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41.
Two adhesive systems, Transbond APC II (3M Unitek, Monrovia, Calif) and Quick Cure (Reliance Orthodontic Products, Itasca, Ill), were used to determine the efficacy of precuring the liquid resin primer phase of the systems to increase shear bond strength. One hundred sixty bovine incisors were divided into groups of 20 specimens. In 1 group, the primer was cured before placement of the bracket with the filled adhesive material, and, in the other group, the primer was not precured. The shear-peel bond strength was tested with a testing machine at 30 minutes and 24 hours. No statistically significant difference in bond strength was found between the groups that had or had not been precured. More adhesive remained on the teeth with the Transbond when the primer was not precured. There is no advantage or disadvantage in bracket bond strength by precuring the primer before placing the bracket and filled component of the adhesive.  相似文献   
42.
Knowledge of the molecular events that occur in carious disease has so far been constrained due to difficulties in obtaining sufficient quantities of the dental tissues and cells involved. Our histological findings indicate that a pulp-odontoblast cellular complex can be obtained from carious and healthy human teeth when exposed to low-temperatures prior to pulpal extirpation and from rodent teeth processed at room-temperature. In contrast, pulpal tissue extracted from room-temperature processed human teeth and low-temperature processed rodent teeth resulted in the odontoblast layer remaining attached to the pulp chamber. Semi-quantitative RT-PCR (sq-RT-PCR) analysis confirmed that markers previously shown to be preferentially expressed in odontoblasts, namely dentin sialophosphoprotein (DSPP) and Nestin, amplified more readily from the extracted pulp-odontoblast complex, as compared to pulpal tissue alone, in both human and rodent samples. Subsequent gene expression analysis of collagen-1alpha and collagen-3alpha indicated levels were significantly higher in carious pulpal tissue. In addition, analysis characterising the expression of members of the transforming growth factor and bone morphogenic protein families and their receptors indicated in general, that these genes were expressed by healthy odontoblasts and up-regulated in both pulpal cells and odontoblasts in response to carious injury. Use of this temperature-sensitive dental tissue preparation procedure allows detection of differential gene expression in odontoblasts and other pulpal cells in healthy and carious tissue.  相似文献   
43.
Facial pain can, on rare occasions, be the presenting symptom of lung cancer. This report describes a patient with non-metastatic lung cancer, which was associated with attacks of debilitating facial pain, presenting as cluster headache. Moreover, 32 reported cases of lung cancer-related facial pain (including the present one) are reviewed, and their clinical features are summarized. The facial pain is almost always unilateral, and is most commonly localized to the ear, the jaws, and the temporal region. The pain is frequently described as severe and aching, and may be continuous or intermittent. Aggravation and expansion of the pain, digital clubbing, increased erythrocyte sedimentation rate, and hypertrophic osteopathy, may contribute to the diagnosis. Referred pain, due to invasion or compression of the vagus nerve, as well as paraneoplastic syndrome secondary to the production of circulating humoral factors by the malignant tumor cells, is implicated in the pathophysiology of facial pain associated with non-metastatic lung cancer. Radiotherapy and tumor resection with vagotomy are very effective in aborting the facial pain. Thus, lung cancer should be included in the differential diagnosis of facial pain that is atypical and/or refractory to treatment.  相似文献   
44.
Development of common core curricula for the graduate advanced education/specialty programs in dental schools presents significant challenges. Similarities in graduate education accreditation standards justify such an approach, yet a core curriculum is difficult to achieve for a variety of reasons including scheduling constraints and the capacity of a common, single pathway curriculum to address the specific educational needs of postgraduate students in different disciplines. Additionally, many dental schools are experiencing severe shortages of qualified faculty to provide graduate program instruction. There are no previous reports regarding graduate core curricula and the definition/delivery of such core curricula in advanced education programs in dentistry although there are several reports in the medical literature that support the educational value of a unified core curriculum implemented in a modular format. Graduate curricula are typically designed to provide residents with advanced education/training beyond what is acquired during their predoctoral dental school experience. Advanced education programs must emphasize knowledge and skills that are discipline-specific; however, there is a large amount of common foundational material within the early phases of these programs. Dental schools have attempted to identify and present this common material within the context of an organized shared set of courses/seminars where residents from each advanced education program are scheduled simultaneously. However, there have been problems with the implementation of a shared core curricula including the following: 1) dissimilar educational backgrounds/abilities among residents; 2) relevance of material to all residents; 3) lack of central management; 4) scheduling conflicts; and 5) lack of adequate and consistent program evaluation. In an attempt to resolve these problems, a new comprehensive graduate core curriculum was implemented at the Marquette University School of Dentistry in 2000. This core curriculum was designed to 1) be user-friendly; 2) allow flexibility; 3) meet specific programmatic/accreditation needs for each advanced education program; and 4) provide assessment tools for continuous resident feedback and curriculum improvement. Assessment data obtained from residents, faculty, and program directors indicate that this approach has been successful and has transformed graduate education at Marquette. Thus, this model may prove useful for other institutions seeking to refine or develop graduate core curricula.  相似文献   
45.
Purpose

To describe a successful five-level cervical corpectomy and circumferential reconstruction in a patient with a plexiform neurofibroma causing a severe kyphotic deformity.

Methods

Case report.

Results

43-year-old man with history of Neurofibromatosis presented with signs and symptoms of myelopathy with spastic lower extremities and gait difficulties. Imaging studies demonstrated a severe kyphotic deformity of the cervical spine with associated cord compression secondary to an anteriorly positioned plexiform neurofibroma. Two-stage surgical procedure was designed to treat this lesion. Stage I consisted of tracheostomy placement, transmandibular, circumglossal approach to the anterior cervical spine, C2–C6 corpectomies, and C1–C7 reconstruction with a custom titanium cage/plate. Stage II consisted of suboccipital craniectomy, C1–C2 laminectomies, and occipital-cervical thoracic instrumented fusion (O-T8). There were no operative complications, but the patient did develop a small pulmonary embolism post-operatively treated with anticoagulation. Patient required two-weeks of inpatient rehabilitation following surgery. Gastrostomy tube and tracheostomy were successfully discontinued with preserved swallowing and respiratory function. Patient-reported outcome measurements revealed significant and sustained improvement post-operatively.

Conclusions

Five-level cervical corpectomy including C2 can be safely and successfully performed via a transmandibular, circumglossal approach. Circumferential reconstruction utilizing a custom anterior titanium cage and plate system manufactured from a pre-operative CT scan was utilized in this case. Long segment occipital-cervical-thoracic reconstruction is recommended in such a case. Using such a technique, improvement in myelopathy, correction of deformity, and improved quality of life can be achieved.

  相似文献   
46.
Oxytocin (OT) and arginine vasopressin (AVP) exert robust influence on social affiliation and specific cognitive processes in healthy individuals. Abnormalities in these neuroendocrine systems have been observed in psychotic disorders, but their relation to impairments in behavioral domains that these endocrines modulate is not well understood. We compared abnormalities of OT and AVP serum concentrations in probands with schizophrenia (n = 57), schizoaffective disorder (n = 34), and psychotic bipolar disorder (n = 75); their first-degree relatives without a history of psychosis (n = 61, 43, 91, respectively); and healthy controls (n = 66) and examined their association with emotion processing and cognition. AVP levels were lower in schizophrenia (P = .002) and bipolar probands (P = .03) and in relatives of schizophrenia probands (P = .002) compared with controls. OT levels did not differ between groups. Familiality estimates were robust for OT (h 2 = 0.79, P = 3.97e−15) and AVP (h 2 = 0.78, P = 3.93e−11). Higher levels of OT were associated with better emotion recognition (β = 0.40, P < .001) and general neuropsychological function (β = 0.26, P = .04) in healthy controls as expected but not in any proband or relative group. In schizophrenia, higher OT levels were related to greater positive symptom severity. The dissociation of OT levels and behavioral function in all proband and relative groups suggests that risk and illness factors associated with psychotic disorders are not related to reduced OT levels but to a disruption in the ability of physiological levels of OT to modulate social cognition and neuropsychological function. Decreased AVP levels may be a marker of biological vulnerability in schizophrenia because alterations were seen in probands and relatives, and familiality was high.Key words: oxytocin, vasopressin, schizophrenia, bipolar disorder, emotion recognition  相似文献   
47.
48.
Supraspinal processes in humans can have a top‐down enhancing effect on nociceptive processing in the brain and spinal cord. Studies have begun to suggest that such influences occur in conditions such as fibromyalgia (FM), but it is not clear whether this is unique to FM pain or common to other forms of chronic pain, such as that associated with osteoarthritis (OA). We assessed top‐down processes by measuring anticipation‐evoked potentials and their estimated sources, just prior (< 500 ms) to laser heat pain stimulation, in 16 patients with FM, 16 patients with OA and 15 healthy participants, by using whole‐brain statistical parametric mapping. Clinical pain and psychological coping factors (pain catastrophizing, anxiety, and depression) were well matched between the patient groups, such that these did not confound our comparisons between FM and OA patients. For the same level of heat pain, insula activity was significantly higher in FM patients than in the other two groups during anticipation, and correlated with the intensity and extent of reported clinical pain. However, the same anticipatory insula activity also correlated with OA pain, and with the number of tender points across the two patient groups, suggesting common central mechanisms of tenderness. Activation in the dorsolateral prefrontal cortex was reduced during anticipation in both patient groups, and was related to less effective psychological coping. Our findings suggest common neural correlates of pain and tenderness in FM and OA that are enhanced in FM but not unique to this condition.  相似文献   
49.
There is limited large-scale empirical research into the working lives of adults who have an autism spectrum disorder with no co-occurring intellectual disability. Drawing on data from a national survey, this report describes the employment activities and experiences of 130 adults with Asperger’s Disorder (AD) and high functioning autism (HFA) in Australia. Outcome measures include current occupation; occupational skill level and alignment with educational attainment; type of job contract; hours of work; support received to find work; support received in the workplace; and positive and negative experiences of employment. The findings confirm and expand upon existing evidence that adults with AD and HFA, despite their capacity and willingness to work, face significant disadvantages in the labour market and a lack of understanding and support in employment settings.  相似文献   
50.
ObjectivesTreating high-risk prostate cancer (CaP) with definitive therapy improves survival. We evaluated whether having health insurance reduces racial disparities in the use of definitive therapy for high-risk CaP.Materials and methodsThe Surveillance, Epidemiology, and End Results Program was used to identify 70,006 men with localized high-risk CaP (prostate-specific antigen level >20 ng/ml or Gleason score 8–10 or stage>cT3a) diagnosed from 2007 to 2010. We used multivariable logistic regression to analyze the 64,277 patients with complete data to determine the factors associated with receipt of definitive therapy.ResultsCompared with white men, African American (AA) men were significantly less likely to receive definitive treatment (adjusted odds ratio [AOR] = 0.60; 95% CI: 0.56–0.64; P<0.001) after adjusting for sociodemographics and known CaP prognostic factors. There was a significant interaction between race and insurance status (Pinteraction = 0.01) such that insurance coverage was associated with a reduction in racial disparity between AA and white patients regarding receipt of definitive therapy. Specifically, the AOR for definitive treatment for AA vs. white was 0.38 (95% CI: 0.27–0.54, P<0.001) among uninsured men, whereas the AOR was 0.62 (95% CI: 0.57–0.66, P<0.001) among insured men.ConclusionsAA men with high-risk CaP were significantly less likely to receive potentially life-saving definitive treatment when compared with white men. Having health insurance was associated with a reduction in this racial treatment disparity, suggesting that expansion of health insurance coverage may help reduce racial disparities in the management of aggressive cancers.  相似文献   
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