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51.
The efficacy of antiretroviral drugs against porcine endogenous retroviruses (PERV) that may be harbored in pig organs intended for transplantation was examined in human cells in vitro. The nucleoside analogs zidovudine and dideoxyinosine were found to effectively inhibit PERV replication.  相似文献   
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BACKGROUND: The cardiac arrest scenario test (CASTest) is a central component of the assessment strategy on the Advanced Life Support Course. The aim of this study was to establish equivalence between the four different CASTest scenarios and investigate the impact of profession, candidate order and course centre on the pass rate. MATERIALS AND METHODS: This was a cluster randomised study. CASTest scenarios were randomly allocated to candidates stratified by course centre. Candidate demographics and performance were recorded on the criterion referenced check list along with the final assessment outcome (pass/fail). Differences in pass rates according scenario; profession, course centre and candidate order were examined by Chi-squared and multiple logistic regression. RESULTS: Two thousand, four hundred and forty-nine assessments from 65 course centres were evaluated. There was no difference in pass rate between scenarios (average pass rate 74.4%). Pass rates according to course centre varied widely (40-93%, P<0.0001) as did professional group (42-100%, P<0.0001). The order that candidates took the test did not influence the pass rate. CONCLUSION: The CASTest assessment scenarios used during ALS testing appear equivalent in terms of difficulty. In contrast, the professional background of the candidate and centre at which the assessment is performed do significantly influence the likelihood of passing the assessment. Further evaluation of the reasons for differences between course centres is required.  相似文献   
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This study examined the dose-dependent effects of Lipopolysaccharide (LPS) on the acoustic startle response and prepulse inhibition (PPI) in male Long-Evans rats. LPS is known to stimulate the innate immune system and result in behavior modifications referred to as "sickness behaviors". The purpose of this study was to assess the ability of LPS to modulate sensorimotor reflexes (Startle-Only trials) and/or sensory processing (PPI trials). Rats were injected intraperitoneally with LPS (50, 100 or 200 microg/kg LPS, n=9/group) or saline vehicle (n=14) on 2 test days 72 h apart. Subjects were placed in a familiar startle box apparatus where startle response magnitudes were recorded following 115 dB Startle-Only trials and PPI trials (with prepulses at +3, +6 and +12 dB above background noise). Analysis of Startle-Only trials indicated a significant dose-dependent effect of LPS on Test Day 1. The 200 microg/kg LPS group exhibited significantly reduced startle response magnitude relative to all other treatments. On the PPI trials no LPS groups displayed significantly different performance from vehicle controls. Also, DayxDrug interactions for both Startle-Only and PPI trial types indicated behavioral tolerance to LPS. LPS reduced the acoustic startle response in a dose-dependent manner on Test Day 1. From the PPI data, it is evident that all treatment groups elicited near-normal inhibition levels indicating adequate sensory function. In combination, the results suggest that the range of sickness behaviors following LPS-administration to adult rats includes decreased non-voluntary motor activity as reflected by reduced startle magnitude.  相似文献   
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Background:

Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.

Materials and Methods:

Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.

Results:

All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.

Conclusion:

Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group.  相似文献   
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Background:

Compartment syndrome is a potentially devastating condition. Increased intracompartmental pressure has been incriminated as the primary pathogenic factor in compartment syndrome. The purpose of this prospective study was to monitor the anterior compartmental pressure and differential pressure to minimize the incidence of acute compartment syndrome.

Materials and Methods:

Seventy-five consecutive cases of closed fractures of leg presenting within six hours of injury were taken for measurement of anterior compartment pressure at the level of fracture and at 5 cm and 10 cm away from the fracture site, using the Whitesides'' infusion technique. A differential pressure of less than 30 mm Hg was taken as the criterion for diagnosis of compartment syndrome.

Results:

Two patients (2.67%) developed acute compartment syndrome. The mean anterior compartment pressures were highest at the level of the fracture and went on decreasing as we went away from the fracture site, which was found to be statistically significant (P < 0.001).

Conclusion:

Compartment pressure measurement is the most reliable and objective method for early diagnosis of compartment syndrome. Whitesides'' infusion technique is a relatively easy and inexpensive method to come to a diagnosis of compartment syndrome in a developing country like India. Differential pressure is more reliable than absolute pressure in predicting the development of an impending compartment syndrome.  相似文献   
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