Given the complexity of diseases and etiology of multiple targets and links,therapies with multi-drug combination towards multiple targets are better options for treating serious diseases,such as cancer,than a single-target medicine. Multi-drug combination may cause interactions at different levels,but the efficacy of these drugs manifests itself as synergism,addition or antagonism. Because there is no reliable quantitative method for synergism,addition and antagonism that can simultaneously withstand double test of mathematics and pharmacology,the development of novel drug combinations has come to a standstill. By exchanging the equivalent doses and introducing two basic principles that have been long neglected in the pharmacological field(the sequential principle for multi-drug use and the collective property of efficacy)into the geometrical analysis of the dose- effect relationships,the author has found the mathematical laws for the expected additive effect in multi-target drug combina?tion,and worked out a universal formula. The dose-effect relationship of the expected addition is a number set function of multi-drug combination doses with a closed interval,which performs as a belt in a two- dimensional coordinate,while the actual observed one presents as a curve. The number of curves that constitute the belt increases exponentially whith the incnease of combined drugs. By solv? ing the equation groups composed of the belt and the curve,related parameters in multi-drug combina?tion can be precisely calculated,such as dose ranges of synergism,addition and antagonism,as well as combination indexes based on dose and one based on efficacy,which will also provide a quantita?tive analysis method for interactions between various factors in biological systems.

tuftsin,a physiologically active peptide,can promote phagocytosis,basically stimulates the macrophages or neutro-phils and improve their phagocytotic function.tuftsin can not di-rectly kill tumor cells.Due to its short structure and the charac-teristics of being susceptible to hydrolysis,it is difficult for tuft-sin to be made into medicine and applied clinically.However, derivatives of tuftsin-series and combination of tuftsin with other drugs can greatly enhance the cytotoxic effect on tumor cells of tuftsin.It has a broad prospect of research,especially deriva-tive-TP has a significant anti-tumor effect.Its mechanism is clear and its is expected to become a new type of anti-tumor bio-logical response regulator.

Apoptosis is a cell suicide process with a major role in development and homeostasis in bodies. Dysregulation of apoptosis, involved with inhibitors of apoptosis (IAPs), contributes a variety of disease states including cancer. The recent progress of members of IAPs family and the anticancer strategy against IAPs is reviewed in this paper.

Apoptosis is involved in a variety of physiological and path ol ogical conditions. Bax is proapoptotic member in signal pathway of apoptosis. It will contribute to the survival of cells if reducing its expression and activit y. Advances in factors influencing Bax, biological effects induce d by Bax knock-out, and antisense nucleotides targeted to Bax-mRNA were r eviewed in this article during recent years.

Epidermal growth factor receptor (EGFR) tyrosine kinase is over-expressed in numerous human tumors, which plays pivotal roles in cellular signal transduction, and it is involved in a variety of tumor cellular behaviors such as proliferation, metastasis, angiogenesis and so on. Many investigations have indicated that tumor growth can be suppressed by inhibiting EGFR tyrosine kinase activity. Currently, several EGFR tyrosine kinase inhibitors are in clinical trial stage.

Concern on antibiotics contamination has been raised because of its serious environmental impact in recent years.The application of antibiotics,measurement method for antibiotics,mechanism of antibiotics degradation,and impact of antibiotics contamination on environment and human health were reviewed and commented.The advisable solution and future researches were prospected in this review,too.

Objective To study significance of anicteric biliary tract dilatation in early diagnosis and treatment of patients with periampullary carcinoma.Method Review the resection rate and survival rate of 16 periampullary carcinoma patients with anicteric biliary tract obstruction found out by B-ultrasound,CT or PTC during 13 years(1986-1999).Result The operative resection rate was 87.50%(14/16) ,5-year survival rate was 43.75%(7/16),3-year survival rate was 62.50%(10/16).Conclusions Biliary tract dilatation existed before icterus occurred,while syndromes such as upset of upper abdomen,reclusion, epigastralgia distention and anorexia, may occur 1-3 months ahead of icterus occurred in patients with periampullary carcinoma. If the patient has syndromes mentioned above, more than 40 years of age and biliary tract dilatation found by B-ultrasound, CT,PTC or ERCP, periampullary carcinoma should be considered. The patients should be checked by operation,so as to raise the operative resection rate and survival rate.

Apoptosis is involved in a variety of diseases. Cysteine aspartate specific protease (caspase), a protease family which executes apoptosis, plays a crucial role in course of apoptosis. It can be activated through various pathways. Some natural and synthetic caspase inhibitors will strengthen anti apoptotic action through inhibiting one or several caspase activity, and will become effective means in treating diseases caused by overapoptosis.

Livin is a novel member of IAPs (inhibitors of apoptosis protein) family, which is expressed highly in a variety of tumors but not in majority of normal tissues. This protein contains a BIR domain and a RING finger domain just like other members of IAPs. It will be of great sigificance to investigate the relationship between Livin and tumors, and it might be a potential target for anti-cancer drugs.

AIM: Antisense oligonucleotides against livin were designed with computer software. METHODS: Antisense oligonucleotides were designed according to the secondary structure of livin mRNA which was simulated with RNAdraw and Sfold. And then these oligonucleotides were transfected into Hela cells for inducing apoptosis. RESULTS: Five antisense oligonucleotides were designed using RNAdraw and Sfold, and effectively induced Hela cell apoptosis. CONCLUSION: The approach is effective and feasible to design antisense oligonucleotides by means of calculation with two kinds of software.