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51.
Diarrhea has been reported as an early, mild, and uncommon complication of carbamazepine (CBZ) therapy. We report three cases of intractable diarrhea induced by CBZ necessitating discontinuation of the drug. 相似文献
52.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
53.
54.
55.
Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
56.
57.
G M Yasargil L Macintyre R Doucette B Visheau M Holmes J Diamond 《The Journal of comparative neurology》1988,270(2):301-312
Low-threshold mechanosensory nerves in the adult rat differ both from their counterparts in lower vertebrates and from high-threshold nociceptive nerves in mammals in that they appear not to undergo collateral sprouting into adjacent denervated skin, although they will clearly regenerate into it after they are damaged. We have now studied the growth capabilities of the low-threshold nerves supplying touch domes, the visible mechanosensory structures scattered throughout the hairy skin. Touch domes in the rat are often multiply innervated. A serendipitous observation on such domes allowed us to investigate the possibility that a functional collateral sprouting of their nerves can indeed occur, but only to a spatially very restricted extent, e.g., within the confines of a partially denervated dome. We used a "prodder" with a tip diameter of 16 micron to examine the mechanosensory profile across single domes that were preselected as being supplied by only two axons, one running in each of two adjacent dorsal cutaneous nerves (DCNs). Simultaneous recordings were made of the afferent discharges evoked in these nerves when the prodder was applied at about 17 or more locations on a selected dome; the spatial resolution was better than 55 micron. We found that within such a shared dome, one axon can supply a discrete territory (its "domain"), which may or may not overlap with the corresponding domain of the other axon. In a preliminary electron microscopic study, we found no evidence for a sharing of single Merkel cells, which are the specialized sensory cells in touch domes, even in the regions of a shared dome where two domains overlapped; each innervated Merkel cell appeared to be contacted by a single nerve ending, implying that in a shared dome each axon probably supplies an exclusive subpopulation of the Merkel cells. We tested for functional collateral sprouting by eliminating one nerve to a shared dome, and at a selected time thereafter mapping the domain of the remaining axon to see whether it had enlarged. The result was the same whether the two domains initially had a region of overlap or not; no expansion of the surviving domain occurred over postoperative periods up to 4 months (an expansion of the domain by 55 micron would have been detected). Thus functional collateral sprouting had failed to occur.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
58.
Rats with lesions of the area postrema (APX) are known to exhibit an enhanced intake of highly palatable foods such as sweetened condensed milk and cookies. These observations suggest the possibility that APX rats find these foods more rewarding and will work harder to obtain these foods. Sham and APX rats were tested on fixed ratio (FR) and progressive ratio (PR) schedules. APX rats consistently pressed more times to receive sucrose solution and attained both FR 3 and FR 5 criteria significantly faster than sham-lesioned control rats. Furthermore, rats with APX had significantly higher break points than sham-lesioned control rats on a progressive ratio schedule. These results support the hypothesis that rats with lesions of the area postrema will consistently work harder to obtain a highly palatable food reward. 相似文献
59.
Bacteriocin typing has been described previously and proposed for typing gonococci. A survey has been made of 150 strains of N. gonorrhoeae from various places to determine the feasibility of a gonocin typing system. All strains were found to produce an inhibitory substance which inhibited all strains of gonococci tested, one strain of Neisseria flavescens, two strains of Neisseria meningitidis, as well as the producing strain itself. The inhibitory activity was enhanced by supplementary glucose, reduced by supplementary serum, and unaffected by the addition of HEPES buffer, by the temperature of incubation, or by the exposure of potential producer strains to sublethal concentrations of mitomycin C. This nonspecific inhibitory activity differed from that of a putative bacteriocin produced by a strain of N. meningitidis, in that the latter inhibited most other meningococci but not the producer strain itself. Bacteriocinogeny has not yet been convincingly demonstrated in N. gonorrhoeae, and gonocin typing has not yet been shown to be feasible. Production of the nonspecific inhibitor may have obscured past attempts to demonstrate type-specific gonococcal bacteriocin. 相似文献
60.
Expression of opioid peptides in tumors 总被引:3,自引:0,他引:3
D G Bostwick W E Null D Holmes E Weber J D Barchas K G Bensch 《The New England journal of medicine》1987,317(23):1439-1443
We looked for opioid peptides and their precursors in 108 tumors of both neuroendocrine and nonneuroendocrine origin, using a monoclonal "pan-opioid" antibody, 3-E7, which recognizes the tetrapeptide Tyr-Gly-Gly-Phe (the sequence responsible for pharmacologic activity in all known opioid peptides), in conjunction with polyclonal antibodies directed against representative peptides of each of the three precursors (alpha-endorphin, [met]enkephalin-Arg-Gly-Leu, and dynorphin B). Using the avidin-biotin immunoperoxidase technique, we observed consistent cytoplasmic immunoreactivity (at least focally) in all of 15 adrenal pheochromocytomas, all of 6 thyroid medullary carcinomas, and all of 5 pituitary adenomas. Opioid staining was also observed in parathyroid adenomas (8 of 9), pancreatic islet-cell tumors (7 of 10), carcinoid tumors from various sites (18 of 26), and paragangliomas (1 of 2). There was no immunoreactivity in pulmonary small-cell carcinomas, Merkel-cell tumors of skin, neuroblastomas, or any of the non-neuroendocrine tumors examined. The expression of alpha-endorphin, [met]enkephalin-Arg-Gly-Leu, and dynorphin B varied from tumor to tumor; however, positive staining with the "pan-opioid" antibody was found in each tumor containing at least one of the three precursors. Opioid peptide immunoreactivity was also detected in non-neoplastic cells of the adrenal medulla, pancreatic islets, pituitary, intestinal and bronchial mucosa, and intestinal myenteric plexuses. We conclude that opioid expression within tumors is most likely due to enhanced expression of a normal cell product and that opioid peptides are useful markers of neuroendocrine differentiation in many tumors. 相似文献