Increased procollagenase activating angiogenic factor in the vitreous humour of oxygen treated kittens.

Previous studies have demonstrated an increase in a low molecular weight angiogenic factor (ESAF) present in the retinae of kittens with oxygen induced retinopathy. The present paper describes differences in the quantity of ESAF extracted from the vitreous humour of control and oxygen treated animals and proposes a mechanism for the induction of intravitreal neovascularisation.     

Radiotherapy of periocular basal cell carcinomas: recurrence rates and treatment with special attention to the medical canthus.

Basal cell carcinomas of the eyelids, especially those in the medial canthal area, may cause extensive local destruction. Recurrent tumours are more aggressive and become progressively more difficult to treat; this is especially true for postirradiated recurrent, medial canthal, basal cell carcinomas. Tumours in this area should thus be treated by a technique which allows tissue sampling in order to gauge the adequacy of the treatment, with the goal being complete extirpation of the tumour. Excision monitored by frozen section control or Mohs' surgery is our recommendation based on a retrospective analyses of 631 eyelid basal cell carcinomas, half of which were primary tumours and half recurrent.     

Cavernous haemangioma presenting as an orbital mass after enucleation for a choroidal melanoma: case report.

A patient presented with an ipsilateral orbital mass four years after enucleation for a choroidal malignant melanoma. Clinical examination revealed a darkly coloured mass suggestive of recurrent melanoma. CT scanning indicated a locally extensive tumour. Management was by excision without resort to orbital exenteration. Pathological examination revealed a cavernous haemangioma. The natural history of this tumour is discussed.     

Stereoscopic evoked responses to crossed and uncrossed disparity accompanying simulated refractive error.

Evoked potentials were recorded to the occurrence of a disparate stimulus in dynamic random dot stereograms. Seven adult males, all of whom had vision which was normal or corrected to normal, participated in the experiment. Subjects viewed 100 ms duration stimuli which embodied 30 arc min of either crossed or uncrossed disparity under four conditions of spherical overcorrection: -0.25, +1.0, +2.0, +3.0 dioptres. The first condition, essentially normal refraction, yielded reliable behavioural reports of the stimulus and clear evoked potentials to both crossed and uncrossed disparity. With increasing overcorrection the behavioural reports became less reliable, and the evoked potentials were degraded for both conditions of disparity. The responses to the crossed disparity condition, however, showed significantly less degradation in both behavioural and electrophysiological measures. The implications of this finding may be that there are separate cortical subsystems for the processing of crossed and uncrossed disparity and that the former is more robust under non-ideal viewing conditions.     

2,5-Hexanedione excretion after occupational exposure to n-hexane.

The urinary excretion of the n-hexane metabolite 2,5-hexanedione (HD) was determined in four shoe factory workers during four workingdays that were preceded by four free days and followed by two free days. The correlation between excretion of HD and the n-hexane concentrations in the workroom air was evaluated. The air concentrations of n-hexane and those of acetone, toluene, and other organic solvents were monitored with charcoal tubes. All the urine from each worker was collected at freely chosen intervals during the experimental period and the following two free days. The samples were analysed by gas chromatography. The relative excretion of HD increased as the exposure to n-hexane increased, although it seemed that HD accumulated progressively in the body at the highest n-hexane concentrations and at higher total solvent concentrations.     

Back pain, back abnormalities, and competing medical, psychological, and social factors as predictors of sick leave, early retirement, unemployment, labour turnover and mortality: a 22 year follow up of male employees in a Swedish pulp and paper company.

A total of 391 male employees in a Swedish pulp and paper company were followed up for 22 years. As a part of a health examination in 1961 back pain reported by the subjects and abnormalities of the back as judged by the physicians were investigated with respect to predictive power regarding sick leave, early retirement, unemployment, labour turnover, and mortality during the follow up period. Univariate analysis showed that abnormalities of the back were better than back pain for predicting early retirement. Neither back pain nor back abnormalities had any predictive power with respect to long term sick leave, labour turnover, or mortality. Multivariate analyses of 26 variables were performed. Both self assessment of general health and back abnormalities were predictive for early retirement with a diagnosis of back disorder on the retirement certificate but self assessed health was a stronger predictor. Age, smoking, and neuroticism were predictors regarding early retirement for all diagnoses. Education had a negative association; neuroticism did not predict early retirement with a diagnosis of back disorder.     

Detection of Bacteroides fragilis Enterotoxin Gene by PCR

Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases.     

3种氟喹诺酮类药物抗生素后效应的研究

应用AVANTAGF分析仪的光密度法测定了环丙沙星（CPLX）、氧氟沙星（OFLX）和氟罗沙星（FLRX）的抗生素后效应（PAE）．结果表明氟喹诺酮类抗菌药物对革兰氏阳性球菌和革兰氏阴性杆菌均产生明显的PAE．并随抗菌药物浓度的增大、对受试菌的PAE逐渐延长．呈现了明显的浓度依赖性；3种抗菌药物对铜绿假单胞菌的PAE都较长．MIC均较小．显示了良好的杀菌效果：氯罗沙星对除金葡球菌之外的受试菌的PAE均比其它2药较长．PAE的存在提示在临床设计给药方案时．可适当延长给药间期．减少给药次数与剂量．仍能维持抗菌效果。