Cationic colloidal gold (CCG) nanoparticles were used for labeling on the anioinic sites of living cells under two-photon fluorescence (TPF) microscope,and for delivering macromolecules into the target cells when irradiated by focused femtosecond laser pulses. 15 nm CCG nanoparticles which were made by conjugation with poly-L-Lysine,were attached on the anionic sites,especially on the membrane,of CHO-K1 cells because of their strong positive charge at physiological pH. Target cells labeled with cationic gold nanoparticles were imaged under TPF microscope,and lifetime images of the same targets were taken by time correlated single photon counting (TCSPC) technique in order to verify the fluorescence of the marker and the luminescence of the gold particles. The results shown that CCG nanoparticles first accumulated on the negatively charged sites of the membrane,then entered via endocytic pathway and attached anionic sites in plasma. A macromolecular 10 ku fluorescein isothiocyanate dextran (FITC-D) was added into the sample and the focused femtosecond laser of TPL microscope was employed to scan the target cells layer by layer. Typical laser power level used in biological imaging is about 3～5 mW. Here the laser power of scanning was below 5 mW in order to prevent photochemical damage of the fs-pulses alone and to localize effects to the nanoparticles on a nano-scale. After scanning the target cells under stack mode,macromolecular fluoresceins surrounding the cells was observed to cross the membrane and to diffuse in the cytoplasma. Comparing with the images before scanning,the two-photon fluorescence and fluorescence lifetime images revealed the delivery of FITC-D into target cells. Photothermal effects,which may be responsible for the permeabilisation,are highly localized in nanoscale and are not expected to cause damage exceeding the cell membrane. After extensive of laser scanning also cell death occurred. The ratio of the uptake of FITC-D and cellular death under different conditions were measured by flow cytometer. The results shown: with the increased scanning times or ratio of particles to cells,transfer efficiency increased first and decreased afterwards,but the ratio of cellular death went up all along.

Objective To compare the diagnostic value of high frequency ultrasound,mammography and breast blood-oxygen function imaging system in diagnosis of breast masses.Methods The images of 89 breast masses by high frequency ultrasound,mammography and breast blood-oxygen function imaging system were reviewed.The study compared the sensibilities and specificities of the three methods in the masses and analyzed their cause of missed diagnosis.Results The sensitivity of the diagnosis of breast cancer by high frequency ultrasound,mammography and breast blood-oxygen function imaging system were 80.00％,70.00％ and 50.00％,respectively.The specificity of the diagnosis of breast cancer by them were 94.94％,98.73％ and 97.47％,respectively.There were sigmfiacant differences in diagnosis of breast benign lesion among the high frequency ultrasound,mammography and breast blood-oxygen function imaging system.The sensitivity of high frequency ultrasound in detecting fibroadenoma of breast was 98.11％ higher than the other methods.Mammography was insensitive to the benign breast lesions,but its specificity was high.Conclusions High frequency ultrasound,mammography and breast blood-oxygen function imaging system are the highly effective diagnostic tool for breast cancer,but the diagnostic value of mammography and breast blood-oxygen in breast fibroadenoma and in cystic disease of breast aren' t high.Breast blood-oxygen function imaging system can enhance the accuracy of the diagnosis of mammary inflammation.

Objective To study the expression of eukaryotic translation initiation factor 4E(eIF4E)in the pathological scars and its probable role in the pathogenesis of pathological scars.Methods Immunohistochemiscal technique was performed to detect the expression and distribution of eIF4E protein in hypertrophic scars(14 cases),keloids(25 cases),mature scars(20 cases)and normal skins(20 cases).Reverse transcription polymerase chain reaction(RT-PCR)was used to detect the eIF4E mRNA level in hypertrophic scars(7 cases),keloids(8 cases),mature scars(8 cases)and normal skins(8 cases).Results Thepositive rate of eIF4E protein expression was remarkably significant difference between normal scars and pathological scars(P＜0.05).The level of eIF4E mRNA in pathological scars 1.73±0.31was higher than that in control group 0.99±0.28.There was significant difference between two groups (P＜O.05).Conclusions The expression of eIF4E is increased in pathological scar.eIF4 E expression is closely associated with the development of pathological scar.Therefore,eIF4E overexpression may play an important role in the proliferation of fibroblasts and in the pathogenesis of pathological scar.

OBJECTIVE: To study the combined effect of noise and hydrogen cyanide on noise-induced hearing loss( NIHL)in a metal electroplating enterprise. METHODS: The judgment sampling method was used to select 663 workers in a largescale metal electroplating enterprise as the study subjects. Among them,186 workers exposed to noise alone were designated as noise group; 138 workers exposed to hydrogen cyanide alone were designated as hydrogen cyanide group; and161 workers exposed to noise and hydrogen cyanide were designated as combined effect group,and 178 workers without exposure from occupational disease risk factors were designated as control group. Questionnaires survey and pure tone audiometry were used for analyzing the effects of combined noise and hydrogen cyanide exposure on NIHL. RESULTS: The hearing loss detection rate of the study subjects was 40. 4%. The hearing loss detection rates in the control group,noise group,hydrogen cyanide group,and combined effect group were 17. 4%,47. 8%,32. 6% and 64. 0%,respectively. The detection rate of hearing loss in the control group was lower than that in the other three groups( P < 0. 008). The NIHL detection rates in the combined effect group and the noise group were higher than that in the hydrogen cyanide group( P <0. 008). The hearing loss detection rate of the combined effect group was higher than that of the noise group and the hydrogen cyanide group( P < 0. 008). Ordinal multi-categorical logistic regression model results showed that after adjusting confounding factors such as age,length of service,gender,marital status,smoking,alcohol drinking,we found hydrogen cyanide exposure,noise exposure,and combined exposure to hydrogen cyanide and noise had effects on workers' hearing(P < 0. 05). The risk of hearing loss in workers exposed to noise and hydrogen cyanide was higher than that of workers exposed to noise alone or hydrogen cyanide alone. CONCLUSION: There is a combined effect of noise and hydrogen cyanide in this metal electroplating enterprise,which can increase the risk of NIHL in workers.

Objective: Through the study of angiotensinⅡ- type 2 receptor agonist (AT2R) after pretreatment of mechanical ventilation lung injury (VILI) in rats model, to clarify the role of angiotensin Ⅱ - type 2 receptor agonist (C21) in alleviating VILI inflammation and the damage of immune function and its possible mechanism. Methods: In this experiment, the acute lung injury model was established by mechanical spring-volume ventilation in SD rats, and C21 pretreatment was performed to observe the pathological condition of lung tissue in rats with different ventilation duration, and to detect the inflammatory changes of BALF lavage fluid. Flow cytometry was used to detect the CD68+/iNOS+ labeled M1 type AMφ and the CD68+/Arg-1+ labeled M2 type AMφ in alveolar lavage fluid. Results: The mechanical VILI rat model was successfully established. The pathological injury score of the mechanical ventilation 4 h model, the wet/dry weight of lung tissue, the number of cells and protein in BALF lavage fluid were increased significantly, the levels of TNF-α and IL - 1 were increased significantly, the levels of IL-4 and IL-10 were decreased significantly, and the level of inflammatory reaction decreased with the increase of ventilation time. The M1/M2 ratio in the 4 h ventilation model group was the highest, which was significantly different from the control group (P<0.05). Compared to the model group, the C21 pretreatment significantly reduced the levels of proinflammatory factors TNF-αand IL-1, and increased the levels of anti-inflammatory factors IL-4 and IL-10 in BALF (P<0.01). After the intervention of AT2R agonist at 4 h, 6 h and 8 h, the M1/M2 ratio of the model was lower than that of the model without AT2R agonist at 4 h, 6 h and 8 h. Conclusion Mechanical ventilation for 4 h in SD rats can establish a mechanical ventilation lung injury model. AT2R agonist C21 can promote the polarization of macrophages to m2-type, and C21 pretreatment may alleviate VILI inflammation and immune damage by altering the polarization of macrophages.