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31.
32.
Discolored and normal areas in the enamel of eleven primary teeth from children born to diabetic mothers were analysed with ion probe technique. These teeth were compared with four teeth from children born to healthy mothers. Fourteen different mass numbers were recorded. The affected areas showed a proportionally higher content of organic material, but the differences in recorded values reached statistical significance only in the postnatal enamel. The study revealed a considerable biological variation in the chemical composition of deciduous tooth enamel. The brown areas may be partly related to variation in physical properties.  相似文献   
33.
The aim of this study was to in vitro evaluate the micro leakage of a fissure sealant on sound and demineralized enamel using thermo cycling. The effect of the sealing procedure on sound and demineralized enamel were assessed on human premolars that were divided into one Control group and two Test groups. The Control group served as a baseline reference for the subsequent test procedures. The crowns of five teeth were covered with wax leaving three separate windows on the buccal surfaces. The enamel in one window was acid-etched, in the second window demineralized, and in the third window demineralized and subsequently acid-etched. In Test group 1, containing ten teeth, a defined enamel area on the buccal surfaces was acid-etched and sealed. The sealed area and a border of sound enamel around it were subjected to the demineralizing procedure. In Test group 2, a defined enamel window of 13 teeth was demineralized and subsequently etched and sealed. The sealed area and a border of surrounding enamel were subjected to a new cycle of demineralization. The longitudinal, bucco-lingual sections were examined in polarized light. When placed on acid-etched surfaces, the resin adhered firmly to the enamel with no evidence of demineralization or enlargement of previously demineralized areas underneath the sealants.  相似文献   
34.
All episodes of Clostridium difficile associated diarrhea (CDAD) diagnosed in a defined population of 274,000 including one tertiary and two primary hospitals and their catchment areas were studied during 12 months. The annual CDAD incidence in the county was 97 primary episodes per 100,000, and 78% of all episodes were classified as hospital associated with a mean incidence of 5.3 (range, 1.4 to 6.5) primary episodes per 1,000 admissions. The incidence among hospitalized individuals was 1,300-fold higher than that in the community (33,700 versus 25 primary episodes per 100,000 persons per year), reflecting a 37-fold difference in antibiotic consumption (477 versus 13 defined daily doses [DDD]/1,000 persons/day) and other risk factors. Three tertiary hospital wards with the highest incidence (13 to 36 per 1,000) had CDAD patients of high age (median age of 80 years versus 70 years for other wards, P < 0.001), long hospital stay (up to 25 days versus 4 days), or a high antibiotic consumption rate (up to 2,427 versus 421 DDD/1,000 bed days). PCR ribotyping of C. difficile isolates available from 330 of 372 CDAD episodes indicated nosocomial acquisition of the strain in 17 to 27% of hospital-associated cases, depending on the time interval between index and secondary cases allowed (2 months or up to 12 months), and only 10% of recurrences were due to a new strain of C. difficile (apparent reinfection). In other words, most primary and recurring episodes were apparently caused by the patient's endogenous strain rather than by one of hospital origin. Typing also indicated that a majority of C. difficile strains belonged to international serotypes, and the distribution of types was similar within and outside hospitals and in primary and relapsing CDAD. However, type SE17 was an exception, comprising 22% of hospital isolates compared to 6% of community isolates (P = 0.008) and causing many minor clusters and a silent nosocomial outbreak including 36 to 44% of the CDAD episodes in the three high-incidence wards.  相似文献   
35.

OBJECTIVES:

The aim of this study was to determine the antiproliferative and apoptotic effects of hot water extracts of Chlorella vulgaris on hepatoma cell line HepG2.

INTRODUCTION:

The search for food and spices that can induce apoptosis in cancer cells has been a major study interest in the last decade. Chlorella vulgaris, a unicellular green algae, has been reported to have antioxidant and anti‐cancer properties. However, its chemopreventive effects in inhibiting the growth of cancer cells have not been studied in great detail.

METHODS:

HepG2 liver cancer cells and WRL68 normal liver cells were treated with various concentrations (0‐4 mg/ml) of hot water extract of C. vulgaris after 24 hours incubation. Apoptosis rate was evaluated by TUNEL assay while DNA damage was assessed by Comet assay. Apoptosis proteins were evaluated by Western blot analysis.

RESULTS:

Chlorella vulgaris decreased the number of viable HepG2 cells in a dose dependent manner (p < 0.05), with an IC50 of 1.6 mg/ml. DNA damage as measured by Comet assay was increased in HepG2 cells at all concentrations of Chlorella vulgaris tested. Evaluation of apoptosis by TUNEL assay showed that Chlorella vulgaris induced a higher apoptotic rate (70%) in HepG2 cells compared to normal liver cells, WRL68 (15%). Western blot analysis showed increased expression of pro‐ apoptotic proteins P53, Bax and caspase‐3 in the HepG2 cells compared to normal liver cells WRL68, and decreased expression of the anti‐apoptotic protein Bcl‐2.

CONCLUSIONS:

Chlorella vulgaris may have anti‐cancer effects by inducing apoptosis signaling cascades via an increased expression of P53, Bax and caspase‐3 proteins and through a reduction of Bcl‐2 protein, which subsequently lead to increased DNA damage and apoptosis.  相似文献   
36.
Masir N, Ghoddoosi M, Mansor S, Abdul‐Rahman F, Florence C S, Mohamed‐Ismail N A, Tamby M‐R & Md‐Latar N H
(2012) Histopathology  60, 804–815 RCL2, a potential formalin substitute for tissue fixation in routine pathological specimens Aims: To investigate RCL2 as a fixative for tissue fixation in routine histopathological examination and to assess tissue suitability for ancillary investigations. Methods and results: Forty‐nine samples from 36 fresh specimens were cut into three equal pieces and fixed in RCL2 diluted in 100% ethanol, RCL2 in 95% ethanol, or neutral buffered formalin as control. Suitability for microtomy, quality of histomorphology, histochemistry, immunohistochemistry, fluorescent and silver in‐situ hybridization analysis and extracted genomic DNA were assessed. Microtomy was straightforward in most tissue blocks, but there was difficulty in cutting in approximately a quarter of samples, which required careful handling by an experienced technician. There were no significant differences in tissue morphology between RCL2‐ and formalin‐fixed tissues (P = 0.08). Generally, the quality of histochemical staining, immunohistochemistry and in‐situ hybridization were comparable to that of formalin‐fixed tissues. Inconsistent immunoreactivity was noted, however, with antibodies against pan‐cytokeratin and progesterone receptor. Genomic DNA concentration was higher in RCL2‐fixed tissues. Using RCL2 diluted in 95% ethanol did not affect fixation quality. Conclusion: RCL2 is a potential formalin substitute suitable as a fixative for use in routine histopathological examination; however, difficulty in microtomy and occasional discrepancies in immunohistochemical reactivity require further optimization of the methodology.  相似文献   
37.

Objective

To evaluate how patients are supported with information and other forms of Web-based decision support for making an informed choice of a primary health care provider.

Methods

The article is based on a comparative case study of recently developed tools provided by Web portals in Sweden (one national, three regional). The theoretical framework for analysis is the general calculation model, including the steps of isolating, examining, and ranking available options.

Results

The provision of information and other forms of support is reasonable when it comes to isolating a particular alternative or presenting a general view of alternatives. As for examining and ranking, one regional system and one national system offer support based on information from patient surveys and waiting times, and one regional system offers support based on provider competencies.

Conclusion

One design alternative is to represent the opinions of patients about care centers, another is to represent the characteristics of care centers, and a third is to combine the two. The general calculation model is relevant as a framework for analysis from a practical as well as a theoretical viewpoint.

Practical implications

The study provides practical examples of decision support for patient choice in primary health care.  相似文献   
38.

Background

Continuous prevention efforts for human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) are recommended among those men who have sex with men (MSM). Creative use of e-technologies coupled with a better understanding of social networks could lead to improved health interventions among this risk population.

Objective

The aims of the study were to (1) compare the impact of various advertising strategies on recruiting MSM participants to an online HIV/AIDS survey, and (2) explore the feasibility of using a social network service (SNS) for study advertising.

Methods

A cross-sectional online survey was conducted in 2009. South Australian men over 18 years were invited to participate if they had had sexual intercourse with men in the previous year. A short questionnaire was used to collect demographics and information on sexual behavior, HIV history, use of the Internet for dating purposes, and sources of health information. The survey was promoted in community settings and online, including advertisements through social networks.

Results

A total of 243 men completed the online survey during the 8-week data collection period. Online advertisements recruited 91.7% (220/240) of the sample. Conversely, traditional advertisements in the community recruited only 5.8% (14/240) of the sample. Ten volunteers were asked to advertise on their personal SNS application, but only 2 effectively did so. Only 18/240 (7.5%) of the respondents reported having learned of our study through the SNS application. In this sample, 19.3% (47/243) of participants had never been tested for HIV. Among the participants who had been tested, 12.8% (25/196) reported being HIV-positive. Regarding Internet use, 82.3% (200/243) of participants had dated online in the previous 6 months. Among the participants who had dated online, most (175/200, 87.5%) had found an Internet sexual partner and two-thirds (132/200, 66.0%) had had anal sex with these partner(s). Among men who had anal sex with an Internet partner, 68.2% (90/132) used a condom during sex.

Conclusions

The MSM participants in this study had high-risk profiles for HIV and other sexually transmitted diseases (STDs), which highlights the need for ongoing health interventions among this group. In this study, the SNS marketing strategy did not appear to create a viral effect and it had a relatively poor yield.  相似文献   
39.

Objective:

To optimize the delay time before the initiation of arterial phase scan in the detection of focal liver lesions in contrast enhanced 5 phase liver CT using the bolus tracking technique.

Patients and Methods:

Delay - the interval between threshold enhancement of 100 hounsfield unit (HU) in the abdominal aorta and commencement of the first arterial phase scan. Using a 16 slice CT scanner, a plain CT of the liver was done followed by an intravenous bolus of 120 ml nonionic iodinated contrast media (370 mg I/ml) at the rate of 4 mL/s. The second phase scan started immediately after the first phase scan. The portal venous and delay phases were obtained at a fixed delay of 60 s and 90 s from the beginning of contrast injection. Contrast enhancement index (CEI) and subjective visual conspicuity scores for each lesion were compared among the three groups.

Results:

84 lesions (11 hepatocellular carcinomas, 17 hemangiomas, 39 other hypervascular lesions and 45 cysts) were evaluated. CEI for hepatocellular carcinomas appears to be higher during the first arterial phase in the 6 seconds delay group. No significant difference in CEI and mean conspicuity scores among the three groups for hemangioma, other hypervascular lesions and cysts.

Conclusion:

The conspicuity of hepatocellular carcinomas appeared better during the early arterial phase using a bolus tracking technique with a scan delay of 6 seconds from the 100 HU threshold in the abdominal aorta.  相似文献   
40.
Ginger (Zingiber officinale Rosco) is widely used in foods as a spice all around the world. It has been reported to have antioxidant and anticarcinogenic properties. We investigated the effect of ginger in ethionine induced rat hepatocarcinogenesis. Male Wistar rats were divided into 5 groups: group 1 and 2 served as controls and they received normal rat chow and olive oil respectively. Group 3 was fed with ginger oleoresin dissolved in olive oil at 100 mg/kg body wt. Group 4 was fed with choline deficient diet and 0.1% ethionine in drinking water (CDE diet), and group 5 received ginger with CDE diet. Blood samples were taken from the orbital sinus at 0 and 8 weeks of experiment for the determination of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase and lipid peroxidation end product, malondialdehyde (MDA). Rats were also killed at 8 weeks for the observation of liver tumor formation. CDE diet induced the formation of liver nodules in rats and increased SOD activity. However, it had no effect on catalase, GPx and MDA levels when compared to both controls at 8 weeks of experiment. When CDE rats were treated with ginger, the formation of liver tumour, SOD activity and MDA level reduced, catalase activity was increased but no change was observed for GPx activity when compared to CDE group. In conclusion, ginger supplementation suppressed liver carcinogenesis by scavenging the free radical formation, and by reducing lipid peroxidation.  相似文献   
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