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81.
82.
Buccal bifurcation cyst (BBC) is a rare inflammatory odontogenic cyst that typically occurs at the buccal region of the first or second mandibular molars of children. In the current case, a 9-year-old boy complained of an extraoral soft tissue painful swelling. Intraoral examination revealed a partial eruption of the right permanent mandibular first molar with drainage of purulent material and clinical absence of the left mandibular first molar. Panoramic radiographic and computed tomography showed two well-defined areas surrounding the mandibular first molars consistent with cystic lesions. Surgical enucleations were performed and histopathologic analysis revealed inflammatory cysts. Based on the clinical, microscopic, radiographic, and CT images, the diagnosis of bilateral BBC was established. Patient has been under follow-up for about 1 year showing normal bone repair and eruption of the involved teeth. Although BBC is uncommon, it is important to recognize this entity.  相似文献   
83.
Osteopenia: a bone disorder associated with diabetes mellitus   总被引:6,自引:0,他引:6  
Although osteopenia has been associated with human diabetes mellitus, the pathogenesis of diabetic osteopenia is unclear. In the present study, we evaluated the effect of diabetes on histomorphometry, bone mineral density (BMD)—measured by dual-energy X-ray absorptiometry (DXA)—and biomarkers of bone metabolism in rats up to 120 days after the onset of experimental diabetes. Female Wistar rats with a regular estrous cycle were randomly divided into two groups: control rats (n = 15) and diabetic rats without insulin treatment (n = 25). Diabetes was induced by injection of alloxan and was confirmed by the determination of blood glucose concentration (>250mg/dl). The results revealed an approximate threefold increase of femoral trabecular distance in diabetic rats compared to controls. Conversely, trabecular thickness and bone trabecular volume were reduced twofold and 77%, respectively. BMD in both the metadiaphyseal region and total area of the femur was found to be clearly reduced in diabetic animals, with no significant differences between the groups. Serum alkaline phosphatase (ALP) and tartarate-resistant acid phosphatase (TRAP) activities showed significant six- and twofold increases, respectively, in diabetic rats. There were significant decreases in serum calcium and albumin concentrations in diabetic rats, but no difference was observed in serum magnesium, phosphorus, or creatinine concentrations between the groups. Overall, our findings support the conclusion that the diabetic state is associated with alterations in bone turnover, resulting in the development of osteopenia, which is related to the time of evolution of the disorder.  相似文献   
84.
The aim of this study was to evaluate the influence of laser photobiomodulation in cutaneous healing of rats under a hyperlipidic diet. Forty-eight Wistar Albinus rats, weaned, received standard diet (SD) or hyperlipidic diet (HD) for 20 weeks. The groups were divided into SD rats and HD rats, SD-irradiated rats (LSD), and HD-irradiated rats (LHD). Standard cutaneous wound (1 cm2) was created on the dorsum of each rat. The irradiation started immediately after surgery and every 48 h for 7 or 14 days (λ660 nm, 40 mW, 6 J/cm2, ? 0,04 cm2, CW), when they were killed under deep anesthesia. The specimens were removed, routinely processed, stained with hematoxylin/eosin (H/E), and evaluated by light microscopy. Rats fed with hyperlipidic diet had greater intensity in the inflammatory process and prolonged hyperemia. At day 7, the intensity of inflammation was reduced in LSD and LHD groups when compared to their control groups, SD (p?=?0.002) and HD (p?=?0.02). There was an increase in fibroblast proliferation and collagen deposition, especially in the LHD group. At day 14, the HD group presented more intensive hyperemia than the SD group. It can be concluded that the hyperlipidic diet modified the inflammation pattern in wound healing and that laser light has a positive biomodulative effect on the healing process only in early stages.  相似文献   
85.
86.
BACKGROUND: Prior studies of percutaneous transluminal renal artery angioplasty and stenting (PTRAS) for atherosclerotic renal artery stenosis (RAS) have shown that renal function is improved in about 25%, stabilizes in about 40%, but worsens in about 25% of patients. The factors predicting benefit remain controversial. We tested the hypothesis that the baseline glomerular filtration rate (GFR) predicts the changes in GFR and blood pressure (BP) after PTRAS. METHODS: Treated hypertensive patients with positive renal color-coded duplex Doppler velocimetry and clinical criteria were screened by arteriography. Patients (N = 105) were included if they had an RAS >or=70%, a transluminal pressure gradient >or=30 mm Hg and, they had more than 100 days of follow-up. GFR was calculated from the serum creatinine concentration (SCr). Patients were divided by baseline GFR into subgroups with normal to mildly impaired (N = 52) or moderately to severely impaired (N = 53) initial GFR, according to a GFR >or=50 or <50 mL. min-1 respectively. All received PTRAS. RESULTS: For the entire group, after a mean follow-up period of 371 days, there were significant reductions in systolic and diastolic BP (before, 160 +/- 26/91 +/- 12 vs. after, 145 +/- 20/83 +/- 10 mm Hg, respectively; mean +/- SD; P < 0.0001), and a modest increase in the calculated GFR (before, 54 +/- 26 vs. after, 62 +/- 28 mL. min-1; mean +/- SD; P < 0.007). However, in the subgroup of patients with an initially lower GFR there was a significant increase in the calculated GFR (from 33.3 +/- 10 to 54 +/- 24 mL. min-1; mean +/- SD; P < 0.0001) despite no significant change in BP (161 +/- 27/90 +/- 12 vs. 151 +/- 21/86 +/- 12; P = NS). In contrast, in the subgroup with an initially higher GFR, there were significant (P < 0.0001) reductions in systolic BP (from 159 +/- 25 to 138 +/- 16 mm Hg) and diastolic BP (from 91 +/- 11 to 81 +/- 9 mm Hg), but no significant change in the calculated GFR (from 75 +/- 21 to 70.2 +/- 30 mL. min-1; P = NS). The significance of GFR variation in subgroups remained after correction of baseline data to exclude the influence of the expected regression to the mean. CONCLUSIONS: Patients with atherosclerotic RAS fulfilling strict criteria of severity may have significant improvements in BP one year after PTRAS but only modest in GFR. The initial GFR may anticipate whether the benefits in the outcome will be in renal function enhancement (those with an initially depressed GFR) or in hypertension control (those with an initially normal or mildly impaired GFR).  相似文献   
87.
Current data demonstrate pediatric patients who remain on hemodialysis (HD) therapy are more likely to be dialyzed via central venous catheters (CVCs) than arteriovenous grafts (AVGs) and fistulae (AVFs). We retrospectively compared complications and health-related quality of life (HRQOL) associated with different vascular access types at two large centers over a 1-year period. Patients included in the study were younger than 25 years of age, weighed >20 kg, and had received HD for at least 3 months. Thirty CVC patients and 21 AVG/AVF patients received a total of 2,393 and 3,506 HD treatments, respectively. The infectious complication rate was higher for CVC patients, who were hospitalized 3.7 days for each 100 HD treatments versus 0.2 days for AVG/AVF patients (p < 0.01). CVC patients also had a much higher rate of access revision, needing 2.7 hospital days every 100 HD treatments compared with 0.2 days for AVG/AVF patients (p < 0.01). HRQOL scores did not differ between groups. Thus, despite similar HRQOL, CVCs were associated with more complications and greater morbidity when compared with AVG/AVFs. These findings further emphasize the need to use AVG/AVFs as primary HD access for pediatric patients expected to receive a long course of maintenance HD.  相似文献   
88.
Women who require or desire mastectomy for breast cancer one option should be immediate breast reconstruction. Skin-sparing mastectomy (SSM) describes the surgery that maximises breast skin and infra- mammary fold preservation, significantly improves the symmetry and natural appearance and a more satisfied patient. In multiple studies, SSM seems to be oncologically safe in patients undergoing mastectomy for invasive T1-T2 tumours, multicentric tumours, ductal carcinoma in situ or risk-reduction. However, the technique should be avoided in patients with inflammatory breast cancer or in those with extensive tumour involvement of the skin. SSM with nipple areola complex preservation appears to be oncologically safe, providing that the tumour is not close to the nipple and the retro-areolar tissue is free of tumour. Though adjuvant radiotherapy is not an absolute contraindication to SSM, it should be used with caution since it decreases the final cosmetic result.  相似文献   
89.
90.
We analyze the reasons why the use of confidence intervals is highly advisable. Among these reasons, confidence intervals provide an approach to knowledge of the real importance of a result, independently of statistical significance, as well as equivalence assessment between two variables.  相似文献   
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