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81.
Postembolic colonic infarction 总被引:12,自引:0,他引:12
82.
AIMS: The aim of this study was to theoretically explore the relationship between the tube law (TL) of the urethra and the pressure-flow (p-Q) relationship during micturition. The understanding of this relation is important for the evaluation of outlet obstruction by urodynamic interpretation of p-Q plots. METHODS: We simulated the outlet function by a lumped theoretical model, and suggested how the TL can be used to quantitatively predict the p-Q relationship of the system. Our analysis considered the relation between the TL and the steady state p-Q plot for various TLs including the hysteresis of the pressure-area relationship. RESULTS AND CONCLUSIONS: The inclusion of pressure losses distal to the flow controlling zone and experimentally measured p-A relations of the urethra in the model lead to the predictions that flow in the flow controlling zone is not always critical but is often in the sub-critical range, that an increase in abdominal pressure can increase the flow under certain conditions, and that hysteresis in the pressure-area relation is correlated to the hysteresis in the p-Q plot. 相似文献
83.
84.
HO Garland † K Hamilton S Freeman C Burns M Cusack RJ Balment 《Clinical and experimental pharmacology & physiology》1999,26(10):803-808
1. Infusion experiments were performed on chronically catheterized conscious rats to assess kidney function before and after the induction of diabetes mellitus with streptozotocin. 2. Two infusion regimens were used, a conventional constant-infusion protocol and a novel computer-driven, servo-controlled fluid replacement technique. The latter enables body fluid status to be maintained throughout a study occasion by servo-controlled replacement of spontaneous urinary fluid losses. 3. The chronically catheterized conscious rat infused using a servo-controlled system appears to be the optimum model for a study of diabetic renal function. The conscious preparation circumvents problems associated with anaesthesia and acute surgery. The servo-controlled infusion protocol maintains the altered fluid status of the diabetic condition. Both hyperfiltration and polyuria, characteristics of human diabetes often absent in anaesthetized and/or constantly infused diabetic rats, were seen in all conscious servo-controlled diabetic animals. 4. The new regimen enables a more accurate assessment of renal function in experimental diabetes than with previous protocols. It should prove useful in future studies, particularly those assessing the role of anti-diabetic drugs on the kidney. 相似文献
85.
L Stankler D Lloyd RJ Pollitt ES Gray H Thom G Russell 《Archives of disease in childhood》1982,57(3):212-216
A family is described in which 2 siblings born to healthy parents presented with abnormal facies, persistent diarrhoea, and early death. Exhaustive pathological and biochemical investigations failed to find a cause. The scalp hair of both babies had an abnormal amino-acid composition, and presented an appearance that was unique on scanning electron microscopical examination; this fact and the clinical picture probably represents a new syndrome. 相似文献
86.
Christopher B. Pattillo Berenice Venegas Fred J. Donelson Luis Del Valle Linda C. Knight Parkson L.-G. Chong Mohammad F. Kiani 《Pharmaceutical research》2009,26(5):1093-1100
Purpose Radiation upregulates expression of endothelial cell adhesion molecules providing a potential avenue for targeting drugs to
irradiated tissue. Induced upregulation of E-selectin can be used to target immunoliposomes to solid tumors. The effects of
targeting immunoliposomes containing the antivascular drug combretastatin disodium phosphate (CA4P) to irradiated mammary
tumors were investigated in this study.
Methods Mice bearing transplanted MCa-4 mouse mammary tumors were assigned to one of the factorial treatments permuting the administration
of free CA4P, tumor irradiation, CA4P encapsulated liposomes, and CA4P encapsulated immunoliposomes (conjugated with anti-E-selectin).
Single and fractionated dosing of radiation and/or CA4P was evaluated.
Results For single dose treatments the group that received a single dose of radiation plus a single dose of immunoliposomes showed
a significant delay in tumor growth compared to all other treatment groups. Fractionated radiation plus fractionated doses
of immunoliposomes resulted in further tumor growth delay; however, it was not significantly different from other fractionated
dose treatment groups that combined radiation and CA4P.
Conclusions Targeting of antivascular drugs to irradiated tumors via ligand-bearing liposomes results in significant tumor growth delay. This effect can be further potentiated using a fractionated
irradiation dosing schedule combined with fractionated immunoliposome treatments.
CBP and BV made equal contribution to this work. 相似文献
87.
88.
Pineal germinoma: MR imaging 总被引:6,自引:0,他引:6
Magnetic resonance (MR) imaging characteristics of pineal germinomas are described in seven patients imaged with MR and computed tomography (CT). In patients with symptoms of an enlarging process in the quadrigeminal plate cistern, MR imaging was as sensitive as CT scanning in detecting the mass. MR imaging did not detect a normal-sized, calcified neoplastic gland. Germinoma, germinoma with embryonal cell carcinoma elements, and pineoblastoma demonstrated different MR signal characteristics. Although direct coronal and sagittal MR images were useful in defining the relationship of the tumor to the posterior third ventricle, Sylvian aqueduct, and vein of Galen, the ease, rapidity, and sensitivity of CT scanning suggest that CT should remain the modality of choice for initial evaluation and screening of the pineal region, especially in the younger pediatric population, in whom detection of calcification may provide the only clue of an abnormality. 相似文献
89.
90.
H Kaube YE Knight RJ Storer KL Hoskin A May PJ Goadsby 《Cephalalgia : an international journal of headache》1999,19(6):592-597
It remains an open question as to whether cortical spreading depression (CSD) is the pathophysiological correlate of the neurological symptoms in migraine with aura. In the experimental animal, CSD is an electrophysiological phenomenon mainly mediated via NMDA receptors. However, according to case reports in humans, visual aura in migraine can be alleviated by vasodilator substances, such as amyl nitrite and isoprenaline. There is also circumstantial evidence that brainstem nuclei (dorsal raphe nucleus and locus coeruleus) may play a pivotal role in the initiation of aura. In this study, CSD was elicited in alpha-chloralose anesthetized cats by cortical needle stab injury and monitored by means of laser Doppler flowmetry. Topical application of isoprenaline (0.1-1%) and amyl nitrite (0.05%) onto the exposed cortex had no effect on the elicitation or propagation of CSD. Also, after supracollicular transection, subsequent CSDs showed no differences in the speed of propagation and associated flow changes. We conclude from these data that--given CSD probably exists in humans during migraine--spreading neurological deficits during migraine aura are independent of brainstem influence and have a primarily neuronal rather than vascular mechanism of generation. 相似文献