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81.
BACKGROUND: The purpose of the present study was to assess the effects of adjunctive meloxicam on the matrix metalloproteinase-8 (MMP-8) levels of gingival crevicular fluid (GCF) in chronic periodontitis patients following the initial phase of periodontal therapy. METHODS: Twelve chronic periodontitis patients received 7.5 mg meloxicam, and 10 patients received placebo tablets together with scaling and root planing in a 1 x 1 regimen for 10 days. Scaling and root planing were performed on day 3 of drug intake. The MMP-8 levels in GCF samples obtained before and on day 10 of drug intake were determined by using the immunofluorescence assay. Plaque index (PI), papilla bleeding index (PBI), and GCF MMP-8 levels were compared within each patient group, between the 2 patient groups, and also with a clinically healthy control group using non-parametric statistical analyses. RESULTS: Both meloxicam and placebo groups showed statistically significant reductions in PBI, PI, and GCF MMP-8 levels on day 10 compared to baseline (P<0.01). The GCF MMP-8 level on day 10 in the meloxicam group was similar to the clinically healthy control group (P>0.05), while it was significantly higher in the placebo group (P<0.01). Positive correlations were found between MMP-8 total amounts and PBI scores at baseline and day 10 of drug intake in the patient groups. CONCLUSIONS: Meloxicam showed a tendency to reduce GCF MMP-8 levels in vivo within the first 10 days when used as an adjunct in the initial phase of periodontal treatment that consists of scaling and root planing. Verification of this effect on collagenase-2 downregulation, as well as on the clinical periodontal parameters in long-term studies using larger test and control groups, is needed to provide further support for the adjunctive use of selective cyclooxygenase (COX)-2 inhibitors in the treatment of chronic periodontitis.  相似文献   
82.
Granular cell tumor is an uncommon lesion usually located in the head and neck region (50%) with a female sex predominance. It is believed to be of primitive neuroectodermal origin. Typical clinical presentation is a small, uninflamed, slowly growing, yellowish mass approximately 2 cm in diameter. Granular cell tumor has a peculiar clinical behavior ranging from clearly benign, locally aggressive, or manifestly malignant. Treatment is surgical excision, but recurrences are possible. In this article, we present a case of recurrent benign granular cell tumor with the discussion of the treatment modalities. The patient was a 16-year-old girl with a 3-year history of a painless mass on the right side of her neck. The mass was excised two times at different centers and diagnosed as granular cell tumor after the pathologic examination. The time interval between the operations and recurrences was approximately 1 year. On physical examination, a yellowish, firm, nodular mass measuring approximately 2 x 1 cm was noted. Cervical lymph nodes were evaluated with ultrasonography preoperatively to exclude metastasis and no pathologic lymph nodes were noted. The lesion was excised under local anesthesia with a 1-cm safe margin and the resulting defect was closed primarily after undermining of the wound edges. Postoperatively, the wound began to heal with a hypertrophic scar and immediate precautions were taken. Topical steroid treatment and silicone blocks were applied. Now the patient is in the sixth postoperative month and followed up every month for signs of recurrence.  相似文献   
83.
Spinal cord dissemination over 10 years after surgical removal of the fourth ventricle ependymoma without local recurrence is extremely rare. A 49-year-old male underwent a macroscopically gross total removal of the fourth ventricle ependymoma and postoperative radiotherapy to the posterior fossa. Twelve years after the initial operation, the patient complained from uncontrolled fever attacks, low back pain and numbness of the legs. Spinal Magnetic Resonance Imaging revealed intradural extramedullary mass lesions located at the thoracic 2-3 and lumbar 5 vertebrae levels. Cerebrospinal fluid examination showed no tumour cells. He underwent total excision of these spinal lesions. Although the majority of the recurrences take place within a few years after surgery, we experienced a case with multiple spinal disseminations 12 years after the resection of the fourth ventricle ependymoma and administration of the radiation therapy to the posterior fossa. Up to our knowledge, this case represents the second unusual late recurrence reported in the literature. We conclude that low grade ependymomas should be followed neurologically and radiologically for more than 10 years after the initial treatment.  相似文献   
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85.
Summary Multi-unit spike triggered averaging was used to determine functional connectivity between spindle afferent fibers from the medial gastrocnemius muscle and the motoneurons innervating the medial (homonymous connections) and the lateral gastrocnemius-soleus muscle (heteronymous connections). As many as 288 possible connections between 24 motoneurons and 12 afferent fibers were studied in single, acute experiments. The influences of morphological and topographical factors, as well as of motoneuron species on functional connectivity were analysed. The probability that a motoneuron would receive functional connections from a given population of afferent fibers was related to its size and its proximity to the spinal entry level of the afferent fibers. The faster the axonal conduction velocity of the motoneuron (i.e. the larger the motoneuron) and the closer its location to the entry zone of the afferent fibers, the higher was its probability of receiving functional connections. The greater the conduction velocity (i.e. diameter) of a stretch receptor afferent fiber, the higher was its probability of making functional connections with motoneurons. These relationships were qualitatively similar for homonymous and heteronymous connections. 58% (233/399) of the Ia and group II afferents (combined) had functional connections with homonymous motoneurons, 32% (75/234) with heteronymous motoneurons. However, homonymous and heteronymous motoneurons of similar sizes were equally likely to receive functional connections when located at the same craniocaudal level. Differences in the locations and mean sizes of homonymous and heteronymous motoneurons however, cannot account completely for the observed overall differences in homonymous and heteronymous connectivity.  相似文献   
86.
Thrombotic thrombocytopenic purpura is an acute syndrome with abnormalities in multiple organ systems, which becomes manifest with microangiopathic hemolytic anemia and thrombocytopenia. The hereditary or acquired deficiency of ADAMTS-13 activity leads to an excess of high molecular weight von Willebrand factor multimers in plasma, leading to platelet aggregation and diffuse intravascular thrombus formation, resulting in thrombotic thrombocytopenic purpura. Thrombotic lesions occurring in TTP leads to ischemia and convulsion. Depending on the properties of the bony tissue, fractures are divided into three groups as traumatic, pathological, and stress fractures. A pathologic fracture is a broken bone caused by disease leading to weakness of the bone. This process is most commonly due to osteoporosis, but may also be due to other pathologies such as cancer, infections, inherited bone disorders, or a bone cyst. We herein report a case with a pathologic fracture due to convulsion secondary to thrombotic thrombocytopenic pupura. Thrombotic lesions occurring in TTP may lead to ischemia and convulsion, as in our patient and pathological fractures presented in our case report may occur as a result of severe muscle contractions associated with convulsive activity. Thrombotic thrombocytopenic pupura is a disease that involves many organ systems and thus may have a very wide spectrum of clinical presentations.  相似文献   
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88.
Asprosin associated with insulin resistance is a newly discovered peptide hormone. The peptide promotes hepatic glucose production. Polycystic ovary syndrome (PCOS) is a metabolic disorder. Insulin resistance plays a vital role in the pathogenesis of the disease. The aim of this study was to discover the association between insulin resistance and asprosin in women with PCOS. We recruited 78 subjects with PCOS and 78 age-matched and body mass index (BMI)-matched controls into this cross-sectional study. Circulating asprosin levels were validated using ELISA method. We also determined metabolic and hormonal parameters of the involved subjects. We found that circulating asprosin levels were elevated in women with PCOS with respect to controls. Asprosin levels showed a positive correlation with insulin resistance, BMI, and free androgen index (FAI). Moreover, subjects with the highest tertile of asprosin levels represented increased odds of having PCOS as compared to those subjects with the lowest tertile asprosin levels. Increased asprosin levels resulted to high possibility of having PCOS risk associated with insulin resistance.  相似文献   
89.
90.
The incidence of skeletal muscle metastases is reported to be less than 1% of metastases of haematogenous origin. Distant skeletal muscle metastases from head and neck squamous cell carcinomas are exceedingly rare. Only a case with tongue carcinoma metastasized to paravertebral muscles, has been reported so far. The reasons for the rarity of metastatic involvement of skeletal muscle are still unclear. The presence of skeletal muscle metastases in the setting of disseminated disease offers no hope for curative treatment. We report an unusual case of a 63-year-old patient with tongue carcinoma metastasizing to the left shoulder muscles. To our knowledge, this is the first such case to be reported in the English medical literature.  相似文献   
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