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In the isolated perfused rat pancreas, D,L-difluoromethylornithine, tested at a concentration of 3 mmol/L, failed to affect the release of glucagon and insulin caused, over 15 min stimulation, by either L-arginine or L-ornithine (2.0, 5.0 or 10.0 mmol/L) in the presence of either 3.3 or 5.6 mmol/L D-glucose. The inhibition of ornithine decarboxylase also failed to affect the release of glucagon provoked by either L-leucine (2 or 3 mmol/L) or L-glutamine (2 mmol/L) and the secretion of insulin stimulated by a rise in glucose concentration from 5.6 to 10.6 mmol/L. These data are interpreted to suggest that the rapid generation of polyamines from either L-arginine or L-ornithine does not play any significant role in the immediate glucagonotropic and insulinotropic action of these cationic amino acids. 相似文献
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AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 相似文献
6.
Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
7.
Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice. 相似文献
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Background
There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. 相似文献9.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
10.
The possible priming by D-glucose of metabolic events in islets from control rats and Goto-Kakizaki rats (GK rats) was investigated by first incubating the islets for 120 min either in the absence of any exogenous nutrient or presence of 16.7 mM D-glucose. The islets were then incubated for a second period of 120 min either at 2.8 mM or 16. 7 mM D-glucose, the hexose being now mixed with tracer amounts of D-[U-14C]glucose and D-[5-3H]glucose. In islets from control rats first incubated in the absence of exogenous nutrient the hierarchy in the 16.7 mM/2.8 mM ratio for metabolic variables was as follows: D-[U-14C]glucose oxidation > D-[5-3H]glucose utilization and D-[U-14C]glucose conversion to amino acids > D-[U-14C]glucose conversion to acidic metabolites. When the islets from control rats were first incubated in the presence of 16.7 mM D-glucose, the preferential stimulation of mitochondrial oxidative events at high hexose concentration, as documented by the increase in the paired ratio between D-[U-14C]glucose oxidation and D-[5-3H]glucose utilization, was further enhanced. The 16.7 mM/2.8 mM ratio for the conversion of D-[U-14C]glucose to amino acids, relative to that for D-[U-14C]glucose conversion to acidic metabolites, was much lower, however, after a first incubation in the presence of D-glucose, rather than in its absence, probably as a result of the progressive exhaustion of endogenous amino acids considered as transamination partners. The major differences between these results and those obtained in islets from GK rats consisted, in the latter animals, in i) higher absolute values for all metabolic fluxes, ii) lower 16.7 mM/ 2.8 mM ratios, iii) lower paired ratio between D-[U-14C]glucose oxidation and D-[5-3H]glucose utilization, and iv) absence of a priming effect of D-glucose (16.7 mM) upon such a paired ratio in the islets incubated at 16.7 mM D-glucose during the second incubation. Taken as a whole, these observations confirm that the preferential stimulation of mitochondrial oxidative events, in response to a rise in D-glucose concentration, is impaired in islets from GK rats and extend this knowledge to the priming action of D-glucose, in high concentration, on the catabolism of the hexose during a subsequent incubation. 相似文献