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21.
A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition.  相似文献   
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The osteo-musculo-cutaneous trapezius flap has seen its indications in mandibular reconstruction reduced since the appearance of micro-anastomotic flaps. However, it may still be useful when the patient has marked atheroma contraindicating a free flap. While the arterial supply of this flap is well known, the same is not true for its venous drainage. The preservation of the accessory nerve and its limits in mandibular reconstruction has been little studied. We carried out a study on 30 subjects (60 cadaveric dissections of trapezius flaps) in order to address these questions. The study has been completed by a surgical series of five patients. The cadaveric study allowed demonstration of the variability of venous drainage of this flap, which depended on the external jugular vein in 80% of cases, the subclavian vein in 12% of cases and on both veins in about 8% of cases. The accessory nerve in one third of cases passed through the middle of the arteriovenous pedicle making its preservation impossible. The segment of the scapular spine allowed reconstruction of about 9 cm of mandible including the mental protuberance in 95% of cases. The surgical study confirmed the data of the cadaveric study and showed the value of this flap when free flaps are contraindicated.  相似文献   
24.
Summary We studied metatarsal growth in 600 metatarsal bones (60 pairs of feet) taken from 60 human fetuses (35 males and 25 females) ranging in age from 13 to 24 weeks postconception. The data obtained for the total length (TL) and for the ossified metatarsal length (OML) were correlated to fetal crown-rump length (C-R). The ossified metatarsal length presented a growth rate greater than the total length growth rate. There was no statistical difference between either the right and left metatarsals or males and females in total length and ossified metatarsal length growth during the period studied. We believe that metatarsal growth curves could be used to monitor fetal foot growth.
Résumé Nous avons étudié la croissance métatarsienne sur 600 métatarsiens (60 paires de pieds) provenant de 60 foetus humains (35 masculins et 25 féminins) dont l'âge varie de 13 à 24 semaines après la conception. Les données concernant la Longueur Totale et la Longueur Osseuse ont été corrélées à la Longueur Vertex-Coccyx. La Longueur Osseuse a présenté un rythme de croissance plus rapide que la Longueur Totale. Il n'y avait pas de différences significatives pour la croissance de la Longueur Osseuse ou de la Longueur Totale ni entre les métatarsiens droits et gauches, ni entre les foetus masculins et féminins durant la période étudiée. Nous pensons que les courbes de croissance métarsienne pourraient être utilisées pour suivre la croissance du pied fetal.
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25.
Pituitary tumors are the most common primary intracranial neoplasms. Although most pituitary tumors are considered typically benign, others can cause severe and progressive disease. The principal aims of pituitary tumor treatment are the elimination or reduction of the tumor mass, normalization of hormone secretion and preservation of remaining pituitary function. In spite of major advances in the therapy of pituitary tumors, for some of the most difficult tumors, current therapies that include medical, surgical and radiotherapeutic methods are often unsatisfactory and there is a need to develop new treatment strategies. Gene therapy, which uses nucleic acids as drugs, has emerged as an attractive therapeutic option for the treatment of pituitary tumors that do not respond to classical treatment strategies if the patients become intolerant to the therapy. The development of animal models for pituitary tumors and hormone hypersecretion has proven to be critical for the implementation of novel treatment strategies and gene therapy approaches. Preclinical trials using several gene therapy approaches for the treatment of anterior pituitary diseases have been successfully implemented. Several issues need to be addressed before clinical implementation becomes a reality, including the development of more effective and safer viral vectors, uncovering novel therapeutic targets and development of targeted expression of therapeutic transgenes. With the development of efficient gene delivery vectors allowing long-term transgene expression with minimal toxicity, gene therapy will become one of the most promising approaches for treating pituitary adenomas.  相似文献   
26.

Background  

The Internet has been increasingly utilized in biomedical research. From online searching for literature to data sharing, the Internet has emerged as a primary means of research for many physicians and scientists. As a result, Web-based surveys have been employed as an alternative to traditional, paper-based surveys. We describe DADOS-Survey, an open-source Web-survey application developed at our institution that, to the best of our knowledge, is the first to be compliant with the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). DADOS-Survey was designed with usability as a priority, allowing investigators to design and execute their own studies with minimal technical difficulties in doing so.  相似文献   
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The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho /rho° mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the β-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA, is localized in the mitochondria and expressed in response to inositol and choline. Received: 15 June / 15 July 1998  相似文献   
29.

Background  

Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process.  相似文献   
30.
OBJECTIVE: To assess the beliefs of climacteric women regarding their health, menopause, and hormone replacement therapy (HRT). DESIGN: Medical students asked to interview 526 healthy women, ranging from 40 to 64 years of age, between January and February of 2002. Of that number, 26 (4.9%) declined to participate in the interview. Thus, 500 women were interviewed about their beliefs and perceptions regarding their quality of life and health risks, as well as their opinions on menopause and HRT. RESULTS: The mean age of the sample was 53.3 +/- 6.2 years; 83.4% were postmenopausal, and 18.8% were HRT users. Of the women interviewed, 38.6% believed that their health was good. Although 78.8% thought that cancer is the main cause of death, 64% of them considered themselves to be at high risk for cardiovascular disease and osteoporosis. Most (64%) believed that menopause deteriorates the quality of life and that it increases cardiovascular risk (52.4%) and osteoporosis (72.0%). The HRT users perceived that they had better health status (48.9% v 36.2%, P < 0.02) and smaller cardiovascular risk (54.3% v 66.3%, P < 0.04) than did the nonusers; however, they ignored the preventive effect of estrogens in osteoporosis. CONCLUSIONS: Women believe that menopause deteriorates their health. The HRT users perceived themselves to be healthier and to have a smaller risk for cardiovascular disease.  相似文献   
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