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31.
全眼球冷冻保存角膜的板层角膜移植   总被引:1,自引:0,他引:1  
全眼球液氮冷冻保存法是一种长期保存角膜材料的方法,在板层角膜移植中可收到与新鲜角膜相仿的临床效果。取全眼球液氮冷冻保存的角膜为35例角膜病变患者实施了板层角膜移植术,术后随访1~3年,角膜透明率(包括半透明率)97%,34眼术后视力均有不同程度提高。同时介绍了全眼球液氮冷冻保存方法的操作技术  相似文献   
32.
Introduction: The correction of low to moderate astigmatism is possible today by means of photoablation (PRK), while the treatment of moderate and higher astigmatism still involves refractive keratotomy. Experience has shown that cataract surgery, using modern tunnel techniques with self-healing incisions, results in earlier stability in both the refractive outcome and wound healing. In this study, we attempted to combine the advantages of lamellar keratotomy with those of a pair-wise T-incision as arcuate lamellar keratotomy (ALK). Patients and methods: The clinical outcome of 41 patients who underwent ALK was investigate in a prospective study over a period of 3 years. The pre- and postoperative investigations undertaken included the measurement of astigmatism using a Zeiss keratometer, uncorrected visual acuity, and corrected glare vision using a Humphrey autorefractor. All patients had astigmatism between 2.0 and 7.0 D. Together with a uniform arcuate incision, we used 7 mm (n = 26) and 8 mm (n = 15) mm zones for correction. Results: The average preoperative astigmatism was 4.01 ± 1.90 (median, 3.50) D. After a 3-year follow-up the average postoperative astigmatism was 1.59 ± 1.29 (median, 1.38) D. The astigmatic change induced (Jaffé) after 3 years was about 3.23 ± 2.23 (median, 3.16) D. The average uncorrected visual acuity (log MAR) before ALK was 0.20 ± 0.12 (median, 0.22) and after follow-up, 0.41 ± 0.14 (median, 0.39). Corrected glare vision before surgery was 0.23 ± 0.19 (median, 0.10) and afterwards, 0.25 ± 0.22 (median, 0.14). Conclusions: Arcuate lamellar keratomy (ALK) stood the test as a routine clinical procedure for correction of moderate astigmatism with stable postoperative functional outcomes. We did not find impairment of glare vision following this procedure.   相似文献   
33.
In an earlier report, a modification of the Attwood's stain was used to study sections of decalcified bone and the procedure aided in the distinction between lamellar and woven bone. Lamellar bone showed preferential affinity for phloxine (red) yet resisted differentiation with tartrazine (yellow), while woven bone stained well with tartrazine. In addition, osteoid seams were identified by their affinity for tartrazine. Differential staining was abolished by pretreatment with periodic acid. Recently, accidental use of potassium permanganate in an acidified medium of pH 1.94, instead of pH 6.44, yielded unexpected results with a much sharper, consistent distinction between woven and lamellar bone. This probably reflects changes in the noncollagenous, interfibrillary matrix proteins of bone, but the exact reason(s) is not known. In our view, this serendipitous modification represents an advance over the previous method, and has allowed us to study the structure of bone in some of the systemic disorders, e.g., osteogenesis imperfecta, with greater ease than before. This method does, however, suffer the disadvantage of interfering with the intensity of the staining of any cartilaginous matrix, and the original application is still of value. Received October 26, 1999; accepted February 28, 2000.  相似文献   
34.
陈玲 《医疗设备信息》2005,20(11):70-70,32
在做LASIK手术时很多术者认为有一把好的角膜刀是非常重要的,其实还要有一支好的工程师队伍,这才是确保LASIK屈光手术成功的最基本条件。  相似文献   
35.
Terje Lømo 《Hippocampus》2009,19(7):633-648
The functional organization of the perforant path input to the dentate gyrus of the exposed hippocampus was studied in adult rabbits anesthetized with urethane and chloralose. Electrical stimulation of perforant path fibers caused excitation of granule cells along narrow, nearly transverse strips (lamellae) of tissue. Stimulation of granule cell axons (mossy fibers) in CA3 caused antidromic activation of granule cells along similar strips. Paired‐pulse stimulation revealed marked changes in granule cell excitability both within a lamella (on‐line) and for several mm off‐line along the septo‐temporal axis of the dentate gyrus. After the first pulse, granule cells were inhibited for up to about 100 ms and then facilitated for up to hundreds of ms. Feedback activity along mossy fiber collaterals exciting local inhibitory and excitatory neurons appeared to dominate in producing on‐ and off‐line inhibition and facilitation. Neurons mediating these effects could be inhibitory basket cells and other inhibitory interneurons targeting granule cells on‐ and off‐line. In addition, excitatory mossy cells with far reaching, longitudinally running axons could affect off‐line granule cells by exciting them directly or inhibit them indirectly by exciting local inhibitory interneurons. A scheme for dentate gyrus function is proposed whereby information to the dentate gyrus becomes split into interacting transverse strips of neuronal assemblies along which temporal processing occurs. A matrix of neuronal assemblies thus arises within which fragments of events and experiences is stored through the plasticity of synapses within and between the assemblies. Similar fragments may then be recognized at later times allowing memories of the whole to be created by pattern completion at subsequent computational stages in the hippocampus. © 2008 Wiley‐Liss, Inc.  相似文献   
36.
对解肌舒筋口服液中所合成分葛根素、麻黄碱进行鉴别,认为该方中挥发油制成芳香水与其他提取物混合溶解,不易产生分层,稳定性较佳,有效成分均匀分散,药品质量稳定。  相似文献   
37.
This report presents a Libyan child with congenital ichthyosis of the recessive lamellar variety complicated by severe ectropion of both upper and lower eyelids. Over a period of 12 months the degree of ectropion diminished and the anterior segments of the eyes were preserved using regular lubricating drops, vitamin A ointment and intermittent topical antibiotic therapy. Despite the pronounced initial upper eyelid ectropion no surgery was required to relieve the ectropion or prevent corneal exposure.  相似文献   
38.
Ultraviolet light (UVR) induces a myriad of cutaneous changes, including delayed disruption of the permeability barrier with higher doses. To investigate the basis for the UVB-induced barrier alteration, we assessed the epidermal lamellar body secretory system at various time points before and after barrier disruption with a single high dose of UVB (7.5 MED) to murine epidermis. Morphological data were correlated with changes in epidermal proliferation and lipid synthesis, indicative of lamellar body generation. Twenty-four hours following UVB, the stratum corneum (SC) is normal, but a layer of abnormal, vacuolated, and lamellar body (LB)-deficient cells is present, immediately beneath the stratum granulosum (SG)/SC interface. Immediately subjacent to this band of damaged cells, normal keratinocytes that contain intact LBs are present. By 72 h, concomitant with the appearance of a barrier abnormality, extensively damaged cells persist at the SC/SG interface, and abnormal lamellar membrane structures appear in the lower SC. Upper stratum spinosum (SS) and lower SG cells appear normal, with increased numbers of LBs. A barrier abnormality is still present at 96 h, in association with membrane abnormalities in the lower SC interstices, but up to four normal-appearing, subjacent SG cell layers are present. By 120 h, accelerated LB formation and precocious LB extrusion occur throughout the thickened SG; normal lamellar membranes are present in the lower SC; and barrier recovery is almost complete. Whereas, epidermal synthesis of the major barrier lipid species (i.e., cholesterol, fatty acids, and ceramides, including acylceramides) is reduced or unchanged at 24 and 48 h, it increases significantly 72 h after exposure to UVB. Therefore, the delayed disruption of the permeability barrier following acute UVB exposure results from the arrival of a band of lamellar body-incompetent (i.e., damaged) cells at the SG/SC interface. The subsequent, rapid recovery of the barrier, in turn, results from compensatory hyperplasia of subjacent, undamaged SS/SG cells, generating increased numbers and contents of LB. These results underscore the critical role of the stratum compactum in mediating barrier function, and suggest that beneficial therapeutic effects of UV exposure may be due to enhanced lipid production and barrier regeneration.  相似文献   
39.
目的:探索颅眶沟通瘤的B超诊断方法,以利于临床的诊断及治疗。方法:直接经上眼睑向眶内、颅内、副鼻窦内探查颅眶沟通瘤的声像图表现,有颞骨破坏者经颞部皮肤向眶内、颅内探查颅眶沟通瘤的声像图表现。结果:按肿瘤的主要部分所在的部位及侵袭范围将46例颅眶沟通瘤分为5型,即:颅眶型19例,颅眶鼻型3例,眶颅型7例,颅眶 颅内外型16例,鼻眶颅型1例。手术切除32例,依肿瘤的分类不同采用不同的手术入路,肿瘤全切除30例,次全切除2例。结论:B超诊断颅眶沟通瘤结果可靠,依据B超诊断按肿瘤的主要部分所在部位及侵袭范围分类,有利于手术方法的选择,提高了肿瘤的全切率。  相似文献   
40.
Five members of two generations of one family were affected with lamellar ichthyosis, suggesting autosomal dominant transmission. The clinical and histopathological characteristics of the cases described here are similar to those reported by Traupe et al. (1984) as autosomal dominant lamellar ichthyosis and thus confirm the existence of this new form of ichthyosis.  相似文献   
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