Modeling and simulation of excitation- contraction coupling of fast-twitch skeletal muscle fibers.

Background: The current excitation-contraction coupling model of fast-twitch skeletal muscle fibers cannot completely simulate the excitation-contraction process.

Objective: To solve this problem, this study proposes an excitation-contraction model of fast-twitch skeletal muscle fibers based on the physiological structure and contractile properties of half-sarcomeres.

Methods: The model includes the action potential model of fast-twitch fiber membranes and transverse tubule membranes, the cycle model of 𝐶𝑎2+ in myofibril, the cross-bridge cycle model, and the fatigue model of metabolism.

[Histomorphology observation of canine whole facial nerve treated with chemically extracted acellular methods].

Objective: Using chemically extracted acellular methods to treat extracranial section of the canine whole facial nerve, to evaluated its effects on nerve structure and the removal extent of Schwann cells and myelin.

Methods: Twenty whole facial nerves were exposed from 10 canines [weighing (18 +/- 3) kg]. The extracranial trunk of canine facial nerve and its branches (temporal branch, zygomatic branch, buccal branch, marginal mandibular branch, and cervical branch) were dissected under light microscope.

[Treatment of degenerative lumbar spondylolisthesis through posterolateral fusion and fixation with pedicle screws].

Objective: To explore internal fixation whether can improve the clinical outcomes of decompression and posterolateral fusion in patients with degenerative lumbar spondylolisthesis.

Methods: From December 1998 to December 2005, 49 patients who had degenerative lumbar spondylolisthesis underwent decompression and posterolateral fusion without (group A, 21 cases) or with (group B, 28 cases) internal fixation (CD HORIZON M8 system). There were 12 males and 37 females with a mean age of 58.