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871.
LP Krustev TA Tashev AA Popov JZ Apostolov BJ Borov MS Stefanova 《Canadian Metallurgical Quarterly》1976,20(6):597-603
The subjection of rats with body weight 150 +/- 10 g to complete starvation for a period of four days leads to a diminution of total protein, total lipids, blood sugar, body weight and liver weight. Lipid dystrophy develops in the liver, as well as deposition of lipofuscin-like pigment and atrophy. Lipid dystrophy and desposition of pigment increase during the first three days and abruptly decrease during the fourth. Atrophy is a progressive process. The delineation of three phases in the atrophic - dystrophic process is possible with the application of histological, enzyme-histochemical, morphometric, biochemical and electron microscopic methods: Phase I (first 24 hours) - a common adaptive phase. It engages both the liver, which must utilize the increased nutrients from the organism depots and the homeostatic mechanisms of the organism as a whole. Phase II - (second and third 24 hours) - alterative-restorative, manifested markedly at the liver parenchimal level and especially by autophagic lysosome function. Phase III - (fourth 24 hours) - alterative. Exhaustion of adaptive-restorative liver process (and the hepatocyte in particular), and the organism as a whole as well. 相似文献
872.
873.
Tardyferon was administered to 51 patients with iron deficiency anaemia. The drug was very well tolerated and even after administration to fasting patients it was tolerated well by 92% of patients. The iron absorption curve was on the average twice as high after 1 hour and increased up to 3 hours. A significant therapeutic effect with raised haemoglobin level by 10--27% was obtained after 4--6 weeks of treatment in 44 patients (86%). In the remaining cases the improvement was less pronounced. 相似文献
874.
875.
J Riedlberger C Amsler M Doser U Straumann P Tru?l D Bailey S Barlag U Gastaldi R Landua C Sabev KD Duch M Heel H Kalinowsky F Kayser E Klempt B May O Schreiber P Weidenauer M Ziegler W Dahme F Feld-Dahme U Schaefer WR Wodrich S Ahmad JC Bizot B Delcourt J Jeanjean H Nguyen N Prevot EG Auld DA Axen KL Erdman B Howard R Howard BL White M Comyn G Beer GM Marshall LP Robertson M Botlo C Laa H Vonach 《Canadian Metallurgical Quarterly》1989,40(6):2717-2731
876.
This investigation was stimulated by the historical confusion concerning the identity of certain pretectal nuclei and by large differences reported between species with respect to which nuclei receive retinal innervation. Subcortical visual nuclei were studied using immunohistochemistry to identify retinal projections labeled following intraocular injection of cholera toxin, b fragment. In addition, neuropeptide Y (NPY) or enkephalin (ENK) immunoreactive cells and fibers were also evaluated in the retinorecipient pretectal and thalamic areas. The results confirm the established view that the retina directly innervates the nucleus of the optic tract (NOT), posterior (PPT), and olivary pretectal (OPT) nuclei. However, the retina also innervates the hamster medial (MPT) and anterior (APT; dorsal division) pretectal nuclei, results not previously reported in rodents. A commissural pretectal area (CPT) sparsely innervated by retina is also described. The data show for the first time that the posterior limitans nucleus (PLi) receives a moderately dense, direct retinal input. The PLi does not project to the cortex and appears to be a pretectal, rather than thalamic, nucleus. All retinal projections are bilateral, although predominantly contralateral. The PLi contains a moderately dense plexus of NPY- and ENK-IR fibers and terminals. However, peptidergic fibers also traverse the ATP and connect with the dorsomedial pretectium. The OPT contains ENK- and NPY-IR neurons and fibers, but is specifically identifiable by a moderately dense plexus of ENK-IR terminals. Numerous ENK-IR neurons are found in the NOT and PPT. The latter also has moderate numbers of ENK-IR fibers and terminals, but few NPY-IR neurons or fibers. The MPT contains modest numbers of ENK-IR fibers. The APT has no NPY-IR neurons or terminals, but an occasional ENK-IR neuron is seen and there is sparse ENK-IR innervation. Peptidergic innervation of the visual nuclei does not appear to be derived from the retina. The results show a set of retinally innervated, contiguous nuclei extending from the thalamic ventrolateral geniculate nucleus dorsomedially to the midbrain CPT. These nuclei plus the superior colliculus comprise a dorsal "visual shell" embracing a central core of caudal thalamus and rostral midbrain. 相似文献
877.
Klostranec JM Xiang Q Farcas GA Lee JA Rhee A Lafferty EI Perrault SD Kain KC Chan WC 《Nano letters》2007,7(9):2812-2818
Through the convergence of nano- and microtechnologies (quantum dots and microfluidics), we have created a diagnostic system capable of multiplexed, high-throughput analysis of infectious agents in human serum samples. We demonstrate, as a proof-of-concept, the ability to detect serum biomarkers of the most globally prevalent blood-borne infectious diseases (i.e., hepatitis B, hepatitis C, and HIV) with low sample volume (<100 microL), rapidity (<1 h), and 50 times greater sensitivity than that of currently available FDA-approved methods. We further show precision for detecting multiple biomarkers simultaneously in serum with minimal cross-reactivity. This device could be further developed into a portable handheld point-of-care diagnostic system, which would represent a major advance in detecting, monitoring, treating, and preventing infectious disease spread in the developed and developing worlds. 相似文献
878.
LP Kotra Y Xiang MG Newton RF Schinazi YC Cheng CK Chu 《Canadian Metallurgical Quarterly》1997,40(22):3635-3644
Following the recent discoveries that some L-nucleosides are more or equal potent than their D-counterparts, we synthesized 2'-deoxy-2',2'-difluoro-L-erythro-pentofuranosyl nucleosides as potential antiviral agents. The target compounds were synthesized via the key intermediates 7a or 7b from L-gulono gamma-lactone. Compound 2 was oxidatively cleaved and coupled with ethyl bromodifluoroacetate in the presence of activated zinc under Reformatsky conditions to obtain a diasteomeric mixture of 4(R) and 4(S), in a 4:1 ratio. The major 4(R) isomer was cyclized and treated appropriately to obtain the mesylate 8a or 8b, which was condensed with various silyl-protected pyrimidines. Condensation of the alcohol 7a or 7b with 6-chloropurine under Mitsunobu conditions afforded the 6-chlorpurine analogs 53a or 53b and 54a or 54b. Further treatment of the compounds 53a, 54a and 53b, 54b afforded the inosine and adenine derivatives 57-60, respectively. The condensation of 2-amino-6-chloropurine with compound 8a and subsequent treatment with 2-mercaptoethanol/sodium methoxide afforded the guanine analogs 63 and 64. All of the synthesized nucleosides 31-52, 57-60, 63, and 64 were evaluated for antiviral activity and for cellular toxicity. Adenine derivative 57 showed a moderate activity against HIV-1 in PBM cells (3.4 microM). None of the other compounds showed any significant activities against HIV-1, HBV, HSV-1, HSV-2, and toxicity in Vero, CEM, and PBM cell lines up to 100 microM. The X-ray structure of the 5-iodocytosine analog showed a 2'-exo/3'-endo conformation for the carbohydrate moiety, which is different from those of the biologically active compounds (-)-FTC and L-FMAU. 相似文献