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81.
Observation units for children in an Emergency Department setting can serve to improve the quality of medical care provided as well as reduce overall costs; however, they must be properly organized with careful consideration for the needs of children. Policies must be written specifying who is in charge as well as who can be accepted into these units and for how long. Procedures regarding documentation and sign-out must be formulated. These units must be well staffed and fully equipped, and they should be pleasant places for the children to stay; otherwise, what might begin as assets can quickly become disorganized and potentially dangerous liabilities. 相似文献
82.
This report describes a unique case of biliary and portal obstruction by a massive celiac artery aneurysm. Severe portal hypertension with extensive retroperitoneal varices and a perforated gallbladder complicated the surgical management. A survey of the literature emphasized the novelty of this case. 相似文献
83.
Despite the wide clinical use of lithium in the treatment of manic depressive illness there is no adequate explanation for its mechanism of action. In the light of lithium's suggestive effects on the second messenger system in the brain, we studied the effects of chronic dietary lithium treatment (achieving blood levels in the therapeutic range) on protein phosphorylation in different areas of rat brain. An increase in the phosphorylation of a 64-kDa membrane-associated protein was evident in the lithium-treated rats compared to controls. This increase was observed only under basal phosphorylating conditions and was abolished when the phosphorylation was performed in the presence of Ca2+ or Ca2+ and calmodulin. The possibility that this 64-kDa protein affected by lithium is the beta-subunit of the calmodulin-dependent protein kinase or a different protein which co-migrates with it is discussed. 相似文献
84.
85.
86.
G Klein 《Blood pressure》1998,7(5-6):308-312
This study compared the antihypertensive efficacy and tolerability of a combination tablet containing the vascular-selective calcium antagonist felodipine and the beta1-selective adrenergic antagonist metoprolol, with a combination tablet of captopril-hydrochlorothiazide in a randomized, double-blind trial involving 109 patients with mild to moderate hypertension. After 2 weeks on placebo, patients with a supine diastolic blood pressure of 95-115 mm Hg were randomized to felodipine-metoprolol, 5/50 mg o.d. (Logimax) or captopril-hydrochlorothiazide, 25/25 mg o.d. (Capozide). After a further 4 weeks, there was a mandatory dose increase to felodipine-metoprolol 10/100 mg o.d., and captopril-hydrochlorothiazide, 50/25 mg o.d., and treatment then continued for a another 4 weeks. At the end of the study, felodipine-metoprolol reduced supine blood pressure significantly more than captopril-hydrochlorothiazide. The mean differences in change in supine systolic and diastolic blood pressure between treatments after 8 weeks were 5.2 and 3.4 mm Hg, respectively, in favour of felodipine-metoprolol (p<0.05). Standing blood pressure also showed trends in favour of felodipine-metoprolol. The proportion of responders was similar in both groups. Both treatments were well tolerated. Two patients treated with felodipine-metoprolol and 5 with captopril-hydrochlorothiazide discontinued treatment due to adverse events. Felodipine-metoprolol combination reduced supine blood pressure significantly more than captopril-hydrochlorothiazide with maintained tolerability. 相似文献
87.
P M Colombani F G Cigarroa K Schwarz B Wise W E Maley A S Klein 《Annals of surgery》1996,223(6):658-664
OBJECTIVE: The authors report on experience with liver transplantation for infants younger than 1 year of age. SUMMARY BACKGROUND DATA: Over the last 15 years, orthotopic liver transplant has become the only lifesaving procedure available for infants with end-stage liver disease. Many transplant centers initially required infants to reach a specific weight or age to minimize morbidity and mortality. Size-appropriate infant donors also were uncommon. As a result, many children, in the first few years of life, died of their disease. The availability of reduced-size cadaveric and living-related liver transplants has offered the ability to transplant the young infant with liver failure. METHODS: The authors instituted a program to aggressively transplant infants with liver failure in the first year of life using both cadaveric and living-related liver donors. RESULTS: Between June 1991 and January 1995, 13 infants were transplanted for rapidly progressive liver failure. Infant age ranged from 4 to 11 months (mean, 7.5 months). The cause of liver failure included biliary atresia (11), alpha 1-antitrypsin deficiency (1), and liver failure secondary to echovirus 7 (1). The United Network for Organ Sharing status at the time of transplant ranged from status 4, intensive care unit bound (4 patients); status 3, hospitalized (4 patients); or status 2, failing at home (5 patients). Six patients (46%) received cadaveric whole organ (2) or segmental transplants (4). Seven patients (54%) received left lateral segment living-related transplants from parental donors. After operation, patients received cyclosporine or FK506-based immunosuppression. Three patients (23%) required four retransplants (two cadaveric for primary nonfunction; one living-related for graft thrombosis in the face of fungal infection and bile leak). Postoperative complications included primary nonfunction (15%), rejection (85%), graft vascular thrombosis (15%, two of three revascularized successfully), bacterial and fungal infections (77%), and viral infections (46%). Epstein-Barr virus-associated lymphoproliferative developed in two patients (15%). Intestinal perforation requiring reoperation developed in two patients (15%). Bile leaks requiring reoperation or transhepatic stinting or both developed in three patients (23%). Two patients died in the perioperative period (< 1 month) from a combination of primary nonfunction or graft thrombosis and sepsis. Overall survival was 85%, ranging from 11.0 months to 4.5 years. CONCLUSIONS: Orthotopic liver transplantation in infants younger than 1 year of age poses significant challenges from technical and infectious complications. Despite these barriers, overall patient survival is comparable to that of older children and adults. 相似文献
88.
Objective. Bone infarction (BI) of the calcaneus is an uncommon entity which has received little mention in the recent literature. In
this paper, we review the MR images of six calcanei with BI, which demonstrate a pattern of presentation that may explain
the etiology of BI at this unusual location. Design. A retrospective review was performed of the transcribed reports of the foot or ankle MR examinations at our institution.
MR images of examinations with any marrow signal abnormality were reviewed for presence of BI and its distribution. Patients. Based on MRI criteria, four patients had calcaneal BI (none biopsy proven); they ranged in age from 37 to 51 years old. Two
patients were diagnosed with systemic lupus erythematosus, one with fibrositis, and another with polymyositis. All were treated
with corticosteroids. Results. Six calcanei (in four patients) contained a region of calcaneal BI. In five of the six, the lesions were entirely or predominantly
located in the posterior half of the calcaneus. Conclusion. Two theories are proposed which may explain why BI predominantly occurs in the posterior half of the calcaneus. First, the
convergence of the recurrent intraosseous calcaneal vessels may occasionally produce the equivalent of a single dominant vessel
that is more prone to vascular accidents. Secondly, the region between the recurrent and the epiphyseal vessels may act as
a watershed zone, increasing its susceptibility to ischemia. 相似文献
89.
90.
Transcutaneous oximetry measurements were performed on 25 limbs in 25 patients with clinical and radiographic nonunion, and compared with data obtained from patients with healed tibia fractures and a control group of nonfractured extremities. A technique of "stress testing" vascular inflow patterns by temporary occlusion of arterial inflow was utilized to accentuate differences in perfusion not apparent at rest between normal limbs and those with inflow impairment. Changes in postocclusive hyperemic response were monitored by changes in transcutaneous oxygen detected by sensors placed over the dorsum of the foot, at the fracture site, over the anterior compartment, and at the chest. No statistically significant differences were found between the control group and the group of united tibia fractures. Analysis of results using the unpaired Student's t-test demonstrated statistically significant differences between the control and nonunion groups at each limb site tested (p less than 0.05). The prolonged oxygen recovery time values found in more than half the limbs with nonunion are consistent with the presence of impaired oxygenation following physiologic stress. The impairment of oxygenation appears to be on a perfusion basis and reflects the limited capacity of many limbs with tibial nonunion to respond to experimental ischemia with immediate compensatory hyperemia. Clinical relevance: This technique is a feasible method for serially assessing the regional oxygenation of a limb, and substantiates ischemia as a possible factor in the genesis of tibial nonunion. 相似文献