14% (without load) and 8% (with load) from pronation to supination. CONCLUSION: Axial loading increases the contact area of the radiocapitellar joint. The center of the contact area of the radiocapitellar joint changed according to loading and shifted to the anterior tuberosity of the radial head from forearm pronation to supination.


Assuntos
Articulação do Cotovelo , Adulto , Fenômenos Biomecânicos , Cadáver , Articulação do Cotovelo/diagnóstico por imagem , Feminino , Antebraço/diagnóstico por imagem , Humanos , Masculino , Pronação , Rádio (Anatomia)/diagnóstico por imagem , Amplitude de Movimento Articular , Supinação , Tomografia Computadorizada por Raios X
7.
J Acoust Soc Am ; 148(6): 4037, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33379884

RESUMO

Large-distance sound propagation with high-frequency noise sources, multiple obstacles/geometry with varying acoustic impedance is common in real-life applications. To resolve the acoustic governing equations directly is often computationally costly, especially in three-dimensional space. Methods based on geometric acoustics can be more rapid. However, efforts are still being made to improve the efficiency, robustness, and the capability for complex configurations of such methods. In this paper, an efficient implementation of the rectilinear Gaussian beam tracing method is conducted, which combines rectilinear ray tracing with a proposed efficiency-matched dynamic ray tracing algorithm. A continuous medium stratification method is employed to improve the robustness. Also, a ray compression algorithm is proposed to save computation time. Numerical tests show that computation acceleration up to tenfold is achieved, benefiting rapid estimation of large-distance sound propagation. A standard octree data structure is employed in the code, which accelerates ray tracing in the testing cases with complex geometries. The efficiency and capability of the solver are demonstrated by studying several benchmark problems with varying complexity.

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