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51.
Objectives: Mini-implants are used for orthodontic bone anchorage. The reasons for a potential instability or loss of the mini-implants during treatment are multiple. Among other factors, colonization of implants with pathogenic bacteria is discussed. Therefore, the microflora associated with successful and failed mini-implants has been screened.
Material and methods: A total of 76 mini-implants collected from 25 patients were observed during regular orthodontic treatment. Bacterial samples of eight failed and – exemplarily – four successful (control) cases were subjected to a universal Bacteria -directed real-time quantitative polymerase chain reaction for quantification in combination with a microarray-based identification of 20 selected species.
Results: The failure rate in the present investigation was 10.5%. The bacterial analysis did not reveal any major difference in the total amount or species composition between control and failed mini-implants. However, Actinomyces viscosus was found in four (100%) and Campylobacter gracilis in three (75%) stable controls, whereas both species were rarely found (12.5%) in failed implants.
Conclusions: In the present study, the peri-implant sulcus surrounding failed orthodontic mini-implants did not show a specific aggressive bacterial flora.  相似文献   
52.
An easy and rapid second-derivative spectrophotometric method for the simultaneous analysis of trimethoprime (TMP) and sulfamethoxazole (SM) is described. These drugs have been used as antibacterial against a wide spectrum of organisms and combinations of these drugs are commonly used for the treatment of a variety of infections. The most advantageous approach of this method is the use of HP-beta-CD, which allows to improve the performance of the second-derivative ultraviolet spectrophotometry. For both compounds, a shift of the absorption bands and variations of their intensity were observed. The calibration graphs were linear in the concentration range of TMP (1.92-19.2 microg ml(-1)) and SM (1.60-16.5 microg ml(-1)), the correlation coefficient for the calibration graphs was better than 0.9994 and the precision was satisfactory (CV%< 4.96) in HP-beta-CD solutions. The proposed method was successfully applied to the assay of commercial tablets. The results were compared to those obtained by second-derivative ultraviolet spectrophotometry in the absence of HP-beta-CD. Thereby, the details of the statistical treatment of the analytical data are also presented.  相似文献   
53.
BACKGROUND: Over at least the past ten years, measures aimed at health promotion and prevention among young adults and teenagers have been being implemented from different public institutions and, in a certain sense, on a sectorial basis. The overall objective is to assess how the different measures carried out by different Public Institutions with regard to Health Promotion and Prevention have an impact on the actual conduct and practices of teenagers and young adults within the 14-25 age range in the Autonomous Community of Madrid. METHODS: A study based on a structural or qualitative methodology was conducted using the discussion group method, eight groups having been formed and their comments analyzed. RESULTS: The young adults do not feel any health-related prevention "system" as such exists on not considering themselves to be the object thereof. In the opinion of the young adults, disease, confined to the physical body, is conceived as being a short-lived, temporary and readily remedied based on the technological advances current medicine has to offer. On the contrary, the diseases related to the psychological perspective (mental disease dissociated with the area of the medical and connected to the individual/personal area) arouse interest in so much as young people are highly vulnerable to these diseases. CONCLUSIONS: Any measure aimed at generating identification and, therefore, the active response of young people must entail creating a connection between young people and health, which, not based exclusively in providing information, is capable of putting a space of control of the youths with regard to their harmful practices into play whilst at the same time highlighting their taking responsibility for their own actions. Considering we believe it best to "redefine" the term "prevention" in terms nearer to those of maintaining, improving or regaining (in short-lived cases) health, to thus connote the idea of physical and mental well-being.  相似文献   
54.
The effects of acamprosate, a drug thought to interact with N-methyl-D-aspartate (NMDA) receptors in the central nervous system (CNS), were examined on the antinociceptive action of morphine, induction of tolerance to and physical dependence on morphine, and expression of the abstinence syndrome to the opiate in mice. For the induction of tolerance and dependence, morphine (300 mg/kg) was administered by means of a slow-release preparation. Single doses of acamprosate (50, 100, 200, or 400 mg/kg) administered 30 min before a test dose of morphine did not change the antinociceptive effects of morphine in drug-naive mice. The drug was also administered in repeated doses (50, 100, 200, or 400 mg/kg, 30 min before and 12 and 24 h after the priming dose of morphine) in order to evaluate its effects on the induction of tolerance; all doses assayed, except the 400 mg/kg, did not affect the intensity of tolerance. The acute administration of acamprosate (50, 100, 200, or 400 mg/kg, injected 30 min before naloxone to morphine-pretreated mice) did not affect the intensity of the abstinence behavior. However, the repeated administration of 100 mg/kg of acamprosate (30 min before and 12 and 24 h after the priming dose of morphine) decreased the intensity of physical dependence. The results of these studies suggest that acamprosate may have modulatory effects on glutamatergic neurotransmission participating in the adaptive mechanisms induced by chronic morphine treatment.  相似文献   
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BACKGROUND: Adequate intakes of calcium and vitamin D reduce bone loss and fracture risk in the elderly. Other nutrients also affect bone health, and adequate intakes may influence bone turnover and balance. OBJECTIVE: We compared the long-term effects on bone turnover markers and calciotropic hormones of a multinutrient supplement, a calcium and vitamin D supplement, and dietary instruction aimed at increasing calcium intake through foods. DESIGN: Ninety-nine healthy postmenopausal women participated in a 3-y, randomized trial, receiving either 1) supplemental calcium (1450 mg/d) and vitamin D [10 microg (400 IU)/d], 2) calcium, vitamin D, and other nutrients (multinutrient supplement), or 3) dietary instruction (dietary control group). Data are from 83 subjects who completed the trial. RESULTS: Increases over baseline in calcium intakes and serum 25-hydroxyvitamin D concentrations were sustained over 3 y in all treatment groups. Circulating parathyroid hormone concentrations were reduced at year 1 in all treatment groups but trended toward baseline thereafter. Bone turnover markers followed a similar pattern, and none of the changes in biochemical concentrations differed significantly between groups. CONCLUSIONS: All 3 interventions offer long-term feasibility for increasing calcium intake and serum 25-hydroxyvitamin D concentrations. The dietary addition of micronutrients implicated in skeletal physiology confers no obvious bone-sparing effect in healthy postmenopausal women beyond that of calcium and vitamin D alone. The attenuation over time in suppression of parathyroid hormone and bone turnover might help explain why nutrient intervention tends to have less of a bone-sparing effect than do skeletally active medications such as estrogen or bisphosphonates.  相似文献   
58.
OBJECTIVES: To assess the association between maternal caffeine consumption during pregnancy and low birth weight, prematurity and intrauterine growth retardation. METHODS: A case-control was carried out and 354 newborns of single labor with birthweight <2,500 g (cases) and 354 with birthweight >3,000 g (controls) were analyzed. Caffeine consumption was calculated based on daily consumption of coffee, soft drinks and tea. Results were adjusted using multiple logistic regression for the following confounders: mother's age, schooling, income, marital status, skin color, parity, smoking, previous low birthweight children, mother's pre-pregnancy weight, employment status, interval between pregnancies, prenatal care and high blood pressure. RESULTS: For caffeine consumption <300 mg/day and >300 mg/day, the adjusted odds ratios for low birthweight were: 0.72 (95%IC=0.45-1.25) and 0.47 (95%IC=0.24-0.92); prematurity: 0.59 (95%IC=0.32-1.09) and 0.32 (95%IC=0.15-0.72); and intrauterine growth retardation: 1.16 (95%IC=0.45-3.01) and 0.64 (95%IC=0.20-1.98), respectively. CONCLUSION: There was no association between caffeine consumption during pregnancy and low birthweight, prematurity and intrauterine growth retardation.  相似文献   
59.
Africa is the continent most severely affected by the global HIV-1 epidemic, with east and southern Africa in general more severely affected than west and central Africa. Differences in the spread of the epidemic can be accounted for by a complex interplay of sexual behaviour and biological factors that affect the probability of HIV-1 transmission per sex act. Sexual behaviour patterns are determined by cultural and socioeconomic contexts. In sub-Saharan Africa, some traditions and socioeconomic developments have contributed to the extensive spread of HIV-1 infection, including the subordinate position of women, impoverishment and decline of social services, rapid urbanisation and modernisation, and wars and conflicts. Populations in many parts of Africa are becoming trapped in a vicious circle as the HIV-1 epidemic leads to high mortality rates in young and economically productive age groups, and thus leads to further impoverishment. Interventions to control HIV-1 should not only target individuals, but also aim to change those aspects of cultural and socioeconomic context that increase the vulnerability to HIV-1 of people and communities.  相似文献   
60.
PURPOSE: To demonstrate the imaging characteristics of neuroendocrine tumors (NETs) of the pancreas in patients with von Hippel-Lindau (VHL) disease to establish diagnostic criteria. MATERIALS AND METHODS: Twenty-five patients with VHL disease and 29 surgically confirmed pancreatic NETs were included. Screening computed tomographic (CT) and/or magnetic resonance (MR) imaging findings were reviewed, and tumor number, diameter, growth rates (doubling time), location, presence of metastatic disease, and attenuation or enhancement properties were determined. RESULTS: Eighteen of 29 (62%) pancreatic NETs were smaller than 3.0 cm in diameter and enhanced homogeneously on contrast material-enhanced CT and MR images. No tumor smaller than 3.0 cm metastasized. Tumors 3.0 cm or larger (11 [38%] of 29) more often enhanced heterogeneously, and two of 11 were associated with hepatic metastases. Smaller (<3.0 cm) tumors displayed longer mean doubling times (mean, 927 vs 351 days) than did larger (> or =3.0 cm) tumors; however, there was considerable overlap. Fifteen (52%) tumors were located in the pancreatic head; eight (28%), in the tail; and six (21%), in the body. Ten (40%) patients with pancreatic NETs had associated pheochromocytomas, and 22 (88%) had no or mild pancreatic cystic disease, which is substantially more than the general population of patients with VHL disease. CONCLUSION: Pancreatic NETs in VHL have characteristic features at CT and MR imaging: Most are small, located in the pancreatic head, and enhance homogeneously. Tumors larger than 3.0 cm are prone to metastasize and enhance heterogeneously.  相似文献   
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