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81.
82.
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   
83.

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   
84.
In HIV infection, numerous alterations of the hematopoietic system, with frequent cytopenias in peripheral blood and dysplasia of the bone marrow, have been observed. In order to assess the incidence of the myelodysplastic anomalies, 69 bone marrow aspirate smears from 47 patients with group IV HIV infection, as classified by CDC, have been studied. Various degrees of myelodysplastic alterations were found in all cases; however, dysgranulopoiesis was more frequent and more accentuated than other kinds of dyshematopoiesis. Intense vacuolization, especially in the granuloblastic series, was very frequent. It is felt that a bone marrow configuration that is highly indicative of overt AIDS can be sketched. The human immune deficiency virus may be either directly or indirectly responsible for myelodysplastic alterations.  相似文献   
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86.
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   
87.
BACKGROUND: We conducted an external quality assessment of the results obtained in Italian transfusion centre laboratories employing nucleic acid testing (NAT) for detection of HCV RNA in donated blood. STUDY DESIGN: Of 110 transfusions centres in Italy, 101 voluntarily participated. Each laboratory received seven separate shipments of samples for HCV RNA testing by NAT. Each shipment contained 8 plasma samples for a total of 23 negative and 33 positive samples with viral loads ranging from 25 to 1000 IU/mL. RESULTS: Of the 2080 HCV RNA-negative samples, 14 (0.7%) were reported as positive. The highest percent of false-negative results (6.9%) was found on samples from the first shipment with viral loads from 75 to 100 IU/mL. In subsequent shipments, the highest false-negative percentage ranged from 0.6% for samples with viral loads of 170-1000 IU/mL to 3.4% for samples with viral loads of 35-50 IU/mL. A false-negative rate of 4.9% occurred in samples in the sixth shipment with the lowest viral load (25IU/mL). Five (4.9%) centres were identified as having laboratories with low-performance. There were no significant differences among genotypes 1b, 2c and 3a with respect to percent of false-negative results reported. CONCLUSIONS: Overall, the accuracy of NAT observed in this study of Italian transfusion centre laboratories was excellent for all HCV genotypes tested, even for samples with low HCV RNA titres.  相似文献   
88.
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   
89.
Rosenbaum  RC; Johnston  GS 《Radiology》1986,160(1):91-94
The authors studied 54 patients with multisystem trauma, including blunt chest injury, using combined dynamic first-pass and electrocardiographically (ECG) gated radionuclide ventriculography (RNV) to evaluate for posttraumatic myocardial dysfunction. Twenty-six of 54 (48%) patients had abnormalities of ventricular wall motion. The ventricular dysfunction was confined to the right ventricle in 92% of cases. In general, abnormalities consisted of right ventricular dilatation and diffuse hypokinesia, although in seven cases there were localized wall-motion abnormalities. The right ventricular ejection fraction of those patients with wall-motion abnormalities was significantly lower than those with normal studies. Left ventricular ejection fraction did not differ significantly between these groups. ECG changes were not associated with the cardiac dysfunction demonstrated scintigraphically, nor was there a relationship between the number or type of extrathoracic or thoracic injuries demonstrated by RNV. Follow-up studies obtained in 15 cases showed a significant overall improvement in cardiac function by 3 weeks after injury. Combined first-pass and ECG-gated RNV is useful for the identification and follow-up of patients with posttraumatic cardiac dysfunction.  相似文献   
90.
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