Objective To investigate the clinical value of the procalcitonin (PCT)measurement in preventing the occurrence of the bacterial drug resistance and reducing the overuse of antibiotics.Methods 400 inpatients without thyroid dysfunction but with suspected bacterial infections in our hospital from June 2012 to April 2013 were screeded out.Under the patient′s informed consent and the allowable condition,the routine treatment group (200 cases )and the PCT guidance group(200 cases )were obtained. Then,the antibiotic use time,hospitalization duration and hospitalization expenses were retrospectively anlyzed in the two groups. Meanwhile,the PCT guidance group was dynamically monitored.Results The mean antibiotic therapeutic time in the PCT guidance group was shorter than that in the routine treatment group;the average hospitalization days had statistical difference between the two groups (P<0.001 );the antibiotic expenses accounted for 26.4% and 32.0% of the hospitalization medication costs,which also had statistically significant difference (P <0.001).The clinical pulmonary infection scores(CPIS)were not compared because of lacking microbiology indicators.During the dynamic monitoring,when PCT<0.10 ng/mL,the antibiotic use was stopped,when PCT≥0.25 ng/mL,the antibiotic use was restored,when PCT≥0.25 ng/mL or≥0.50 ng/mL for consecutive 3 d,adjusting the antibiotics,dose or administrating route obtained significantly therapeutic effect,which indicating that PCT could be used for the prognosis judgement of the disease.Conclusion The once measurement of serum PCT could guide for diagnosing and assessing the infection degree,while its continuous measurement could guide the antibiotic use and make the prognosis on the disease condition.

Objective To further confirm the clinical value of serum total bile acid (TBA) in hepatic lesion in patients with hemolytic disease of the newborn.Methods Enzyme circulation assay was applied to measuring in 68 patients with hemolytic disease of the newborn. Total bilirubin (TBIL), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and γ-glutamyltransferase (GGT) were measured simultaneously.Results The serum level of TBA was (27.63±4.83) mmol/L in haemolysis group, significantly higher than that in control group (14.92±6.87) mmol/L (P<0.01). The positive rate accounted for 70.59% (48/68) in haemolysis group, and serum level of TBA was positively correlative with liver functional parameters (TBIL, ALT, GGT and ALP).Conclusion Serum TBA may be used as an indicator of therapeutic effect monitoring and prognosis evaluation of hepatic lesion in patients with hemolytic disease of the newborn.

Objective To explore the clinical value of combined detection of lysophosphatidic acid(LPA),tumor-specific growth factor(TSGF)and carbohydrate antigen 1 9-9(CA1 9-9)in the diagnosis of non-small cell lung cancer(NSCLC).Methods The ser-um levels of LPA,TSGF and CA1 9-9 in 97 cases of patients with NSCLC(NSCLC group),43 cases of patients with benign lung disease(benign lung disease group)and 50 cases of healthy individuals(healthy control group)were detected,and diagnostic value of combined detection of these three tumor makers in the diagnosis of NSCLC was analysed.Results Serum levels of LPA,TSGF and CA1 9-9 in the NSCLC group were significantly higher than those in the benign lung disease group and healthy control group,had statistically significant differences(P <0.05).The sensitivity and specificity of combined detection of LPA,TSGF and CA1 9-9 was 68.63% and 37.1 7% respectively,and the sensitivity was higher than that of single detection and combined detection of any two of the three indicators.Conclusion Combined detection of tumor markers can improve the sensitivity in the diagnosis of NSCLC, which could provide reliable laboratory references for diagnosing NSCLC.

Objective To study feasibility in extraction of calcific sign within pulmonary nodules with pattern classification.Meth-ods 49 cases with pulmonary nodules (benign in 16 and malignant in 33)confirmed by pathology or clinical follow-up were included in this study and all cases underwent chest CT examinations.CT images were interpreted double-blind by two associate chief radiolo-gists to draw a conclusion that there were any calcification within pulmonary nodules.Meanwhile,the calcifications in the regions of interest(ROI)on CT images were estimated with extraction of the sign of gray value,geometric and lung markings in ROI,and based on pattern classification algorithm at supporting vector machine(SVM).Results According to the results assessed by senior radiologists for classification within pulmonary nodules,the area under ROC curve was 0.95 which was extracted by automatic pat-tern classification algorithm,the extraction performance was stable(k=1),and was goodness fit with visual observation by doctors (k=0.939).Conclusion The ability of automatic pattern classification in detecting calcification within pulmonary nodules is about the same as that of visual assessment by senior doctors.

Objective:To systematically review the severe risk in common chronic diseases and coronavirus disease 2019 (COVID-19) cases.Methods:PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database, China Biology Medicine disc, medRxiv, SSRN and ChinaXiv were searched for clinical and epidemiological studies that reported chronic diseases in patients with COVID-19. Only studies of severe COVID-19 in comparison with non-severe controls were included. The prevalence rates of chronic diseases including chronic obstructive pulmonary disease (COPD), diabetes mellitus, hypertension, malignant tumor, cardiovascular diseases, cerebrovascular disease, chronic kidney disease, and chronic liver disease were estimated. Pooled odds ratio ( OR) with 95% confidence interval ( CI) between patients with severe COVID-19 and non-severe groups were calculated. R 3.6.3 software was used for meta-analysis. Results:The search yielded 2 455 articles. A total of 19 eligible comparative studies with 4 792 patients were included in a quantitative analysis. Meta-analysis showed that there was a proportion of 55.0% (95% CI 40.0%-80.0%) male among patients with COVID-19, and the overall pooled prevalence of any chronic diseases in COVID-19 cases was 30.4% (95% CI 24.0%-37.0%). The most prevalent comorbidity was hypertension (16.9%(95% CI 14.0%-20.0%)), followed by diabetes mellitus (8.3%(95% CI 8.0%-9.0%)). The proportion of male patients with severe COVID-19 was higher than that of male patients with non-severe COVID-19 (64.4% vs 52.8%, OR=1.49, 95% CI 1.08-2.05, Z=4.63, P<0.01). The prevalence rates of COPD, cerebrovascular disease, diabetes mellitus, chronic kidney disease, hypertension, cardiovascular diseases and malignant tumor in severe COVID-19 patients were higher than those of non-severe patients ( OR=5.77, 95% CI 3.80-8.74; OR=4.47, 95% CI 2.71-7.38; OR=3.55, 95% CI 2.86-4.40; OR=3.05, 95% CI=1.76-5.28; OR=2.82, 95% CI=1.96-3.97; OR=2.39, 95% CI=1.77-3.23; OR=2.15, 95% CI 1.27-3.66, respectively, Z=8.37, 6.01, 11.60, 4.20, 5.46, 5.71, 3.12, all P<0.01). There was no significant difference in the prevalence of chronic liver disease between severe and non-severe patients ( OR=1.35, 95% CI 0.84-2.17, P=0.11). Conclusion:COVID-19 patients with chronic diseases have higher risk of developing severe disease, and the ORs from high to low are COPD, cerebrovascular disease, diabetes mellitus, chronic kidney disease, hypertension, cardiovascular diseases and malignant tumor.

Objective: To construct and identify a mouse model with conditional knockout (cKO) of p75 neurotrophin receptor (p75NTR-cKO) gene in epidermis cells by Cre-loxP system. Methods: Five p75NTR^flox/flox transgenic C57BL/6J mice (aged 6-8 weeks, male and female unlimited, the age and sex of mice used for reproduction were the same below) and five keratin 14 promotor-driven (KRT14-) Cre^{+ /-} transgenic C57BL/6J mice were bred and hybridized via Cre-loxP system. Five p75NTR^flox/+ ·KRT14-Cre^{+ /-} mice selected from the first generation of mice were mated with five p75NTR^flox/flox mice to obtain the second generation hybrids. After the second generation mice were born 20-25 days, the parts of the mice tail were cut off to identify the genotype by polymerase chain reaction method. Four p75NTR gene complete cKO mice (6 weeks old) and 4 wild-type mice (6 weeks old) were selected and sacrificed respectively. The abdominal skin tissue and brain tissue were excised to observe the expression of p75NTR in the two tissue of two types of mice by immunohistochemical staining. The abdominal skin tissue of two types of mice was obtained to observe the histomorphological changes by hematoxylin and eosin staining. Results: (1) Twenty second generation mice were bred. The genotype of 4 mice was p75NTR^flox/flox·KRT14-Cre^{+ /-}(p75NTR^-/-), i. e. p75NTR gene complete cKO mice; the genotype of 5 mice was p75NTR^flox/+ ·KRT14-Cre^{+ /-}, i. e. p75NTR gene partial cKO mice; the genotype of 5 mice was p75NTR^flox/flox·KRT14-Cre^-/-, and that of 6 mice was p75NTR^flox/+ ·KRT14-Cre^-/-, all of which were wild-type mice. (2) The expression of p75NTR was negative in skin epidermis tissue of p75NTR gene complete cKO mice, while numerous p75NTR positive expression was observed in skin epidermis tissue of wild-type mice. Abundant p75NTR positive expression was observed in brain tissue of both wild-type mice and p75NTR gene complete cKO mice. (3) There was no abnormal growth of skin epidermis tissue in both wild-type mice and p75NTR gene complete cKO mice, with intact hair follicle structure. Conclusions Applying Cre-loxP system can successfully construct a p75NTR-cKO mice model in epidermis cells without obvious changes in skin histomorphology.