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101.
Data on the effects of laser radiation on primary teeth are scarce. This study investigates the effects of exposing sound
enamel, photo-initiated sound enamel, sound dentine and carious dentine of extracted primary teeth to a pulsed neodymium-yttrium
aluminium garnet laser (Nd-YAG, wavelength 1.06 μm, pulse length 15μs). Each type of tissue was exposed to three fiuences.
Qualitative and quantitative assessments of the irradiated areas revealed that the most marked changes were produced in carious
dentine, followed in ranking order by sound dentine, photo-initiated enamel and sound enamel. Evidence of thermal damage to
the hard tissues peripheral to the fibre-optic tip, and considerable inter-sample variation were found. The experimental evidence
obtained in this in vitro study does not support the clinical use of pulsed laser at 1.06 μm wavelength for cutting primary
enamel and dentine. 相似文献
102.
M. Kneissel P. Roschger W. Steiner D. Schamall G. Kalchhauser A. Boyde M. Teschler-Nicola 《Calcified tissue international》1997,61(2):95-100
There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous
bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series
of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were
collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret
conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally,
using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis
on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children
consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with
small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present
in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material.
Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately
50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest
that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency
or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations
was probably prevalent.
Received: 1 March 1996 / Accepted: 31 December 1996 相似文献
103.
创伤骨科中责任制护理初探 总被引:1,自引:0,他引:1
本文复习了有关责任制护理的理论,从创伤骨科的角度,介绍了这一护理技术在创伤骨科中具体应用方法。通过对创伤骨科病人心理及临床特点的分析,提出了针对创伤病人的护理问题,订出护理计划,在阐述了责任制护理具体实施的优点时,对现存的问题也进行了分析,提出了改进措施。 相似文献
104.
原发性色素性结节状肾上腺皮质病(附4例报告) 总被引:1,自引:0,他引:1
目的:探讨原发性色素性结节状肾上腺皮质病(PPNAD)的临床表现和诊断治疗方法。方法:总结4例PPNAD的临床资料,4例均有库欣综合征的临床表现,内分泌检查结果提示为功能自主性肾上腺皮质肿瘤,但影像学检查并未发现肾上腺肿瘤。结果:4例患者均行单侧肾上腺全切除术,手术标本均表现为肾上腺大小正常或轻度增大,外表和切面上见黑色或深褐色小结节,结节间皮质萎缩,光镜下见组成结节的细胞体积大,脑质嗜伊红染色、颗粒状,部分细胞脑质中的颗粒状色素颗粒具脂褐质染色特征。结论:PPNAD在青少年中是一种引起库欣综合征的罕见病因,双侧肾上腺切除术是治愈本病的方法。 相似文献
105.
N. Zamberlan R. Castello D. Gatti M. Rossini V. Braga E. Fracassi Prof. S. Adami 《Osteoporosis international》1997,7(2):133-137
Treatment with gonadotropin-releasing hormone (GnRH) agonist leads to enhanced bone turnover and accelerated bone loss in premenopausal women with endometriosis, uterine leiomyomatomas and hirsutism. Sodium etidronate is a powerful inhibitor of bone resorption which has been proven efficacious in the prevention and treatment of postmenopausal osteoporosis. The objective of this study was to evaluate the skeletal effects of 6 months of therapy with the depot preparation of the GnRH agonist triptorelin (decapeptil 3.75 mg intramuscularly every 4 weeks) in 24 hirsute patients, aged 24–33 years, with hyperandrogenic chronic anovulation. Ten patients also received cyclical etidronate in an oral dose of 400 mg/day for 2 weeks, followed by an 11-week period of 500 mg/day elemental oral calcium (one cycle). The remaining 14 patients received 500 mg/day of elemental calcium continuously. After 6 months all treatments were discontinued for at least a further 6 months. Bone mineral density (BMD) at lumbar spine and hip (dual-energy X-ray absorptiometry, Sophos LXRA, France) and biochemical markers (serum alkaline phosphatase, osteocalcin, urinary N-telopeptide and hydroxyproline/creatinine ratio) were evaluated at baseline, 6 months and 12 months. In the group given GnRH agonist alone BMD fell significantly at all measured skeletal sites during the first 6 months. In the patients treated with etidronate a significant decrease in BMD was observed at lumbar spine but not in the femoral neck and trochanter, and the changes at lumbar spine and trochanter were significantly smaller than those in the control group. At 6 months bone turnover was also increased in patients treated with GnRH and calcium. Cyclical etidronate prevented the increase in biochemical markers of bone formation and resorption, with the exception of calcium/creatinine excretion, which was significantly increased in both groups. Six months after treatment withdrawal BMD did not recover in either group. Biochemical markers (N-telopeptide, serum alkaline phosphatase) remained increased in those patients previously treated with calcium alone while they remained close to baseline values in the patients treated with cyclical etidronate.Our study indicates that: (1) GnRH agonist therapy causes remarkable bone loss in young individuals with androgen excess who are expected to have increased bone mass; (2) this bone loss can be partially prevented by intermittent cyclical etidronate therapy. 相似文献
106.
E. Casari M. Alfano M. Valente G. D. Clarke G. Ferni V. Grazioli 《Osteoporosis international》1997,7(6):539-543
The ovariectomized rat is the most commonly used animal model of human postmenopausal osteoporosis, exhibiting a high rate
of bone turnover with resorption exceeding formation. At present, bone turnover is quantified directly by dynamic histomorphometry.
The aim of the present study was to determine whether the measurement of the urinary output of some specific bone collagen
catabolites — pyridinolines and hydroxylysine glycosides — could be used to indirectly monitor the initial phase of bone turnover
increase in ovariectomized 90-day-old rats. Ninety-day-old female rats were randomly divided into three groups (n=6): ovariectomized, sham-operated and non-treated controls. Urine samples (24 h) were collected 6 days before surgery and
twice weekly for the 4 weeks following ovariectomy. Urinary excretion of pyridinoline (PYD), deoxypyridinoline (DPD), glucosyl-galactosyl-hydroxylysine
(GGHYL) and galactosyl-hydroxylysine (GHYL) were measured. As expected, ovariectomy was associated with a significant decrease
in bone mineral density in both the proximal tibial and distal femoral metaphysis. Compared with both sham-operated and control
animals, ovariectomized rats showed significant increases in PYD, GGHYL and GHYL urinary output 8 days after surgery and in
DPD output after 15 days. These changes were maintained throughout the study. The results confirm that measurement of the
urinary excretion of pyridinolines and hydroxylysine glycosides represents a powerful tool for detecting the onset of bone
turnover in ovariectomized 90-day-old rats. 相似文献
107.
急性左半结肠癌梗阻一期切除吻合治疗39例 总被引:1,自引:0,他引:1
魏云志 《天津医科大学学报》2003,9(1):106-107
目的:探讨左半结肠癌致急性肠梗阻的手术处理方法。方法:回顾分析1995-2001年间39例左半结肠癌致肠梗阻一期切除吻合术的外科临床效果。结果:全组39例病人均采用梗阻近端肠管减压灌洗,并留置盲肠造瘘管术后接负压吸引,术后均一期愈合,未出现吻合口漏。随访2例中,1例存活率58%,3年存活率16%,5年存活率8%。结论:严格掌握手术适应症和基本操作,在病情允许时,对左半结肠癌急性肠梗阻行一期切除吻合手术是可行的。 相似文献
108.
目的 研究联合补充大豆异黄酮和钙对去卵巢大鼠骨质疏松的预防作用。方法 将50只3月龄SD雌性大鼠摘除卵巢后按体重随机分成5组:假手术对照组、手术对照组、大豆异黄酮组(40mg/kgBW)、钙组(100mg/kgBW)、钙+大豆异黄酮组(Ca100mg/kgBW+SI40mg/kgBW)。连续灌胃饲养3个月后测定大鼠血清骨钙素,左侧股骨测定骨密度和骨钙含量、右侧股骨进行骨组织形态学计量分析。结果 Ca+SI组血清BGP水平和股骨骨密度均高于其他去卵巢各组(P〈0.05),但低于Sham组(P〈0.05);Ca+SI组大鼠股骨的骨钙含量与Ca组、Sham组差异均无统计学意义;在去卵巢各组大鼠中手术对照组、大豆异黄酮组和钙组大鼠的骨小梁数目和骨小梁厚度显著减少,骨小梁间距明显增宽,与钙+大豆异黄酮组相比有显著差异(P〈0.05)。结论 与单独补充大豆异黄酮或钙相比,大豆异黄酮与钙的联合应用能够更有效地预防去卵巢大鼠骨质疏松的发生。 相似文献
109.
110.
肝移植已成为原发性肝癌治疗的一种重要选择。选择合适的肝癌病例作为移植对象是决定疗效及预后的关键,另外手术禁忌证及术后复发等问题也要慎重考虑。本文就肝癌肝移植治疗方面相关问题近年来的研究情况进行综述。 相似文献