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11.
Thin slices of human tissues are characterized concerning reflection and transmission in a wavelength range from 400 to 1700 nm. The results are primarily useful to find a wavelength for the detection of subjacent blood vessels during surgical procedures, especially neurological surgery. The measurements have been conducted using a customized measuring station, utilizing two halogen bulb lamps and two spectrometers. This paper focuses on creating a data base with the optical properties of artery, brain, bone, nasal mucosa, and nerve. The spectral distributions are compared among each other, similarities and differences are pointed out. Each tissue has got unique spectral characteristics, whereas typical absorption bands can be found in the overall tissues, especially hemoglobin and water absorption bands. The reflectivity maxima are typically located in the red or near‐infrared. All the transmission maxima are located between 1075 nm and 1100 nm. The measurements have been conducted at the Institute of Anatomy at the University of Leipzig. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
12.
A two‐photon fluorescence lifetime (2P‐FLIM) microendoscope, capable of energetic metabolism imaging through the intracellular nicotinamide adenine dinucleotide (NADH) autofluorescence, at sub‐cellular resolution, is demonstrated. It exhibits readily usable characteristics such as convenient endoscope probe diameter (≈2 mm), fiber length (>5 m) and data accumulation rate (16 frames per second (fps)), leading to a FLIM refreshing rate of ≈0.1 to 1 fps depending on the sample. The spiral scanning image formation does not influence the instrument response function (IRF) characteristics of the system. Near table‐top microscope performances are achieved through a comprehensive system including a home‐designed spectro‐temporal pulse shaper and a custom air‐silica double‐clad photonic crystal fiber, which enables to reach up to 40 mW of ≈100 fs pulses @ 760 nm with a 80 MHz repetition rate. A GRadient INdex (GRIN) lens provides a lateral resolution of 0.67 μm at the focus of the fiber probe. Intracellular NADH fluorescence lifetime data are finally acquired on cultured cells at 16 fps.   相似文献   
13.
Protoporphyrin IX‐triplet state lifetime technique (PpIX‐TSLT) is a method used to measure oxygen (PO2) in human cells. The aim of this study was to assess the technical feasibility and safety of measuring oxygen‐dependent delayed fluorescence of 5‐aminolevulinic acid (ALA)‐induced PpIX during upper gastrointestinal (GI) endoscopy. Endoscopic delayed fluorescence measurements were performed 4 hours after oral administration of ALA in healthy volunteers. The ALA dose administered was 0, 1, 5 or 20 mg/kg. Measurements were performed at three mucosal spots in the gastric antrum, duodenal bulb and descending duodenum with the catheter above the mucosa and while applying pressure to induce local ischemia and monitor mitochondrial respiration. During two endoscopies, measurements were performed both before and after intravenous administration of butylscopolamine. Delayed fluorescence measurements were successfully performed during all 10 upper GI endoscopies. ALA dose of 5 mg/kg showed adequate signal‐to‐noise ratio (SNR) values >20 without side effects. All pressure measurements showed significant prolongation of delayed fluorescence lifetime compared to measurements performed without pressure (P < .001). Measurements before and after administration of butylscopolamine did not differ significantly in the duodenal bulb and descending duodenum. Measurements of oxygen‐dependent delayed fluorescence of ALA‐induced PpIX in the GI tract during upper GI endoscopy are technically feasible and safe.  相似文献   
14.
目的:探讨鼻内镜下电凝止血结合明胶海绵微填塞治疗难治性鼻出血的临床特征和疗效。方法:回顾性分析我院2011 年1 月至2015 年1 月收治的203 例难治性鼻出血患者的临床资料,探讨发病季节、发病年龄、出血部位以及发病年龄与出血部位的 相关性。结果:203 例患者经鼻内镜下电凝止血结合明胶海绵微填塞治疗,全部治愈,其发病特征具有明显的季节性,40~60 岁多 见(41.9%),下鼻道出血最常见(30.0%),老年人以鼻腔后下部位出血为主,青中年以鼻腔前上部位出血为主。结论:鼻内镜下电凝 结合微填塞治疗难治性鼻出血微创、安全、有效,值得推广。  相似文献   
15.
Selective binding of biotinylated albumin to the lymphoid microvasculature   总被引:1,自引:1,他引:0  
Chemically modified albumin binds to the surface of microvascular endothelia lining the vessel wall in several tissues. In this paper, we report that following their biotinylation, ovalbumin (bioOVA) and bovine serum albumin (BSA) [biotinyated albumin (bioAlb)] showed heterogeneous binding to distinct vascular subsets in different lymphoid tissues. The binding of bioAlb could be demonstrated both by fluorescent and enzymohistochemical techniques. In the spleen, the reaction was restricted to the red pulp sinuses whereas the white pulp vessels (including the central arteriole) and the marginal sinus were negative for bioAlb binding. In lymph nodes, the strongest labeling was observed in the medullary sinuses. In the thymus, the most prominent labeling of capillaries was restricted to the corticomedullary area where it was found to be less intense compared with the splenic reaction. The splenic reactivity of bioAlb in the mouse was defined using antibodies against endothelial cell subsets in distinct vascular beds in the red pulp and marginal zone, respectively. The bioAlb-binding elements of the splenic red pulp sinus architecture corresponded to the display of hyaluronan receptor stabilin-2 and subset-specific marker IBL-9/2 while they differed from the expression pattern of both the complementary red pulp sinus subset and the marginal sinus-lining cells expressing MAdCAM-1 antigen, respectively. Similar red pulp sinus-restricted reactivity could be demonstrated in the human, rat, and guinea pig. The use of bioAlb may thus offer a reliable probe for the histological identification of select microvascular endothelia in lymphoid tissues.  相似文献   
16.
目的:通过临床非随机性对照研究,比较经胸前壁入路内镜甲状腺手术与传统甲状腺手术在手术时间、术中出血量、术后引流量、术后疼痛、功能恢复、术后住院时间、住院费用及美容效果上的不同,探讨经胸前壁入路内镜甲状腺手术的可行性及临床效果。方法:回顾性分析86例甲状腺手术,其中46例患者采用经胸前壁入路内镜甲状腺手术的患者为内镜组,40例行传统甲状腺手术为传统组。结果:两组患者均顺利完成手术,术后恢复良好,均未发生术后大出血、喉返神经、喉上神经及甲状旁腺损伤等并发症。两组患者的术后住院时间及术后引流量无显著差异。与传统组比较,内镜组手术时间明显延长(P<0.05),术中出血量明显减少(P<0.05),术后疼痛明显降低(P<0.05),功能恢复即术后自行下床洗漱时间明显缩短(P<0.05),住院费用显著增加(P<0.05),手术美容效果满意度明显提高(P<0.05)。结论:相对传统甲状腺手术,经胸前壁入路内镜甲状腺手术具有切口小、出血量少、术后疼痛轻、功能恢复快、美容满意度高等优点,是治疗甲状腺疾病安全、有效的手术方法。  相似文献   
17.
Splenic sinus endothelial cells, which adhere through tight and adherens junctions, regulate the passage of blood cells through the splenic cord. The objective of this study was to assess the localization of tight junctional proteins, claudin-5 and ZO-1 in the sinus endothelial cells of rat spleen and to characterize spatial and functional relationships between tight and adherens junctions. Immunofluorescence microscopy of tissue cryosections demonstrated that claudin-5, ZO-1, and α-catenin were distinctly localized in the junctional regions of adjacent endothelial cells. Immunogold electron microscopy demonstrated claudin-5 localized in the tight-junctional fused membranes of adjacent endothelial cells. Immunogold labeling for ZO-1 was localized not only in the tight-junctional-fused membranes of endothelial cells but also in the junctional membrane. α-Catenin was intermittently localized along the juxtaposed junctional membranes of adjacent endothelial cells. Double-staining immunogold microscopy for claudin-5 and ZO-1, claudin-5 and VE-cadherin, ZO-1 and VE-cadherin, and ZO-1 and α-catenin demonstrated that ZO-1 was closely localized to VE-cadherin and α-catenin in their juxtaposed membranes of endothelial cells. Thus, ZO-1 might play an important role in regulating the cell–cell junctions of sinus endothelial cells for blood–cell passage through splenic cords. This work was supported by a Grant-in-Aid for Scientific Research (C), Japan.  相似文献   
18.
The Sinus Node (SN) of the heart is the natural pacemaker driving electrical impulses into the atria, an ordinary excitable medium. In order to avoid wave interference, the SN operation must be of such a nature that no reflections from the atria should occur. It is shown that such a behavior is achieved when the SN operates in a nonlinear dynamical regime situated away from relaxation.  相似文献   
19.
20.
Summary Seven morphologically different types of neurosecretory granules have been found in the axon terminals of the sinus gland of the blue crab, Callinectes sapidus. They differ from each other in size, shape, staining characteristics, solubility characteristics, core matrix characteristics, axon terminal matrix characteristics, presence or absence of space between the granule membrane and granule core matrix, and frequency of occurrence. Five of the types are segregated in different axon terminals and are believed to represent different hormone-protein complexes. Two of the types, which have lost part or all of their granular contents, are thought to be variants of the other five types. The differences in granular morphology are better revealed by some fixation procedures than others. Palade's acetate-veronal buffered osmium tetroxide, in particular, reveals striking differences. The following observations suggest that different hormone-protein complexes are segregated in different axon terminals and that these complexes may be morphologically distinguished at the level of the electron microscope.Supported by USPHS-NIH Training Grant GM-00669 and Grant GB-7595X from the National Science Foundation.  相似文献   
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