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191.
Research in translational medicine often requires high-resolution characterization techniques to visualize or quantify the fluorescent probes. For example, drug delivery systems contain fluorescent molecules enabling in vitro and in vivo tracing to determine biodistribution or plasma disappearance. Albeit fluorescence imaging systems with sufficient resolution exist, the sample preparation is typically too complex to image a whole organism of the size of a mouse. This article established a mesoscopic imaging technique utilizing a commercially available cryo-microtome and an in-house built episcopic imaging add-on to perform imaging during serial sectioning. Here we demonstrate that our automated red, green, blue (RGB) and fluorescence mesoscope can generate sequential block-face and 3-dimensional anatomical images at variable thickness with high quality of 6 µm × 6 µm pixel size. In addition, this mesoscope features a numerical aperture of 0.10 and a field-of-view of up to 21.6 mm × 27 mm × 25 mm (width, height, depth).  相似文献   
192.
An ultrastructural synaptic analysis based on observations from 33 serial thin-sections of the inner plexiform layer in a volume sample of midperipheral human retina is presented. Of the 152 identifiable neuronal processes 7lpar;total 187) 14 were bipolar, 112 amacrine, and 26 ganglion. One hundred and forty-seven synapses were present — 31 bipolar (ribbon) and 116 amacrine (conventional). The ribbon synapses were divided on the basis of their postsynaptic processes into: amacrine, ganglion (16); amacrine, amacrine, ganglion (9) amacrine, amacrine (3) amacrine, amacrine, amacrine (1) ganglion (2), both incomplete in sections(. Of the 116 conventional synapses, 28% were amacrine-bipolar, 34% amacrine-amacrine and 38% were amacrine-ganglion. The occurrence of extra amacrine process(es) and the occasional absence of a ganglion cell dendrite at bipolar (ribbon) synapses, as well as the relative abundance of amacrine-amacrine (conventional) synapses, suggests a relatively greater role of amacrine cells in mediating visual transformations in the midperipheral human retina than has been described previously.  相似文献   
193.
Tick-borne diseases are a serious threat to both public and veterinary health. In this study, we used high-throughput sequencing to characterize the virome of three tick species implicated in the spread of vector-borne disease throughout Croatia. Ten viruses were identified, including seven potential novel species within the viral families Flaviviridae, Nyamiviridae, Rhabdoviridae, Peribunyaviridae, Phenuiviridae, and Nairoviridae.  相似文献   
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用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。  相似文献   
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Chemical analyses of plankton and highly toxic mussel samples collected in eastern Canada during an intense bloom of the dinoflagellate Alexandrium tamarense established the presence of a complex mixture of paralytic shellfish poisoning (PSP) toxins. Application of a newly developed technique, hydrophilic interaction liquid chromatography-mass spectrometry, confirmed the identities of the known toxins and revealed the presence in the mussels of five saxitoxin analogues (M1-M5) that were not present in the plankton. Four of these compounds were isolated and their structures established by tandem mass spectrometry, 1D- and 2D-NMR spectroscopy, and chemical interconversion experiments. One of these was found to be 11beta-hydroxysaxitoxin (M2), while the other three were found to be new saxitoxin analogues, namely, 11beta-hydroxy-N-sulfocarbamoylsaxitoxin (M1), 11,11-dihydroxy-N-sulfocarbamoylsaxitoxin (M3), and 11,11-dihydroxysaxitoxin (M4). Compound M5 remains unidentified because of insufficient material for characterization.  相似文献   
199.
Background High intensity focused ultrasound (HIFU) is a novel method which offers the non-invasive ablation of tissues without harming overlying organs or skin. It has been introduced successfully in urology for the ablation of prostatic hyperplasia and seems to be promising in the treatment of uterine fibroids. In this study we aimed to examine the feasibility and possible side effects of HIFU treatment of uterine tissues using an experimental mobile HIFU unit with ultrasound guidance. Methods For these experiments, a 1.07 MHz ultrasound source was used which allows treatment depths between 0 and 10 cm. In 12 patients scheduled to have abdominal hysterectomy, 5–60 impulses of HIFU were applied through the intact skin upon uterine tissues directly prior to the surgical procedure. Tissue intensities lay between 3,200 and 6,300 W/cm2 and a fixed pulse length of 4 s was used. Results No side effects were encountered other than one first-degree skin burn and the treatment was well tolerated. Histology showed clearly demarcated coagulative necrosis in the targeted tissues. Treatment was concluded in less than 45 min for each patient. Conclusion Focused ultrasound is an effective method to selectively destroy tissue within the uterus and the transabdominal access route is very feasible. This study shows that a mobile ultrasound source can be used safely and effectively to destroy uterine tissues, such as fibroids, without major side effects.  相似文献   
200.
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