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61.
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Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
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Retinoids influence the pathogenesis of alcohol liver disease (ALD). To analyze the impact of retinoid X receptor alpha (RXRalpha) on ALD, alcohol-induced hepatotoxicity was studied using mice fed ethanol intragastrically for 25 days. Alcohol-induced microvesicular fat around the central vein and drug-induced morphological changes (loss of rough endoplasmic reticulum, pinkish cytoplasm, and enlarged hepatocyte) in the pericentral area were observed in the liver of wild-type mice. In the hepatocyte RXRalpha-deficient mouse liver, alcohol induced fat accumulation, mitosis, acute inflammation, and necrosis. The histology score after alcohol treatment was significantly higher in mutant mice than in wild-type mice. However, drug-induced morphological changes were not apparent in alcohol-treated hepatocyte RXRalpha-deficient mice. Northern analysis showed that the basal and alcohol-induced CYP2B, CYP2A, and CYP3A mRNA levels were lower in hepatocyte RXRalpha-deficient mice than in wild-type mice, which in turn may protect mutant mice from morphological changes. Compared with wild-type mice, hepatocyte RXRalpha-deficient mice have significant lower levels of S-adenosylmethionine and glutathione, which is further reduced after alcohol treatment, and that may account for severe liver injury induced by alcohol. The overall result suggests an important role of RXRalpha in preventing alcohol-induced liver injury.  相似文献   
65.
In this study we tested the hypothesis that photoperiod can modulate steroid access to the brain in a seasonal breeder. To this goal, we compared the passage of exogenous progesterone to the brain of female sheep maintained under short (SD) or long (LD) daylengths. In the first experiment, we studied two groups of ovariectomized females maintained under SD or LD, for three artificial cycles, consisting of bearing a subcutaneous oestradiol implant (E2-treated) and an intravaginal device releasing progesterone (CIDR). During the third cycle, the concentrations of progesterone and of its metabolites 5alpha-dihydroprogesterone and 3alpha-hydroxy-5alpha-pregnan-20-one were measured in the preoptic area (POA). The levels of progesterone in the POA were higher in ewes under LD than under SD while the amounts of metabolites were unchanged. In the second experiment, we compared ovariectomized female sheep equipped with a cannula in the third ventricle to sample the cerebrospinal fluid (CSF) under LD vs. SD. After progesterone (1 mg and 10 mg) was injected into the carotid artery, it was only detectable in the cerebrospinal fluid in sheep under LD. In the third experiment, we compared progesterone concentration in plasma and CSF in two groups of SD vs. LD ovariectomized E2-treated ewes for 2 h under CIDR treatment. Despite similar progesterone plasma concentrations, concentration in the CSF was 2.5 times higher in SD than in LD. Our results suggest a physiological modulation of the passage of progesterone to the brain according to the photoperiod.  相似文献   
66.
The hormonal and metabolic response to the first feed of breast milk was studied in 12 infants at 4-6 hours of age. After the feed there was an increase in blood glucose concentration but no changes in the concentrations of lactate, pyruvate, alanine, or ketone bodies. The feed was followed by an increase in the concentrations of plasma insulin, growth hormone, gastrin, and enteroglucagon, but no change in levels of plasma glucagon or gastric inhibitory peptide. Several hormone systems are functionally active at birth and are stimulated by the first feed of milk.  相似文献   
67.

Background  

Indo-Asians in Canada are at increased risk for cardiovascular diseases. There is a need for cultural and language specific educational materials relating to this risk. During this project we developed and field tested the acceptability of a hypertension public education pamphlet tailored to fit the needs of an at risk local Indo-Asian population, in Calgary, Alberta, Canada.  相似文献   
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In a previous report the effectiveness of intraperitoneal bupivacaine in reducing pain following laparoscopic cholecystectomy was demonstrated. Other methods of pain relief are commonly used but none has been compared following laparoscopic cholecystectomy. In two further studies we have compared the analgesic effect of intraperitoneal bupivacaine against wound infiltration with bupivacaine, and against intraperitoneal bupivacaine with the addition of a non-steroidal anti-inflammatory drug (NSAID) in patients undergoing laparoscopic cholecystectomy. Two consecutive studies were performed. In the first, patients in group 1 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity; patients in group 2 were given 20 ml of 0.25% bupivacaine injected into the trocar wounds. In the second study, patients in group 1 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity; patients in group 2 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity and a diclofenac suppository (100 mg) one hour before surgery. Postoperative pain was assessed with a visual analogue pain scale. There was no difference in pain scores in the two groups in either study. Intraperitoneal bupivacaine is as effective as wound infiltration. The addition of an NSAID makes no difference in the reduction of postoperative pain following laparoscopic cholecystectomy.  相似文献   
70.
The effects of a paramagnetic contrast agent, gadolinium-DTPA (Gd-DTPA), on magnetic resonance (MR) imaging of acute cerebral ischemia was investigated in a feline model of middle cerebral artery occlusion. Imaging was performed both before and after administration of an intravenous dose of 0.2 mmol/kg of Gd-DTPA. The animals were then sacrificed for pathologic correlation. No changes in intensity or relaxation times were noted before or after Gd-DTPA administration in two animals with 2 hours of occlusion. Infarcts were noted before and after contrast enhancement in all six cats with ischemia of greater than 16-hours duration. Gd-DTPA caused significant increase in intensity of infarct but not in that of normal cerebral tissue. Rapid enhancement was visible in infarcts of 16-24 hours, but such enhancement was slower in infarcts of 72-168 hours, presumably owing to slowed inflow caused by increased vasogenic edema in the latter group. Contrast enhancement of acute cerebral ischemic lesions with Gd-DTPA offers no improvement in sensitivity of MR imaging, although the conspicuity of the lesion may be improved. Additionally, contrast media may provide potential temporal and pathophysiological data for better characterization of cerebral ischemia.  相似文献   
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