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61.
Context. Hypericum species including Hypericum confertum Choisy, H. hircinum L., H. hyssopifolium Chaix. subsp. elongatum (Ledeb.) Woron var. microcalycinum (Boiss. &; Heldr.) Boiss. and H. perforatum L. (Clusiaceae) are used as medicinal plants in Turkey.

Objective: The anti-angiogenic evaluation of Hypericum essential oils using the chick embryo chorioallantoic membrane (CAM) assay are performed with this study for the first time.

Materials and methods: The anti-angiogenic activity of Hypericum essential oils (0.5–5.0?mg/ml) was evaluated in vivo using the CAM assay, compared to standard anti-angiogenic substances at the same concentrations, in trice replicated independent assays. GC and GC-MS analyses were carried out simultaneously to identify the chemical compositions of the Hypericum essential oils.

Results: The CAM treated with H. perforatum essential oil showed anti-angiogenic effect (score 0.6?±?0.3) at 50?µg/pellet concentration, whereas other tested Hypericum essential oils showed no effect compared to the standards (e.g. suramin score 0.5?±?0.2). Furthermore, the tested oils showed neither membrane toxicity nor irritation at the tested concentrations. The major compound of the essential oil of H. confertum was identified as germacrene D (30.2%). The major compound of the essential oils of the H. hircinum. H. hyssopifolium subsp. elongatum var. microcalycinum and H. perforatum was identified as α-pinene (88.3, 57.8, 33.3%), respectively.

Discussion and conclusion. Hypericum species and in particular H. perforatum essential oil may have important effect toward wound healing and various inflammations. The data obtained in this experiment suggest further investigations on various cancers due to its anti-angiogenic effects observed.  相似文献   
62.
(1) It is estimated that 10% of the world’s population will need a dental implant in their lifetime. Despite all the advances in the comprehension of dental implant designs, materials and techniques, traditional implants still have many limitations. Customized root-analogue implants are, therefore, gaining increased interest in dental rehabilitation and are expected to not only preserve more hard and soft tissues but also avoid a second surgery and improve patient overall satisfaction. In this sense, the aim of this review was to collect and analyse the clinical trials and case reports on customized root-analogue implants available in the literature; (2) This review was carried out according to the PRISMA Statement. An electronic database search was performed using five databases: PubMed, Google Scholar, Medline, Science Direct, and Scopus. The following keywords were used for gathering data: custom-made, dental implants, root-analogue, anatomical, customized and tooth-like; (3) 15 articles meeting the inclusion criteria—articles reporting clinical trials, case reports or animal studies and articles with root-analogue implants and articles with totally customized implant geometries—were selected for the qualitative synthesis. The design and manufacturing techniques, implant material and surface treatments were assessed and discussed; (4) The performance of some root-analogue implants with specific features (i.e., macro-retentions) was successful, with no signs of infection, periodontitis nor bleeding during the follow-up periods.  相似文献   
63.

Background

The incidence of asymptomatic pulmonary Mycobacterium avium complex (MAC) disease appears to be increasing. This study aimed to determine the clinical characteristics and examine early outcomes of patients newly diagnosed with MAC disease.

Methods

We retrospectively reviewed the medical records of all 184 patients newly diagnosed with MAC disease between April 2013 and March 2015 at our hospital. Culture conversion, defined as at least two consecutive negative cultures, was used as the early outcome measure.

Results

Of 184 patients, 45 were male and 139 were female, with a mean age of 70 years. Abnormal chest shadow found during an annual health check-up (58 patients) or incidentally during visits for other diseases (72 patients), was the major reason for referral to hospital, typically with no symptoms. Anti-MAC IgA antibody was positive in 64.5% of patients, and the positive rate was associated with the extent of lesions. Clarithromycin-based multi-drug chemotherapy was initiated in 111 patients. Culture conversion was achieved in 61 of 82 (74.4%) patients who were able to continue multi-drug chemotherapy. Patients who achieved culture conversion were more likely to be younger, female, and have a lower smear grade and nodular-bronchiectatic type. Multivariate logistic regression analysis identified patient age and smear grade as predictive variables.

Conclusions

Abnormal chest shadow found during health check-up was the major reason for hospital visits, and most were asymptomatic. Culture conversion was achieved in three-fourths of patients treated, and was associated with age and smear grade, supporting early intervention at a younger age.  相似文献   
64.
All‐ceramic crowns for teeth are widely used for restoring teeth. Stone casts have been made from conventional impression methods; however, newer techniques have made this process easier and faster for both the patient and the practitioner. Laboratory CAD/CAM technology mainly involves scanning the die stone, while other systems permit impression or intraoral scanning; however, one major concern remaining is the marginal fit of the restorations made using different methods for recording the prepared teeth. This study aims to review studies evaluating the marginal fit of all‐ceramic crowns manufactured by CAD/CAM systems using different extra‐ and intra‐oral scanners compared to conventional impressions.  相似文献   
65.
One problem that may arise in full‐coverage restorations is clinical crown fracture. Fracture of an endodontically treated and crowned tooth in the esthetic zone may be embarrassing to both the patient and clinician. If a completely sound margin and at least 2 mm of coronal structure remain, a fractured tooth may possibly be retreated by a repair. Several methods have been introduced to reproduce the original contour of the tooth for retrofitting an existing crown. If an existing crown is used as a template, excessive core material may remain over the margin, as loading the proper amount of core material is difficult, and making vent holes on the existing crown is not feasible. This article presents a repair technique to reuse an existing crown with computer‐aided design and computer‐aided manufacturing (CAD/CAM) technology. By using a milled poly(methylmethacrylate) matrix, the mentioned limitations are eliminated, and the original contour of the tooth can be effectively restored with minimal intervention. As an existing crown is reused, the issues of additional time and cost for repreparation, reimpression, and new crown are eliminated.  相似文献   
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BACKGROUND:

Despite a high prevalence of complementary alternative medicine (CAM) use among inflammatory bowel disease (IBD) patients, there is a dearth of information about the attitudes and perceptions of CAM among the gastroenterologists who treat these patients.

OBJECTIVE:

To characterize the beliefs, perceptions and practices of gastroenterologists toward CAM use in patients with IBD.

METHODS:

A web-based survey was sent to member gastroenterologists of the Canadian Association of Gastroenterology. The survey included multiple-choice and Likert scale questions that queried physician knowledge and perceptions of CAM and their willingness to discuss CAM with patients.

RESULTS:

Fifty-three per cent of respondents considered themselves to be IBD subspecialists. The majority (86%) of gastroenterologists reported that less than one-half of their patient population had mentioned the use of CAM. Only 8% of physicians reported initiating a conversation about CAM in the majority of their patient encounters. Approximately one-half (51%) of respondents were comfortable with discussing CAM with their patients, with lack of knowledge being cited as the most common reason for discomfort with the topic. Most gastroenterologists (79%) reported no formal education in CAM. While there was uncertainty as to whether CAM interfered with conventional medications, most gastroenterologists believed it could be effective as an adjunct treatment.

CONCLUSION:

Our findings demonstrate that gastroenterologists were hesitant to initiate discussions about CAM with patients. Nearly one-half were uncomfortable or only somewhat comfortable with the topic, and most may benefit from CAM educational programs. Interestingly, most respondents appeared to be receptive to CAM as adjunct therapy alongside conventional IBD treatment.  相似文献   
70.
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