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排序方式: 共有1218条查询结果,搜索用时 15 毫秒
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Sema Burgaz Aysel Bayhan Ali Esat Karakaya 《International archives of occupational and environmental health》1988,60(5):347-349
Summary The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators. 相似文献
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F. F. Isik T. O. McDonald M. Ferguson E. Yamanaka D. Gordon 《The American journal of pathology》1992,141(5):1139-1149
Transplant arteriosclerosis (TA) has emerged as an obstacle to the long-term survival of transplanted organs, especially cardiac transplants. The animal models that have been used to study TA have not been fully characterized with regard to features such as the time course of cell proliferation and the sequence of cell types arriving in the developing intimal lesion. We present a model of TA based on a transplanted segment of abdominal aorta that helps address these questions. Two strains of rats (PVG x DA) underwent orthotopic aortic transplantation without immunosuppression and were killed at 14, 20, 40, and 60 days after transplantation. The within-strain control group displayed minimal evidence of cellular rejection with minimal to absent intimal lesions. In contrast, the allograft group showed a linearly increasing intimal lesion, up through 60 days after transplantation. The mechanism of intimal thickening was by an increase in cell number at the earlier time points with the later deposition of extracellular matrix. The early intimal lesion consisted mostly of mononuclear inflammatory cells (45%) with gradually increasing presence of smooth muscle cells (SMC) in the intima between 20 and 60 days. Conversely, the media showed gradual infiltration by macrophage-type cells with virtual loss of all SMC from the media by 40 days. The proliferative index showed a peak of 6% and 8% at 20 days in both the intima and media, respectively, and was preceded by the presence of macrophages. In fact, most of the proliferating cells at the earlier time points were either monocytes/macrophages, or were immediately adjacent to monocyte-/macrophage-rich regions. This straight artery segment model of transplant arteriosclerosis provides an easily quantifiable system in which the effects of different interventions (e.g., immunosuppressive regimens) can be tested. 相似文献
4.
Tasdemir Murat; Tasdemir Isik; Kodama Hideya; Tanaka Toshinobu 《Human reproduction (Oxford, England)》1993,8(12):2102-2107
To evaluate the possible effect of pentoxifylline on the acrosomereaction (AR) and its correlation with in-vitro fertilization(IVF), sperm samples obtained from 51 patients who underwentIVF treatment were studied. Acrosome reactions were evaluatedas spontaneous, pentoxifylline-treated and calcium ionophore(A23187) induced, before and after treatment. The correlationof AR with fertilization in vitro in spermatozoa pre-treatedwith pentoxifylline was sought. In cases with failure or verylow fertilization rate (10%) in their previous trials, spermatozoaafter swim-up were treated before insemination. Spontaneousacrosome loss remained low even after treatment (mean ±SD: 8.18 ± 1.74%). Response to A23187 was enhanced significantly(P < 0.001) by pre-treatment with pentoxifylline in 33 controlcases (group A) in which fertilization in vitro was previouslysuccessful without this treatment. Patients with at least twoepisodes of failed fertilization were divided into two groups.In 11 cases (group B), the IVF rate was improved significantly(P < 0.001) by the treatment. This was not observed in sevencases (group C) in which the treatment induced no increase inIVF rate. We achieved nine (27.3%) pregnancies in group A andfive (45.4%) pregnancies in group B. This study demonstratedthat pentoxifylline enhanced A23187 induced the acrosome reactionand this effect was correlated with improvement in IVF rate. 相似文献
5.
Umut Payza Ahmet Kayali Serkan Bilgin Zeynep Karakaya Fatih Esad Topal 《Asian journal of surgery / Asian Surgical Association》2021,44(6):854-859
Background/Objective: Ischemia is a leading cause of morbidity in Mechanical Intestinal Obstruction (MIO) in which the timing of decisions of whether to proceed to surgical or conservative treatment is critical in emergency departments (ED). While advanced technological options are available, patients may be negatively affected by the application of contrast agents or radiation. The use of ultrasound is limited because of the air in the intestines does not allow a good field of vision. While biomarkers can be considered as a good alternative option at this point. In the present study we examine the effect of hemogram and blood gas parameters on early surgical decision-making in MIO patients.MethodInvolved in this observational prospective study were 264 patients diagnosed with MIO who presented to the Department of Emergency Medicine, Ataturk Research and Training Hospital, Katip Celebi University between February 2018 and February 2019. Contrast-enhanced tomography (CECT) and laboratory results of the patients were recorded. Pathology reports of the patients who underwent surgery were collected. Laboratory data were analyzed by comparing CECT and pathology reports.ResultsIn a ROC analysis of the laboratory values of the patients who were diagnosed with ileus, the sensitivity was calculated as 80% and the specificity was 57.7 in values above WBC>10.75 (109/L), 96.6%, and the specificity was 31.1% in N/L > 2.9. For intestinal ischemia, the cut-off values were WBC> 12.6 and N/L > 3.2, Lactate >2.8 mmol/L and B.E < -3.6 mmol/L.ConclusionDiagnoses of ileus are based on the results examinations and imaging methods. More data are needed to support decisions on the timing of surgery in ED. WBC, N/L, Lactate and Base Excess indicate an ischemic segment. When the parameters are evaluated together, they strongly support early surgical decision-making regarding the treatment of intestinal ischemia. 相似文献
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Güler Kanra Pinar Isik Ates Kara Ali Bülent Cengiz Gülten Seçmeer Mehmet Ceyhan 《Pediatrics international》2004,46(6):663-668
BACKGROUND: Mumps vaccine has not yet been included in the routine vaccination programme, for this reason mumps is still one of the most common infections for children in Turkey. One of the major complication of mumps is meningoencephalitis, which although usually heals spontaneously, it may cause neurologic complications. METHODS: This study was undertaken to investigate epidemiologic and demographic characteristics in children with mumps and mumps meningoencephalitis and clinical/laboratory findings in children with mumps meningoencephalitis diagnosed over a 11 year period. A total of 2422 mumps and 135 mumps meningoencephalitis cases were covered in this study which constitutes one of the largest series of mumps meningoencephalitis in the literature. The mean age of mumps and mumps meningoencephalitis cases were 6.6 +/- 2.7 and 7.6 +/- 2.6 years, respectively. RESULTS: There was a male predominance both among the cases of mumps and mumps meningoencephalitis. The age and seasonal distributions were similar in the mumps and mumps meningoencephalitis groups. The most common symptoms of mumps meningoencephalitis were fever (97%), vomiting (94%) and headache (88.8%). The mean cerebrospinal fluid (CSF) total cell count and lymphocyte count were 540 +/- 460/mm(3) and 300 +/- 330/mm(3), respectively. The mean CSF protein and glucose levels were found to be 56.97 +/- 27.94 mg/dL and 53.67 +/- 15.46 mg/dL, respectively. The mean of CSF/blood glucose ratio was 0.53 +/- 0.16. The mean duration of hospitalization in mumps meningoencephalitis cases was found to be 5.1 +/- 2.4 days and this was longer in boys (P < 0.05). CONCLUSION: In patients with mumps meningoencephalitis, higher CSF protein levels and lower CSF glucose/blood glucose ratio were associated with longer hospitalization periods. There was no death. 相似文献
10.
Ayse Rodopman Arman Pinar Ay Nese Perdahli Fis Refika Ersu Ahmet Topuzoglu Ugur Isik Meral Berkem 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(3):420-424
Aim: In this population‐based study, we aimed to determine the total sleep duration (TSD), its association with socio‐economic status (SES) and behavioural symptoms among schoolchildren. Methods: A cross‐sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale. Results: The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms. Conclusion: Decreased total sleep duration is more prominent in boys, older children and children among higher socio‐economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio‐economic status might have a negative effect on both sleep hygiene and psychological well‐being in schoolchildren. 相似文献