Polychlorinated biphenyls(PCBs) is one of persistent organic pollutants which are widely exist in environment.This review described PCBs characteristics and toxicity on animals and human livers.Before now,it was identified that PCBs caused liver damage and hepatocarcinogenicity for animals.However,occupational studies and long-term,low level exposure studies to human beings have found no direct correlation between PCBs exposure and liver damage and carcinogenicity,only accidental environmental exposures have found increased mortality of liver disease.But high morbidity of human liver cancer and detected PCBs in the environment were reported in some regions.It is evident that more researches should be done.

BACKGROUND:Clinical studies have shown that early use of methylprednisolone can promote neurological functional recovery, reasonable initial dose, interval time and treatment duration are the key to the methylprednisolone treatment of acute spinal cord injury. OBJECTIVE:To observe the differential protein expression profile in spinal cord tissue after intrathecal injection of high-dose methylprednisolone was given in rat model of acute spinal cord injury. METHODS:Eight Sprague-Dawley rats were included in this study to establish acute spinal cord injury model and the models were randomly divided into two groups, receiving intrathecal injection of methylprednisolone 7.5 mg/kg at 0 and 8 hours after modeling. The injured spinal cord tissue was harvested after 24 hours of injection. The differentialy expressed proteins and nerve regeneration-related differential proteins in two groups were analyzed using isotope labeling and quantitative technical analysis. RESULTS AND CONCLUSION: Totaly 87 differentialy expressed proteins were identified in this study. Compared with 0 hour group, there were 43 up-regulated differential proteins and 44 down-regulated differential proteins in the 8-hour group. Eighteen differential proteins were related to neural regeneration, including 8 up-regulation proteins and 10 down-regulation proteins. OMgp as a potential neural axon growth inhibitory factor specificaly bound with NgR/P75/TROY/Lingo-1 to form receptor complexes and activated RhoA through the second messenger cAMP, thus inhibiting the colapse of axon growth cone. Folowing intrathecal injection of methylprednisolone for treatment of acute spinal cord injury in rats, differential proteins and nerve regeneration-related factors in spinal cord are identified and analyzed for protein database retrieval and protein function analysis, their expression may serve as the indicator of monitoring nerve regeneration after acute spinal cord injury.

AIM To investigate the curative effects of Kuntai Capsules (Coptidis Rhizoma,Scutellariae Radix,Asini Corii Colla,etc.) on rat model for primary ovarian insufficiency (POI) caused by 4-vinylcyclohexene diepoxide (VCD).METHODS Seventy-five weaned 21-day old rats were divided equally into five groups randomly:control group,model group,low-,medium-,and high-dosage Kuntain group.Except the control group was given sesame oil rats,other four groups were given intraperitoneal injection of VCD solution.According to vaginal smear of rats,eight rats in each group were selected,the levels of FSH (follicle-stimulating hormone),LH (leuteinizing hormone),E2 (estradiol) and AMH (anti-Mullerian hormone) were measured,and morphological changes of ovary and uterus were observed.RESULTS Compared to the control group,FSH level in rats' serum of the model group significantly increased while AMH and E2 levels significantly decreased,and LH level rose;Kuntai Capsules significantly decreased FSH level while increased AMH level;The wet weight of rats' ovary in the model group was lighter than that in the control group.The ovary weight of Kuntai Capsules low-dosage group was increased;the number of follicles at all levels and corpora lutea of rats in the model group were decreased.After the treatment with Kuntai Capsules,the number of follicles at all levels and corpora lutea were increased;light microscopy manifested decreased uterine glands of the tube wall,reduced glandular cavity.After the treatment with Kuntai Capsules,the number of uterine glands increased and the gland cavity expanded.CONCLUSION Kuntai Capsules may slowdown the functional decline rate of ovarian.

Objective:To analyze the categories, scoring methods and effects of dietary patterns in heart failure patients, systematically.Methods:The databases such as Medline, Embase, and Cochrane were searched to obtain articles on dietary patterns of heart failure patients up to December 31, 2019. Arksey and O′Malley's scoping review method was applied to analyze the articles.Results:A total of 1 500 studies were identified, 21 of them met the inclusion criteria. These studies mainly studied Mediterranean diet(11 articles), Dietary Approaches to Stop Hypertension Diet(7 articles), Palaeolithic diet(1 article), low fat diet(1 article), High-protein Diet(1 article).Conclusions:The Mediterranean and DASH dietary patterns have a positive protective effect on heart failure disease prevention and treatment, but more randomized controlled trials are needed to improve the reliability of the conclusions.

Objective To investigate the expression of β-catenin and Oct-4 in colonal carcinoma and explore the relationship with recurrence and metastasis after operation. MethodsImmunohistochemical analysis was used to evaluate the expression of β-catenin and Oct-4.The correlation of β-catenin and Oct-4 expression with tumor cell differentiation,T stage,N stage and metastasis was analyzed.The gene expression of Oct-4 was examined by RT-PCR in 20 frozen tumor tissues and normal tissues adjacent to tumor.Results Thirty-five patients had metastasis. The positive rates of β-catenin and Oct-4 expression were significantly higher in metastasis group than in the non-metastasis group (65.71％ vs 31.11％,51.43 ％vs 13.33 ％,x2 =9.843,P =0.002,x2 =13.605,P =0.001).Expression of β-catenin and Oct-4 was not associated with differentiation,T stage or N stage.The positive expression rate of Oct-4 in colonal carcinoma tissues was significantly higher than that in normal tissues.Metastatic rates in patients with positive expression of β-catenin and Oct-4 was higher than that in negative expression.The survival analysis showed that time of metastasis was significantly different in two groups of patients (P ＜0.05).Conclusion The expression of β-catenin and Oct-4 in tumor tissues is related to metastasis of colonal cancer after surgery and might be used to predict metastasis of colonal cancer after operation.

Objective To assess the efficacy and safety of 800 nm diode laser for removing unwanted hair of Ⅲ-Ⅴ skin type.Methods A total of 114 patients were treated with 800 nm diode laser on 234 sites.Four sessions were performed at an interval of 6-8 weeks.Percentage of hair reduction was evaluated 3 months after each session by comparing the terminal hair count to the baseline values.Follow-up was performed 6-8 months after the last session.In addition,subjective satisfaction of physicians and patients was evaluated according to a four-grade scale and the satisfaction rates were calculated.Results After fouth session,97.01％ of patients had more than 40 ％ hair reduction,and 83.33 ％ patients had more than 60 ％ hair reduction.Hyperpigmentation was observed on 15 (6.41％) sites,and disappeared after 6-8 months follow-up.The satisfactory rates of the physicians and the patients were 98.25 ％ and 96.12 ％,respectively,with no statistical difference (x2 =3.33,P＞0.05).Conclusions 800 nm diode laser for removing unwanted hair of Ⅲ-Ⅴ skin type is a safe and effective treatment option for hair removal,with relatively less side effect.

Objective To explore and evaluate the total oxidative and antioxidant status and lipid levels in patients with COPD. Methods Measurement and comparative analysis were preformed between 51 cases of COPD patients and 45 healthy people in serum TOS,TAS,IMA concentration,blood lipid,and the concentration of ox-LDL. Results In the COPD group,serum IMA concentration was significantly higher than those in the control group(0.94 ± 0.31 vs. 0.62 ± 0.25,P<0.001). The serum TOS was higher than that in the control group(6.51 ± 4.85 vs. 4.53 ± 3.81,P<0.05). The serum ox-LDL concentration in COPD group increased significantly compared with the control group(5.91 ± 3.61 vs. 4.51 ± 2.05,P<0.05). The serum HDL concentration in the COPD group was significantly lower than that in the control group(36.49 ± 9.60 vs. 44.19 ± 10.14,P<0.001). There was no sig-nificant difference in TAS,triglyceride and low LDL between the two groups. Conclusions The serum levels of TOS,ox-LDL and IMA are significantly increased in COPD patients compared with the control group,while HDL-C concentration is significantly decreased. Increase of IMA and ox-LDL in serum of patients with COPD may be relat-ed to imbalance of TOS and TAS due to chronic inflammation and oxidative stress.

Objective To assess the relative value of individual positions in the functional departments of a general hospital in Beijing,for reference of improving the salary allocation system and fine management of human resources.Methods The expert consultation method and International Position Evaluation system were used to quantitatively assess the tasks,work difficulty,size of responsibility and the qualifications required for every.Results A total of 38 experts contributed to this research which studied 140 positions including all functional departments of this hospital.The department having the most positions is the finance department(17)and the least is the Youth League committee(1).The position scoring the highest(805)was the director of medical affairs department;that scoring the lowest(263)was the food and beverage service positions of the diet and nutrition department.There was an evident turning point at score 547.Conclusions Functional departments′ position setting of this hospital proves reasonable,and the assessment scoring can reflect the value of the position in related dimensions.The result can be used as reference indexes for the hospital to perfect its human resource management system and improve the remuneration precision.

Objective To study the effective correction for concealed penis after being operated by circumcision.Methods A total of 16 concealed penis patients underwent circumcision were corrected by improved Brisson's operation,and the treatment effects were observed.Results Shapes of penis were recovered totally or nearly in 16 cases.Five cases appeared serious edema of the penis,but recovered from 3-6 months.The penises were all developed normal without problem of retraction or curvature in 1-2 years of follow up.Conclusion Improved Brisson's operation for concealed penis is an effective remediation for concealed penis after mistherapy by circumcision.

Objective To study the effect of hypoxial endothelia cell conditional medium(HECCM)on the proliferation of pulmonary arterial muscle cell(PASMC).Methods MTT assay was used to test the proliferation,immuno-cytochemistry was used to identify the expression of ?-SM-actin.Results(1)HECCM could promote the proliferation of PASMC,down-regulate their expression of ?-SM-actin.(2)DDPH could up-regulate the expression of ?-SM-actin in PASMC which was time-dependant.Conclusions DDPH could reverse the phenotype transformation of PASMC exposed to HECCM,the action was time-dependant.After some time DDPH could reversly transform PASMC to the normal contractile phenotype.