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91.
Eyes with scleral rupture after blunt trauma are often complicated by proliferative vitreoretinopathy. A 56-year-old man sustained blunt trauma to his left eye. Visual acuity was light perception. The fundus was obscured by hyphema. Computed tomography imaging and the presence of extensive subconjunctival hemorrhage suggested scleral rupture. Prompt primary surgery to repair a 25-mm scleral rupture was performed under general anesthesia. No retinal detachment developed. Two years postoperatively, visual acuity increased to 12/20. This case shows that retinal detachment and proliferative vitreoretinopathy may not complicate extensive scleral ruptures under certain circumstances.  相似文献   
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93.
It is generally accepted that abnormal autonomic responsiveness may contribute to the pathogenesis of hyperesthetic rhinitis. Histologically, in the nasal mucosa, cholinergic fibers are found close to blood vessels, but are particularly numerous around the glands. Adrenergic fibers are found mainly around the vascular structures. Physiological and pharmacological studies demonstrate that parasympathetic hypersensitivity causes hypersecretion, and sympathetic hyposensitivity causes vasodilatation. alpha 1-adrenergic receptor function is dominant for this vasodilatation. Using radioligand binding techniques, it has been found that there is an increased number of muscarinic cholinergic receptors and a decreased number of alpha 1- and beta-adrenergic receptors in patients with nasal allergy, while the binding affinities do not change. In this report, using radioligand binding techniques, we investigated the relationships between the number of receptors and the degree of the hyperreactive nasal symptoms in patients with hyperesthetic rhinitis. The results are as follows. 1. The number of muscarinic cholinergic receptors of human nasal mucosa in patients with hyperesthetic rhinitis was related significantly (P less than 0.01) to the degree of hypersecretion induced by methacholine and frequency of blowing nose estimated from allergy diary. 2. There was no relationship between frequency of sneezing and the number of muscarinic cholinergic receptors. 3. The number of alpha 1-adrenergic receptors was related significantly (P less than 0.05) to the degree of swelling of nasal mucosa induced by methoxyamine. Judging from these results, it was assumed that pathogenesis of hyperreactive nasal symptoms may be associated at least partially to the changes of number of autonomic nerve receptors in the nasal mucosa.  相似文献   
94.
BACKGROUND: The spread of human immunodeficiency virus (HIV) in Cambodia is mainly caused by sexual transmission and the high-risk group in this country are female commercial sex workers (CSW). There are two types of CSW, direct CSW (DCSW) and indirect CSW (IDCSW), who are different from each other in sexual activities. This study was conducted in order to describe the risk factors on HIV for each type of CSW, and to establish effective preventive strategies against the HIV epidemic among CSW. METHODS: The participants, 143 DCSW and 94 IDCSW, were interviewed using a questionnaire to determine their demographic characteristics and behaviour. Blood samples were taken for serological tests on HIV, Chlamydia trachomatis and syphilis. The association between their behavioural pattern and their serological results was analysed. RESULTS: The questionnaire study showed that IDCSW had a riskier behavioural pattern than DCSW. The HIV seroprevalence rates of the DCSW and the IDCSW were 52.4% and 22.3%, respectively. Univariate logistic analyses showed a significant association between HIV antibody (HIV-Ab) and current age, age at commencement of commercial sex work, duration of commercial sex work, and the seropositivity of Chlamydia trachomatis-IgG antibody (CT-IgG-Ab) among the DCSW. The analyses also showed a significant relationship between HIV-Ab and CT-IgG-Ab among the IDCSW. CONCLUSIONS: Improving condom use rate is very important in order to prevent an HIV epidemic among the two types of CSW. This study also suggests it is important to prevent sexually transmitted disease (STD) such as Chlamydia trachomatis infection. The STD control programme could be efficient for HIV prevention, especially among DCSW.  相似文献   
95.
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97.
Inhalation toxicokinetics of p-dichlorobenzene ( p-DCB) in humans was evaluated, and the amounts of daily absorption and internal accumulation were estimated in order to obtain fundamental data for the risk assessment of chronic low-level exposure in the general population. Seven male subjects continuously inhaled about 2.5 ppm of p-DCB vapor for 1 h, and the concentration-time courses of p-DCB in their exhaled air and serum and of urinary 2,5-dichlorophenol (2,5-DCP), a major metabolite of p-DCB, were examined. The toxicokinetics of p-DCB was evaluated on the basis of the time courses using a linear two-compartment model. The amounts of p-DCB absorbed daily and the internal accumulation in chronic low-level exposure were extrapolated using the estimated toxicokinetic parameters. p-DCB was transferred from inhaled air to the body with a constant high absorption rate during exposure. The major route for elimination from the body was urinary excretion followed by metabolism, not exhalation. However, during 9-11 h after the start of exposure, the fraction of p-DCB excreted in urine was only 5-16% of the amount absorbed. Furthermore, most of the absorbed p-DCB seemed to be distributed rapidly to the tissues, such as fat, according to toxicokinetic analysis. Consequently, p-DCB seems to require a long time to be completely eliminated from the body. The amounts of daily absorption and internal accumulation were extrapolated to average 0.27 mg/day and 2.9 mg, respectively, in the subjects exposed chronically to 1 ppb of p-DCB. The amount absorbed daily agreed approximately with that extrapolated from rats which inhaled p-DCB in our previous study.  相似文献   
98.
The incidence of peripheral pulmonary adenocarcinoma has increased in recent years. Clara cell has been known as target for carcinogens and source of pulmonary tumors. One of the presumed roles of the bronchiolar Clara cell is the secretion of pulmonary surfactant into the bronchiolar lumen. To establish the secretory morphology of Clara cell, a well-defined secretory agonist, isoproterenol (500 mg/kg) and the antagonist, propranolol (20 mg/kg), were administered into five-week old mice. The secretory response was examined at 1 hour and 4 hours after injection. Ultrastructural morphometry was used to quantitate the secretory response by measuring area of apical cap of the Clara cells. Isoproterenol caused a significant increase in area of apical cap of Clara cells 1 and 4 hours after injection (p < 0.0001), while pretreatment with propranolol prevented this effect at 4 hours. Propranolol alone significantly decreased the area of Clara cells (p < 0.0001). Clara cells secretory granules disappeared 1 hour after propranolol plus isoproterenol administration, and the granules reappeared at 4 hours. The accelerated secretion of Clara cells by isoproterenol provides evidence of their secretory mechanism controlled by beta-adrenergic agonists. The study has confirmed the secretory role of Clara cells. The secretion is both apocrine and merocrine type.  相似文献   
99.
In the present study we examined the combined effect of application of a capacitively coupled electric field (CCEF) and the tissue respiration stimulating agent, Solcoseryl, on the promotion of bone formation around dental implants histologically and mechanically. After a dental implant was inserted into each femur of Japanese white rabbits, Solcoseryl (2 ml/kg) was administered intravenously in the ear vein and a CCEF was applied for 4 h per day for 14 days. The degree of bone formation on microscopic observation, bone contact ratio, bone surface area ratio, and the level of removal torque of the implant in the Solcoseryl- and CCEF-treated group were significantly higher than the respective value in the control group, which had not been treated with Solcoseryl nor CCEF. Thus, the combination of CCEF stimulation and Solcoseryl effectively promoted the formation of new bone. It is suggested that the clinical use of a combination of CCEF stimulation and Solcoseryl for dental implants promotes osseointegration.  相似文献   
100.
A 57-year-old man with renal cell carcinoma associated with membranous glomerulonephropathy (MGN) developed a transient amelioration of the nephrotic syndrome after excision of the tumor. We tried to identify a nephritogenic tumor antigen using the immunoblotting technique in this patient with MGN, since previous studies examined the interaction between tumor antigens and IgG eluted from the kidney tissue using immunofluorescence or immunodiffusion techniques, and no studies have identified the specific tumor antigen with the immunoblotting method. In the present study, no significant immunoreactivity was noted between the IgG eluted from renal cortical tissues of the patient and renal cell carcinoma proteins. Further studies are necessary to establish the pathogenic mechanism of MGN associated with malignancy.  相似文献   
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