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61.
62.
Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)..  相似文献   
63.
To study the efficacy of a treatment strategy for the management of hypertensive urgencies, the authors evaluated 549 patients admitted to the emergency department. They were first assigned to a 30-minute rest period, then a follow-up blood pressure measurement was carried out. Patients who did not respond to rest were randomly assigned to receive an oral dose of an antihypertensive drug with different mechanisms of action and pharmacodynamic properties (perindopril, amlodipine, or labetalol), and blood pressure was reassessed at 60- and 120-minute intervals. A satisfactory blood pressure response to rest (defined as postintervention systolic blood pressure < 180 mm Hg and diastolic blood pressure < 110 mm Hg, with at least a 20 mm Hg reduction in basal systolic blood pressure and/or a 10-mm Hg reduction in basal diastolic blood pressure) was observed in 31.9% of population. Among nonresponders, 79.1% had a satisfactory blood pressure response to the antihypertensive drug treatment in a 2-hour average follow-up period. No major adverse events were observed. This treatment strategy, based on standardized rest as an initial step and different antihypertensive drugs, can be effective and safe for the management of patients with hypertensive urgencies.  相似文献   
64.
OBJECTIVE: Familial Mediterranean fever (FMF) is a genetically recessive inflammatory disease caused by mutations in the MEFV gene. Most patients of non-Ashkenazi Jewish ancestry or those who are homozygous for M694V manifest a severe disease course, but some express a mild form of the disease. We therefore searched for other genes which could possibly be implicated in the disease phenotype. We tested MICA (major histocompatibility complex class I chain-related gene A) because it has been associated with a number of other inflammatory disorders. METHODS: One hundred fifty FMF probands and their family members were evaluated. The MEFV gene was screened by a combination of denaturing gradient-gel electrophoresis, restriction fragment length polymorphism, and amplification refractory mutation system. The MICA transmembrane polymorphism in exon 5 was analyzed after biotin-labeled polymerase chain reaction products were loaded onto sequencing gels and subjected to autoradiography. RESULTS: The contribution of MICA to the FMF phenotype was confirmed after adjustment for the patient's ancestry and for the MEFV genotype. MEFV was individually the most important prognostic factor for the disease. However, the impact of M694V homozygosity on the age at disease onset (OR 2.3) was aggravated if patients also inherited MICA-A9 (OR 6.3). In contrast, the frequency of attacks was found to be dramatically reduced (OR 0.16) in patients with MICA-A4. CONCLUSION: We have identified the first FMF modifier locus, MICA. FMF is the first model of a Mendelian disease associated with MICA. These results clarify, at least partly, the inconsistent phenotype-MEFV correlation in FMF.  相似文献   
65.
The pump's outflow connector of the Novel Left Ventricular Assist System I (Novel LVAS I) has been redesigned to be sutured to the infrarenal abdominal aorta either as a procedure of choice (due to its simplicity) or as an alternative in the presence of an unhealthy descending thoracic aorta. The implantation of the Novel Left Ventricular Assist System II (Novel LVAS II) requires only a single passage of the pump's inflow connector through the diaphragm. Of still greater importance, the Novel LVAS II enables a considerably shorter (20- or 22-mm) Dacron vascular graft as the outflow connector to the abdominal infrarenal aorta. The electrocardiogram-synchronized Novel LVAS II possibly ensures the most effective approach to the perfusion of visceral organs and kidneys, while avoiding both excessive mechanical stress on the blood and anatomical and functional damage to the native left ventricle.  相似文献   
66.
This study evaluated the safety and efficacy of a sirolimus, corticosteroid, and cyclosporine reduction regimen in an open‐label, 12‐month trial of 420 de novo renal allograft recipients at 49 European transplant centers. One month post‐transplantation, 357 patients were randomized to receive standard‐dose cyclosporine (sCsA, n = 179) or reduced‐dose cyclosporine (rCsA, n = 178). All patients also received sirolimus and corticosteroids. The primary end points were the rate of biopsy‐confirmed acute rejection (BCAR) and renal function, as measured by serum creatinine. Baseline demographic and donor characteristics were similar between groups. BCAR rates at 12 months were not significantly different: 11.2% for rCsA patients and 16.2% for sCsA patients. Mean serum creatinine (±SEM) was significantly lower (1.75 ± 0.10 vs. 1.97 ± 0.07 mg/dl, < 0.001), and creatinine clearance (±SEM; Nankivell method) was significantly higher (57.8 ± 1.78 vs. 49.5 ± 2.46 ml/min, < 0.001) in patients receiving rCsA versus sCsA at 1 year, respectively. Patient and graft survival exceeded 98% in both groups. No significant differences in infection or malignancy were noted between groups. The rCsA with sirolimus and corticosteroid regimen resulted in excellent 12‐month patient and graft survival, a low incidence of BCAR, and improved renal function in renal allograft recipients. Sirolimus administered with rCsA and corticosteroids provided adequate immunosuppression while reducing the potential for the nephrotoxic effects of cyclosporine. These findings may help to improve long‐term renal allograft outcomes.  相似文献   
67.
68.

Objective

The objective of this paper is to show that platysma flaps have good results and should be an alternative in reconstructive surgery for oral tumors when microsurgery is not possible. It is a versatile, portable, and thin flap, is easy to perform, and can be obtained during neck dissection, with a primary closure of the donor site.

Methods

Five cases are presented, three men and two women, 51 and 71 years old, with medium size (2–4 cm) defects of oral cavity after the excision of squamous cell carcinomas. All of them were reconstructed with a platysma flap after neck dissection. This reconstruction technique was chosen because of the poor conditions of these patients to allow a microsurgical reconstruction.

Results

Non-local complications occurred with this technique. Overall aesthetic results were acceptable in all the patients. There were no cases of total necrosis flap, dehiscence, fistula or fibrosis. Only one case of partial necrosis occurred in one end of the flap, which was resolved with excision of necrotic tissue and closure by secondary intention.

Conclusion

The platysma flap is a good method to reconstruct small and medium sized defects of oral cavity, especially in patients where a microsurgery reconstruction is not possible.  相似文献   
69.
70.
Journal of Neuro-Oncology - Intracranial meningiomas rarely present with multiple lesions. To the best of our knowledge, current literature regarding meningiomatosis (MM) is mostly comprised of...  相似文献   
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