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91.
目的探讨睾丸微小结石症的超声表现特点及临床意义。方法应用二维超声观察睾丸微小结石症的声像图表现特点并利用彩色多普勒检测内部血流信号进行描述。结果睾丸微小结石症特征性的二维图像表现为斑点数量由睾丸白膜向纵隔、由密集到稀疏的分布特点;图像放大后的斑点多呈短棒状改变;彩色多普勒显示,睾丸内血流信号正常。结论二维超声和彩色多普勒血流显像是诊断睾丸微小结石症的首选影像学诊断方法。睾丸微小结石症可能对生育产生影响。 相似文献
92.
The prevalence of calcified cysts and the significance of calcification as a sign of cyst inactivity in cystic echinococcosis (CE) was evaluated. Seventy-eight patients (36 females, 42 males, mean age 40.8 +/- 16.9 years) with CE, having a total of 137 abdominal cysts (116 hepatic, three splenic, one renal and 17 peritoneal cysts), were diagnosed and followed-up by ultrasound during and after albendazole treatment or as part of the watch-and-wait approach recording changes in the cyst wall and content. In 48 patients with 94 cysts, computed tomography (CT) imaging was additionally available and was correlated with ultrasound findings. Cyst wall calcification was classified into (1) "sprinkled", (2) "eggshell-like", and (3) "circular". Calcification of the cyst wall and/or cyst content was detected in 67 echinococcal cysts (48.9% of all cysts) in 39 patients (15 females, 24 males, mean age 40.8 +/- 14.8 years). Of the total of 67 calcified cysts, only 23 were compatible with WHO type CE5, 18 with WHO type CE4. Judged by cyst content, the remaining 26 were of WHO type CE1, CE2 and CE3 (n = 1, n = 8, and n = 17, respectively). During a mean period of 34.3 months (+/- 21.3 months) the majority of cysts (n = 32) did not exhibit any change in cyst content and wall properties. Fourteen cysts showed signs of progressive involution, five cysts (all of WHO type CE3) of renewed activity defined by recurring fluid collection. In 16 cysts, no follow-up was available due to surgery or drop out. Calcification of the cyst is not restricted to the inactive WHO cyst types CE4 and CE5, but occurs in all stages and in up to 50% of cysts. The completeness and, most importantly, the stability of consolidation of cyst content over time predicts cyst inactivity more reliably. 相似文献
93.
Abstract: This article aims at investigating in vivo evaluation of lyophilization procedure on the biocompatibility of bovine pericardium treated with glutaraldehyde (GA). The bovine pericardium was fixed with 0.5% glutaraldehyde during 10 days and preserved in 4% formaldehyde (FA). Two groups of samples were prepared from treated membranes: Group 1, nonlyophilized samples and Group 2, lyophilized samples. Male Sprague-Dawley rats (4 weeks after birth) were anesthetized (pentobarbital sodium 25 mg/kg of body weight) and in each one were implanted subcutaneously in the dorsal region a sample from Group 1 and another from Group 2. These samples were explanted after 30 days for histological analysis. No intercurrences took place after the surgery. No differences ( P > 0.05) in the calcification, granulomatous reaction, mononuclear infiltration, and granulation tissue development was observed between both groups. The implanted lyophilized samples presented a trend for a reduced inflammatory reaction. Lyophilization of the bovine pericardium does not seem to increase the above listed tissue reaction. 相似文献
94.
95.
Scanning electron microscopy and electron probe microanalysis studies are reported on thin sections of calcified coacervates
of α-elastin. It is found that the capacity of elastin coacervates to initiate calcification is a bulk property of the coacervate
and not limited to the serum-coacervate interface, that the calcium phosphate deposits act to bind the protein units together
and slow the dissolution and spreading of the coacervate as it floats on an air-water interface, and that, within the limits
of detectability, there is no involvement of sulfur. As the charged groups of α-elastin had been blocked, the initiation of
deposition is due to neutral sites in the protein which are tightly bound to the calcium phosphate deposits. 相似文献
96.
An electron microscope study was made of the formation and structure of the inner ligament ofMytilus edulis andPinctada radiata. This part of the ligament is derived from the isthmus cells which are irregular columnar in shape. They exhibit a prominent rough endoplasmic reticulum and a Golgi apparatus, which are concerned with the elaboration of vesicles and granules eventually incorporated into an integral part of the conchiolin.The crystals arise at the calcification front at the inner surface of the ligament and are enclosed in envelopes. They consist of long, needle-shaped, single aragonite crystals widely dispersed in the ligament.Although the components of the shell and ligament are similar, differences between them consist of an increased amount of conchiolin, as well as a decrease in the amount, diversity of form, arrangement and growth of the crystals; all probably related to the specialized function of the ligament.This investigation was supported (in part) by grant DE-01825, N.I.D.R., U.S.P.H. Service. 相似文献
97.
In adult human bone, fluoride uptake is accompanied by an increase in apatite crystal size. This increase, however, is not
isotropic but is restricted primarily to growth in width and/or thickness, with no measurable change in length. In the present
study, seeded growth experiments were conducted in vitro to determine whether this anisotropic effect is physicochemical in origin, i.e., a direct result of F- selectively enhancing lateral crystal growth, or is an indirect consequence of F--induced alterations in cellular function and matrix development. The growth reactions were maintained at 37°C under physiologic-like
solution conditions (1.33 mmol/liter Ca2+, 1.0 mmol/liter total phosphate, 0 or 26 mmol/liter carbonate, 270 mmol/kg osmolality, pH 7.4) using constant-composition
methods. When new accretions accumulated to three times the initial seed mass, the solids were collected and net crystal growth
was assessed by X-ray diffraction line broadening analysis. The X-ray results revealed that the carbonate constituent in our
physiologic-like solutions promoted the proliferation of new crystals at the expense of further growth of the seed apatite.
Solution F- concentrations of ∼2 μmol/liter partially offset the repressive effect that carbonate had on primary crystal growth. Moreover,
F- stimulated seed crystal growth in the same anisotropic manner as had been observed for adult human bone apatite, a finding
that suggests that the latter growth in vivo was the consequence, in part, of direct F--mineral interactions.
Received: 14 May 1997 / Accepted: 23 January 1998 相似文献
98.
本文对40例50及50岁以上中老年人伴有心脏瓣膜钙化的病人做骨密度检查,结果显示瓣膜钙化(心脏退行性变)的病人骨密度低于正常对照组又高于BMD减低组,提示心脏退行性变病人的BMD与正常BMD呈负相关而与骨密度减低组病人呈显著正相关。简要讨论骨质疏松、软组织钙化、骨质增生之间可能的内在联系。 相似文献
99.
100.
F. López-Barea E. Burgos J. L. Rodríguez-Peralto J. González-López 《Virchows Archiv : an international journal of pathology》1994,425(2):217-220
This report illustrates a calcified leiomyoma of deep soft tissue in the left leg of a 6-year-old boy. The tumour was composed of spindle cells arranged in interlacing bundles, between which were multiple small and large areas of calcification. Tumour cells were positive for vimentin, desmin and smooth muscle actin. Ultrastructurally, the cells showed numerous pinocytotic vesicles and bundles of intracytoplasmic filaments with smooth muscle dense bodies. Only four calcified leiomyomas have been previously reported in the deep soft tissues of limbs. Here we report a new case and suggest a new pathogenetic scheme involving alkaline phosphatase in the origin of these calcifications. 相似文献