Small molecule covalent inhibitors, or called as irreversible inhibitors, are a type of inhibitors that exert their biological functions by irreversibly binding to target through covalent bonds. Compared with non-covalent inhibitors, covalent inhibitors have obvious advantages in bioactivity. Nevertheless, these agents may also exhibit larger toxicity once off-target effects arise. This "double-edged swords" property often leads drug researchers to avoid attaching them. In recent years, some problems such as drug resistance are difficult to be solved with reversible inhibitors leading researchers to pay more attention on the covalent inhibitors. In this review, we shall make a short summary to the recent research progress of covalent inhibitors and the interaction modes between covalent inhibitors and their target protein residues.

Objective To evaluate the sanitation of the ecological toilet systems used in rural areas. Methods The urine diverting Ecosan toilets in rural areas of Guangxi province were observed for the utilization, maintenance and sanitization. The hygienic evaluation was carried out according to the Hygienic Standards for Excreta Sanitization GB 7959-87. Results The new type of urine diverting Ecosan toilets could meet the requirements of non-hazard treatment of excreta. Conclusion Such toilet system should be developed in most parts of Guangxi.

Objective To investigate the effect of aprotinin on the inflammation response to reinfusion of shed blood during operation after being aspirated, filtered and washed using cell saver.Methods Twenty-four ASA I - II patients undergoing elective spinal surgery under general anesthesia were randomly divided into 2 groups: aprotinin group ( n = 12) and control group ( n = 12) .The patients were premedicated with intramuscular pentobarbital 0.1 g and atropine 0.5 mg. Anesthesia was induced with propofol 2 mg ? kg -1 , fentanyl 2-4 ?g ? kg-1 and vecuronium 0.1-0.3 mg ? kg-1 and maintained with isoflurane, propofol infusion and intermittent i. v. boluses of fentanyl and vecuronium. The patients were mechanically ventilated after tracheal intubation. In aprotinin group aprotinin 10 ? 105 IU was given before skin incision and another dose of aprotinin 10 ? 105 IU was continuously infused during operation. The blood shed during operation was collected, anticoagulated with heparin, filtered, washed and reinfused using AutoLog cell saver. Blood samples were taken from CVP line before skin incision (T1 , baseline), 30 min after reinfusion of salvaged bloods (T2) and at the end of operation (T3 ) for WBC and neutrophil granulocyte counts and determination of expression of CD11b and CD18 on the surface of neutrophil granulocytes using flow cytometry. Results The two groups were similar with respect to the general condition of the patients, duration of operation and account of shed blood reinfused. (676? 353) ml was reinfused in control group. The expression of CD11b and CD18 on the surface of neutrophil granulocytes increased significantly at T2 and T3 as compared to the baseline at T1 in control group ( P

Objective To evaluate the variation of the blood flow in anterolateral femoral head by ligating different amount of extracapsular arteries. Methods Thirty six hips of 18 mongrel puppies were divided into A、 B、 C、 D and E groups. In group A, only one peripheral artery was ligated randomly. In groups B, C, D,and E, 2, 3, 4, and 5 peripheral arteries were respectively ligated. The blood flow in anterolateral femoral head in 18 mongrel puppies was measured before and after the ligation of the arteries by using of Hydrogen clearance technique. Results 1) The average blood flow in anterolateral femoral head was (0.1397?0.0515) ml?min-1?ml-1. 2) The mean blood flow in the anterolateral femoral head was slightly decreased after one to two of the extracapsular main arteries were ligated but there was no statistical difference. However, the mean blood flow was decreased significantly after more than three arteries were ligated. Conclusion 1) Hydrogen clearance technique is a quite simple, economic and reliable method for estimation of blood flow perfusion in various tissue. 2) The efficiency of blood supply of the anterolateral femoral head in puppies depends at least upon three of the major extracapsular arteries.

Deep venous thrombosis is a common and serious complication after orthopedics operation, with the characteristics of high incidence rate and death rate, its formation mechanism and the treatment is becoming more and more attention of scholars. Establishment of animal model of deep venous thrombosis can further explore the pathological process of thrombosis or dissolution, is an important means to research of thrombosis mechanism and evaluation of therapeutic method. This review discussed the basic principle of deep venous thrombosis, the selection of experimental animals and making method of animal models.
Animals ; Disease Models, Animal ; Venous Thrombosis ; etiology

Objective To study mental state of children with asthma and psychosomatic symptoms of their parents. Methods Eysenck Personality Questionnaire(EPQ) for children and Rutter's Behavior Ques-tionnaire were applied to 36children aged 6～14with asthma, SCL-90 was applied to their parents. Children from the same kindergartens and schools and their parents were sampled as control matched by age, sex etc.Results Children with asthma had more personality problems than normal children. The E.N scores of EPQ scales were higher in asthma children than in normal samples. The rate ot behavior problems was 33.3 %; Par-ents of children with asthma had higher scores of S SCL-90 than parents of children as control, espeeially in de-pression, anxiety, somatic complaints and terror. Conclusion Children with asthma and their parents, It is im-portant to take some active measures to intervene psychological and behavioral problems of children with asth-ma and psychosomatic symptoms of their parents.

With the development in the diagnosis and treatment of urological diseases and im-provement of minimally invasive technology in recent years, some apparent diseases and concepts of new technology can't be mentioned in teaching practice including functional diseases of lower urinary tract, further discussion of prostatic cancer and minimally invasive technology, etc. We elaborated on the importances, teaching significances and key points of these teaching contents in order to improve the knowledge teaching system.

Many beneficial bioactive substances were produced by Paenibacillus polymyxa such as antibiotics, antimicrobial proteins, plant hormones and flocculants. These bioactive substances also could be produced by Paenibacillus polymyxa making it show excellent prospect in biological control of plant diseases, treatment of mankind and animals. This article summarizes research advances in Paenibacillus polymyxa and their bioactive substances.

Objective To construct an oral recombinant DNA vaccine of Helicobacter pylori(H. pylori) neutrophil activating protein (Hp-NAP), and to evaluate its immunotherapeutic effects. Methods The napA gene (encoding Hp-NAP) was amplified by poly mera se chain reaction(PCR) and cloned into TA cloning vector pBT. After nucleotide s equencing and sequence analysis, the target sequence was subcloned into an eukar yot ic expression vector pIRES. Then the identified recombinant plasmid, pIRES-napA , was transformed into a live attenuated Salmonella typhimurium(S. typhimurium ) strain SL7207, and lavaged into a long-term(30 weeks) model of BALB/c mice infected by Sydney strain(SS1) of H. pylori. Results A 435 bp target gene of napA was amplified by PCR. Seq uenci ng and BLAST analysis showed that most of the cloned napA sequence was homologou s with that of SS1 strain of H. pylori. provided by GenBank, and the homolog y of neucleotide and protein was over 98%, respectively. PCR and restriction enzyme digestion id entification indicated that a recombinant live attenuated S. typhimurium DNA vaccine strain carrying Hp-napA gene was successfully constructed. After 4 wee ks of oral immunization, 75% of mice treated with DNA vaccine were rapid urease test negative, while those with vacant plasmid or normal saline alone were all p ositive (P= 0.0476). The titer of serum Hp-NAP antibody was signific antly elevated in treatment group. Conclusions The successful construction of an effective oral recom binant DNA vaccine of Hp-NAP may be helpful for the further development of polyvalent DNA vaccine against H. pylori infection.