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31.
32.
Ingunn Bj?rnsdóttir Thomas Ray Einarson Lárus Steintór Guemundsson Rannveig Alma Einarsdóttir 《Pharmacy World & Science》2007,29(6):577-583
Aim To determine the efficacy of diphenhydramine against cough due to respiratory infection or irritation in patients/subjects
without comorbidities.
Method Two reviewers independently identified English language studies, searching on: clinical trials, randomized, diphenhydramine
(OR dimenhydrinate), antitussive agents, cough (combine using AND). Sources were: Medline (1966–2005), Embase (1980–2005),
Cochrane and references from retrieved articles. Two other reviewers, blinded to study origin selected studies, inclusion
criteria being: diphenhydramine monotherapy against placebo, double-blinded, randomized, clinical trial, intention-to-treat,
dropout information. The blinded reviewers evaluated the selected studies on a quality scale.
Results Eleven articles were identified, 7 were rejected (4 not placebo controlled, 2 had no diphenhydramine, 1 not blinded), leaving
4 articles, that were included in the evaluation and scored 20, 21, 25 and 26 out of a maximum of 32. In these selected studies,
a total of 162 people were examined, 65 on diphenhydramine, 63 on placebo and 34 in a crossover setting. There was a total
of 13 dropouts. The crossover studies demonstrated significant effect; 27–56% reduction in 20 healthy volunteers and 21–26%
reduction in 13 patients (originally 14, one outlier left out), whereas the active versus placebo studies did not.
Conclusion In spite of the 60 years that the substance has been on the market, only few studies have properly evaluated the effect of
diphenhydramine against cough. Presumptions about efficacy of diphenhydramine against cough in humans are not univocally substantiated
in literature. 相似文献
33.
Ivar Rønnestad Einar Thorsen Kåre Segadal Arvid Hope 《European journal of applied physiology》1994,69(1):32-35
In diving, pulmonary mechanical function is limited by the increased density of the gas breathed. Breathing cold and dry gas may cause an additional increase in airways resistance. We have measured forced vital capacity, forced expired volume in 1 s (FEV1) and forced midexpiratory flow rate (FEF25%–75%) before and after breathing dry or humid gas at 29–32°C during a standardized exercise intensity on a cycle ergometer at an ambient pressure of 3.7 MPa. The atmosphere was a helium and oxygen mixture with a density of 6.8 kg · m–3. Six professional saturation divers aged 26–37 years participated in the study. There were no significant differences in convective respiratory heat loss between the exposures. The mean evaporative heat loss was 67 W (range 59–89) breathing dry gas and 37 W (range 32–43) breathing humid gas, corresponding to water losses of 1.7 g · min–1 (range 1.5–2.2) and 0.9 g · min–1 (range 0.8–1.1), respectively. There was a significant reduction in FEV1 of 4.6 (SD 3.6)% (P<0.05), and in FEF25%–75% of 5.8 (SD 4.7)% (P<0.05) after breathing dry gas. There were no changes after breathing humid gas. By warming and humidifying the gas breathed in deep saturation diving bronchoconstriction may be prevented. 相似文献
34.
Björn-Christian Link Emre F. Yekebas Dean Bogoevski Asad Kutup Gerhard Adam Jakob R. Izbicki Gerrit Krupski 《Journal of gastrointestinal surgery》2007,11(2):166-170
Symptomatic biliary leakage following major upper abdominal surgery is a severe complication resulting in increased morbidity
and mortality. Treatment options usually include either endoscopic intervention or surgical revision. These options may be
burdened by a high perioperative risk for the patient (e.g., patients with severe disease) or simply may not be possible (e.g.,
nonpreserved gastroduodenal passage). In the past, percutaneous transhepatic cholangiodrainage did only seem to be a viable
option for patients with dilated bile ducts. Here, we present our experience in a consecutive series of patients with symptomatic
biliary leakage following major upper abdominal surgery and without dilation of the biliary system that underwent percutaneous
transhepatic cholangiodrainage. Percutaneous transhepatic cholangiodrainage was feasible in 15 of 18 patients (83.3%). The
procedure was technically not possible in three patients (16.7%). In 10 of the 15 patients (66.6%) with feasible percutaneous
transhepatic cholangiodrainage, biliary leakage was definitely controlled without the need for surgical revision. Depending
on the experience with the interventional procedure, percutaneous transhepatic cholangiodrainage should be considered as an
alternative for treatment of symptomatic biliary leakage instead of immediate reoperation.
Presented at the Digestive Disease Week 2005 (DDW), Chicago, IL, May 14–19, 2005 (poster presentation). 相似文献
35.
36.
The effect of fraction time in intensity modulated radiotherapy: theoretical and experimental evaluation of an optimisation problem. 总被引:3,自引:0,他引:3
Xiangkui Mu Per-Olov L?froth Mikael Karlsson Bj?rn Zackrisson 《Radiotherapy and oncology》2003,68(2):181-187
BACKGROUND AND PURPOSE: In intensity modulated radiotherapy (IMRT), the complexity and the number of treatment fields have expanded. This may imply that the delivery time for each fraction becomes prolonged. In a number of IMRT techniques used in the clinic, the delivery time per fraction is usually 10-15 min, sometimes more than 15 min. In studies on human skin, prolonged delivery time is shown to cause significant reduction of radiation effects compared with acute irradiation. In this paper the effect of changes in fraction delivery time was studied by in vitro irradiation of mammalian cells. MATERIAL AND METHODS: Chinese hamster fibroblasts (V79-379-A) were used for simulating clinical situations. Most experiments were performed with 2Gy/fraction with 4-h intervals in 40-60 replicates. Each fraction was divided into different subfractions, simulating the delivery of a complicated treatment. The effect of changing the delivery time for each fraction was studied. Parameters for the cell survival curve and repair kinetics were determined experimentally. The same methods were also used for large fraction sizes (8Gy). The validity of the most widely used models in the literature, all derived from linear-quadratic formalism, were tested against the experimental results. RESULTS: The effect of prolonging the fraction time for 2-Gy fractions was underestimated by the biological models. The experiments showed that 10-min prolonged delivery time gave a ratio between surviving fractions at 2Gy (S-ratio) of 1.054 with a 95% confidence interval (CI) 1.030-1.080, while the models predicted 1.007 and 1.009. Extending the fraction time to 20 min gave an S-ratio of 1.063 with CI of 1.045-1.080, while the models predicted 1.012 and 1.014. For 8-Gy fractions, there was a good agreement between predications and experimental results. The ratio between surviving fractions at 8Gy is 1.370 with CI of 1.300-1.440, while the models predicated 1.37 and 1.35. CONCLUSIONS: The effect of prolonging fraction time at conventional dose/fraction is underestimated by biological models. Prolonging the fraction time will spare tissues with a fast DNA repair. There is a risk for sparing tumours. This should be considered when IMRT technique is implemented in the clinic. 相似文献
37.
Leslie K Jacobsen Kenneth R Pugh Robert T Constable Michael Westerveld W Einar Mencl 《Neuropsychopharmacology》2007,61(1):31-40
BACKGROUND: Cannabis remains the most widely used illicit substance by adolescents and is typically consumed by this population in the context of ongoing tobacco use. Human studies have shown that both cannabis and tobacco exert effects on cognitive function; however, little is known about possible interacting effects of these drugs on brain function and cognition during adolescent development. METHODS: Verbal learning and memory were assessed in 20 adolescent users of tobacco and cannabis and 25 adolescent tobacco users with minimal history of cannabis use. Functional magnetic resonance imaging was used to examine brain function and functional connectivity while a subset of these subjects performed a verbal working memory task. RESULTS: Delayed recall of verbal stimuli deteriorated during nicotine withdrawal among cannabis users but not among comparison subjects. During high verbal working memory load, nicotine withdrawal selectively increased task-related activation of posterior cortical regions and was associated with disruption of frontoparietal connectivity in adolescent cannabis users relative to comparison subjects. CONCLUSIONS: These observations suggest that cannabis use during adolescent development may disrupt neurocircuitry supporting verbal memory formation and that deficits associated with disruption of these neurocircuits are unmasked during nicotine withdrawal. 相似文献
38.
Kjetil G. Brurberg Ilana C. Benjaminsen Liv M.R. Dørum Einar K. Rofstad 《Magnetic resonance in medicine》2007,58(3):473-481
Temporal heterogeneity in blood perfusion is a common phenomenon in tumors, but data characterizing the nature of the blood flow fluctuations are sparse. This study investigated the occurrence of blood flow fluctuations in A-07 melanoma xenografts by using gadopentetate dimeglumine (Gd-DTPA)-based dynamic contrast-enhanced MRI (DCE-MRI). Each tumor was subjected to two DCE-MRI acquisitions separated by 1 hour. The data were processed by Kety analysis and resulted in two E.F images (E is the initial extraction fraction of Gd-DTPA and F is the perfusion) and two lambda images (lambda is the partition coefficient of Gd-DTPA) for each tumor. The E . F images were used to determine the changes in blood perfusion arising in the time between the two imaging sequences. The lambda images were used to control the reproducibility of the experimental procedure. The study showed that DCE-MRI with subsequent Kety analysis is a useful method for detection of blood flow fluctuations in A-07 tumors, and strongly suggested that the peripheral regions of A-07 tumors are more exposed to temporal changes in blood perfusion than are the central regions. 相似文献
39.
Daniel Klase Stefan Gottschalk Erich Reusche Christian Hagel Einar Goebel Volker Tronnier Alf Giese 《Child's nervous system》2007,23(8):907-912
CASE REPORT: The reported female patient underwent sub-total resection of an intra-medullary cervicothoracic astrocytoma classified as WHO grade II in 1984 at the age of 18 months and received local irradiation. In 1989, a local recurrence was diagnosed and a partial resection was performed. Sixteen years later, a small recurrent cervicothoracic tumour was found and spinal seeding to the equine nerve roots and the left cerebellar cortex was apparent on MRI. The patient was implanted with a ventriculoperitoneal shunt for a pseudo-tumour cerebri producing papilloedema, which eventually lead to amaurosis. After an extended biopsy, the invasive lumbosacral tumour was classified as glioblastoma multiforme. Two months later, the patient died after rapid progression of the caudal cranial nerve dysfunction. DISCUSSION AND CONCLUSION: Anaplastic progression and dissemination of spinal astrocytomas even two decades after initial diagnosis and treatment are rare. Therapies and diagnostic follow-up strategies are discussed. 相似文献
40.
Arne T. Hstmark Einar Lystad Einar Jebens Jan Skramstad Paul Fryen 《Basic & clinical pharmacology & toxicology》1998,83(1):29-35
Abstract: Chlorinated fatty acids represent a major fraction of extractable, organically bound chlorine in fish. After dietary intake such fatty acids may be transferred from the mother to the foetus through the placenta, and via breast milk to the child. In the present work we have studied the effect of chlorinated oleic acid on the growth of three widely differing types of cells in culture. Chlorinated oleic acid inhibited growth of Human Microvascular Endothelial Cells (HMVEC), Immortilized Human Kidney Epithelial (IHKE) cells, and human Hepatoma cells (HepG2). The order of potency was: HMVEC > IHKE > HepG2. Vitamin E counteracted the inhibitory effect of chlorinated oleic acid on HepG2 cells, but did not significantly affect the fatty acid effect on HMVEC or IHKE. Defatted serum albumin stimulated the growth of HMVEC and IHKE. With HMVEC there was no major interaction between the effect of albumin and chlorinated oleic acid on cell growth. In contrast, with IHKE albumin at low concentration abolished the growth inhibiting effect of chlorinated oleic acid and appreciably counteracted growth inhibition by the fatty acid of HepG2 . We conclude that the growth modulation by chlorinated oleic acid and its interaction with vitamin E and albumin are cell specific. 相似文献