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991.
Exposure to lead has been shown to have a deleterious effect on the immune system. However, the findings of previous studies have been inconsistent. This may have been due to the increased susceptibility to intracellular pathogens and increased polyclonal and antigen-specific responses on exposure to lead. The objective of the current study was to evaluate the immune function of long-term workers with lead in a battery manufacturing plant. Junior high school teachers were used as a control group. Our results showed that the percentage of monocytes was significantly higher among lead workers than in the control group, but T8 cell levels were lower. The T4/T8 ratio was significantly higher among lead workers (1.42) than in the control group (1.18). After adjustment for age, gender and disease using multiple linear regression models, the percentage of B-cells and number of lymphocytes, monocytes and granulocytes were all significantly decreased among lead workers compared with the control group. Our findings showed that lead caused a marked immunotoxic and immunosuppressive effect among long-term lead workers. 相似文献
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Hsu JW Tsai PL Hsiao TH Chang HP Lin LM Liu KM Yu HS Ferguson D 《Australian dental journal》1999,44(1):40-45
Chinese populations differ from Caucasoids by having a high prevalence of shovel trait and a low prevalence of Carabelli's trait. This study was conducted to investigate the association between the shovel and the Carabelli's traits in a Chinese population. The research design investigated a Chinese population that resides in southern Taiwan. The ancestors of this Chinese population migrated to Taiwan from mainland China, mainly from Fukien and Kwangtung. The effects of sex and age on Carabelli's trait were controlled in this investigation, as was the association between tooth size and Carabelli's trait. Results show that males were more likely to have Carabelli's trait expressed on teeth than females. The buccolingual diameter of Carabelli's trait teeth was larger than that of teeth without the trait. After controlling for sex, age, and tooth size, the existence of the shovel trait increased the likelihood of having Carabelli's trait by a factor of five and a half, which is a significant effect. 相似文献
997.
We present a 9-year-old boy with central precocious puberty and hydrocephalus caused by a human chorionic gonadotropin (beta-hCG) secreting pineal tumor. High levels of beta-hCG in the serum and cerebrospinal fluid were observed in this patient. The patient received radiotherapy and chemotherapy without surgical intervention. Subsequently, significant tumor regression was observed and the serum beta-hCG level normalized. There was no evidence of tumor recurrence at follow-up one year after treatment. The role of tissue biopsy to establish a diagnosis in pineal germ cell tumors remains controversial because it can be a difficult procedure and may be dangerous, causing severe complications. In this patient, the elevated beta-hCG level indicated the presence of a tumor and was considered sufficient evidence to warrant initiating treatment. 相似文献
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PURPOSE: To report the therapeutic effect and complications of amniotic membrane transplantation (AMT) in acute fungal keratitis. METHODS: Diagnosis of fungal keratitis was confirmed by cultures in 23 eyes of 23 patients. The indications to perform AMT were to promote reepithelialization in non-healing ulcers or to prevent corneal perforation. Antifungal agents were administered throughout the whole course of hospitalization. Repeated cultures were performed immediately before AMT. The main outcome measurements were epithelial healing rate, necessity of therapeutic penetrating keratoplasty (TPK), and persistence of infection. RESULTS: During a mean follow-up time of 20.6 months +/- 23.22 (6-65 months) AMT was performed during the active phase of the keratitis (fungal culture was still positive) in 16 patients (69.6%), and during the inactive phase (fungal culture negative) in 7 patients (30.4%). Single-layer AMT was performed in 17 patients, and double-layer AMT was performed in 6 patients with corneal perforation and anterior chamber collapse. Complete epithelialization was observed in 12 patients (75%) in the active group and in 7 patients (100%) in the inactive group. Treatment failure requiring TPK was experienced in 4 patients (25%) in the active group. Persistent fungal keratitis was noted in 2 patients (8.7%) in that group. The final visual acuity improved in 17 cases, worsened in 2 cases, and remained unchanged in 4 cases. Twelve of the 23 eyes (52.2%) in this study preserved useful vision (20/400 and better) with or without subsequent surgeries. CONCLUSION: AMT is effective in promoting epithelialization and preventing corneal perforations in acute fungal keratitis, and there is no risk of rejection. However, the risk of persistent or recurrent infection necessitates continued antifungal treatment and patient monitoring. 相似文献
1000.
PURPOSE: To report a case of camphor-related self-inflicted keratoconjunctivitis secondary to delusions of parasitosis. METHODS: A 61-year-old man with delusions of parasitosis suffered from camphor-related self-inflicted ocular trauma that manifested with corneal epithelial defects and secondary anterior chamber reaction. Two episodes of exacerbation of the ocular conditions related to the use of camphor occurred. The left eye had secondary infection with Sternotrophomonas maltophilia and Staphylococcus aureus in the second episode of exacerbation. RESULTS: The right eye recovered well with the treatment of topical lubricants and corticosteroids and had best-corrected visual acuity (BCVA) of 20/25. The infection of the left eye led to corneal perforation, necessitating penetrating keratoplasty; BCVA was hand motions because of a mature cataract. Olanzapine therapy for 1 month to decrease the delusions of parasitosis and 24-hour watch to prevent the use of camphor led to the resolution of self-inflicted keratoconjunctivitis in the patient. CONCLUSIONS: Delusions of parasitosis may lead to vision-threatening self-inflicted ocular trauma. This may be the first case report of pure camphor-related self-inflicted toxic keratoconjunctivitis. 相似文献