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21.
PURPOSE: To study changes in structure and barrier function of the corneal epithelium after penetrating keratoplasty. METHODS: Sixty-nine eyes of 56 patients undergoing penetrating keratoplasty were studied. Fifty-six age-matched normal eyes served as controls. Corneal epithelial structure was studied by using specular microscopy. Barrier function of the corneal epithelium was examined by slit-lamp fluorophotometry. Vital staining, tear function, and corneal sensitivity also were examined. RESULTS: Fluorescein and rose bengal staining scores, incidence of elongated cells, the mean epithelial area, and mean fluorescein uptake were significantly increased in postkeratoplasty eyes compared with controls. Original disease influenced the results of barrier function, where keratoconus revealed better function than bullous keratopathy or corneal scar. However, no such differences were noted in epithelial structure. Six eyes with absence of palisades of Vogt had revealed significantly increased epithelial area and fluorescein uptake. Removal of the running suture caused a decrease in elongated cells and epithelial cell area without significant changes in barrier function. CONCLUSION: Corneal epithelial structure was significantly impaired in postkeratoplasty eyes. Epithelial barrier function of postkeratoplasty eyes was influenced by original diseases. Removal of sutures improves epithelial structure but not barrier function. 相似文献
22.
白细胞介素6在狼疮性肾炎患者小管间质的表达及其意义 总被引:12,自引:0,他引:12
探讨白细胞介素6(IL-6)在狼疮性小管间质病变中的作用。方法 采用ELISA方法与原位分子杂交技术(后者结合IBAS计算机图像分析系统),分别检测42例活动期狼疮性肾炎(LN)患者尿IL-6浓度与其中的15例肾小管间质IL-6mRNA水平。结果 42例活动期LN患者有36例尿IL-6>5pg/mg·cr,其增高程度与尿β_2-m及NAG活性水平呈显著正相关;其中15例肾组织切片中,肾小管间质均有IL-6mRNA表达,并且小管间质病变愈严重,其表达量愈高,而健康肾组织小管间质几无IL-6mRNA表达。结论 LN患者活动期尿IL-6浓度异常增高与肾小管间质IL-6mRNA异常表达有关,提示IL-6在狼疮性小管间质损害过程中可能具有重要作用。 相似文献
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25.
Naruhiro Ishida Noriko Odani‐Kawabata Atsushi Shimazaki Hideaki Hara 《Cardiovascular therapeutics》2006,24(1):1-10
Elevated intraocular pressure (IOP) is one of the most important risk factors for the development of glaucoma, which is a progressive optic neuropathy. Lowering IOP is currently the only therapeutic approach to the therapy of glaucoma. Since the use of pilocarpine eye drops for glaucoma treatment was reported in the late 1870s, academic researchers and pharmaceutical companies attempted to discover new drugs with more potent, prolonged, and safer IOP‐reducing effects. These persistent efforts finally paid off, and prostanoids with FP‐receptor agonist activity were found to be very potent IOP‐lowering agents. To date, three prostanoids (latanoprost, travoprost and bimatoprost) have been launched in many countries, and now a new FP‐receptor agonist, tafluprost, is entering clinical development. All of these prostanoids are superior to the β‐adrenoceptor antagonists in their IOP‐lowering efficacy, and no severe side effects have been reported in their long‐term clinical use. In addition, tafluprost may be expected to improve ocular blood flow. Hence, prostanoids currently occupy center stage among glaucoma medications. It cannot be denied that in terms of efficacy, safety, patient compliance, and medical economy prostanoids are currently the first‐line medicines among ocular antihypertensive drugs. 相似文献
26.
New Xenograft Model of Multiple Myeloma and Efficacy of a Humanized Antibody Against Human Interleukin-6 Receptor 总被引:2,自引:2,他引:2
27.
Y Shimazaki Y Kawashima M Ogawa H Hirose K Miyamoto S Morimoto 《Japanese circulation journal》1985,49(7):679-684
With use of biplane cine-angiocardiograms, the measurements of right and left ventricular volume were determined in 11 children with transposition of the great arteries following Mustard's procedure. Right ventricular end-diastolic volume (RVEDV) ranged from 124 to 264 percent of the normal right ventricular volume with an average of 188 +/- 40 (SDM) percent, and left ventricular end-diastolic volume (LVEDV) ranged from 57 to 181 (122 +/- 43) percent of the normal (p less than 0.01, vs. RVEDV). Right ventricular ejection fraction (RVEF) ranged from 0.26 to 0.66 (0.42 +/- 0.11), and left ventricular ejection fraction (LVEF) ranged from 0.51 to 0.79 (0.66 +/- 0.09) (p less than 0.001, vs RVEF). Left ventriculography showed a deviation of the interventricular septum toward the left ventricle in patients with simple transposition of the great arteries not associated with left ventricular hypertension. The left to right ventricular systolic pressure ratio ranged from 0.22 to 1.02 (0.48 +/- 0.28), and the left to right ventricular end-diastolic volume ratio ranged from 0.43 to 1.00 (0.63 +/- 0.18). There was a high correlation between the left to right ventricular systolic pressure ratio and the left to right ventricular end-diastolic volume ration (r = 0.94, p less than 0.001). The left to right ventricular systolic pressure ratio also correlated well with the right ventricular ejection fraction (r = 0.90, p less than 0.001). Deviation of the interventricular septum was considered to result in a diminished ejection fraction of the right ventricle, in patients with simple transposition of the great arteries not associated with left ventricular hypertension, after Mustard's procedure. 相似文献
28.
This research presents the first example of the formation of a triplex via hydrogen bonding of a synthetic cyanuryl nucleoside (Cn) composed of a 6-membered ring compound (triazine-2,4,6-trione) which functions as a pyrimidine base. The Cn was able to form the triad via hydrogen bonding in two directions with two adenines, one in the antisense and one in the parallel chain. The thermal stability of the duplex between the antisense and sense chains was evaluated via its UV melting temperature. The melting curves of triplexes possessing the cyanuryl nucleoside (sense chain) and two adenines (antisense and parallel chains) were biphasic. To prove the formation of hydrogen bonding between the cyanuryl nucleoside and the adenine base toward the major groove, structural analysis via NMR was undertaken. A cyanuryl nucleoside containing three 15N in triazine-2,4,6-trione was synthesized first, and then the 15N cyanuryl nucleoside was incorporated into target sequences. The triplex containing the A·Cn A triad was analyzed via1H NMR, coupled and decoupled with 15N. This triad has two imino proton signals derived from the cyanuryl nucleoside, split according to the 15N coupling condition, at low field. These results are evidence of the formation of hydrogen bonds between the Cn and adenosine. The solution structure of the triplex was analyzed via NOE information from the imino proton. The cyanuryl nucleoside-containing triplex forms a right-handed helical structure similar to natural triplex DNA, albeit DNA having an enhanced pyrimidine analog in the sense chain capable of bidirectional hydrogen bonding with high sequence selectivity.The triplex formation ability of a sense chain containing a cyanuryl nucleoside was evaluated and the tertiary structure of the triplex was calculated using the NOE in 1H NMR by incorporating a 15N into the base moiety. 相似文献
29.
Takashi Sugawara Masaru Aoyagi Youji Tanaka Masashi Tamaki Daisuke Kobayashi Kikuo Ohno 《Neurosurgical review》2013,36(3):395-402
The diagnosis and treatment of pituitary macroadenomas with entire hematoma fluid accumulation are problematic. Such lesions are often difficult to completely resect, and recurrence is not uncommon. We present five cases of pituitary macroadenomas entirely composed of hematoma fluid and investigated their histopathology to clarify the mechanism of the hematoma fluid accumulation. Five patients with pituitary adenoma and significant intra-tumor hematoma underwent transsphenoidal resection and were retrospectively reviewed for their clinical status, findings on magnetic resonance imaging (MRI), intraoperative findings, and histopathology. The specific surgical techniques used to address these cases were also reviewed. All patients were diagnosed with nonfunctioning pituitary adenomas by histopathological examination. MRI showed all tumors extended to the cavernous sinus. Histopathology showed tumor tissues were located between the thick granulation tissue and the pseudocapsule of the tumor. The thick granulation tissues were composed of collagenous layers, neovascular vessels, and necrotic red blood cells, indicating repeat hemorrhage from the granulation tissues. The boundary between adenoma and normal pituitary gland was identified during surgical removal in four patients and was not identified in the other patient who showed a recurrence 2 years later. Clinical and histopathological findings indicate hematoma fluid accumulation in the present cases is caused by repeat hemorrhage from the reactive granulation tissues and can be regarded as a chronic encapsulated expanding hematoma. In these cases, the boundary between adenoma and normal pituitary gland should be identified before puncturing the hematoma fluid to minimize the risk of tumor recurrence. 相似文献
30.
Recent studies have noted specific expression of hepatocyte nuclear factor (HNF) 1beta in ovarian clear-cell adenocarcinoma (CCA). In this study, we aimed to determine whether HNF-1beta can be a specific marker of CCA in both the ovary and the endometrium and to assess the pathological significance of HNF-1beta expression in CCAs. We examined HNF-1beta expression immunohistochemically in 186 ovarian carcinomas, including 40 CCAs; 33 endometrial carcinomas, including 5 CCAs; 22 endometria at different stages of the menstrual cycle (5 in the proliferative, 12 in the secretory, and 5 in the menstrual phases); and 7 gestational endometria. The incidence of HNF-1beta immunoreactivity differed significantly between CCAs and other histology in both the ovary (100% in the former versus 2% in the latter) and the endometrium (100% in the former versus 0% in the latter) (P < .0001 each). In nonneoplastic endometrium, 25% or more immunoreactive cells were confined to the mid-to-late secretory phase of the menstrual cycle and gestational endometrium. HNF-1beta would be an excellent marker for distinguishing CCAs from other lesions in both the ovary and the endometrium. HNF-1beta expression seems to be associated with physiopathological cytoplasmic glycogen accumulation in these organs. 相似文献