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In a randomized cross-over design, 7 patients with winter depression were treated with a week of a bright (1700 lx) dawn simulation (0400 to 0600) and a week of standard bright (1700 lx) morning (0600 to 0800) light therapy. The Hamilton Rating Scale for Depression scores decreased significantly for the standard light therapy (18.9 to 6.6) but not for the bright dawn therapy (18.0 to 11.3). Early morning awakening was a frequent side effect with the bright dawn simulation. Although dawn simulation at a lower illuminance may be an effective treatment, the bright dawn used in this study showed only a nonsignificant trend to lower depression ratings. The illuminance of dawn simulation should be adjusted to minimize side effects. 相似文献
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GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
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The effect of Iliparcil, a new orally active beta-D-xyloside venous antithrombotic, was studied on the rethrombosis following thrombolytic therapy in rats, using a modified Umetsu model. The drug was administered by oral route prior to thrombolytic therapy, which consisted of administering a combination of heparin and urokinase (H/U) at 37.5 and 70,000 IU/kg, respectively. Time to reocclusion increased from 3.9 min with saline to 10.5 min following H/U injection. When Iliparcil (30 mg/kg, oral route) was administered 4 h before H/U injection, the time to reocclusion was increased by 250% compared with H/U alone (p < 0.001). Similarly, dermatan sulfate (DS), administered intravenously (3 mg/kg) 5 min before thrombus induction, also increased the time to reocclusion (300% compared with H/U alone; p < 0.001). It was also shown that times to reocclusion following Iliparcil or DS treatments were still increased even when heparin dosage was decreased. These results suggest that an antithrombotic product derived from the beta-D-xyloside family could be advantageously used in combination with thrombolytic treatment instead of heparin, which causes complications and side effects. 相似文献
6.
Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
7.
The preceding discussion has profiled the three different types of knee braces available on today's market. It has attempted to discuss the controversies surrounding these braces and to analyze the scientific data presented to date. Prophylactic braces have been shown to be ineffective in preventing knee injuries in their present-day design. Evidence has also shown that their use may even lead to increased knee injuries. On the other hand, rehabilitative braces do serve a useful purpose in regard to the operative and nonoperative treatment of ligamentous knee injuries. With their use in the application and control of joint motion, they are an important addition to the surgeon's armamentarium. One must keep in mind, however, that these braces provide little static anterior/posterior control and the hinge settings may not actually reflect true joint motion. Functional knee braces may play a role in the treatment of patients with pathologic laxity owing to an injury of the ACL. Combined with an adequate rehabilitation program and activity modification, these braces do limit excessive anterior tibial translation under low-loading conditions. However, under conditions of high loading these braces provide little or no resistance to anterior translation. Therefore, in most sporting activities, their efficacy is questionable. Knee bracing continues to be a complex and controversial topic in the field of orthopaedic surgery. The answers for the design of the "ideal" brace are being continually worked out and the need for more detailed, well-controlled studies continues to be great.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献
10.
Energy cost and running mechanics during a treadmill run to voluntary exhaustion in humans 总被引:1,自引:0,他引:1
R. Candau A. Belli G. Y. Millet D. Georges B. Barbier J. D. Rouillon 《European journal of applied physiology》1998,77(6):479-485
The aim of the present study was to examine the physiological and mechanical factors which may be concerned in the increase in energy cost during running in a fatigued state. A group of 15 trained triathletes ran on a treadmill at velocities corresponding to their personal records over 3000m?[mean 4.53 (SD 0.28) m?·?s?1] until they felt exhausted. The energy cost of running (C R) was quantified from the net O2 uptake and the elevation of blood lactate concentration. Gas exchange was measured over 1?min firstly during the 3rd–4th?min and secondly during the last minute of the run. Blood samples were collected before and after the completion of the run. Mechanical changes of the centre of mass were quantified using a kinematic arm. A significant mean increase [6.9 (SD 3.5)%, P?0.001] in C R from a mean of 4.4 (SD 0.4) J?·?kg?1?·?m?1 to a mean of 4.7 (SD 0.4) J?·?kg?1?·?m?1 was observed. The increase in the O2 demand of the respiratory muscles estimated from the increase in ventilation accounted for a considerable proportion [mean 25.2 (SD 10.4)%] of the increase in CR. A mean increase [17.0 (SD 26.0)%, P?0.05] in the mechanical cost (C M) from a mean of 2.36 (SD 0.23) J?·?kg?1?·?m?1 to a mean of 2.74 (SD 0.55) J?·?kg?1?·?m?1 was also noted. A significant correlation was found between C R and C M in the non-fatigued state (r?=?0.68, P?0.01), but not in the fatigued state (r?=?0.25, NS). Furthermore, no correlations were found between the changes (from non-fatigued to fatigued state) in C R and the changes in C M suggesting that the increase in C R is not solely dependent on the external work done per unit of distance. Since step frequency decreased slightly in the fatigued state, the internal work would have tended to decrease slightly which would not be compatible with an increase in C R. A stepwise regressions showed that the changes in C R were linked (r?=?0.77, P?0.01) to the changes in the variability of step frequency and in the variability of potential cost suggesting that a large proportion of the increase in C R was due to an increase in the step variability. The underlying mechanisms of the relationship between C R and step variability remains unclear. 相似文献