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81.
Objectives: The aims of the current study were: (1) to assess the prevalence of oral habits, bruxism, and temporomandibular disorders (TMDs) among children living in Uganda; (2) to establish whether parafunctional activities are associated with TMDs; and (3) to examine the possible impact of gender and age on the prevalence of bruxism, oral habits, and TMDs.

Methods: This study included 153 children aged 6–17 years. The study consisted of a questionnaire and a clinical examination.

Results: TMDs were moderately prevalent (35%). Parafunctional habits were performed by 93% of the participants. When performed extensively, they were significantly related to myalgia. No gender or age significant differences were found.

Conclusions: 1. Only extensive masticatory parafunctional oral activity is significantly related to myalgia. 2. Gender and age had no impact on the prevalence of bruxism, oral habits, or TMDs. 3. Sleep and awake bruxism were not related to anamnestic symptoms or clinical findings in TMD.  相似文献   

82.
A variety of (super)paramagnetic contrast agents are available for enhanced MR visualization of specific tissues, cells, or molecules. To develop alternative contrast agents without the presence of metal ions, liposomes were developed containing simple bioorganic and biodegradable compounds that produce diamagnetic chemical exchange saturation transfer MR contrast. This diamagnetic chemical exchange saturation transfer contrast is frequency-dependent, allowing the unique generation of "multicolor" images. The contrast can be turned on and off at will, and standard images do not show the presence of these agents. As an example, glycogen, L-arginine, and poly-L-lysine were encapsulated inside liposomes and injected intradermally into mice to image the lymphatic uptake of these liposomes. Using a frequency-dependent acquisition scheme, it is demonstrated that multicolor MRI can differentiate between different contrast particles in vivo following their homing to draining lymph nodes. Being nonmetallic and bioorganic, these diamagnetic chemical exchange saturation transfer liposomes form an attractive novel platform for multicolor imaging in vivo.  相似文献   
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The distinction between benign polyclonal and malignant monoclonal lymphoid disorders by morphology or immunophenotyping is frequently difficult. Therefore, the demonstration of clonal B-cell or T-cell populations by detecting identically rearranged immunoglobulin (Ig) or T-cell receptor (TCR) genes is often used to solve this diagnostic problem. Whereas the detection of rearranged Ig genes is well established, TCR gamma (gamma) and beta (beta) gene rearrangements often escape detection with the currently available polymerase chain reaction (PCR) assays. To establish a sensitive, specific, and rapid method for the detection of rearranged TCR-beta genes, we developed a new PCR approach with family-specific Jbeta primers and analyzed the resulting PCR products by high-resolution GeneScan technique. The superior efficiency of this new method was demonstrated by investigating 132 DNA samples extracted from lymph node and skin biopsy specimens (mostly formalin fixed) and blood samples of 62 patients who had a variety of T-cell lymphomas and leukemias. In all but 1 of the tumor samples (98.4%) a clonal amplificate was detectable after TCR-beta PCR and the same clonal T-cell population was also found in 15 of 18 (83%) of the regional lymph nodes and in 7 of 11 (64%) of the peripheral blood samples. Direct comparison of these results with those obtained currently by the most widely applied TCR-gamma PCR revealed an approximate 20% lower detection rate in the same set of samples than with the TCR-beta PCR method. These results indicate that the new TCR-beta PCR is most suitable for a rapid and reliable detection of clonal T-cell populations. (Blood. 2000;96:640-646)  相似文献   
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The prevalence rates and correlates of antihypertensive drug use among individuals with hypertension were determined using data derived from five biennial population-based surveys conducted between 1981 and 1990 in two New England communities. Point prevalence estimates were determined for nine categories of antihypertensive agents at five time points, and were analyzed by age and sex using multiple logistic regression. In the first cross-sectional survey, the prevalence of use per 1000 individuals with hypertension was 235.4 for diuretics, 57.1 for β-blockers, 65.5 for combination products, 29.2 for central α-agonists, 2.8 for peripheral α-antagonists, and 8.4 each for adrenergic blockers and direct vasodilators. The prevalence rates for calcium channel blockers and angiotensin-converting enzyme inhibitors increased sharply between the third and fourth survey cycles. Significant age- and sex-related differences in antihypertensive use were detected.  相似文献   
88.
Objective. Spinal cord stimulator (SCS) parameter settings have been well studied; however, the goal of this exploratory study was to examine the SCS parameters used during intra‐operative stimulation (IOS) at trial lead placement. Methods. In this retrospective study, we report the IOS parameter settings for 22 patients who underwent thoracic SCS lead trial for treatment of refractory low back and/or leg pain. Results. Paresthesia coverage was shown to differ depending upon the pain syndrome and the region involved (back and/or leg, p = 0.03). Certain stimulation parameters were demonstrated to be linked, including pulse width with rate (p = 0.04) and bipolar activation distance with amplitude (p < 0.01). Important variations in field configuration practice patterns also emerged. Conclusions. Larger prospective studies are required to confirm and extend the current results. The ultimate goal for this report is to establish a foundation for future studies to create an evidence‐based standardized algorithm for IOS to enhance the success rate of SCS trial screening.  相似文献   
89.
Using a rapid, simple and sensitive radioreceptor assay, a Ca2+-dependent K+-evoked release of endogenous GABA was demonstrated from rat cortical and hippocampal slices in vitro. This evoked-release of endogenous GABA was similar to tha of [3H]GABA release (in its Ca2+ dependency) but differed from the latter in having a higher signal to noise level. Neither 5-HT nor a stable enkephalin analogue had any effect on endogenous GABA release from hippocampus slices.  相似文献   
90.
When treated with formaldehyde, Tween 80, sodium oleate and Nonidet P-40, avian infectious bronchitis virus, porcine transmissible gastroenteritis virus, neonatal calf diarrhea coronavirus, porcine hemagglutinating encephalomyelitis virus as well as the human coronavirus show similar inner structures by negative staining. The first one is an inner membranous bag. This structure could be evaginated following treatments used and does not show the characteristic projections of coronaviruses. Subsequently, the inner fold could be separated from the outer membrane at the point of junction between these two membranes. Each virus does not react in the same way to the action of the different products. The transmissible gastroenteritis virus appears more sensitive to treatments than other viruses. On the other hand, the hemagglutinating encephalomyelitis virus is the most resistant. The variable sensitivities of these viruses are not related to the type of host-cells. Also, a second internal structure, which is more dense than the viral particle, encircles partially the aperture of the internal tongue-shaped structure and seems to emerge from the viral particle through the aperture of the inner bag.  相似文献   
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