Backup power should be equipped in hospitals in order to prevent the medical risks.At present,there are three choices of the backup power including UPS,EPS and diesel generator.The principles of three backup powers are introduced.Methods for equipping backup power are also discussed to guarantee the security of power supply system for emergency medical equipment.

OBJECTIVE: To evaluate function and application of various biomaterials in tissue engineering repair skull defect, and to seek a reasonable skull substitutes. METHODS: Using "tissue engineering, skull defect, stem cells, cytokines, composite" as key words in Chinese, and using "tissue engineering, skull defect, mesenchymal stem cells, cytokines, materials" as key words in English, a computer-based online search was performed for publications from January 1993 to October 2009. Articles concerning biomaterials and tissue engineering skull defect repair were included. Articles describing repetitive study or Mete analysis were excluded. Function of various biomaterials in tissue engineering repair skull defect was assess in 17 articles. RESULTS: Stem cell technique is to obtain seed cells from a few myeloid tissues. Following in vitro induction and amplification, cells at a certain number could compound with stents, and construct tissue-engineered bone in vitro. The cells could sustain the biological features of osteoblasts, and fuse with bone tissue in the recipient site. Simultaneously, it could avoid the occurrence of immunological rejection. Two or over materials were compounded together, or biomaterial surface received various modification. These could promote adhesion between cells and materials, elevate cell bioactivity and maintain biological function. Following moved into seed cells using some vectors, the latter ossified in bone defect site, and secreted suitable bone growth factor, induced the differentiation of peripheral non-oriented osteogenitor cells into oriented osteogenitor cells, which could harvest adequate seed cells with osteogenic activity in a short time, and accelerate the healing of skull defects. The composite made by using three-dimensional virtual imaging and computer numerical control modeling techniques has the advantages of medical composite, precise anatomical consistency with surrounding tissues of skull defects, and perfect appearance. CONCLUSION: At present, no material can be accorded with the requirement of bone tissue engineering. Combination of some materials or modification of biomaterial surface can promote adhesion of cells and materials, elevate cell biological activity, and maintain biological function, which are presently hot focus of tissue engineering research of biomaterials.

Probability of causation (PC) was used to facilitate the adjudication of compensation claims for cancers diagnosed following exposure to ionizing radiation. In this article, the excess cancer risk assessment models used for PC calculation are reviewed. Cancer risk transfer models between different populations, dependence of cancer risk on dose and dose rate, modification by epidemiological risk factors and application of PC are also discussed in brief.

AIM: To assess the changes of macular thickness of acquire immunodeficiency syndrome ( AIDS) patients.
METHODS:The study based on the data analysis of 38 human immunodeficiency virus ( HIV ) positive patients ( 64 eyes ) . According to CD4 count and whether cytomegalovirus retinitis ( CMVR) happened, the patients were divided into 3 groups. Group A included 16 patients (32 eyes), in which CD4 count was < 50cells/μL and CMVR did not happen. Group B included 10 patients ( 20 eyes), in which CD4 count was>50cells/μL and CMVR did not happen. Group C included 12 patients (12 eyes), in which CD4 count was < 50cells/μL and CMVR just happened. Group D included 10 healthy people ( 20 eyes ) , as normal control group. By using optical coherence tomography ( OCT ) , thickness of retina along with a 1mm diameter circle centered on macular was evaluated.
RESULTS:The mean foveal thicknesses in groups A, B, C and D were 254. 03±15. 63μm, 263. 11±17. 12μm, 304. 50±50. 62μm and 257. 64±8. 54μm in order. Compared with foveal thickness in each group, there were significant differences in general (F=12. 933, P=0. 000). The mean foveal thickness in groups CMVR increased, which was of significant difference (P= 0. 000), compared with other groups.
CONCLUSION: CMVR can impair the structure and function of macular, which then seriously affects the visual function of patients. It's helpful to understand the progress and prognosis of CMVR disease by observing macular structure with OCT in early time.

Objective:To investigate a potential role of Toll-like receptor 4(TLR4) ,a pathogen pattern recognition receptor, in the early phase of severely burned rats. Methods: Rats burn model(30% of total body surface area[TBSA],Ⅲgrade) were established with vapor at 108 C for 8 seconds. Rats were sacrificed before and 2,5,12,24,48 and 72 h after burning, and the spleen specimens and peripheral blood samples were harvested. TLR4 mRNA and TNF-?mRNA expression in splenocyte was measured by reverse-transcription PCR(RT-PCR); the expression of TLR4 protein were measured by Western bloting; the endothelial toxicity concentration in plasma was detected by limulus lysate test. Results: It was found that the expression of TLR4 mRNA.TNF-?mRNA,TLR4 protein,and the level of ET were significantly increased in burned group compared with normal control group. The expression of TLR4 mRNA and protein peaked at 8 h after burning, the expession of TNF-?mRNA peaked at 12 h.and the level of ET peaked at 8 h after burnings the peak values of them were (3. 66?0. 51),(2. 27?0. 19), (1.65?0. 23),and (11. 68?2. 63) Eu/ml, respectively, all significantly higher than those of the control group(P

Objective To evaluate the 64-slice CT angiography in characterizing the coronary venous anatomy and the arterio-venous relationship.Methods Sixty-four slice CT coronary veins angiography images of 300 patients(187 men and 113 women,)were analyzed.The visibility of the coronary veins and arterio-venous spatial relationship were assessed qualitatively on two-and three-dimensional displays.The diameter of the coronary sinus ostium(CSO),middle cardiac vein ostium(MCVO)and posterior vein of left ventricle ostium(PVLVO)were measured.All data was statistically processed with SPSS for Windows.Results The CS,great cardiac vein(GCV)and MCV could be clearly visualized in all of the images.1-3 branches of PVLV could be observed in 273 patients(91.0%).Small cardiac vein(SCV)and Marshall vein were found in 56(18.7%)and 24(8.0%)cases respectively.Three patients had permanent vena cava superior on the left and one patient had a CS diverticulum.Posterior descending artery(PDA)was concomitant with MCV in 189 cases(63.0%)and intersected with MCV in 96 cases(32.0%).Left circumflex artery(LCX)was concomitant with CS in 122 cases(40.7%),intersected with MCV in 15 cases(5.0%),and intersected with PVLV in 104 cases(34.7%).There were no significant differences in age,sex and CHD groups among CSO,MCV,PVLV value.The supero-inferior diameter of CSO had a significant difference between male and female(F=6.67,P＜0.05).Conclusion Sixty-four slice CT venous angiography is able to be used for guiding electrophysiological procedures,which is especially useful due to the considerable variations in venous anatomy.

Objective To establish and evaluate a gene microarray for determination katG mutations of Mycobacterium tuberculosis isolates associated with resistance to isoniazid(INH).Methods A panel of probes were designed and gene chips were prepared by dotting.Mycobacterium tuberculosis isolates resistance to 5 drugs was determined by proportional dilution methods.Amplicons of Mycobacterium tuberculosis isolates were detected by our chip and sequenced.Results The drug resistance rate of the isolates to at least one of the anti-tuberculosis drugs was 70.8%(97/137).45 strains out 137 Mycobacterium tuberculosis isolates was resistant to INH(32.8%).katG was successfully amplified from 100% of the susceptible strains and 88.9%(40/45)resistant strains.4 of 45 INH resistant isolates' katG were deleted.27 of 40(67.5%) katG has been detected to have katG 315 codon mutations.The mutations were 315 AAC(Asn,13/40), ACC(Thr,6/40),ACA(Thr,4/40),ATC(Ile,2/40),AGC(Arg,2/40).The mutation rate of katG analyzed by gene chips we prepared were identical to katG sequencing.Conclusion The gene microarray techniques we developed for determination of Mycobacterium tuberculosis resistance to INH are specific, sensitive and may be used as an alternative in clinical laboratory.

OBJECTIVETo study the distribution and antibiotic resistance of the isolated pathogens from children with infectious diarrhea in Guangzhou.

METHODSThe fecal samples of 2 409 children with infectious diarrhea between January 2006 and December 2007 were collected and cultured. Pathogenic bacterium were isolated and identified by biochemical and serological methods. The antibiotic susceptibilities were tested by the Kirby-Bauer method.

RESULTSA total of 448 isolates of pathogenic bacterium (18.6%) were obtained, including Shigella (n=159), enteropathogenic Escherichia coli (n=141), Salmonella (n=76), Vibrion (n=11), fungus (n=41), and C jejuni (n=20). All of isolates of the three major pathogenic bacterium, Shigella, enteropathogenic Escherichia coli and Salmonella, were susceptible to imipenem and less than 10% of the isolates were resistant to the third generation cephalosporins and beta-lactamase inhibitors. However, the isolates showed a high resistance to ampicillin and sulfamethoxazole/trimethoprim (>75%).

CONCLUSIONSShigella, enteropathogenic Escherichia coli and Salmonella were major pathogenic bacterium of diarrhea in children from Guangzhou. The major isolates were susceptible to imipenem, the third generation cephalosporins and beta -lactamase inhibitors, but were resistant to ampicillin and sulfamethoxazole/trimethoprim.

Adolescent ; Bacteria ; drug effects ; isolation & purification ; Child ; Child, Preschool ; Diarrhea ; drug therapy ; microbiology ; Drug Resistance, Microbial ; Female ; Fungi ; drug effects ; isolation & purification ; Humans ; Infant ; Male

Objective To observe the influence of heat shock preconditioning on the expressions of heat shock protein(HSP)60,70 and induced nitric oxidase synthase(iNOS)in gastric mucosa of severely burned rats and investigate the protective mechanism of burn-induced acute gastric mucosal lesion.Methods Ninety-six Wistar rats were divided into two groups:burn(B)and heat shock preconditioning before burn(HB).The extent of gastric mucosal lesions(UI)was evaluated grossly and histologically.HSP70 mRNA expression was determined by RT-PCR.Immunohistochemical method was used to analyze the protein expressions of iNOS,HSP60 and HSP70.Results Rats in B group were induced conspicuous gastric mucosal lesions,while UI in HB group was significantly lower.The expressions of HSP70 and HSP60 were significantly increased and the expression of iNOS was obviously decreased in HB group as compared with B group.Conclusion Heat shock preconditioning protects against acute gastric mucosal lesion caused by burn through enhancing the expressions of induced HSPs and reducing the iNOS expression.