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41.
M P Joseph M L Goodman B Z Pilch F R Bieber L B Holmes E Reardon 《Head & neck surgery》1986,8(6):456-462
Heterotopic cervical salivary gland tissue was found in a 4-yr-old girl with branchial and otologic abnormalities. Her mother and sister also had heterotopic cervical salivary tissue in association with anomalies that suggest the branchio-otorenal (BOR) syndrome. Heterotopic cervical salivary gland tissue may result from abnormal branchial development. 相似文献
42.
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
43.
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
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47.
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
48.
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
49.
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
50.
Ultrastructure of the early human implantation in vitro 总被引:1,自引:1,他引:1
Lindenberg Svend; Hyttel Poul; Lenz Sunzan; Holmes Poul V. 《Human reproduction (Oxford, England)》1986,1(8):533-538
Four hatched human blastocysts obtained after in-vitro fertilizationand development were placed on monolayer cell cultures of humanendometrial epithelium, and subsequently examined by transmissionelectron microscopy. All four blastocysts became adherent tothe monolayer and three implanted and exhibited outgrowth oftheir trophoblastic cells. During implantation the blastocystsdifferentiated into mural and polar trophoblastic cells, andembryonic cells including endodermal cells. The endometrialcells were displaced and stacked into a multilayer at the peripheryof the implantation sites, allowing the trophoblastic cellsto come in contact with the culture dish. The endometrial cellsdisplayed local exo- or endo-cytosis where they contacted thetrophoblastic cells. The trophoblastic cells were not observedto be phagocytosing endometrial cells. These observations suggestthat human blastocysts portray an intrusive type of implantationduring the initial stages. 相似文献