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This study compares the efficacy of omeprazole and ranitidine at reducing gastric secretion in obstetric patients. Sixty-five women scheduled to undergo elective Caesarean section under general anaesthesia were randomly allocated to receive either omeprazole 40 mg or ranitidine 150 mg orally at 2200 hours the night before and at 0600 hours on the morning of surgery. Intragastric pH and volume were measured immediately after induction of anaesthesia and on completion of surgery. All patients had gastric aspirates less than 25 ml. None of the omeprazole group had an aspirate of pH less than 3.5. Six patients (19%) in the ranitidine group had aspirates of pH less than 3.5, a significant difference from the omeprazole group (p less than 0.05). Of these six, two (6%) had aspirates of pH less than 2.5. Hence this study showed that omeprazole was more effective and consistent than ranitidine at maintaining gastric pH greater than 3.5.  相似文献   
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Similar to the response to central hypervolemic conditions on Earth, the shift of blood volume from the legs to the upper part of the body in astronauts entering micro-gravity should, in accordance with the Henry-Gauer mechanism, mediate diuresis and natriuresis. However, fluid balance and kidney function experiments during various space missions resulted in the surprising observation that the responses qualitatively differ from those observed during simulations of hypervolemia on Earth. There is some evidence that the attenuated responses of the kidney while entering weightlessness, and also later during space flight, may be caused by augmented fluid distribution to extravascular compartments compared to conditions on Earth. A functional decoupling of the kidney may also contribute to the observation that renal responses during exposure to micro-gravity are consistently weaker than those during simulation experiments before space flight. Deficits in body mass after landing have always been interpreted as an indication of absolute fluid loss early during space missions. However, recent data suggest that body mass changes during space flight are rather the consequences of hypocaloric nutrition and can be overcome by improved nutrition schemes. Finally, sodium-retaining humoral systems are activated during space flight and may contribute to a new steady-state of metabolic balances with a pronounced increase in body sodium compared to respective conditions on Earth. A revision of the classical "micro-gravity fluid shift" scheme is required.  相似文献   
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BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
6.

Objective

The aim of this study was to evaluate the effect of multiple layers of an infection control barrier on the micro-hardness of a composite resin.

Material and Methods

One, two, four, and eight layers of an infection control barrier were used to cover the light guides of a high-power light emitting diode (LED) light curing unit (LCU) and a low-power halogen LCU. The composite specimens were photopolymerized with the LCUs and the barriers, and the micro-hardness of the upper and lower surfaces was measured (n=10). The hardness ratio was calculated by dividing the bottom surface hardness of the experimental groups by the irradiated surface hardness of the control groups. The data was analyzed by two-way ANOVA and Tukey''s HSD test.

Results

The micro-hardness of the composite specimens photopolymerized with the LED LCU decreased significantly in the four- and eight-layer groups of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. The hardness ratio of the composite specimens was <80% in the eight-layer group. The micro-hardness of the composite specimens photopolymerized with the halogen LCU decreased significantly in the eight-layer group of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. However, the hardness ratios of all the composite specimens photopolymerized with barriers were <80%.

Conclusions

The two-layer infection control barrier could be used on high-power LCUs without decreasing the surface hardness of the composite resin. However, when using an infection control barrier on the low-power LCUs, attention should be paid so as not to sacrifice the polymerization efficiency.  相似文献   
7.
Norsk P  Christensen NJ  Bie P  Gabrielsen A  Heer M  Drummer C 《Lancet》2000,356(9241):1577-1578
Urine output in astronauts following ingestion of an oral water load was low in space on the Russian space station Mir and less than during simulation by 6 degrees head-down bed rest. This surprising observation shows that the effects of gravity and weightlessness on fluid volume regulation are not well understood and that the head-down bed-rest model does not simulate the effects of weightlessness on renal water handling.  相似文献   
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Summary.  The complete nucleotide sequence of the gammaherpesvirus equine herpesvirus 5 (EHV5) glycoprotein B (gB) was determined and the deduced amino acid sequence compared with that of the second equine gammaherpesvirus EHV2. EHV5 gB is an 870 amino acid protein and is 79% similar and 66% identical with EHV2 gB at the amino acid level. EHV5 gB like EHV2 gB is a disulphide linked heterodimer with subunits of 92 and 68 kDa. EHV5 gB is an integral membrane glycoprotein containing only N-linked oligosaccharides and contains a putative endoproteolytic cleavages site at amino acids 422–485. The EHV5 gB amino acid sequence showed greatest homology with other members of the Rhadinovirus genus of the subfamily Gammaherpesvirinae. Alignment of EHV5 gB sequence with the gB sequence of seven other gammaherpesviruses showed conservation of 10 cysteine residues as well as conservation of three predicted sites of N-linked glycosylation; the highest degree of conservation of the predicted sites of N-linked glycosylation was observed between EHV5 and the other members of the Rhadinovirus genus. Phylogenetic analysis confirmed EHV2 and EHV5 were most closely related to each other and equally distant from other members of the Rhadinovirus genus included in the analysis. Accepted September 7, 1998 Received March 5, 1998  相似文献   
10.
BACKGROUND: The role of neutralizing antibody (NAb) in determining response to antiviral therapy has not been established. OBJECTIVE: In this study we have analysed the kinetic's of the NAb response in patients with chronic hepatitis C who received antiviral therapy. STUDY DESIGN: Seventeen patients infected with genotype 1, 2a/c or 3a hepatitis C virus (HCV) were enrolled, eight with a sustained virological response (SVR), five non-responders and four relapsers. RESULTS: The mean NAb titre required to neutralize 50% of the E1E2-pp in patients who achieved an SVR (294+/-S.D. 51), in relapsers (246+/-S.D. 61.7) and non-responders (286+/-S.D. 80.95) did not differ significantly between the patient groups and did not alter during the course of treatment (P>0.01). Genetic variation present before antiviral therapy was analysed by single strand conformation polymorphism (SSCP) and failed to demonstrate a significant difference in the mean number of amplified E1E2 DNA fragments from the serum of patients who achieved an SVR (3.15+/-S.D. 1.53), relapsers (2.8+/-S.D. 1.32) or non-responders (3.69+/-S.D. 1.75). The baseline serum HCV viral loads were also not significantly different between patients who achieved an SVR (1.4 x 10(6) copies/ml; +/-S.D. 2.4 x 10(6)), relapsers (1.3 x 10(7) copies/ml; +/-S.D. 2.4 x 10(7)) and non-responders (1.5 x 10(6) copies/ml; +/-S.D. 1.1 x 10(6)). CONCLUSION: We have shown that neutralizing anti-HCVpp antibody is not associated with response to antiviral therapy. In addition, there was no correlation between baseline virological load, circulating viral quasi-species, NAb titres and final response to treatment.  相似文献   
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