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71.
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J P Dilworth  R J White    E M Brown 《Thorax》1992,47(10):818-820
BACKGROUND: The presence of Haemophilus influenzae in the oropharynx is correlated with the subsequent development of chest infection. The importance of colonisation of the trachea by bacteria at the time of surgery is uncertain. This study investigated the tracheal flora at the time of intubation in 24 patients undergoing elective upper abdominal surgery. METHODS: The bacterial flora of the trachea was sampled in all 24 patients immediately after intubation and immediately before extubation. Patients were assessed postoperatively for the development of chest infection. RESULTS: Bacteria, including H influenzae in five cases, were isolated from the post-intubation brushings of the trachea of 15 patients. The pre-extubation brushings from only four patients yielded growth. Three of five patients developing a chest infection were colonised by H influenzae according to the postintubation brush, compared with two of 19 without chest infections. Before extubation two of five developing chest infections had H influenzae in the trachea but none of 19 without infection. All but one of the patients from whom H influenzae was isolated were smokers. CONCLUSIONS: These results suggest that the increased risk of postoperative chest infection in cigarette smokers may be due in part to colonisation of the trachea by H influenzae at the time of operation.  相似文献   
73.
We conducted a study of the 2 year cumulative incidence of trunkabnormalities in a cohort of 3,071 11 year old children (1,621boys, 1,450 girls). The following data were recorded: height,weight, signs of puberty and menarche. Trunk abnormality wasassessed in the erect child (asymmetry of shoulders and waistline,imbalance of the trunk, scoliosis, lordosis, kyphosis, swaybackand flexibility) and by the forward bending test (FBT) (ribhump or lumbar prominence, persisting scoliosis, kyphosis anddeviant lateral aspect). A normal FBT both at baseline and atfollow-up was found in 84% of the boys and in 79% of the girls.The 2 year cumulative incidence of an abnormal FBT was 10% inboys and 13% in girls.  相似文献   
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Exposure to inhalable wood dust and compliance with the British Control of Substances Hazardous to Health (COSHH) Regulations 1999 were assessed at a representative cross-section of the British woodworking industry. Median exposures ranged from 1.5 to 2.8 mg/m(3) across the selected industry groups, the lowest being in sawmilling and planing of wood. Overall, 27% of values exceeded the maximum exposure limit (MEL) at that time of 5 mg/m(3). These results showed that the percentage of exposures above the MEL was less than in a survey carried out 10 years earlier. A wide variation of exposures was identified at different machines and tasks. At least 90% at bandsawing and cross-cut sawing were <5 mg/m(3). In contrast, dust emission at circular sawing, sanding, cleaning and a miscellaneous group of activities was poorly controlled. Between 32 and 50% of results from these categories exceeded 5 mg/m(3). The lower exposures in sawmills were largely attributable to the low usage of sanders and a group of circular saws, to the high use of bandsaws and moulders and to coarser dust from undried timber. Compliance with the COSHH Regulations was inadequate. Companies that claimed to have some form of written COSHH assessment were generally no more effective at controlling exposure to dust than those without an assessment. Similarly the ability of premises that provided information, instruction and training on the risks to health from wood dust and on measures to prevent or control those risks was not generally greater than in those that did not. Maintenance of local exhaust ventilation systems emerged as essential for achieving good control. Companies that followed both the statutory 14-monthly thorough examination and testing schedule and a weekly check system were more successful in this respect than those that did not. In spite of this, local exhaust ventilation alone provided insufficient dust control at several woodworking activities.  相似文献   
76.
Rothner AD 《Headache》2003,43(4):427-428
Curr Pain Headache Rep. 2002;6:233-239.
This article reviews the less frequently encountered varieties of migraine. It is suggested that these disorders be approached by evaluating possible underlying etiologies before positively diagnosing migraine. This decreases the likelihood of "missing" structural or metabolic disorders. The classification, diagnostic evaluation, differential diagnosis, and treatment options of these disorders is reviewed and a selection of references appended for additional information.
Comment: Dr. Rothner is one of the most prominent pediatric neurology headache specialists in the country, and he sees a variety of atypical presentations of migraine. This is an excellent review of such presentations. SJT  相似文献   
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Kupfer  GM; D'Andrea  AD 《Blood》1996,88(3):1019-1025
Fanconi anemia (FA) is an autosomal recessive disease marked by developmental defects, bone marrow failure, and cancer susceptibility. FA cells are hypersensitive to DNA cross-linking and alkylating agents and accumulate in the G2 phase of the cell cycle in response to these agents. FA cells also display genomic instability, suggesting a possible defect in the p53 pathway. To test the effect of heterologous expression of FAC cDNA on drug-induced cytotoxicity, G2 accumulation, and p53 induction in FA cells, we compared two isogenic FA cell lines: HSC536N (mock), a FA type C cell line sensitive to mitomycin C (MMC), and the same cell line transfected (corrected) with wild-type FAC cDNA (HSC536N [+FAC]). HSC536N (+FAC) cells showed a 30-fold increase in resistance to MMC concentration. Similarly, increases in resistance were observed following exposure to cisplatin, carboplatin, and cyclophosphamide. In addition, HSC536N (+FAC) cells showed a twofold lower G2 accumulation following MMC treatment. To analyze the possible interaction of FAC with the p53 pathway, we analyzed p53 induction in mock and corrected cell lines following exposure to MMC. HSC536N (mock) cells induced p53 at lower MMC concentrations than HSC536N (corrected). Caffeine, a known G2 checkpoint inhibitor, not only inhibited G2 accumulation seen in both cell lines but also caused the resistant HSC536N (+FAC) to become as sensitive to MMC as HSC536N (mock) cell line. We conclude that the FAC protein has a specific cytoprotective effect and may function as a cell cycle regulator of the G2 phase of the cell cycle.  相似文献   
80.
Ho  AD; Maruyama  M; Maghazachi  A; Mason  JR; Gluck  S; Corringham  RE 《Blood》1994,84(10):3550-3557
Mononuclear cell preparations from peripheral blood after mobilization with hematopoietic growth factors have been shown to induce accelerated neutrophil and platelet recovery as compared with that induced by autologous bone marrow transplantation after myeloablative chemotherapy. Because these mononuclear cell products contain many immunocompetent cells other than hematopoietic progenitors, these accessory cells might contribute to the rapid immunohematopoietic reconstitution. We have monitored the concentrations of soluble CD4 (sCD4), sCD8, and sCD25; the recovery of the lymphocyte subsets and of natural killer (NK) cells; and the endogenous levels of granulocyte colony-stimulating factor (G-CSF), interleukin-3 (IL-3), IL-6, and granulocyte-macrophage-CSF (GM-CSF) in 12 patients who underwent high- dose chemotherapy supported by blood stem cells that were obtained by mobilization with chemotherapy and GM-CSF. The concentrations of both G- CSF and IL-6 peaked at 7 days after reinfusion of stem cells, and this transient elevation preceded the increase in the white blood cell count by approximately 5 to 7 days. The levels of sCD4 and sCD8 increased to a maximum on day 21, and the time to peak levels coincided with the maximum increase in white blood cell count, absolute neutrophil count, or lymphocytes. The levels of sCD25 were found to be elevated from day 7 to day 21. Statistically, the increases in sCD4, sCD8, sCD25, G-CSF, and IL-6 were highly significant, whereas there were no significant changes in IL-3 and GM-CSF. A rapid recovery of the NK activity was found in all 8 of the patients who could be monitored for this assay. Therefore, our study suggests that recovery of CD4+ cells, CD8+ cells, and NK activity coincided with that of neutrophils, which is preceded by a marked, but transient, elevation of IL-6 and G-CSF.  相似文献   
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