Consumer Product Safety ; Drinking Water ; standards ; Equipment Safety ; Food Safety ; Public Health ; instrumentation ; methods ; Safety Management ; Water Supply

Environmental Monitoring ; methods ; Environmental Pollutants ; analysis ; Microchip Analytical Procedures

The treatments of infected bone defects are still a major clinical problem.In recent years,local delivery systems applied as anti-infection and bone repair material become a hot research topic.In this review,we discuss various influence factors such as osteoinductive growth factors,antibiotics,cartier material,extended release methods.We also introduce the recent progress in the development of local delivery system for the treatment of infected bone defects.

The enzymological characterizations of site-mutagenized rat recombinant DNA polymerase?, RQ182 and RQ183 were studied The phosphocellulose column chromatographies showed that the mutant and the wild DNA polymerases were all eluted by about 0.5 mol/ L KCI, but the denatured DNA-cellulose chromatographies showed that although the wild enzyme was eluted by 0.35 mol/L KCI, RQ182 and RQ183 were eluted by 0.55 and 0.45 mol/L KCI, respectively, indicating that the binding abilities to DNA of the mutant enzymes were increased. Km values for the substrate (dTTP)of the wild enzyme, RQ182 and RQ183 were determined as 38.5, 34.5 and 111.1 ?mol/L, respectively,and the Km values for the primer (oligo(dT)) were 1.28, 1.96 and 6.58 ?g/ml, respectively. The results showed that the affinities of RQ183 to the substrate and the primer were decreased dramatically. It is suggested that Arg182 and Arg183 were involved in the active site function of DNA polymerase ?, in binding to DNA template, in recognizing of primer, and in binding to and catalyzing of substrates of the enzyme.

Objective To observe the effects of treadmill training on the expression of axonal guidance factor Netrin-4 and its receptor deleted in colorectal cancer (DCC) protein in the brains of rats with cerebral ischemia.Also to explore how training promotes the recovery of neurological function after cerebral ischemia.Methods Sixty-three adult, male Sprague-Dawley rats were randomly divided into a sham group (n =9) , a model group (n =27) and an exercise group (n =27).A modified version of Longa's method was used to establish an animal model of cerebral ischemia by occluding the right middle cerebral artery (MCAO) in the rats of the model and exercise groups while the rats of the sham group were subjected to the same surgical procedure except that no thread was inserted.The rats of the exercise group were given treadmill training beginning 24 h after the modeling, while those of the other two groups were left on the treadmill without training.The rats' neurological functioning was tested by assigning modified neurological severity scores (mNSS) on the 3rd, 7th and 14th day after modeling.Then the ischemic brain tissue was dissected to detect the expression of Netrin-4 and DCC protein using western blotting and immunofluorescent staining and analysis.Results On the 3rd, 7th and 14th day after modeling, the model and exercise groups had significant differences in their average mNSS scores when compared to the sham group.The average mNSS scores of the exercise group on the 7th and the 14th day were significantly lower than those of the model group at the same time point.The average expression level of Netrin-4 and DCC protein in the exercise group was significantly higher in than the model group on the 7th and 14 th days.Immunofluorescent staining showed that Netrin-4 was mainly observed in the blood vessels and astrocytes in the ischemic brain area.DCC protein was found mainly in neural processes and astrocytes in the same area.Conclusions Treadmill training can improve the recovery of neurological function after cerebral ischemia.Its mechanisms may be partly attributed to up-regulating the expression of Netrin-4 and DCC protein in the ischemic brain area, which strengthens the regeneration and reconstruction of nerves and blood vessels.

Objective To investigate the factors of influence in post-traumatic stress bleeding.Methods The clinical data of 1986 trauma patients and postoperative patients in recent 5 years were studied retrospectively,and cases with or without stress ulcer bleeding were comparatively analyzed.Results The incidence of stress ulcer bleeding in cases with serious injury was significantly higher than in those with mild injury(P

【Objective】To investigate the relationship of plasma renin activity(PRA),angiotensin Ⅱ(Ang Ⅱ) and aldosterone(ALD) activities with syndrome patterns in patients with ventricular remodeling following myocardial infarction,and to supply neuroendocrine evidence for syndrome differentiation of ventricular remodeling following myocardial infarction.【Methods】Sixty patients with ventricular remodeling following myocardial infarction were classified as Qi stagnation and blood stasis(pattern 1,n=16),phlegm-turbidity blockage(pattern 2,n=15),yangQi deficiency(pattern 3,n=16) and yin-blood deficiency(pattern 4,n=13).Radioimmunoassay(RIA) was used to measure plasma renin,Ang Ⅱ and ALD levels in acute myocardial infarction patients 7 days after onset,and cardiac color ultrasound was used to examine left ventricular function.【Results】In patients with ventricular remodeling following myocardial infarction,left ventricular end diastolic diameter(LVEDD),left ventricular end diastolic volume(LVEDV),left ventricular end systolic volume(LVESV),and left ventricular ejection fraction(EF) increased as compared with those in the healthy.LVEDD,LVESV and LVEDV became larger in patients with pattern 3 and pattern 1 than those in patients with pattern 2 and pattern 4(P

Objective To establish a new method to identify and analyze Qingdai Powder and its composition.Methods X-ray Diffraction with Fourier pattern was used.Results The standard X-ray diffraction with Fourier pattern and characteristic diffraction peaks of Qingdai Powder and its composition drugs were obtained.Conclusion The powder X-ray diffraction method can be used as a simple and convenient method for the identification of Qingdai Powder and its composition drugs.

The induction of DNA single-strand breaks(ssb)by exposure to hematoporphyrin photosensitizer(PSD-007)followed by photoirradiation was observed in mice leukemia cells(L7712)in vitro. DNA ssb increased with the increase of dose of light in the rangeof 6.3-21 J/cm2 after treatment with 30?g/ml PSD-007. In lower concentration(1?g/ ml)of the drug,no ssb could be estimated after light exposure. Whan the concentration of PSD-007 was increased from 10 to 30?g/ml, however, the amount of ssb showed a rapid increase and tend to reach a plateau at 50ug/ml.comparing with ?-ray irradiation, we observed that PSD-007 could not increase the amount of ssb in cells irradiated with ?-ray and the most of ssb could be rejoined after incubation at 37℃ for 1 hour in the presence of PSD-007. However, DNA ssb induced by photosensitizer and light could not be repaired in post-photorad iated incubation. It is suggested that there exist some differences between the damages induced by photosensitization and by ioning radiation.From our experiment, we believe that DNA damage of cells is an early and critical event in photosensitization, which is different from that induced by y-ray irradiation.

The proposal to promote the commercialization of new insect-resistant GM cotton,GM corn and other major products in 13th Five Year Plan on National Science and Technology Innovation ,has put forward a test to the government's ability to manage GM crops cultivation.Only a few species of GM crops,not including food crops,have been commercialized in China,we lack experience in GM crops cultivation management.Taking USA,where the farmers cultivate huge areas of GM crops,as a comparison object,the examination and approval procedures before cultivation,GM crop growers' obligation of the management,the methods to reduce mingling of GM crops and non-GM crops are compared.And concludes that the differences in legal status of GM crops,the intellectual property regime and labeling regulation,the ability of relative stakeholders to implement segregation measures and bear loss lead to different regulation on GM crops cultivation management in USA and China.The government combine the domestic current situation of the agricultural environment in our country,and focus on substantial risk in the safety management of GM crops in cultivation management is advised.The competent department of agriculture,researchers and seed traders should work together to help guide growers to avoid the economic disputes due to mingling and reduce the impact on the ecological environment.