Shortest-Path Fractal Dimension for Percolation in Two and Three Dimensions

We carry out a high-precision Monte Carlo study of the shortest-path fractal dimension \dm for percolation in two and three dimensions, using the Leath-Alexandrowicz method which grows a cluster from an active seed site. A variety of quantities are sampled as a function of the chemical distance, including the number of activated sites, a measure of the radius, and the survival probability. By finite-size scaling, we determine \dm = 1.130 77(2) and $1.375 6(6)$ in two and three dimensions, respectively. The result in 2D rules out the recently conjectured value \dm=217/192 [Phys. Rev. E 81, 020102(R) (2010)].Comment: 5 pages, 4 figure

The Effect-enhancing and Toxicity-reducing Action of the Extract of Herba Scutellariae Barbatae for Chemotherapy in Hepatoma H22 Tumor-bearing Mice

ObjectiveTo investigate the effect-enchancing and toxicity-reducing action of the extract of Ban Zhi Lian (Herba Scutellariae Barbatae, EHSB) for chemotherapy in hepatoma H22 tumor-bearing mice.MethodsThe tumor-bearing mice were divided into 6 groups randomly: a model group, a high dose EHSB group, a low dose EHSB group, a 5-fluorouracil (5-FU) group, a 5-FU+high dose EHSB group and a 5-FU+low dose EHSB group, and with a normal group set as the controls. All the groups were treated for 10 days. The life prolongation rate, toxic reactions of chemotherapy, WBC count, the body weight, tumor weight, thymus index and spleen index, and phagocytic function of intra-abdominal macrophages were investigated in the H22 tumor-bearing mice.ResultsThe increase of the body weight in both the 5-FU+EHSB groups was significantly higher than that in the 5-FU group, with the toxic reactions such as anorexia, abdominal distension and emaciation significantly alleviated. Growth of the tumor was significantly inhibited in the high dose EHSB group, the 5-FU group, the 5-FU+high dose EHSB group, and the 5-FU+low dose EHSB group. The survival time in the 5-FU+high dose EHSB group and the 5-FU+low dose EHSB group was significantly prolonged as compared with that of the 5-FU group. The life prolongation rate was 98.72% in the 5-FU+high dose EHSB group and 52.11% in the 5-FU+low dose EHSB group. Growth of the transplanted tumor was significantly inhibited in the high dose EHSB group, the 5-FU group, the 5-FU+high dose EHSB group, the 5-FU+low dose EHSB group. The tumor inhibition rate in the high dose EHSB group, the 5-FU group, the 5-FU+high dose EHSB group and the 5-FU+low dose EHSB group was 36.98%, 42.26%, 65.28% and 52.45%, respectively. 5-FU combined with a high-dose EHSB could significantly enhance the tumor inhibition rate (P<0.05). The thymus index and the spleen index significantly increased in the high dose EHSB group, and atrophy of the immunological organs induced by chemotherapy was improved in the 5-FU+high dose EHSB group and in the 5-FU+low dose EHSB group. The WBC count decreased significantly in the 5-FU group, but increased in both the 5-FU+EHSB groups. The phagocytic function of intra-abdominal macrophages was increased in both the 5-FU+EHSB groups, with the phagocytic rate and the phagocytic index increased by 78.55% and 81.63% in the 5-FU+high dose EHSB group and by 43.97% and 44.90% in the 5-FU+low dose EHSB group.ConclusionsEHSB can significantly enhance the tumor inhibition rate of 5-FU, reduce the toxic effects, prolong the survival time, and improve immune function in the H22 tumor-bearing mice

Clinical Effects of Shenqi Fuzheng Injection in the Neoadjuvant Chemotherapy for Local Advanced Breast Cancer and the Effects on T-lymphocyte Subsets

ObjectiveTo evaluate clinical effects of Shenqi Fuzheng Injection in the neoadjuvant chemotherapy for local advanced breast cancer and the effects on T-lymphocyte subsets.MethodsDuring the period from 2000 to 2005, 126 patients with local advanced breast cancer were treated with the neoadjuvant chemotherapy. They were randomly divided into the following two groups: a control group of 61 cases treated by chemotherapy alone and a study group of 65 cases treated by chemotherapy plus Shenqi Fuzheng Injection. All the cases of both groups were given the CEF (CTX 500 mg/m2, d1, 8; EPI 40 mg/m2, d1, 8; and 5-Fu 500 mg/m2, d1,8) regimen. The clinical effects, the effects on T-lymphocyte subgroup and NK cells, and the toxic side effects were observed.ResultsAll the patients completed two cycles of the chemotherapy, and the efficacy and the toxic side effects were evaluated. For the primary tumor in the breast, the total effective rate was 69.2% (45/65) in the study group and 49.2% (30/61) in the control group with a statistically significant difference in the intergroup comparison (χ 2=5.251, P=0.022, < 0.05). There was no progression of the disease in both the groups, and there were no grade IV toxic side effects in the two groups. The major toxic responses were myelosuppression and gastrointestinal reaction, which were milder in the study group than the control group, and with a shorter recovery course in the former than the latter. Besides, an obvious rise of the T-lymphocyte subgroup and NK cells was found in the study group after the neoadjuvant chemotherapy, with a very significant difference from the controls (P < 0.01).ConclusionShenqi Fuzheng Injection can improve and regulate immune function of the patients with local advanced breast cancer given the neoadjuvant chemotherapy, and therefore it can enhance the curative effect and reduce the side effect as well

Crossover from Isotropic to Directed Percolation

We generalize the directed percolation (DP) model by relaxing the strict directionality of DP such that propagation can occur in either direction but with anisotropic probabilities. We denote the probabilities as $p_{\downarrow}= p \cdot p_d$ and $p_{\uparrow}=p \cdot (1-p_d)$, with $p$ representing the average occupation probability and $p_d$ controlling the anisotropy. The Leath-Alexandrowicz method is used to grow a cluster from an active seed site. We call this model with two main growth directions {\em biased directed percolation} (BDP). Standard isotropic percolation (IP) and DP are the two limiting cases of the BDP model, corresponding to $p_d=1/2$ and $p_d=0,1$ respectively. In this work, besides IP and DP, we also consider the $1/2<p_d<1$ region. Extensive Monte Carlo simulations are carried out on the square and the simple-cubic lattices, and the numerical data are analyzed by finite-size scaling. We locate the percolation thresholds of the BDP model for $p_d=0.6$ and 0.8, and determine various critical exponents. These exponents are found to be consistent with those for standard DP. We also determine the renormalization exponent associated with the asymmetric perturbation due to $p_d -1/2 \neq 0$ near IP, and confirm that such an asymmetric scaling field is relevant at IP.Comment: 8 pages, 8 figure