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71.
BACKGROUND: The role of inflammation in the pathogenesis of cardiovascular disease is well established. C-reactive protein (CRP) is the strongest independent predictor of myocardial infarction and stroke in women. Recent studies have indicated that CRP levels are raised during use of combined oral contraceptives (COCs). OBJECTIVES: The aim of the study was to investigate the effect of COCs on serum CRP levels and to indicate the underlying mechanisms of an expected increase. METHOD: In a prospective randomized cross over-study 35 women used two different preparations of COC, one second and one third generation. Serum levels of CRP, serum amyloid A (SAA), interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), antibodies against oxidized LDL, insulin and insulin-like growth factor-I (IGF-I) along with insulin-like growth factor binding protein-1 (IGFBP-1) and IGFBP-3 were analyzed before and during the two treatments. E-selectin, von Willebrand factor and factor VIII concentrations in plasma were also measured. RESULTS: A rise in serum CRP was observed during both treatments; the median level increased from 0.45 mg L(-1) at baseline to 1.48 mg L(-1) with second generation and to 2.02 mg L(-1) with third generation COC. The serum levels of SAA increased slightly during treatment with the third generation COC. IL-6 and TNFalpha were unaffected by treatment. Both preparations lowered IGF-I and raised IGFBP-1 and IGFBP-3 concentrations. CONCLUSION: The raised serum CRP concentration during treatment with COCs appears to be related to a direct effect on hepatocyte CRP synthesis and does not reflect IL-6 mediated inflammation, endothelial activation or induction of insulin resistance.  相似文献   
72.
Intravaginal misoprostol has been shown to be effective forcervical priming before a surgically induced abortion. The objectivewas to investigate the effectiveness of oral misoprostol incervical dilatation prior to vacuum aspiration between the 6thand 12th weeks of pregnancy. The results showed that in nulliparouspatients, the median cervical dilatation in the treatment group(7.8 mm) was significantly greater than that in the placebogroup (3.7 mm). In multiparous patients, the difference wasalso statistically significant (9.8 versus 6.0 mm). The easeof dilatation, assessed subjectively by the operating surgeons,was significantly improved in the treatment group. There wasalso a significant reduction in the duration of the operationand in the mean blood loss in the treatment group. The side-effectsencountered in the treatment group were mild and well acceptedby the women. Oral misoprostol is an effective and safe methodfor cervical dilatation prior to vacuum aspiration in firsttrimester pregnancy.  相似文献   
73.
Summary The pharmacokinetics of single intravenous and oral doses of L-carnitine 2 g and 6 g has been investigated in 6 healthy subjects on a low carnitine diet.Carnitine was more rapidly eliminated from plasma after the higher dose. Comparing the 2-g and 6-g doses, the t1/2 of the elimination phase () was 6.5 h vs 3.9 h, the elimination constant was 0.40 vs 0.50 h–1 and the plasma carnitine clearance was 5.4 vs 6.11 × h–1 (p<0.025), thus showing dose-related elimination.Saturable kinetics was not found in the range of doses given. The apparent volumes of distribution after the two doses were not significantly different and they were of the same order as the total body water. Urinary recoveries after the 2-g and 6-g doses were 70% and 82% during the first 24 h, respectively.Following the two oral dosing, there was no significant difference in AUCs of plasma carnitine. Urinary recoveries were 8% and 4% for the 2-g and 6-g doses during the first 24 h. The oral bioavailability of the 2-g dose was 16% and of the 6 h dose 5%. The results suggest that the mucosal absorption of carnitine is already saturated at the 2-g dose.  相似文献   
74.
The purpose of this study was to describe the role played by the ability to estimate caries depth in successfully deciding to treat dentin caries when making use of bitewing radiographs as a diagnostic test. A 10% random sample (n = 444) of Dutch dental practitioners was sent a two-wave questionnaire concerning radiographic caries diagnosis and restorative treatment decision making. The second wave consisted of simulated bitewing radiographs of 105 tooth surfaces with and without dentin caries according to two measuring standards: (a) a micro-radiographic "gold" standard and (b) a norm of expert observers. The dentists were asked to diagnose caries at 4 depths of penetration using a 5-point certainty scoring system to measure diagnostic ability; and to make a treatment decision for each surface. The overall response was 61% (273). A regression analysis was carried out using the chance per dentist of correctly deciding to treat dentin caries as the dependent variable. The degree of agreement with the experts' diagnosis of radiographic caries depth was used to create variables measuring diagnostic ability. Five significant (P less than 0.05) variables explained 60% (R2 = 0.60) of the variation in decision making. The best diagnostic ability variable explained 47% of the variation while the treatment criterion reportedly used explained 3%. We conclude that the ability of practitioners to interpret radiographs plays a major role in treatment decision making and that their reported treatment decision making criteria should not be taken at face value.  相似文献   
75.
采用纱球进行口腔护理的效果观察   总被引:5,自引:0,他引:5  
龙羽玲 《医学信息》2005,18(10):1359-1360
目的探寻有效的口腔护理方法,取得更好的清洁口腔及洁牙效果。方法随机对53例有口腔护理适应症、意识清醒的患者,用纱球或棉球分别作左或右侧牙齿及口腔粘膜的清洁护理,并按同一标准进行效果评价。结果53例患者,以纱球擦洗侧,效果好的为42例,一般为11例,差为0例。以棉球擦洗侧,效果好为13例,效果一般为40例,差为0例,两组效果比较有显著性差异(P<0.01)。结论以纱球作口腔护理的清洁效果明显优于棉球的清洁效果。  相似文献   
76.
An immunization regimen has been developed which yields a high frequency of hybridomas producing IgA isotype, antigen-specific antibody when spleen cells from immunized mice are fused with non-immunoglobulin secreting murine myeloma cells. Germfree BALB/c mice were carrier-primed with sheep erythrocytes (SRBC) by gastric intubation (GI) for 2 consecutive days followed 1 week later by GI with trinitrophenyl (TNP)-haptenated SRBC. After 7 days, spleen cells were fused with non-immunoglobulin secreting myeloma cells (X63-Ag8.653), and 2–3 weeks later, culture wells were scored for hybrid clones. Of 240 culture wells plated, 157 wells (65.4%) exhibited clones producing anti-TNP antibodies as determined by enzyme-linked immunosorbent assay. A total of 50 specific cell lines were established, of which 27 clones (54%) produced IgA isotype anti-TNP antibodies, while the anti-TNP antibodies produced by the remaining 23 clones were approximately equally distributed between the IgM and IgG isotypes. The IgA and IgM monoclonal antibodies were more effective in hemagglutinating TNP-SRBC than were IgG isotype antibodies. This study describes a method for production of a high number of antigen-specific IgA hybridomas which will allow production of IgA monoclonal antibodies to important antigens on mucosally-associated pathogens, and thus allow elucidation of functions of IgA antibody at mucosal surfaces.  相似文献   
77.
Context: Athletes in the United States are at high risk for using spit (smokeless) tobacco (ST) and incurring its associated adverse health effects.Objective: To examine whether an athletic trainer-directed ST intervention could decrease initiation and promote cessation of ST use among male collegiate baseball athletes.Design: Stratified, cluster-randomized controlled trial.Setting: Fifty-two California colleges.Patients or Other Participant(s): A total of 883 subjects in 27 intervention colleges and 702 subjects in 25 control colleges participated, as did 48 certified athletic trainers.Intervention(s): For college athletic trainers and associated dental professionals, a 3-hour video conference, and for collegiate athletes, an oral cancer screening with feedback and brief counseling during the preseason health screenings, athletic trainer support for cessation, and a peer-led educational baseball team meeting.Main Outcome Measure(s): The subjects' ST use over 1 year was assessed by self-report. At the end of the study, the certified athletic trainers were mailed a survey assessing their tobacco use and perceptions and behavior related to tobacco control in the athletic environment. We used multivariable logistic regression models for clustered responses (generalized estimating equations) to test the difference between groups in ST-use initiation and cessation and to identify significant overall predictors of noninitiation and cessation of ST use.Results: Of the 1585 athletes recruited, 1248 (78.7%) were followed up at 12 months. In addition, 48 of the 52 athletic trainers (92%) responded to the 1-year follow-up survey. The ST-use initiation (incidence) was 5.1% in intervention colleges and 8.4% in control colleges (generalized estimating equation odds ratio = 0.58, 95% confidence interval = 0.35-0.99). Predictors of ST noninitiation were low lifetime tobacco and monthly alcohol use (odds ratio = 1.98, 95% confidence interval = 1.40- 2.82) and athletic trainers' report that the baseball coach supported ST-use prevention activities (odds ratio = 1.43, 95% confidence interval = 1.11-1.83). Although at 1 year, cessation of ST use was relatively high in both groups (36%), we noted no significant difference between the groups (odd ratio = 0.94, 95% confidence interval = 0.70-1.27).Conclusions: The intervention was significantly effective in preventing incident ST use but did not significantly increase cessation beyond that seen in the control group. The latter finding is inconsistent with previous studies and may be explained by spillover of the intervention to control colleges, other anti-tobacco activity in control colleges, and/or the small sample of dependent ST users enrolled in the study.  相似文献   
78.
Tumor metastases are extremely rare in striated muscles. This is surprising given the fact that this tissue constitutes 60% of body weight. The present study focuses on small molecules produced and secreted by muscle cells which possess anti-cancer activity in vivo. Recently we have shown that a low molecular weight fraction (<1000 Dalton) of skeletal muscle cell conditioned medium (muscle factor-MF), markedly inhibits the proliferation of carcinoma, sarcoma or melanoma cell lines in vitro. The MF exerts a cytostatic effect on tumor cell growth and arrests the cells in the G0/G1 of the cell cycle. However, normal cell proliferation, such as bone marrow and fibroblasts, was stimulated following incubation with MF. In this study, the effect of orally administered MF on melanoma and sarcoma growth was examined in mice. The administration of MF to mice inoculated intravenously with melanoma (B16–F10) or sarcoma (MCA-105) cells, resulted in a statistically significant inhibition of metastatic lung foci. In a different model, melanoma was induced in the foot pad and after development of a local lesion, the leg was amputated. A prolonged survival time was observed in the MF treated groups. Since the MF stimulated bone marrow cell proliferation in vitro, we decided to test its efficacy as an inhibitor of the myelotoxic effect exerted by chemotherapy, in vivo. MF, administered after chemotherapy, restored the number of white blood cells and yielded an increased percentage of neutrophils compared with the decline in these parameters after administration of chemotherapy alone. Thus, it is indicated that MF exerted a systemic anti tumor and chemoprotective effect when given orally. It can be concluded that it is bioavailable and is not biodegradable in the digestive system. MF may be considered as a potential therapy for the prevention of tumor spread. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
79.
Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed.  相似文献   
80.
BACKGROUND: We investigated the hypothesis that long-term use of oral contraceptives (OCs), in particular high-dose OCs, could postpone age at menopause. METHODS: Data was used from 8701 women who participated in a breast cancer screening programme in Utrecht (DOM-3 cohort), and who did not use hormone replacement therapy (HRT) or OCs in the 4 years prior to their last menses. Data on OC-use, menopausal status, age at menopause, year of birth, parity, smoking behaviour, socio-economic status, body mass index and age at menarche was available. Use of high-dose OCs has been defined in this study as OC-use before 1972. The data was analysed by means of linear regression and Cox's proportional hazards analysis. Women still menstruating, women with surgical menopause and women lost to follow-up were censored at their last known date of menstruation. Endpoint was the natural menopause (n = 4589). RESULTS: The use of high-dose OCs advanced the onset of menopause by approximately 1.2 months for every year of OC-use compared with no OC-use. High-dose OC-use for > or = 3 years, adjusted for confounding variables, increased the risk of earlier menopause compared with no OC-use (adjusted hazard ratio 1.12; 95% CI 1.03--1.21). The use of lower dose OCs did not increase the risk of earlier menopause (adjusted hazard ratio 1.00; 95% CI 0.91--1.09). CONCLUSIONS: These results are inconsistent with the hypothesis that long-term use of OCs could postpone the onset of menopause by inhibiting follicle depletion. Possible explanations are discussed.  相似文献   
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