Methicillin-resistant staphylococcus aureus (MRSA) has become the main pathogen for hospital and community acquired infections. Based on the resistance mechanism of MRSA, this article reviews the reducing and eliminating effect of Chinese herb extracts on bacterial drug resistance, by means of PBP2a protein binding, γ-lactamase, plasmid, efflux system, cell structure and biofilmdamage.

Objective By comparing the tone recognition rates for different cochlear implant (CI) analog sounds ,the effects of the temporal coding strategy on tone recognition were investigated .Methods The professional announcer read 6 vowel (/a/,/o/,/e/,/i/,/u/,/ü/) of 4 different tones at a normal speed .After adjusting the am-plitude envelope and increasing the fine structure ,the audios with different sampling accuracy below 500 Hz(125 ,250? ?1500 pps) were obtained ,including 288 audio amplitude envelope adjusted and 288 not adjusted .Thirty young participants of normal hearing had tone recognition tests .The results and the tone recognition rates under two dif-ferent temporal properties were compared .Results When the temporal fine structures were combined in considera-tion ,the amplitude envelope as adjusted to match the fundamental frequency (F0) had a significant effect on the tone recognition .The tone recognition rate after amplitude envelope adjusted (80 .22％ ± 16 .32％ ) was higher than before (74 .83％ ± 20 .24％ ) [F(1 ,9)=16 .91 ,P=0 .002] .When the amplitude envelopes were combined in consider-ation ,changing the fine structure of the frequency below 500 Hz had a significant effect on the tone recognition [F (11 ,99)=38 .86 ,P<0 .001] .When the sampling precision was <375 pps ,the tone recognition had improved re-markably with the improvement of sampling precision (P<0 .004) .When the sampling precision was ≥375 pps , the effect on the tone recognition was not significant (P>0 .004) .The interaction between changing amplitude en-velopes and increasing the fine structure had a significant effect on the tone recognition [ F(11 ,99 )= 3 .78 , P<0 .001] .When the fine structure ≤375 pps ,adjustment on the amplitude envelope to increase the information of F0 had a significant impact on the tone recognition (P<0 .05) .When the fine structure was >375 pps ,the difference of the tone recognition before and after the adjustment tended to 0 (P>0 .05) .Conclusion In the CI coding strate-gy ,adjusting the amplitude envelope to get more F0 information improves tone recognition .To a certain degree ,the tone recognition improves when the sampling precision of frequency below 500 Hz is improved .Adjusting the ampli-tude envelope to F0 and increasing the temporal fine structure below 500 Hz can be combined in the same speech coding strategy to optimize the tone recognition .

Objective To study the use of the international speech test signal(ISTS) on acceptable noise level (ANL)test in Mandarin adults.Methods The Mandarin test materials and ISTS were used as test materials.The ANL test was performed on 40 normal hearing adults.For each case,the most comfortable loudness(MCL)and background noise level(BNL)were obtained.MCL minus BNL equal to ANL.Results The values of ANL under the Mandarin test materials and ISTS test materials were 39.31±6.97 and 41.85±7.60 dB HL,respectively.The values of BNL were 37.59±8.45 and 39.27±8.66 dB HL,respectively.The values of ANL were 1.53±5.61 and 2.45±5.58 dB,respectively in 40 normal hearing adults.There was no significant difference in the MCL,BNL and ANL between the test materials of Mandarin and ISTS (P＞ 0.05).Conclusion International speech test signal (ISTS) can be used on ANL test in Mandarin adults with normal hearing.

Objective To explore the feasibility of the application of music test materials in acceptable noise level (ANL) test.Methods We chose Mandarin proficiency test material,Mandarin music and accompaniment music to produce ANL test materials.The background noise was babble noise.A total of 40 normal hearing young people conduct ANL tests.Results The most comfortable loudness (MCL) obtained under the Mandarin short text test material,Mandarin music test material and accompaniment music test material were 39.10±7.43,43.85±9.53 and 44.10±10.83 dB,respectively.The maximum background noise level (BNL) were 37.91±8.65,44.52±11.23,43.65±12.89 dB HL,ANL values were 0.98±4.90,-0.90±3.78,0.45±4.65 dB S/N,respectively.The MCL and BNL values of Mandarin music test materials and accompaniment music test materials were higher than those of Mandarin short text test materials (P＜0.05),but there was no significant difference between MCL and BNL values in Mandarin music test materials and accompaniment music test materials (P ＞ 0.05).There was no significant difference in ANL among the three test materials (P＞0.05).Conclusion The music test material can be applied to the acceptable noise level test.The MCL value and the BNL value were higher under the music test material,which indicating that the acceptance of the music is higher in normal hearing people,whether or not the music test material containing lyrics has no effect on the ANL test results.

Medical Laboratory Technology now belongs to the first-level discipline of medical technology and focuses on the cultivation of technical talents.At present,there are some problems in this professional education,such as emphasizing theoretical knowledge teaching,neglecting practical skills training,weak practicability of some courses and graduates' lack of professional quality.In this study,we have combined "Teaching,Clinical and Scientific research" together.By improving the teaching staff,increasing the proportion of experimental courses,clinical skills and scientific research training,relying on "verification-synthesis-design" experiments,laboratory opening and undergraduate scientific research competitions,we have carried out professional personnel training,and have achieved better educational results,which is also helpful to the development of laboratory discipline.

Objective: To study the changes of the sensitivity of the methicillin-resistant Staphylococcus aureus (MRSA) to oxacillin after Chinese herbs. effects, so as to find Chinese medicine that can enhance the sensitivity of MRSA to antibiotics and provide new ideas for the clinical treatment of MRSA infection. Methods: A total of 33 commonly used antibacterial herbs were selected to prepare extracts, which act on clinically isolated MRSA. The broth micro dilution method was used to determine the minimal inhibitory concentration (MIC) of oxacillin on MRSA before and after the action of Chinese medicine. If there is a statistically significant difference (P ＜ 0.05), the medicine is effective. Results:The MIC of oxacillin on MRSA were 128-512 μg·ml-1, after the effect of Bletilla extracts, the change of MIC showed a statistically significant difference (P ＜ 0.05), which could increase the sensitivity of MRSA (271) to oxacillin. Conclusion:Bletilla extracts can enhance the sensitivity of MRSA (271) to oxacillin and the compatibility with antibiotics is expected to restore the efficacy of antibiotic.

Clinical laboratory instrumentation is a practical course. In order to change the limitations of the experimental site and the lack of large automatic testing instruments in the current teaching, this paper puts forward the idea of virtual simulation teaching of clinical laboratory instrument. Based on the training objective of medical laboratory application-oriented talents, the design and management of virtual simulation teaching of single instrument and comprehensive project training are formed. The teaching effect evaluation and quality control method are constructed, which significantly improves the students' autonomous learning ability and the comprehensive practical ability. It further promotes the connotation construction of medical laboratory experiment teaching with the help of Internet sharing advantages.

PEGylated uricase was prepared with the N-terminal amino site-specific modification by periodate oxidation followed by reductive-amination. A monomethoxy poly(ethylene glycol)intermediate was synthesized by amidation from monomethoxy poly(ethylene glycol)amine hydrochloride 20000(mPEG20000-NH2 ·HCl)with the relative molecular mass of 20 kD and N-(tert-butoxycarbonyl)-L-serine(Boc-Ser-OH), and then the Boc group of the intermediate was removed by trifluoroacetic acid(TFA)to produce the desired product Ser-mPEG20000. This compound could be oxidated by periodate to obtain a new poly(ethylene glycol)aldehyde derivative with high activity, which could be used to modify proteins with the N-terminal amino site-specific PEGylation after ultrafiltration, and the modification conditions to uricase by Ser-mPEG20000 were optimized. The structures of poly(ethylene glycol)intermediate and the target product were characterized by IR and 1H NMR, and the overall yield of the target product was 72. 8%. The preliminary modification to uricase indicated that the desired product Ser-mPEG20000 could modify proteins easily and efficiently. The optimal modification conditions of uricase PEGylated by Ser-mPEG20000 were obtained as follows: the molar ratio of Ser-mPEG20000 to uricase was 2 ∶1; the pH value of solution was 5. 0; the reaction temperature was 25 °C and the reaction time was 6 h.

Objective To study the auditory brainstem response (ABR) of normal adult CBA,C57BL,Kunming and 129 mice and analyze the ABR thresholds and latencies in order to obtain normal values and standardized testing process,thereby providing important reference for future auditory hearing research in mouse.Methods Six -week-old normal mice of CBA,C57BL,Kunming and 129(each strain containing 20 ears of 20 mice) were used in this study.ABR test with both the click and tone burst were carried on.The incidence of each wave and the thresholds and latencies of various strains of mice were recorded.Results For these four strains of mice,wave Ⅱ had the highest occurrence rate and was used to determine the thresholds.Four strains of mice all were sensitive to the sound at 8,12,16 kHz,most to 12 kHz.Under anesthesia condition,the latency of each ABR wave prolonged as testing time increase,especially the waves Ⅲ ～ V which reflected the functions of the part near the cerebral center.Conclusion Under anesthesia state,for these four strains of mice,wave Ⅱ has the highest occurrence rate and is used to determine the threshold.We determine the intensity level at which Wave Ⅱ just appeared as the ABR threshold.The stain of CBA mice is the best one to establish an animal model related to hearing function research because ABR of the other three strains are not stable as the CBA mice.Wave SP can reflect the hair cell functions indirectly.

The stability of deoxyribonucleoside triphosphate (dNTP) pool is essential for the normal synthesis of nuclear and mitochondrial DNA. The lack or excess of any dNTP may cause DNA damage and genomic instability, and increase mutation rate. Present studies have confirmed that the instability of dNTP pool is closely related to a variety of tumorigenesis. In addition, dNTP pool is involved in the development of tumor via multiple pathways, while the mechanisms of tumors caused by the instability of dNTP are complicated. This paper discusses the relationship between the stability of dNTP pool and DNA damage repair to provide a theoretical basis for early diagnosis and targeted treatment of tumors.