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971.
972.
973.
The present study was undertaken to determine the frequency with which undigested meat fibres in the stool could be found after partial gastrectomy. A sample of stool was examined in 61 patients who had undergone a partial gastrectomy and in 92 control patients. The age ranges and average ages of both groups were similar. The stools of 77 of the 92 control patients contained well-digested meat fibres, 14 showed partially digested fibres, and one patient had completely undigested meat fibres. In the postgastrectomy group, 44 of 61 patients had well-digested meat fibres and 17 showed partially digested fibres in their stools. None showed undigested fibres. The present study demonstrated that the finding of undigested meat fibres is as infrequent in postgastrectomy patients as in control patients. If undigested meat fibres are found in the stools of postgastrectomy patients, it is suggestive of pancreatic exocrine insufficiency. 相似文献
974.
Zusammenfassung Es wird über Versuche anBranckiostoma lanceolatum berichtet, in denen obere Urmundlippe der jungen Gastrula in das Blastocöl gleich alter anderer Gastrulä implantiert wurde.Bei Zuchttemperaturen von 17–20° C übten die entstandenen sekundären Chorden keine Induktionswirkung auf das darüberliegende nichtneuralvirtuelle Wirtsektoderm aus.Bei Temperaturen von 22–24° C trat in der Mehrzahl der Fälle Neuralinduktion ein, womit die Ergebnisse vonTung, Wu undTung (1962) bestätigt sind.Das Ausbleiben der Induktion bei niederer Temperatur bestätigt das Ergebnis V.Ubischs von 1963, wo auch bei einer Zuchttemperatur von 18° C Induktion ausblieb.Es wird die Frage diskutiert, ob die Versuchsergebnisse darauf hindeuten, daßBranchiostoma ein werdendes oder ein reduziertes Wirbeltier sei.Es wird weiterhin auf Grund der gefundenen Temperaturabhängigkeit der sekundären Neuralinduktion die Frage diskutiert, wieweit Induktion in der normalen Entwicklung stattfindet und eine Rolle für die normale Entwicklung spielt oder ob diese nur bei Störung der normalen Struktur des Keimes als ein experimentell erzeugtes Phänomen eintritt. 相似文献
975.
976.
A Note on a Simple and Rapid Method of Bacteriological Sampling by Means of Agar Sausages 总被引:5,自引:4,他引:1
L. Ten Cate 《Journal of applied microbiology》1965,28(2):221-223
A rapid and simple method is described for the bacteriological examination of contaminated surfaces. It uses an imprint process with 'agar sausages' sterilized in polyamide casings. 相似文献
977.
In the last few years, we have focused our research effort on the magnetic resonance spectroscopic (NMR) studies of organ transplantation in the rat. P-31 NMR was employed to study changes in high-energy phosphates, intracellular pH in vivo of transplanted kidneys either during normal function, while undergoing the rejection process or subjected to other insults (e.g. ischemia, cyclosporine nephrotoxicity, urinary obstruction) which may also cause graft dysfunction. Nuclear magnetic resonance (NMR) parameters, specifically relative peak areas and intracellular pH, accurately distinguished among the different causes of graft dysfunction. Ureteral obstruction was clearly identified by elevations in the phosphodiester/urine phosphate peak. Ischemia and rejection were both associated with increases in inorganic phosphates and phosphomonesters and decreases in the beta-phosphate peak of adenosine triphosphate but were distinguishable from each other by differences in intracellular pH which was normal in rejected allografts (7.33 +/- 0.07, n = 3) and low in ischemic allografts (7.00 +/- 0.05, n = 3, p less than 0.05). Grafts insulted with cyclosporine toxicity were not distinguishable from normal allografts by any of the parameters studied. To determine the temporal relationship of NMR changes in allograft rejection, similar studies were performed serially in a group of rejecting (R) kidneys (n = 7) and compared with a control group of nonrejecting (NR) kidneys (n = 7). Major decrease in adenosine triphosphate (ATP) with increases in Pi and a marked increase in the Pi/ATP ratio were noted in the R allografts over time. The R allografts could be completely segregated from the NR allografts on the basis of the Pi/ATP ratio by day 7. These data suggest that 31P NMR spectroscopy may have potential clinical application in differentiating among the causes of graft failure of human renal allografts. 相似文献
978.
J. L. Taylor 《The Australian journal of anthropology》1989,19(2):112-125
This paper is concerned with the ongoing intense interest in Thailand of two controversial urban Buddhist movements which have appeared since the beginning of the seventies, Santi Asok and Thammakaai. Essentially, I view both as a resonance of the perceived need for ‘change’ among an articulate aspiring new middle class. I also argue that both Santi Asok and Thammakaai in their expressions — Thammakaai the specious discursive function of capital, Santi Asok by confrontation and spurning what they consider an ‘amoralistic’ establishment — are predicating a radical critique of the Thai social order, a call for collective ‘inner-worldly activism’ and ‘individualistic’ reflexive response to convention. 相似文献
979.
The secretory organelles of Plasmodium knowlesi were studied ultrastructurally to examine their mode of action during invasion. The formation of lamellar structures in merozoite rhoptries within late stage schizonts is prevented by the protease inhibitors chymostatin and leupeptin. Under normal conditions vesicles lined by 6-nm membranes are formed in rhoptries during erythrocyte invasion. Stereoscopic viewing of tilted sections shows that where the merozoite apex contacts the parasitophorous vacuole (PV) membrane during invasion, a domed elevation of the PV surface lies within the mouth of the rhoptry duct in contact with the secretory matrix. The membrane of the early invasion pit is thinner (6 nm) than the red cell membrane elsewhere, and sheets of lamellar material are frequently present on the invasion pit surface. These findings support the proposal that the rhoptry-microneme complex is capable of generating membranous material and inserting it into the red cell surface in a controlled manner to create the parasitophorous vacuole. On the basis of this model, measurements from serial sections show that the rhoptries could provide enough material to create a membrane lining the parasitophorous vacuole, and, with the contribution of the microspheres, could double it to accommodate the early ring stage of the parasite. 相似文献
980.
L. N. Drozdov-Tikhomirov A. T. Grizhebovskaya E. C. Mil'ko 《Engineering in Life Science》1989,9(5):453-460
An attempt is made to give a quantitative estimation of a possible contribution of the dissociation process in the formation of the heterogeneous population structure for the Rhodococcus rubropertinctus (Micobacterium lacticolum) in continuous cultivation. This estimation is realised with the help of a constructed mathematical model of the process. The model equations obtained describe particular biomass changes for R-, S- and M-dissociants and changes for substrate (glucose) concentration within the chemostate in continuous cultivation. Next, contributions to dissociant biomass changes were taken into account: (1) cell reproduction (each dissociant has its own specific growth rate depending on the substrate concentration), (2) cell outflow (in proportion to dissociant biomass) and (3) dissociation (dissociant genotype change during reproduction occurs for each dissociant with its own specific frequency). It is determined that if substrate growth constants are equal the rapidly growing dissociants (possessing maximal μmax) outs the rest of them, and the greater the speed of the flow the less the time to reach a steady-state distribution of the dissociant biomasses. But, at the same time the slowly growing dissociant can become dominant in the population if it has a lower substrate growth constant. 相似文献