Evaluating effectiveness and safety of combined percutaneous transhepatic gallbladder drainage and laparoscopic cholecystectomy in acute cholecystitis patients: Meta-analysis.

Background: Acute cholecystitis (AC) is a common disease in general surgery. Laparoscopic cholecystectomy (LC) is widely recognized as the "gold standard" surgical procedure for treating AC. For low-risk patients without complications, LC is the recommended treatment plan, but there is still controversy regarding the treatment strategy for moderate AC patients, which relies more on the surgeon's experience and the medical platform of the visiting unit.

Empirical study on clique-degree distribution of networks.

The community structure and motif-modular-network hierarchy are of great importance for understanding the relationship between structures and functions. We investigate the distribution of clique degrees, which are an extension of degree and can be used to measure the density of cliques in networks. Empirical studies indicate the extensive existence of power-law clique-degree distributions in various real networks, and the power-law exponent decreases with an increase of clique size.

Geographical networks evolving with an optimal policy.

In this article we propose a growing network model based on an optimal policy involving both topological and geographical measures. In this model, at each time step, a node, having randomly assigned coordinates in a 1x1 square, is added and connected to a previously existing node i, which minimizes the quantity ri2/kialpha, where ri is the geographical distance, ki the degree, and alpha a free parameter. The degree distribution obeys a power-law form when alpha=1, and an exponential form when alpha=0.