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941.
Summary Previous work has shown an age-related reduction in neuronal uptake of noradrenaline in the prostatic, but not in the epididymal portion of the rat vas deferens. In the present paper, the influence of ageing on the number of [3H]desipramine binding sites and on the effect of lithium on neuronal [3H]noradrenaline uptake were studied in the prostatic and epididymal portions of vasa deferentia from 4- and 20-month-old rats. The affinity for [3H]desipramine (K d values) in the epididymal and prostatic portions did not change with age. However, ageing reduced the maximal number of [3H]desipramine binding sites (Bmax values) in the prostatic, but not in the epididymal portion. Lithium potentiated neuronal [3H]noradrenaline uptake only in the prostatic portion and this potentiation was not changed by ageing. The results showed differences in neuronal noradrenaline uptake between the two portions of the vas deferens. Furthermore, the data suggest that the age-related reduction in neuronal uptake in the prostatic portion is due to a reduction in the number of neuronal uptake sites for noradrenaline. Correspondence to R. Pekelmann Markus at the above address  相似文献   
942.
Background: The innervation of skin and oral mucosa plays a major physiological role in exteroception. This innervation is also clinically relevant as sensory changes occur after neurosurgical procedures. Purpose: The goal of this study was to compare the perception of mechanical stimuli applied to the buccal mucosa in the vicinity of osseointegrated oral implants with that in the controlateral dentate side. The role of the previously reported increased innervation in the peri‐implant soft tissues in the oral sensorimotor function was thus examined. Materials and Methods: Seventeen subjects with 20 implants were tested. Directional cutaneous kinaesthesia (DCK) and graphesthesia (G) were performed on the buccal side of the alveolar mucosa before and at planned intervals after implant placement. The observation was pursued until 6 months after the prosthetic rehabilitation. In each subject, the contralateral mucosa served as a control to the implant sites. Average percentages of correct responses in a four‐choice task for DCK and a three‐choice task for G were calculated. Results: Despite an intersubject variation in both the DCK and G, high intraindividual correlations were found (p < .005). The implant sites showed a significant difference toward the control sites at the four interval test for both tests. For DCK and G, the average of correct responses decreased after abutment connection (i.e., after the implant uncovering surgery) to increase afterwards to reach a level close to, but still lower than, the control sites 3 to 6 months after the prosthetic rehabilitation. Conclusion: The DCK and G are simple but reliable sensory tests that can be easily applied in the oral region. This prospective study indicates that tooth loss reduces tactile function compared with implant‐supported prostheses. The peri‐implant soft tissues could be partially involved in the osseoperception function.  相似文献   
943.
The aim of this study was to evaluate the association between dental status and the prevalence and severity of osseous changes in the temporomandibular joints of human skulls from the Roman–Byzantine period. Fifty‐eight skulls from 36 men and 22 women between the ages of 19 and 63 years were studied, and the following parameters were evaluated: morphological osseous changes in the articular surface of the condyles, tooth wear and molar support. A significant correlation between age and dental wear or loss of molar support was observed, although no correlation was noted between age and morphological osseous changes in the condyles. The loss of molar support was significantly correlated with morphological osseous changes of the condyles, whereas no significant correlation was found between dental wear and condylar changes. This study demonstrates that the loss of molar support can serve as a predictor of osseous changes in the condyle. Reduced molar support may be one of the aetiologies associated with morphological osseous changes in temporomandibular joints. Further studies should to be performed to investigate this potential correlation.  相似文献   
944.
This histochemical study showed that experimentally arteriosclerotic rats, subjected to an occlusal stress of six weeks’ duration, showed an inflammation-related increase of chloride-activated arginine aminopeptidase and acid phosphata-se activity in the basal cells of the gingival epithelium. The activity of chloride-activated arginine aminopeptidase and acid and alkaline phosphatase in the gingival connective tissue was slight and suggestive of chronic inflammation. Biochemical comparison of gingival specimens from the stressed and unstressed sides of the jaw in the experimental animals failed to reveal any difference in the rate of N-L-arginyl-2-naphthylamide hydrolysis induced by the Cl-ion in connection with occlusal disorder. On the other hand, the mean value of the enzyme activity was lower in the experimental animals than the controls (p < 0.5). The difference was assumed to be associated with degenerative tissue changes. The hydrolysis of p-nitrophenyl phosphate at acidic and alkaline pH in the gingiva was higher in the experimental animals than in the controls, and in the alkaline pH range the difference between the mean values was statistically significant (p < 0.01). This finding, which may be associated not only with gingival inflammation but also with other tissue changes, requires further investigation.  相似文献   
945.
946.
Various therapies have been tried for psoriasis. In Japan, biologics began to be used for psoriasis treatment in January 2010. Their clinical efficacy is well known, but biologics cannot be used in all psoriasis patients for reasons such as side‐effects and cost. It is necessary to evaluate the effect of long‐term psoriasis treatment, but there have been no reports evaluating long‐term treatment. Therefore, the outcomes of patients who had been treated at the Tokai University Hospital for more than 5 years, before biological agents were released, were examined. Three categories, classified by initial severity, changes in severity by method of treatment and background characteristics, were investigated. In conclusion, cases of long‐term treatment with a combination of topical corticosteroid and topical vitamin D3 analog or oral cyclosporin were found to be effective therapies. Patients with a history of diabetes mellitus or cardiovascular disease of psoriasis were likely to be treatment resistant.  相似文献   
947.
The aim of this retrospective study was to investigate the amount of skeletal and dental expansion in patients submitted to surgically assisted rapid palatal expansion (SARPE). The sample consisted of 21 patients (14 female and seven male) with a mean age of 25.4 years (range 17.4–41.8 years). Postero-anterior (PA) cephalograms were taken pre-expansion (T1), immediately after expansion (T2), and at post-expansion retention of 120 days (T3). SARPE promoted significant transverse skeletal changes, which were maintained from T2 to T3. Dentoalveolar expansion and dental tipping were also observed in the region of the first molars and first premolars; however the net effect at the first molars was significantly less than that at the first premolars. No statistically significant effect on the width of the nasal cavity was observed. The findings indicate that peculiarities inherent to dental effects may influence the clinical options for SARPE. Skeletal expansions with SARPE were significant and stable. Dental changes were different between molars and premolars. The transverse changes after SARPE should be observed for future procedures related to the retention and the completion of orthodontic treatment.  相似文献   
948.
患儿女,4岁。口腔黏膜破溃、白斑2.5个月,全身出现皮疹半个月,加重4d。皮肤科情况:口角、口腔黏膜、舌体表面及两侧可见浅糜烂面及白色膜状物,面颈部、躯干四肢可见略密集的米粒至黄豆大的半球形丘疹,表面有蜡样光泽,中央有脐凹,手掌、足底可见同样皮疹。口腔分泌物真菌培养有白念珠菌生长。抗HIV抗体检测阳性。诊断:艾滋病;口腔念珠菌病。  相似文献   
949.
950.

Introduction

Alveolar ridge preservation (ARP) is a well-defined treatment performed to reduce bone dimensional changes occurring during the healing of post-extraction sockets to allow for adequate implant placement. Leukocyte and platelet-rich fibrin (L-PRF) has been showing to potentially promote bone and tissue regeneration during wound healing. Therefore, the aim of this study is to evaluate its efficacy for ARP when applied to fresh extraction sockets, in comparison with spontaneous healing.

Materials and Methods

Twenty-seven patients with hopeless non-molar teeth were treated. After randomization, fresh extraction sockets were either filled with L-PRF or allowed to heal spontaneously. CBCTs and intraoral scans were obtained immediately after extraction and at 4 months. Through superimposition of the obtained images, changes in the horizontal ridge width, height, buccal volume, and ridge contour changes were measured, as well as patient-reported outcome measures (PROM's).

Results

The ridge dimensions changed similarly in both groups. Although less reduction occurred in the test group at 1 mm from the bone crest, differences were not statistically significant (p > 0.05). Application of L-PRF did not prevent reductions of ridge contours, neither in the linear vertical aspect nor in volumetric changes. There were no differences between groups in the need for bone regeneration when placing implants. Patients in both groups reported similar outcomes in terms of bleeding, pain, inflammation, and function at 1 and 4 weeks postoperatively.

Conclusion

Alveolar preservation with L-PRF neither minimized bone resorption occurring after tooth extraction in non-molar sites nor reduced the need for bone regeneration when placing implants. Furthermore, its use did not improve PROM's.  相似文献   
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