大气中不同粒径颗粒物诱导人羊膜FL细胞UDS的研究

本研究以诱导人羊膜细胞ＵＤＳ为指标，对太原市大气不同粒径的颗粒物提取液进行了致突变性检验，结果表明，不同粒径颗粒物的提取液均可产生一定的遗传毒性，尤以３．３μｍ以下的颗粒物的遗传毒性较强。     

输尿管镜气压弹道碎石治疗输尿管结石(附108例报告)

目的探讨输尿管镜气压道弹碎石术治疗输尿管结石的临床疗效.方法在输尿管镜窥视下采用气压弹道碎石机对108例输尿管结石进行治疗.结果 103例原位碎石成功,总成功率95.3%,其中输尿管上段结石成功率为83.3%,中段结石为96.3%,下段结石为98.4%.平均碎石时间(4.5±2.2)min,术后1～3个月结石排净率100%.结论输尿管镜气压弹道碎石术治疗输尿管结石具有安全、有效、容易操作等特点,是治疗输尿管结石的首选方法.     

Na原子Rydberg态能级寿命的计算研究

利用一不依赖于实验参数的理论方法计算了钠原子Rydberg态的能级寿命，计算结果很好地符合已有的实验值及其他理论计算值，此计算方法较为严格并且可以弥补实验的不足。     

细菌性痢疾季节性高峰变化及其与气温关系的研究

目的 探讨气温对细菌性痢疾发病的影响。方法 应用相关回归统计法和圆形分布法对资料进行研究。结果 菌痢的月平均发病百分构成比与相应年份月平均气温呈正相关(r=0.5099,P<0.01);辖区近10年的平均气温较前10年有所上升,尤其秋冬季与初春月平均气温升高了1℃左右,而菌痢发病高峰时点明显后移(F=11.49,P<0.01),流行高峰期也有后移倾向。结论 气温对菌痢的发病有直接影响,气温升高,菌痢的发病增加,年平均气温升高可导致菌痢的发病高峰时间后移。     

Lifetime and six-month prevalence of mental disorders in the Munich follow-up study

Summary The Lifetime and 6 month DSM-III prevalence rates of mental disorders from an adult general population sample of former West Germany are reported. The most frequent mental disorders (lifetime) from the Munich Follow-up Study were anxiety disorders (13.87%), followed by substance (13.51%) and affective (12.90%) disorders. Within anxiety disorders, simple and social phobia (8.01%) were the most common, followed by agoraphobia (5.47%) and panic disorder (2.39%). Females had about twice the rates of males for affective (18.68% versus 6.42%), anxiety (18.13% versus 9.07%), and somatization disorders (1.60% versus 0.00%); males had about three times the rates of substance disorders (21.23% versus 6.11%) of females. Being widowed and separated/divorced was associated with high rates of major depression. Most disordered subjects had at least two diagnoses (69%). The most frequent comorbidity pattern was anxietyand affective disorders. Simple and social phobia began mostly in childhood or early adolescence, whereas agoraphobia and panic disorder had a later average age of onset. The majority of the cases with both anxiety and depression had depression clearly after the occurrence of anxiety. The DIS-DSM-III findings of our study have been compared with both ICD-9 diagnoses assigned by clinicians independently as well as other epidemiological studies conducted with a comparable methodology.     

Oxygen Tension Imaging in the Mouse Retina

A newly developed microscope-based imaging system was used to measure the oxygen tension (PO₂) inside the retinal and choroidal vessels of mice and to generate in vivo maps of retinal PO₂. These maps were generated from the phosphorescence lifetimes of an injected palladium–porphyrin compound using a frequency-domain measurement. The system was fully calibrated and used to produce retinal PO₂ maps at different inspiratory oxygen fractions. PO₂ rose accordingly and predictably as inspiratory O₂ was stepped from hypoxic to hyperoxic conditions. Important experimental and acquisition parameters necessary for applying phosphorescence lifetime imaging to the mouse eye were investigated, including camera exposure and intensifier gain settings. Because of a need to limit light exposure to the retina, PO₂ map quality as measured by the coefficient of determination was investigated as a function of signal-to-noise and accumulated excitation energy deposition. With the development of this technology for use in mice, the potential for investigating the oxygen dynamics in genetically engineered mouse models of retinal disease, including diabetic retinopathy, glaucoma, and age-related macular degeneration, is advanced. © 2003 Biomedical Engineering Society. PAC2003: 4266Ew, 8763Lk, 8719Dd     

The role of carbon dioxide and atmospheric air in double-contrast barium enema

Background Patient discomfort 0–24 h after double-contrast barium enema (DCBE) was investigated in two ways.Methods In part 1, 139 patients, not previously informed, were contacted by telephone to assess symptom rates without bias. In part 2, designed as a prospective randomized double-blind trial, the effect of carbon dioxide (CO₂) as an insufflating gas was compared with conventional atmospheric air (AA).Results Part 1: 10% experienced severe abdominal pain, and 18% severe abdominal distention. Part 2: Low discomfort rates were found for both severe pain (7% for AA vs. 2% for CO₂) and severe distention (13% for AA vs. 8% for CO₂); the differences were not significant. In both parts of the study, female patients with a history of abdominal discomfort of colon irritabile type were significantly overrepresented in the severely symptomatic groups. Equal numbers of patients experiencing severe abdominal distention for the first time were found in both the AA and CO₂ groups, ruling out AA as the sole cause of these symptoms.Conclusion Abdominal post-DCBE discomfort seems to be less frequent than previously reported and is not effectively eliminated by CO₂. We still find the use of AA in DCBEs justified.     

Serum fluoride as an indicator of occupational hydrofluoric acid exposure

Summary To define the relationship between ionic fluoride concentration in the serum of workers and the amount of hydrofluoric acid (HF) in the work environment, pre-and postshift serum and urine samples of 142 HF workers and 270 unexposed workers were examined. The maximum and minimum concentrations of HF in the air in each workshop varied from the mean by less than 30%. The pre-exposure levels of serum and urinary fluoride in HF workers were higher (P < 0.001) than the control values. This suggests that fluoride excretion from the body continues for at least 12 h. The postshift serum and urinary fluoride concentrations of these workers were significantly higher (P < 0.001) than the preshift concentrations. A good correlation (r = 0.64) was obtained between postshift serum fluoride and postshift urine fluoride. There was a linear relationship between mean serum fluoride concentration and HF concentration in the workshop. A mean fluoride concentration of 82.3 g/l with a lower fiducial limit (95%, P = 0.05) of 57.9 g/l was estimated to correspond to an atmospheric HF concentration of 3 ppm. This is the maximum allowable environmental concentration recommended by the Japanese Association of Industrial Health, and it is also the threshold limit value suggested by the American Conference of Governmental Industrial Hygienists. The results demonstrate that exposure to HF can be monitored by determining the serum fluoride concentration.     

La respuesta sistémica Th17/IL-17A aparece antes del proceso neurodegenerativo en el hipocampo de ratas expuestas a bajas dosis de ozono

IntroductionExposure to low doses of O₃ leads to a state of oxidative stress. Some studies show that oxidative stress can modulate both the CNS and systemic inflammation, which are important factors in the development of Alzheimer disease (AD).ObjectiveThis study aims to evaluate changes in the frequency of Th17-like cells (CD3⁺CD4⁺IL-17A⁺), the concentration of IL-17A in peripheral blood, and hippocampal immunoreactivity to IL-17A in rats exposed to low doses of O₃.MethodsOne hundred eight male Wistar rats were randomly assigned to 6 groups (n = 18) receiving the following treatments: control (O₃ free) or O₃ exposure (0.25 ppm, 4 hours daily) over 7, 15, 30, 60, and 90 days. Twelve animals from each group were decapitated and a peripheral blood sample was taken to isolate plasma and mononuclear cells. Plasma IL-17A was quantified using LUMINEX, while Th17-like cells were counted using flow cytometry. The remaining 6 rats were deeply anaesthetised and underwent transcardial perfusion for immunohistological study of the hippocampus.ResultsResults show that exposure to O₃ over 7 days resulted in a significant increase in the frequency of Th17-like cells and levels of IL-17A in peripheral blood. However, levels of Th17/IL-17A in peripheral blood were lower at day 15 of exposure. We also observed increased IL-17A in the hippocampus beginning at 30 days of exposure.ConclusionThese results indicate that O₃ induces a short-term, systemic Th17-like/IL-17A effect and an increase of IL-17A in the hippocampal tissue during the chronic neurodegenerative process.