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61.
We used volumetric quantitative computed tomography (QCT) scans to evaluate volumetric bone density (vBMD), geometry, and strength in the thoracic (T8 to T10) and lumbar (L3 to L5) spine and determined how these parameters varied with age, sex, and spinal region. Participants included 690 participants of the Framingham Study, 40 to 87 years old (mean, 61 years). In both women and men, trabecular vBMD declined with age similarly for lumbar and thoracic regions, whereas cortical vBMD and integral vBMD, vertebral strength, and compressive force declined more at the lumbar spine than thoracic spine (interaction, p < 0.01). Notably, in men, cortical vBMD increased (β = 0.0004, p = 0.01), and vertebral strength did not change (β = 1.9305, p = 0.66) at the thoracic spine with age. In both women and men, vertebral cross-sectional area increased less and the factor-of-risk increased more with age at the lumbar than at the thoracic region (interaction, p < 0.01). For example, in women, the factor-of-risk for forward flexion increased (worsened) with age 6.8-fold more in the lumbar spine (β = 0.0157), compared with the thoracic spine (β = 0.0023). vBMD and vertebral strength declined more and the factor-of-risk increased more with age in women than men (interaction, p < 0.01). For instance, integral vBMD for the lumbar spine declined 36% from 40 to 75 years of age in women compared with 18% in men. There was little or no age-related change in the forces applied to the thoracic vertebrae in either women or men. Age-related changes were greater in the lumbar spine than in the thoracic region and greater in women than men. Whereas women lost bone density and strength at both the thoracic and lumbar spine, in men, vertebral strength declined only at the lumbar spine. Our study confirms the importance of evaluating determinants of vertebral strength in both the thoracic and lumbar spine and in both women and men to understand mechanisms underlying the structural failure of vertebral bodies with aging.  相似文献   
62.
Guidelines for osteoporosis treatment are available; however, these guidelines suggest when to treat patients, without specific recommendations on what drugs to prescribe in various situations. Choice of osteoporosis therapy should be individualized based on consideration of the efficacy, safety, cost, convenience (i.e., dosing regimen and delivery), and other non-osteoporosis-related benefits associated with each agent. Bisphosphonates, administered orally or intravenously, should be considered first-line therapy, particularly in older patients, owing to their efficacy across multiple skeletal sites; however, there are potential short- and long-term safety concerns. Selective estrogen receptor modulators should be considered for younger postmenopausal women at greater risk for vertebral than hip fractures or as second-line therapy in women who cannot tolerate first-line therapies. Low-dose hormone therapy may be appropriate as prevention in women with menopausal symptoms at lower fracture risk. Calcitonin, with its relatively benign safety profile, may be appropriate for elderly women who may have difficulty following the complex dosing schedules of oral bisphosphonates. Anabolic therapies such as teriparatide should be considered for high-risk patients. Strontium ranelate (approved outside of North America), with both anabolic and antiresorptive properties, may be appropriate for women who cannot tolerate or are unable to take bisphosphonates. Denosumab is a monoclonal antibody appropriate for women at high fracture risk or who have failed other osteoporosis therapies, and may be considered in patients with renal insufficiency. It will be important to incorporate newer agents (e.g., bazedoxifene, tissue selective estrogen complex) into this individualized treatment paradigm to optimize clinical outcomes in patients with osteoporosis.  相似文献   
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Paratesticular tumors are extremely rare, with paratesticular rhabdomyosarcoma being the most common finding. A 6-month-old boy presented with an asymptomatic, right intrascrotal mass whereby the testicle was surrounded by a friable lipomatous tumor. Frozen section revealed an inflammatory process, negative for malignancy. Tumorectomy with vaginal resection was performed, maintaining the testicle and excretory ducts. Histopathologic findings showed a juvenile xanthogranuloma, a non-Langerhans histiocytosis commonly described in infants in the skin and skeletal muscle. The patient is doing well 2 years after surgery and is the first such case reported in the literature with successful conservative treatment.  相似文献   
66.
Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator.  相似文献   
67.
Objective To construct a eukaryotic expression system with pcDNA3-PfCSP/Hela for the Circ umsporozoite protein (CSP) gene of Plasmodium falciparum (P.falciparum), t o observe the immune responses in BALB/c mice induced by the expressed proteins .Methods The recombinant plasmid pcDNA3-PfCSP was transformed into the Hela cell line. The expressed protein was isolated and analyzed by using SDS-PAGE and used for immunization of BALB/c mice by subcutaneous, intravenous, and intraperitone al adminstration.Enzyme-linked immunosorbent assay(ELISA), Dot-ELISA, Wester n blot, T lymphocyte proliferation test, natural killer cell(NKC) activity assay , and CD4(+) and CD8(+) T cell detection were used for observation of humoral an d cellular immune responses.Results Immune sera strongly reacted with the expressed protein, antibody titer was up to 1∶6400 as detected by ELISA.Western blot analysis revealed a specific b and at 38.3 Kda.When the spleen cells of normal and immunized BALB/c mice we re specifically stimulated with expressed protein, the optical densities were 0 .12±0.03 and 0.34±0.04, respectively.The latter were significantly highe r than the former (P&lt;0.01).We used the MTT colorimetric assay to measure NKC activity of mice spleen.The results showed that the NKC activity of immuni zed BALB/c mice was remarkably higher than that of the controls (P&lt;0.05). CD4(+) and CD8(+) T cells were detected by using monoclonal antibody immunofluor escence methods.The results showed that the percentage of CD4(+) and CD8(+) T cells of immunized group were significantly higher than that of control group ( P&lt;0.05).Conclusions The humoral and cell-mediated immune responses and elevated NKC activity to pr oducts made with a eukaryotic expression system could be specifically detected i n BALB/c mice.These findings indicate that the expressed protein could enhance the immune function in mice.  相似文献   
68.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、…  相似文献   
69.
A prospective, randomized, controlled trial was conducted to compare truncal vagotomy and drainage (TV), selective vagotomy and drainage (SV) and parietal cell vagotomy (PCV) as elective treatment for duodenal ulcer. Between 11 and 15 years after operation, 248 patients were available for study of the recurrent ulceration rate by a life table method, and 197 patients could be studied with regard to postvagotomy symptoms. The recurrent ulcer rates were 28.5% for TV, 37.4% for SV, and 39.3% for PCV. These differences were not statistically significant. The incidence of severe postvagotomy symptoms was as follows: dyspepsia, 18.4% for TV, 20.5% for SV, 8.6% for PCV; dumping, 5.9% for TV, 19.6% for SV, 2.2% for PCV; diarrhea, 9.8% for TV, 11.8% for SV, 4.4% for PCV. The incidence of severe dumping was significantly less frequent among the PCV patients than the SV group. The differences did not reach statistical significance in any of the other groups. There was no significant difference in the Visick gradings among the three groups either before or after treatment of the failures. About two thirds of the patients in each group were finally satisfied with their operation, often after second operations or prolonged medical treatment. It is concluded that none of the three forms of vagotomy can be recommended as the standard operative treatment of duodenal ulceration.  相似文献   
70.
Stricture formation after transurethral prostatectomy was studied in a randomized clinical trial including 185 patients. The patients were allocated to either a 2-day urethral catheter-dilation or internal Otis urethrotomy and to an operation with either a polytetrafluoroethylene coated or an uninsulated metal resectoscope. Urethral stricture was defined as an obstruction resulting in a maximum urine flow rate of less than 15 ml. per second and not permitting the passage of a 21F cystoscope. The frequency of urethral strictures was significantly lower after Otis internal urethrotomy (4 per cent) than after a 2-day urethral catheter dilation (16 per cent). The incidence of stricture formation was similar in patients operated on with a polytetrafluoroethylene coated (8 per cent) and with an uninsulated metal (12 per cent) resectoscope sheath. The incidence of stricture formation was unrelated to age, duration of preoperative and postoperative catheterization, operating time and presence of urinary tract infection.  相似文献   
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