Seventeen cases of malignant melanoma (MM) were observed with transmission electron microscopy in order to clarify the significance of abberant melanosomes in its diagnosis.30 cases of nevus were also studied to serve as control.It was found that aberrant melanosomes were present in 14 cases of MM including 2 cases of amelanotic MM and absent in 2 cases of pigmented MM and one case of amelanotic MM.In addition,aberrant melanosomes were found in 4 cases of congenital nevus.The findings suggest that the significance of aberrant melanosomes in the diagnosis of MM has been overemphasized.It is believed that the diagnosis of MM must be judged comprehensively on all the ultrastructural changes under transmission electron microscope.

There are controversies concerning whether congential small nevus(CSN)is liable to undergo malignant degeneration and whether it should be resected promptly.The signif-icane of CSN in the pathogenesis of malignant melanoma(MM)was assessed with microspec-trophotometric determination of DNA quantity,the detection of the gene product of N-ras,p21 protein,with ABC technique,ultrastructural study of MM tissue with electron microscopy,and analysis of clinical data of MM.The findings were as follows:(1)The DNA content increased sequentially in order of acquired nevus(AN),CSN,congenital giant nevus(CGN)and MM,and the difference was statistically significant among the 4 groups(P

AIM: To examine the effects of L-carnitine on apoptosis and oxidant injury in cultured neonatal rat cardiomyocytes induced by hypoxia/reoxygenation and its possible mechanism. METHODS: The cultured cardiomyocytes were divided into three groups, control, A/R group (anoxia for 120 min, reoxygenation for 240 min) and L-carnitine treatment group, in which cells were exposed to 20 mg/L, 50 mg/L, 100 mg/L, 200 mg/L L-carnitine respectively at 2 h before anoxia. The superoxide dismutase (SOD), succinate dehydrogenase (SDH) activities and malondialdehyde (MDA) content were examined, and the apoptosis was determined by flow of cytometry (FCM). In addition, the ultrastructure was observed by transmission electron microscopy. RESULTS: In A/R group, SOD and SDH activities were lower, the apoptosis rate and MDA content were higher than those in control group (P

AIM: To examine the effects of L-carnitine on apoptosis in cultured neonatal rat cardiomyocytes induced by hypoxia/reoxygenat ion and its possible mechanism. METHODS: A cell culture model of neonatal rat cardiacmyocytes wa s used. The cultured cardiomyocytes were classified into three groups: control g roup, I/R group (anoxia for 120 min, reoxygenation for 240 min) and L-carnitine group (L-carnitine, which was classified into four different concentrations, was added to the cells 2 h before anoxia). The activities of superoxide dismutase ( S OD), the content of malondialdehyde (MDA) and the apoptosis were determined by f low cytometry (FCM). RESULTS: In I/R group SOD activities were lower, and the apoptos is rate and MDA were higher than those in control group and they were statistica lly significant (P

Objective To investigate the correlation between posterior perianal abscess and thickness of the puborectalis muscle by magnetic resonance imaging.Methods Sixty-three patients with a low-position posterior perianal abscess (the low-position group),44 patients with a high-position posterior perianal abscess (the high-position group) and 46 healthy volunteers (the control group) were enrolled in this study.In the lithotomy position,MRI was performed to measure the thicknesses of the puborectalis muscle at the 5,6 and 7 o'clock positions of the rectum.Results The thickness of puborectalis muscle at 5,6 and 7 o'clock points in the control group was (5.5 ±0.8),(9.0 ±0.7),(5.4 ±0.6) mm,while that in the low-position group was (5.4 ± 0.7),(10.0 ± 0.9),(5.5 ± 0.7) mm,and that in the high-position group was (7.3 ± 1.0),(11.7-1.2),(7.5 ±0.9) mm,respectively.The thicknesses of the puborectalis muscle at the 5,6,and 7 o'clock positions of the rectum in the lithotomy position were compared between the control group and the low-position group.The difference in the thickness at the 6 o'clock position was statistically significant(t =6.492,P ＜ 0.05),but there were no significant differences at 5 and 7 points (t =-0.719,0.633,P＞0.05).The thicknesses of the pubqrectalis muscle at the 5,6 and 7 o'clock positions of the rectum in the lithotomy position were compared between the control group and the high-position group,and the differences were statistically significant at each position (t =9.476,12.875,13.649,P ＜ 0.05).Simultaneously,the differences between the low-position group and the high-position group were statistically significant(t =-11.206,-7.835,-13.361,P ＜ 0.05).Conclusions Magnetic resonance imaging can diagnose perianal abscess in different parts by measuring the thickness of puborectal muscle,which provides strong evidence for early intervention treatment,so as to improve the therapeutic effect and reduce post-operative anal fistula.

Objective To establish and evaluate unstable atherosclerotic plaque model in abdominal aorta induced by cold stress. Methods Sixty male New Zealand white rabbits were randomly divided into three groups:cold stress group fed with high fat diet and followed by balloon induced arterial wall injury of abdominal aorta at week 2 and exposed to cold (4℃) for 1 h per day except for the first postoperative week,balloon-injury group treated by high fat diet plus balloon-injury, control group fed a normal chow without any treatment. Pathological changes of atherosclerotic plaques among these groups were evaluated at 20 weeks. Meanwhile, serum concentrations of blood lipid,oxidized low density protein(ox-LDL),hypersensitive C-reaction protein (hs-CRP)and interleukin (IL)-8 were determined. Results There was no difference in blood lipid level between cold-stress and balloon-injury groups.Serum concentrations of ox-LDL[(56.1 +14.3)mg/L vs.(42.9± 13.8)mg/L],hs-CRP[(149.1+78.3)mg/L vs. (94.5±57.3)mg/L],IL-8 [(97.6±17.9)μg/L vs.(57.5±18.3)μg/L]and macrophage infiltration[(30.9±5.6)％ vs,(18.7±4.8) ％] were significantly higher in cold stress group than in balloon-injury group (t =2.78,6.91,14.94,6.88,all P＜0.05). Higher angiogenesis rate of atherosclerotic plaque in cold-stress group (23/31,74.1％) was observed in comparison with group balloon-injury(5/25,20,0％)(x2=16.26,P＜0.05). Conclusions Establishment of rabbit unstable atherosclerotic plaque model induced by cold stress in synergy with high fat diet and balloon-injury is feasible, which is superior to conventional method through high fat diet plus balloon-injury surgery.

Objective To systematically evaluate the clinical effect of prone position mechanical ventilation on the improvement of oxygenation in patients with severe pneumonia. Methods Pubmed, Embase, Cochrane Library, CNKI, Wanfang Data and VIP database were searched from the time of database built up until December 10th, 2017. All the published randomized controlled trials (RCTs) about the effects of prone position ventilation on the oxygenation of severe pneumonia patients were screened, and were confirmed by the literature reference citation retrieval. Inclusion and exclusion criteria had been used to review and rank the literature. After evaluating the quality of included studies, the data was extracted from RCTs and given a Meta-analysis using RevMen 5.1. Results Twelve RCTs with 650 cases were included. Eleven of them were Chinese literature while 1 was in English. Ten studies showed that the prone position ventilation had a significant influence on improving partial pressure of oxygen [weighted mean difference (WMD) =9.93, 95% confidence interval (95%CI) = 2.92-16.95, P = 0.006], publication bias was found in these studies. Seven studies showed that the prone position ventilation had a significant influence on partial pressure of carbon dioxide (WMD =9.99, 95%CI = 1.81-18.18, P = 0.02), publication bias was found in these studies. Seven studies showed that the prone position ventilation had a significant influence on oxygenation index (WMD = 31.22, 95%CI = 26.06-36.39, P < 0.000 01), publication bias was found in these studies. Two studies showed that the prone position ventilation had a significant influence on oxygen saturation of blood (WMD = 2.12, 95%CI = 1.24-3.00, P < 0.000 01), no publication bias was found in these studies. Conclusion Prone position ventilation can effectively improve the patients' oxygenation index, partial pressure of oxygen, and oxygen saturation of blood, and reduce the partial pressure of carbon dioxide.

Objective To review the clinical-pathological features, the tendency of incidence over 20 years, the predisposing factors, and the differences between the cases of cutaneous malignant melanoma from two hospitals. Methods A collection of 305 cases diagnosed as cutaneous malignant melanoma, among which 185 cases had complete clinical-pathological data, during 1981-2000 was analyzed. Results Acral malignant melanoma accounted for 63.3%, and the cases associated with congenital small nevi at the primary site accounted for 15.8% of 305 patients. During the period 1981-1990 and 1991-2000, cutaneous malignant melanoma constituted 0.053% and 0.094%, respectively, of all diagnoses with pathological sections, with an growth rate of 3.9% yearly. There was a tendency of the increased lesions located on face and neck, and decreased lesions on acra, over 20 years. Conclusion A rise of diagnosis of cutaneous malignant melanoma has been noticed from two hospitals over 20 years. Acra, especially planta, is the predominant anatomical site of cutaneous malignant melanoma.

ObjectiveTo systematically evaluate the safety of interferon β-1a for treatment of corona virus disease 2019 （COVID-19）， and to provide references for interferon β-1a's clinical application. MethodsThis study was conducted with the database from US Food and Drug Administration adverse event reporting system （FAERS） from January 1， 2015 to March 31， 2021. Information component （IC） and reporting odds ratio （ROR） methods were applied for signal mining. ResultsA total of 463 700 records of COVID-19 were selected for analysis， and 45 positive drug adverse event signals were detected. Headache （IC₀₂₅=1.09， ROR₀₂₅=2.28）， pyrexia （IC₀₂₅=0.51， ROR₀₂₅=1.51） and multiple sclerosis relapse （IC₀₂₅=3.67， ROR₀₂₅=14.71） were positive adverse events with higher frequency. Autoimmune disorder （IC₀₂₅=4.42， ROR₀₂₅=24.03）， streptococcal infection （IC₀₂₅=4.12， ROR₀₂₅=19.82）， and multiple sclerosis relapse （IC₀₂₅=3.67， ROR₀₂₅=14.71） were positive adverse events. Acute lung injury， cardio-respiratory arrest and metabolic acidosis were associated with a higher proportion and frequency of death. ConclusionThere are certain safety issues with interferon β-1a in the treatment of COVID-19， and some adverse events with high frequency and high death rate deserve further attention by medical staffs.