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排序方式: 共有9981条查询结果,搜索用时 15 毫秒
961.
Takashi Matsuda Kiyoaki Matsui Yoshikazu Shimakoshi Yoshitomi Aida Shinsuke Hukuda 《Calcified tissue international》1991,49(6):403-406
Summary Bisphosphonates are potent inhibitors of bone resorption. In previous studies, we have shown that ovariectomy accelerated
bone resorption and 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) inhibits ovariectomy-accelerated bone resorption in female
Wistar adult rats. As interleukin 1 (IL-1) stimulates bone resorptionin vitro andin vivo, we have investigated the effects of ovariectomy and HEBP administeredin vivo on IL-1 secretion from peritoneal macrophages in adult rats. Ovariectomy or sham surgery were performed in female Wistar
rats at 40 weeks of age. Overiectomized and sham-operated rats were administered with HEBP (10 mg) or saline, 10 times in
total, from 43 to 46 weeks of age. Paraffin oil-induced peritoneal macrophages at 46 weeks of age were cultured for 24 hours.
Lipopolysaccharide (LPS)-stimulated peritoneal macrophages from ovariectomized rats secreted more IL-1 than sham-operated
rats. HEBP decreased LPS-stimulated IL-1 secretion from peritoneal macrophages in ovariectomized rats, but not in sham-operated
rats.In vivo administration of HEBP decreased IL-1 secretion only in postovariectomy hyperresorptive states. These results suggest that
alterations in LPS-stimulated IL-1 secretion from oil-induced peritoneal macrophages may be responsible, at least in part,
for the postovariectomy acceleration in bone resorption and its inhibition by HEBP. 相似文献
962.
963.
ISABELLA L. KARLE JUDITH L. FLIPPEN-ANDERSON M. SUKUMAR P. BALARAM 《Chemical biology & drug design》1990,35(6):518-526
An apolar helical decapeptide with different end groups, Boc- or Ac-, crystallizes in a completely parallel fashion for the Boc-analog and in an antiparallel fashion for the Ac-analog. In both crystals, the packing motif consists of rows of parallel molecules. In the Boc-crystals, adjacent rows assemble with the helix axes pointed in the same direction. In the Ac-crystals, adjacent rows assemble with the helix axes pointed in opposite directions. The conformations of the molecules in both crystals are quite similar, predominantly α-helical, except for the tryptophanyl side chain where χ1? 60° in the Boc- analog and ? 180° in the Ac-analog. As a result, there is one lateral hydrogen bond between helices, N(lε)…O(7), in the Ac-analog. The structures do not provide a ready rationalization of packing preference in terms of side-chain interactions and do not support a major role for helix dipole interactions in determining helix orientation in crystals. The crystal parameters are as follow. Boc-analog: C3H7,N11O13 C3H7OH, space group P1 with a = 10.250(3) Å, b = 12.451(4) Å, c = 15.077(6) Å, x= 96.55(3)°, β= 92.31(3)°, y= 106.37(3)°, Z = 1, R = 5.5% for 5581 data (|F| > 3.0a(F)), resolution 0.89 Å. Ac-analog: C57,H91,N11,O12, space group P21, with a = 9.965(1) Å, b = 19.707(3) Å, c = 16.648(3) Å, β= 94.08(1), Z = 2, R = 7.2% for 2530 data (|F| > 3.0σ(F)), resolution 1.00 Å. 相似文献
964.
常见谷类和薯类的血糖生成指数 总被引:25,自引:1,他引:24
目的 : 测定我国常见谷类和薯类食物血糖生成指数值 ( Glycemic Index,GI) ,探讨碳水化物种类、加工方法与食物消化吸收和血糖应答的关系。方法 : 根据食物碳水化物的含量计算含有 5 0 g碳水化物的食物量 ,用 5 0 g葡萄糖为对照物。每组 8~ 1 2人测空腹血糖后 ,服用实验物 ,测定 2 h内不同时间的血糖水平。根据 Wolver方法计算食物的 GI值。结果 : 测定了 9个糖类和 62个食物的 GI值。结论 : 相同量的碳水化物的食物有不同的 GI值 ;GI值的高低与食物中碳水化物的利用有关。食物的加工方式和碳水化物的种类对 GI水平有显著影响 相似文献
965.
966.
Purpose: To present and discuss oculometry data in a series of adults with high myopia followed between the ages of 26 and 54 years. Emphasis is on axial length (AL) findings and corneal curvature radius (Crad). Methods: Thirty‐four out of the 39 individuals recruited as teenagers from a Copenhagen 1948 birth cohort with myopia of at least 6 D have had current follow‐up exams, to include AL measurements (by ultrasound, 1974–2002; the latter year also with the Zeiss IOLMaster) and keratometry. The cross‐sectional and longitudinal analyses are based primarily on the eyes with high myopia; however, the fellow eye is also assessed in unilateral cases. Results: At age 54 years, the maximum myopia in the series was ?26 D; the highest AL value was 35.4 mm. The myopia had increased in most, with an increase from the 26‐year oculometry baseline averaging 1.0 D [standard deviation (SD) 1.84]. Ultrasound measurements over the 28 years gave a significant correlation between axial eye elongation and myopia progression of adult age (r = 0.65). The regression line was y = 0.43 + 0.36x, with myopia increase on the x‐axis. Throughout sessions, the association between AL and refraction was given by correlation coefficients numerically above 0.8, whereas AL and Crad had r‐values of 0.3–0.5. However, a mean Crad in the sample of 7.66 (SD 0.28) mm meant that the more general expectancy of rather flat corneas in high myopia was not fulfilled. Our data further suggested a reduction in lens power over the study period. Conclusion: In relation to refraction, AL and Crad remain the two main oculometry parameters. Apparently the correlation patterns regarding the cornea that are broadly valid for axial ametropia in the population cannot be extended to the marginal high myopia tail of the distribution. A significant proportion of eyes with high myopia thus had steeper corneas than expected, as a so‐called index contribution (albeit a small one) to the marginal refractive error. 相似文献
967.
武汉地区成年人腰椎骨密度调查分析 总被引:3,自引:0,他引:3
目的 了解武汉地区成年人腰椎骨密度数据分布特征 ,为诊断骨质疏松症提供正常参考值。方法 应用美国NorlandXR 2 6双能X线骨密度仪对武汉地区 618名成年人的腰椎 (L2~ 4)骨密度进行检测 ,全部数据经SPSS10 .0统计软件处理后生成地区性骨密度分布模型。结果 腰椎骨密度值不论男性和女性 ,均在 30岁左右达峰值 ,以后随年龄增长 ,骨密度值逐渐降低。 5 0岁以前 ,男性与女性的骨密度值差异无统计学意义 (P >0 .0 5 ) ;5 0岁以后 ,男性明显高于女性 ,且在 60~ 65岁期间出现第 2峰 ,随后很快下降。结论 武汉地区成年人腰椎骨密度值分布基本符合亚洲人骨密度分布特征 ,但各年龄段骨密度均值均偏低 ,故该地区骨质疏松症诊断标准必须稍作修改 相似文献
968.
E. A. Gore J. J. Sanders J. P. Pandey Y. Palesch G. M. P. Galbraith 《Journal of clinical periodontology》1998,25(10):781-785
Abstract. Adult periodontitis is a complex multifactorial disease whose etiology is not well defined. The pro-inflammatory and bone resorptive properties of interleukin-1 beta (IL-1β) strongly suggest a role for this cytokine in the pathogenesis of periodontal disease. In the study reported here, the frequency of IL-1β+3953 genotypes including allele 2 of the IL-1β+3953 restriction fragment length bi-allelic polymorphism was significantly increased in patients with advanced adult periodontitis compared to those with early and moderate disease. Furthermore, allele 2 was associated with increased production of IL-1β by activated peripheral blood polymorphonuclear cells of patients with advanced disease, although this increase failed to reach statistical significance. Finally, the data obtained revealed significant linkage disequilibrium between allele 2 of the IL-1β+3953 polymorphism and allele 2 of the bi-allelic IL-1α−889 polymorphism in both patients and orally healthy controls. These findings provide new insight into the possible role of IL-1α and β gene polymorphisms in the susceptibility to adult periodontitis. 相似文献
969.
Guido Collina V. Eusebi Carlo Capella Juan Rosai 《Virchows Archiv : an international journal of pathology》1998,433(4):291-296
Four cases of trichoblastoma rich in Merkel cells (MCs) are reported. They occurred in two men and two women, with ages ranging
from 58 to 76 years (mean 67.5 years). MCs were detected immunohistochemically with antibodies to keratin 20, chromogranin
A and neuron-specific enolase (NSE). In an attempt at better definition of the nature and role of MCs in trichoblastoma, the
distribution of MCs in normal adult and fetal skins obtained at autopsy was studied. In addition, ten cases of sebaceous naevus
of Jadassohn (NSJ) were evaluated along similar lines. MCs made up 2–20% of the tumour cells in trichoblastomas; they were
present in normal fetal skin and were rare in normal adult skin. All but one of the cases of NSJ showed numerous positive
cells in the epidermal component of the lesion with all three antibodies. Six basal cell carcinomas and one syringocystadenoma
papilliferum associated with NSJ were negative with keratin 20, chromogranin A and NSE antibodies, whereas a minute trichoblastoma
arising against the same background was positive for these markers. Hair follicle cell tumours may recapitulate the skin embryogenesis,
as numerous MCs are present in fetal follicles, but only occasional such cells are seen in adult skin.
Received: 26 February 1998 / Accepted: 22 April 1998 相似文献
970.
Ikuya Ooshima Takashi Maruyama Kazunori Ootsuki Masahiko Ozaki 《Journal of Hepato-Biliary-Pancreatic Surgery》1998,5(4):455-458
Preduodenal portal vein (PDPV) is a rare developmental anomaly. We recently encountered this anomaly in a 73-year-old woman
who had gastric cancer and colonic cancer with liver metastasis. The PDPV was diagnosed preoperatively by computed tomography
and angiography. To the best of our knowledge, there are only 19 adult cases reported in the world literature, with this additional
case being reported here. In infants the anomaly has often been associated with duodenal obstruction, but in adults it is
often symptomless. We discuss the disease process, embryology, diagnosis, association with other anomalies, and surgical treatment.
Received for publication on Feb. 24, 1998; accepted on April 7, 1998 相似文献