OBJECTIVE:To study the identification problems of pharmacokinetic compartment models.METHODS:Problems of the identification of classical compartment models in single administration were systematically discussed by Laplace transformation method.RESULTS:The classical compartment models in single administration don't have the character of u-niqueness and the identification for which is a problem.CONCLUSION:The drug level in plasma and the concentration of drugs that distributed in organs were in a direct ratio under the condition of two kinds of unidentifiable classical compartment models,in that case,it has theoretic bases and significance to predict the concentration of drugs that distributed in organs or target organs by means of determining the drug concentration in plasma;if on the other hand,if two kinds of classical com-partment models are identifiable,the drug level in plasma and the concentration of drugs that distributed in organs or target organs wouldn't be in a proportional relationship,in this case,it is advisable to make sure the relationship between the drug le_ vel in plasma and the concentration of drugs that distributed in organs or target organs before predicting drug concentration that distributed in organs or target organs by means of monitoring the drug concentration in plasma;otherwise,it is baseless and meaningless.

Abodominal giant incisional hernia is the common complication of abdominal operations,and surgery is the only efficient treatment for it.It is important to treat the local complications,to use antibiotics and to assess the tolerance of increased intra-abdominal pressure before operation.Component separation technique is feasible to close the abdominal wall defect,which is one of the main difficuhies in giant heruia repair.After that,mesh repair with biological materials is recommended to enhance the abdominal wall.Although mesh repair techniques diversified,sandwich hernionhaphy seems superior.This paper will analyse the present treatment progress of abdominal giant incisional hernia.

Objective To investigate the potential factors that may be associated with clinical significant endoscopy findings (CSEF) and the characters of the appropriate patients for upper endoscopy.Methods Information of the out-patients was collected from the questionnaires that were performed before undergoing upper endoscopy from 26 September 2011 to 23 December 2011,including demographics characteristics,symptoms,gastroesophageal reflux disease questionnaire (Gerd Q) score,comorbidities,medication and purpose for upper endoscopy.The analyses were performed by Logistic regression to find the potential factors that were associated with CSEF.Results A total of 942 cases were enrolled.There were 471 (50.0％) patients with dyspepsia and reflux symptoms,300(31.8％)patients with dyspepsia and without reflux symptoms,and 86(9.1％)patients with reflux symptoms and without dyspepsia.Sum to 325 (34.5％) patients were diagnosed with CSEF,119(12.6％) with erosive esophagitis,28(3.0％) with Barrett esophagus,102 (10.8％)with peptic ulcers,66 (7.0％) with gastric dysplasia,and 13 (1.4％) with upper malignancy.Multivariate Logistic regression analysis showed that men (OR=1.677,95％CI:1.148 to 2.451),older age (OR=1.032,95％CI:1.021 to 1.044),alcohol intake (OR=1.761,95％CI:1.068 to 2.903),Gerd-Q score increase (OR=1.079,95％ CI:1.003 to 1.160),and presence of acid regurgitation (OR=1.659,95 ％CI:1.143 to 2.408) were significantly associated with increasing risk of diagnosis for CSEF,while taking proton pump inhibitors (OR=0.298,95％CI 0.109 to 0.818)was associated with lower possibility of detection.Conclusions Factors such as male,older age,alcohol intake,Gerd-Q score increase,presence of acid regurgitation and taking proton pump inhibitors,may have a certain significance for screening out patients and further improving the cost efficiency of gastroscopy.

Radiotherapy plays a significant role in the treatment of lung malignant tumor.However,as the most main complication of radiotherapy used to treat lung malignant tumor,radiation-induced lung injury is an important influencing factor in impeding further and higher dose radiotherapy.Previous studies show that mesenchymal stem cells (MSCs) have the characteristics of self-replication,multiple differentiation,immunoregulation and directional migration. MSCs can help to repair many kinds of acute and chronic lung injury,meanwhile stem cell transplantation stimulates production of many cytokines to attenuate acute lung injury.So stem cell therapy provides a new kind of thinking in the prevention and treatment of radiation-induced lung injury.

Objective To study the changes in and correlations between the partial pressure of end-tidal carbon dioxide (PETCO2) and the coronary perfusion pressure during cardio-pulmonary resuscitation (CPR) based on the cardiac arrest dog models of ventricular fibrillation by electric shock. Methods 36 healthy dogs were evenly randomized into 3 groups including 4 minutes close-chest CPR(CCCPR) group, 4 minutes open-chest CPR(OCCPR) group, and 8 minutes OCCPR group. There were 12 dogs in each group, half male and half female. In the process of CPR, all parameters about PETCO2 and CPP were recorded. Results In the 4 minutes CCCPR group, the correlation coefficient between the CPP and the PETCO2 was 0.992 (P<0.05), which was in positive linear correlation. In the 4 minutes OCCPR group, the correlation coefficient between the CPP and the PETCO2 was 0.937 (P < 0.05), which also showed positive linear correlation. In the 8 minutes OCCPR group, the correlation coefficient between the CPP and the PETCO2 was 0.952 (P<0.05), and was also in positive linear correlation. The percentage of ROSC was 66.7(8/12) in the 4 minutes CCOPR group, 100%(12/12) in the 4 minutes OCCPR group and 58.3%(7/12) in the 8 minutes OCCPR group. There were statistical differences in CPP, PETCO2 between models with ROSC and without ROSC at 1, 2, 5, 10, 15 and 20 mins of CPR (all P<0.05). Conclusions This research shows that there is a close positive linear relationship between the coronary perfusion pressure and the PETCO2, and PETCO2 could be used to evaluate the prognosis of the CPR.

The pathogenesis of drug-induced Iiver injury( DILI)remains uncIear. AccumuIating evidences in recent years showed that immunoIogicaI factors pIay important roIe in the pathogenesis of DILI. In this articIe,we summarized recent studies on immunoIogicaI factors invoIved in pathogenesis of DILI and compared the immunity mediated DILI with drug induced autoimmune hepatitis. The advances in study on immunoIogicaI factors in DILI wiII have significant impact on prevention and treatment of DILI and autoimmune hepatitis.

Objective To analyze the causes and results of treatment of periprosthetic femoral frac-tures after total hip arthroplasty and to explore the best operative methods for fractures. Methods 11 cases treated for periprosthetic femoral fracture after total hip arthroplasty were subjected to a retrospective fol-low-up study from December 1998 to March 2003. There were 8 men and 3 women, the mean age was 56 years (range, 43 to 75 years). There were 2 Vancouver A type fractures, 7 B2 type, 1 B3 type, 1 C type. 5 fractures were treated by nonoperative methods and other 6 by operative methods, including one fracture malunion treated initially by skin traction. There were 5 revisions using long stem supplemented with cortical allograft strut, including 4 uncemented stems with distal fixation and one cemented stem; the remaining one fracture treated by open reduction and internal fixation. Results None was lost for follow-up. The mean follow-up period was 25.6 months (range, 7 to 50 months). 9 fractures united at a mean of 4 months (range, 3 to 6 months). Nonunion was found in 2 fractures, both were treated nonoperatively. All the 6 fractures treated by operative methods united. Up to now, 7 stems were well-fixed, continuous radiolucent line was seen in one revision case, 3 stems were loosened. The function of the patients with well-fixed stems was bet-ter than those with loosened stems, the mean Harris score of the former was 91. All the cortical allograft struts were incorporated with host bone within one year. No strut fracture happened. Conclusion Type A fractures with well-fixed stems can be treated by nonoperative methods, while type B1 and type C fractures should be treated by open reduction and internal fixation, on condition there is no surgical contraindication. For fractures with loosened stems, use of an uncemented long stem with distal fixation supplemented with cortical allograft strut is the best choice.

H295R cells can express all the key enzymes involved in the synthesis of steroid hormones,and have the ability to produce the steroid hormones found in the adult human adrenal cortex. Good correlation of response to toxicity has been reported between H295R cell line and normal adult human adrenal cells. H295R cell line can be used to evaluate effects of chemicals on gene expression,enzymatic activities and hormone production,and to explore the mode of action of chemicals on steroidgenesis. H295R cell line has been suggested as a potentially useful tool for screening environmental steroid hormone disruptors in vitro. The application of H295R cell line for screening environmental steroid hormone disruptors in vitro and its current issues are reviewed in this article.

Non-vascular interventional diagnostic methods of thyroid nodules include ultrasonography-guided fine-needle aspiration cytology(USgFNAC)and ultrasonography-guided core-needle biopsy(USgCNB).USgFNAC is a practical method used to select and to guide the treatment of various thyroid nodules, however, it is difficult to make a differentiation between benign and malignant lesions simply to rely on the findings of a small number of cells.USgCNB has the advantage of being able to obtain satisfactory specimen enough for making a histological diagnosis, although this procedure is contraindicated in some patients.Non-vascular interventional treatments of thyroid nodules include percutaneous ethanol injection(PEI) and ultrasonography-guided interstitial laser photocoagulation(USgILP).Both PEI and USgILP have fine effect on the benign thyroid nodules.Compared with PEI, laser-induced necrosis can be well controlled, thus, the adverse reactions, such as the formation of fibrosis adjacent to the nodule, vocal cord paralysis, etc.can be avoided.Non-vascular interventional treatments may cause some untoward effects.For the diagnosis and treatment of thyroid nodules, the non-vascular interventional procedure is simple, safe, effective and economic with less complications, therefore, this technique is worth being popularized in clinical practice.

Objective: To evaluate the nutritional status of gastrointestinal carcinoma patients by mini-nutritional assessment(MNA),and to compare the relationship with different tranditional evaluative methods. Methods: The nutritional state and the malnutritional incidence were analysed by MNA questionnaire in 496 gastrointestinal carcinoma patients,and the relationship among MNA score and anthropometric measurements and laboratory test was studied.Results: ①According to the scores of MNA, 16.94%(84/496) patients were of mal-nutrition and 42.54%(211/496) patients were at risk of malnutrition.② In terms of each single index,BMI,TSF,AC and AMC,the prevalence of malnutrition was 13.5%,21.9%,15.1% and 15.5% respectively.③According to laboratory test,including serum albumin,PA,TLC,the incidence of malnutrition was 14.9%,25.4% and 30.8%.④ There was a significant correlation between the MNA score and tranditional nutritional estimated markers.The correlation coefficients of MNA with BMI,ALB,AC,TSF,AMC and TLC were between 0.18 and 0.53(P