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91.
J. Thiele T. K. Zirbes J. Lorenzen H. M. Kvasnicka S. Scholz A. Erdmann U. Flucke V. Diehl R. Fischer 《Annals of hematology》1997,75(1-2):33-39
In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed
cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition
to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly
(PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML).
Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal
antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index
was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed
the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and
PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid
or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the
control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant
expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant
feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the
latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive
lesions extends previous experimental data on hematopoietic cell kinetics.
Received: 10 March 1997 / Accepted: 18 May 1997 相似文献
92.
本实验以铁骨晶(多肽钙),进口脱脂奶粉,活性钙冲剂,贝壳钙为钙源添加于大鼠正常饲料中。观察结果表明:上述4组钙的吸收率分别为64.4%,69.1%,59.9%,51.6%;钙的储留率分别为89.8%,93.3%,85.2%,79.0%;钙的存留率分别为43.6%,49.0%,32.4%,26.8%;股骨指数分别为7.02×10(-3),6.43×10(-3),6.84×10(-3)。6.88×10(-3);折断力(牛顿)分别为60.54±12.55,46.81±9.32,43.26±16.62,38.24±10.79。同时以铁骨晶为钙源对70例(5~6岁)儿童进行了血清Ca,Fe,Zn,Hb及生长发育的检测。铁骨晶组的身高,体重,胸围分别比对照组增加。铁骨晶组血清Ca,Fe,Zn,Hb也均有较好的改善。这表明铁骨晶具有较好的促进钙吸收利用作用,同时能增加骨强度作用。 相似文献
93.
Bone mineral density in patients with prostatic cancer treated with orchidectomy and with estrogens 总被引:7,自引:0,他引:7
Bone mineral density (BMD) and bone mineral content (BMC) were measured in the femoral neck area, trochanteric area and Wards triangle, and in the distal radius of the left forearm before and after 1 year of endocrine treatment in 27 patients with prostatic cancer. Eleven of the patients were treated with orchidectomy and 16 with combined oral and intramuscular estrogens. The patients were free from metastases during the entire observation period. In the orchidectomized patients, BMD and BMC of the distal radius decreased significantly following treatment, whereas no changes were observed in the estrogen-treated patients. These preliminary results demonstrate that estrogens may protect bone in male subjects also and may merit further investigations on larger groups of patients. 相似文献
94.
95.
以往以乳头为圆心的同心圆剥离法常形成假体的移位,使假体的体表轮廓与前方的自然乳房分离,产生“双重乳房”现象。在研究了女性不同体位下不同的乳房形态及总结了以前的经验后,提出了偏心圆剥离的概念。偏心圆手术设计方法:以乳头为圆心,按其内侧、下侧为直径3/5的比例,以外侧、上侧为直径2/5的比例,形成一偏心圆的剥离范围。偏心圆的直径因考虑到假体的不同形态、大小及底面直径,以经中心假体纵截面的周长的1/2再放大2cm,作为剥离范围的直径。自1991年10月以来已应用了176例,无一术后移位现象,也没有固较多地剥离胸大肌内、下侧止点纤维而影响上肢活动。自然乳房并不是静态的圆锥形或半球形,它具有伸缩的组织学特点,又有随体位变动而变化的特点。用偏心圆法剥离,可使置入的假体与前方的自然乳房融为一体,消除“双重乳房”现象,而成为“真实”的乳房。同时也应积极寻找一种与身体组织相容性好的,弹性、比重与女性乳腺较为一致的,假体容量相对恒定的生物性材料。这样隆乳术才可以更广泛地开展。 相似文献
96.
Hiroshi Uno Yoshihiro Izawa Kiyoshi Sagara Tamotsu Koyama Tokutaro Makita Chia-Yuan Hsu-Chang Mitsugi Sugiyama 《Journal of bone and mineral metabolism》1990,8(1):10-16
The effect of 1α-hydroxyvitamin D3 (1α(OH)D3) on the metabolic bone disorders developed in gastrectomized rats were investigated biochemically and histomorphologically.
1α(OH)D3 was suspended in 0.2 % Triton-X-100 aqueous solution after dissolving in a very small amount of ethanol, was given orally
to the rats for 10 weeks. The sham operated animals and the gastrectomy control animals received the vehicle alone. Gastrectomy
was followed by the development of the metabolic bone disorders after 10 weeks of observation. This was characterized by reduction
in ash content of the femur and histologically by a disappearance of the trabecular bone in tibial metaphysis. Decrease Ca
absorption from the intestines was demonstrated by a radiotracer technique. Biochemical studies showed significant decreases
in serum 25(OH)D concentration in gastrectomized rats. These findings suggest that gastrectomy partially impairs intestinal
absorption of calcium and results in a negative calcium balance, which may contribute to the development of bone metabolic
disorders in rats. The administration of 1α(OH)D3 increased dose-dependently serum calcium and Ca absorption from the intestine and prevented the development of bone metabolic
disorders histomorphologically. 相似文献
97.
C. Schwartz A. Raye R. Petit 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》1997,7(2):115-118
Summary 51 cases of repeat hip replacement have been reviewed, using allografts for acetabular bone loss, stages 2 and 3 (27 lyophilised and 24 deep-frozen). Mean follow-up was 4 years. Loosening was the reason for intervention; 14% of cases were septic. Massive grafts were used in 75% of cases and smaller grafts in 25% of cases. In addition a reinforcement ring was necessary in 75% of cases. Merle d'Aubigné's rating scale was used to assess results. The radiologic assessment score was that of Gross and De Lee.There was no difference between lyophilised and deep-frozen grafts. Clinical scores found 55% of excellent results; 11% were poor, the rest were good or fair. Stability was more troublesome than pain. Radiologic screening showed union between graft and host in 53% of cases but in 41% there was incomplete fusion. In the non-weight-bearing area bone lysis appeared in 14 cases out of 20. Five cases were complete failures; four of these were infected and were reoperated, the bone-graft acting as a foreign body.To date, we have no better bone replacement material than allografts. Fixation of the graft must be secure. An infected hip is not a good indication for this type of operation. Clinical results are satisfactory in more than 80% of cases, although 40% of grafts seem to be incompletely integrated. 相似文献
98.
Agents for prevention or treatment of osteoporosis must now be tested in a large animal species that exhibits bone remodeling.
Ovariectomized, nonhuman primates provide one such model, and they consistently develop osteopenia accompanied by high bone
turnover rates. The goal of this study was to further characterize this model, and particularly to determine the effect of
ovariectomy on bone strength in vertebrae and femoral necks. Longitudinal evaluations of spinal bone mass and serum markers
of bone turnover were performed in 19 sham-ovariectomized (SHAM) and 18 ovariectomized (OVX), domestically reared cynomolgus
monkeys, aged >9 years. OVX monkeys lost bone relative to both baseline values and SHAM controls. Serum markers of bone turnover
were increased by OVX. After 72 weeks, both vertebral bone compressive strength and femoral neck breaking strength were significantly
decreased in OVX animals compared with SHAM. Ovariectomized cynomolgus monkeys, like postmenopausal women, develop accelerated
bone loss, increased bone turnover, and reduced bone strength, and provide a suitable large animal model for efficacy studies
with agents for prevention or treatment of osteoporosis.
Received: 24 June 1996 / Accepted: 3 September 1996 相似文献
99.
I. Gorai Y. Taguchi O. Chaki M. Nakayama H. Minaguchi 《Calcified tissue international》1997,60(4):317-322
Urinary excretion of cross-linked N-telopeptide of type I collagen (NTx) has been reported to be a specific marker of bone
resorption [18]. We assessed a new immunoassay for NTx as an indicator of changes in bone resorption caused by spontaneous
menopause and compared cross-sectionally the levels of urinary NTx, hydroxylysylpyridinoline (HP), lysylpyridinoline (LP),
hydroxyproline (OH-Pr), other serum biochemical indices, and lumbar spine and proximal femur bone mineral density (BMD). Eighty-one
Japanese women aged 22–77 participated in this study; 36 were premenopausal and 45 were postmenopausal. Urinary HP, LP, and
NTx stayed at low levels in the premenopausal period and rose 21%, 30%, and 67% in the postmenopausal period, respectively.
The rise in LP and NTx was statistically significant (P < 0.01), suggesting that NTx is mostly released from bone matrix when bone resorption is accelerated. When premenopausal
women were divided into two age groups and postmenopausal women were divided into two groups according to years since menopause
(YSM) there were significant differences in LP and NTx between women <4 YSM and women aged <40 and those women aged 41+ (P < 0.01 and P < 0.05, respectively). A significant 110% increase in urinary NTx and a 48% increase in urinary LP were observed in postmenopausal
women compared with age-matched premenopausal women aged 45–55. All biochemical markers other than serum PTH correlated significantly
with each other (r = 0.243–0.858, P < 0.05–0.0001). Urinary NTx inversely correlated with lumbar spine BMD. When postmenopausal women were divided into three
groups, the correlation between bone resorption and formation markers in women 0-1 YSM was greater than in women 2–10 YSM
and in women 11 + YSM, indicating that resorption and formation are coupled at the early postmenopausal period. We conclude
that urinary NTx is responsive to changes in bone metabolism caused by estrogen deficiency and may be a more sensitive and
specific marker than HP, LP, or OH-Pr in the early postmenopausal years.
Received: 15 February 1995 / Accepted: 18 October 1996 相似文献
100.
骨与关节肿瘤和瘤样病变1084例统计分析 总被引:5,自引:0,他引:5
目的:分析青海高原地区骨与关节肿瘤及瘤样病变的发病情况。方法:对1963~1995年10月的1084例骨与关节肿瘤及瘤样病变进行了统计分析。结果:良性骨肿瘤722例(66.61%),恶性骨与关节肿瘤249例(22.97%),瘤样病变113例(10.42%),良、恶性肿瘤之比为2.9∶1,男女之比为1.22∶1,好发年龄为11~30岁,好发部位为胫骨(27.3%),其次为股骨(21.8%)。良性骨肿瘤以骨软骨瘤(54.43%)、软骨瘤(21.19%)、骨巨细胞瘤(9.97%)多见。原发恶性骨肿瘤以骨肉瘤(33.3%)、软骨肉瘤(10.85%)、骨髓瘤(10.05%)多见。瘤样病变则以孤立性骨囊肿(46.01%)和骨纤维结构不良(30.97%)多见。结论:本组结果与国内文献对比有许多相似之处,但良性骨肿瘤与恶性骨肿瘤之比与国内文献有较大不同,可能与高原环境有关。 相似文献