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71.
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   
72.

Introduction  

The purpose of the present study was to investigate the use of an operative technique incorporating the LigaSure vessel sealing system in patients undergoing type 7 total laparoscopic hysterectomy (TLH) and adnexectomy with or without Burch colposuspension.  相似文献   
73.

Purpose  

To investigate the outcomes of singleton and twin pregnancies that were complicated by spontaneous preterm labor and received nifedipine tocolysis.  相似文献   
74.
BACKGROUND: TTV DNA has been reported in patients with a broad spectrum of hepatic disorders as well as in healthy people. AIM: To clarify the role of TTV in children with liver disease and in healthy children. METHODS: Degenerate primers designed to amplify a target sequence from the ORF 1 region of TTV genome were used for nested PCR, to detect TTV DNA in sera. RESULTS: TTV was detected in 3 of 18 children with chronic hepatitis B (16.7%), 2 of 17 hepatitis B carriers (11.8%), 2 of 17 children with cryptogenic chronic liver disease (11.8%), and 1 of 40 (2.5%) children without liver disease. The infection rate was similar among the various study groups and in the various age groups. There was no difference between TTV positive and negative children in respect to gender, history of surgery, parenteral treatment, transfusion of blood and blood products, presence of hepatomegaly, splenomegaly, jaundice, and transaminase values. CONCLUSION: TTV does not seem to have an etiologic role in cryptogenic liver disease in children and does not seem to influence the clinical course of liver disease.  相似文献   
75.
Hepatocellular carcinoma (HCC) metastasis to the lymph nodes has been reported in about one-third of autopsies, mostly to the regional chains. Involvement of cervical lymph nodes is extremely rare. We encountered an unusual case of HCC in a patient with chronic liver disease presenting with right-sided anterior cervical lymph node metastasis skipping mediastinal and supraclavicular chains. One should be aware of that unusual site of presentation and metastasis of HCC so as not to miss the diagnosis.  相似文献   
76.
Periodontal ligament cells play a crucial role in the regeneration of periodontal tissues and an undifferentiated mesenchymal cell subset is thought to exist within this population. The aim of this study was to assess the osteogenic differentiation potential of human periodontal ligament fibroblasts (hPDLFs) in three dimensional (3D)-osteogenic culture environment following encapsulation in chitosan-hydroxyapatite (C/HA) microspheres with the size range of 350-450 microm. Human PDLF cultures were established and three experimental groups were formed: (i) two-dimensional (2D)-culture as single cell monolayer, (ii) 3D-static culture of C/HA encapsulated hPDLFs, and (iii) 3D-dynamic culture of C/HA encapsulated hPDLFs in a rotating wall vessel bioreactor. The cells were cultured in standard culture medium supplemented with beta-glycerophosphate, dexamethasone, and ascorbic acid. After 21 days, immunohistochemistry was performed using antibodies against osteonectin, osteopontin, bone-sialoprotein, and osteocalcin as osteogenic differentiation markers. Phase-contrast and scanning electron microscopy observations were used for histological and morphological evaluation. The combined effects of osteoinductive medium and HA-containing composite microsphere material on encapsulated hPDLFs resulted in the transformation of a considerable portion of the cells into osteoblastic lineage at the end of the experiments. Results demonstrate the ability of hPDLFs to undergo osteogenic differentiation upon induction in vitro, both under 2D and 3D culture conditions. C/HA microspheres in microgravity bioreactor may serve as a suitable 3D environment to support the osteogenic differentiation of human PDLFs, in vitro.  相似文献   
77.
Identification and evaluation of pain in critical care patients may be difficult because of communication problems. Moreover, at present there are very few nursing studies that examine the attitudes of critical care nurses towards the assessment of patients' pain. This study was designed to determine the approach of critical care nurses towards assessing patients' pain levels, and to evaluate the problems in nursing diagnosis of those having difficulty in articulating their pain symptoms. We used a questionnaire to assess nurses attitudes to patients' pain. The study sample consisted of 91 critical care nurses who were recruited between January and February 2002. The results suggest that patient pain was considered undesirable by 44% of nurses. About 70-3% of the nurses reported resorting to administering analgesics to relieve their patients' pain. Some 57.1 % of nurses stated that they would have investigated whether the patients had really been experiencing pain, prior to administering the prescribed analgesics to patients. Some 85.7% of the sample indicated that the patients themselves would make the most accurate evaluation of their pain. The data suggested that 39.6% of nurses did not know how to evaluate pain symptoms in critical care patients suffering from complicated problems, and that 37.4% evaluated pain by monitoring the patients' behaviours. The study demonstrated that most of the critical care nurses did not know how to evaluate pain in patients having communication problems. The paper concludes by suggesting that there is a clear need to address nursing education and training with regard to evaluation and management of patients' pain whilst in critical care environment.  相似文献   
78.

Objective:

The hypothalamus plays a crucial role in the regulation of feeding behavior. The anorexigenic neuropeptide alpha-melanocyte-stimulating hormone (α-MSH) and the orexigenic neuropeptide agouti-related protein (AgRP) are among the major peptides produced in the hypothalamus. This study investigated the plasma concentrations of α-MSH and AgRP in underweight and obese children and their healthy peers. The associations between α-MSH and AgRP levels and anthropometric and nutritional markers of malnutrition and obesity were also assessed.

Methods:

Healthy sex-matched subjects aged 2 to 12 years were divided into 3 groups, as underweight (n=57), obese (n=61), and of normal weight (n=57). Plasma fasting concentrations of α-MSH and AgRP were measured by enzyme-linked immunosorbent assay. The differences between the three groups as to the relationships between plasma concentrations of α-MSH and AgRP and anthropometric data, serum biochemical parameters and homeostatic model assessment of insulin resistance were evaluated.

Results:

Obese children had significantly lower α-MSH levels than underweight (1194±865 vs. 1904±1312 ng/mL, p=0.006) and normal weight (1194±865 vs. 1762±1463 ng/mL, p=0.036) children; there were no significant differences in the α-MSH levels between the underweight and normal weight children (p=0.811). Also, no significant differences were observed between the underweight and obese children regarding the AgRP levels (742±352 vs. 828±417 ng/mL, p=0.125). We found a significant positive correlation between plasma α-MSH and AgRP levels across the entire sample.

Conclusion:

This study is the first to demonstrate body weight-related differences in α-MSH and AgRP levels in children. Circulating plasma α-MSH levels in obese children were markedly lower than those of underweight and normal-weight children. This suggests that α-MSH could play a role in appetite regulation.  相似文献   
79.
Changes in vascular endothelial growth factor (VEGF), angiotensin-converting enzyme (ACE), matrix metalloproteinase (MMP)-9, and endothelial nitric oxide synthase (eNOS) mRNA expression profiles and oxidative stress in the eye tissue microenviroment may have important roles in ocular neovascularization and permeability in proliferative diabetic retinopathy. The present study investigated the effects of resveratrol (RSV) treatment on the mRNA expression profile of VEGF, ACE, MMP-9, and eNOS, which are associated with vascular neovascularization, and glutathione, protein carbonyl, and nitrite-nitrate levels, which are markers of oxidative stress in eyes of diabetic rats. Twenty-four Wistar albino male rats were divided into four groups. After diabetes induction with streptozotocin (10?mg/kg/day) RSV was administered to the RSV and diabetes mellitus (DM)?+?RSV groups for 4 weeks. The mRNA levels were measured by quantitative real-time polymerase chain reaction assay, and biochemical estimations were determined with spectrophotometric assays in eye homogenates. The mRNA expression levels of VEGF, ACE, and MMP-9 were increased in the DM group compared with the control group, and RSV treatment decreased their mRNA levels. Expression of eNOS mRNA was increased in the RSV and DM groups and decreased in the DM?+?RSV group. Nitrite-nitrate levels and protein carbonyl content were increased and glutathione levels were decreased in the DM group compared with controls. Consequently, these data suggest that RSV suppressed the expression of eNOS, which is actively involved in the inflammation and healing process in chronic diabetes. Although oxidative stress was increased in eye tissue from diabetic rats, mRNA levels of VEGF, MMP-9, and ACE genes associated with vascular remodeling did not change in diabetic eyes.  相似文献   
80.
Background/aims: Inappropriate down regulation of an activated immune system is considered as the main pathogenetic mechanism in inflammatory bowel disease. Migration of circulating cells to a diseased intestine is considered as an important factor in the pathogenesis of inflammatory bowel disease. We aimed to evaluate some features of circulating immune cells in inflammatory bowel disease. Methods: Twenty-two control, 29 Crohn's disease and 17 ulcerative colitis patients were studied. CD2, CD3, CD4, CD8, CD11b, CD11c, CD25, CD45RA, CD45RO, CD54 and HLA DR on the surface of peripheral blood lymphocytes and CD11b, CD11c, CD45RA and CD45RO on the phagocytes were researched with two-color immunofluorescence flow cytometry. Results: The percentages of CD2+ and CD4+ lymphocytes were found significantly reduced in ulcerative colitis. CD3+ and CD8+ lymphocytes in inflammatory bowel disease were higher than in controls. CD45RA+ lymphocytes were found significantly decreased in ulcerative colitis and active Crohn's disease. CD45RO+ lymphocytes and CD45RO+, CD11b+ and CD11c+ phagocytes were significantly increased in Crohn's disease. Conclusions: We demonstrated that there were significant differences between ulcerative colitis and Crohn's disease in the expression of some important surface markers on the peripheral blood immune cells. It seems that circulating CD11b-CD11c and CD45RA-CD45RO expressing phagocytes are important in inflammatory bowel disease and may be useful in distinguishing Crohn's disease from ulcerative colitis. These findings may give us some clues about the immunopathogenesis of inflammatory bowel disease.  相似文献   
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