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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Nervensch?digungen als Begleitverletzungen bei Monteggia-Frakturen sind selten und betreffen meistens den N. radialis. üblicherweise
kommt es bei frischen Frakturen zu einer spontanen neurologischen Remission, nachdem der Radiuskopf wieder reponiert wurde.
Im vorliegenden Fall erlitt ein heute 33-j?hriger Mann eine Parese des N. interosseus posterior 27 Jahre nach einer Monteggia-Fraktur,
wobei der Radiuskopf in luxierter Stellung verblieb. Nach einem Bagatelltrauma am Handgelenk beim Federballspielen kam es
zu einer L?hmung der Handgelenk- und Fingerstreckmuskulatur. Eine konservative Behandlung mittels intensiver Physiotherapie
blieb auch nach 4 Monaten erfolglos. Daraufhin wurde der Nerv exploriert. Der Profundusast zeigte sich dabei narbig adh?rent
im Bereich einer beengenden und verdickten Frohse-Arkade. Anschlie?end erfolgte eine Narbenl?sung sowie Spaltung der Arkade,
der Radiuskopf wurde im ursprünglichen verrenkten Zustand belassen. Eine v?llige Erholung des l?dierten Nerven war 9 Monate
postoperativ erreicht. 相似文献
993.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben. 相似文献
994.
王伏虎 《南京医科大学学报(英文版)》2002,16(2):49-64
Stroke is a debilitating disease that affects millions each year.While in many cases cerebral ischemic in jury can be limited by effectivw resuscitation or thrombolytic treatment,the injured neurons wither in a process known as delayed neuronal death(DND).Mounting evidence indicates that DND is not simply necrosis played out in slow motion but apoptosis is triggered.Of particular interest are two groups of signal proteins that participate in apoptosis-cyclin dependent kinases(CDKs) and p53-among a myriad of signaling events after an ischemic insult.Recent investigations have shown that CDKs,a family of enzymes initially known for their role in cell cycle regulation,are activated in injured neurons in DND.As for p53,new reports suggest that its up-regulation may represent a failed attempt to rescue in jured neurons,although its up-regulation was previously considered an indication of apoptosis.These observations thus rekindle an old quest to identify new neuroprotective targets to minimize the stroke damage.In this review,the author will examine the evidence that indicates the participation of CDKs and p53 in DND and then introduce pre-clinical data to explore CDK inhibition as a potential neuroprotective target.Finally,using CDK inhibition as an example,this paper will discuss the pertinent criteria for a viable neuroprotective strategy for ischemic in jury. 相似文献
995.
U. Ravens Michael O. Flüß Q. Li Herbert M. Himmel Erich Wettwer Michael Klockow Inge Lues 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(6):733-742
The thiadiazinone derivative [+]-EMD 60263 ((+)-5-(1-(α-ethylimino-3,4-dimethoxybenzyl)-1,2,3,4- tetrahydroquinoline-6-yl)-6-methyl-3,6-dihydro-2H-1,3,4
-thiadiazine-2-on) is a Ca2+-sensitizing agent with only minor phosphodiesterase inhibitory activity. Our aim was to characterize the inotropic and electrophysiological
effects of [+]-EMD 60263 and its enantiomer [-]-EMD 60264 in several cardiac muscle preparations. The Ca2+-sensitizing activity resided in the [+]-enantiomer only. [+]-EMD 60263 (3 μM) shifted the EC50 of Ca2+ for contractile activation of skinned fibers of pig heart from 2.41 μM to 0.73 μM, whereas [-]-EMD 60264 (30 μM) was ineffective.
In Langendorff-perfused guinea pig hearts, [+]-EMD 60263 and [-]-EMD 60264 induced concentration-dependent positive and negative
inotropic effects, respectively; both enantiomers reduced spontaneous heart rate but did not influence perfusion pressure.
The maximum increase in force of human atrial trabeculae was 35 % of pre-drug control with [+]-EMD 60263 in comparison to
113 % with forskolin. In guinea-pig papillary muscles, [+]-EMD 60263 and [-]-EMD 60264 had opposite inotropic responses, however,
both agents similarly prolonged action potential duration. Both enantiomers concentration-dependently blocked the rapidly
activating component IKr of the delayed rectifier in guinea-pig myocytes. The block saturated at potentials positive to +30 mV, closely resembling
the effects of the antiarrhythmic agent E-4031 which had been originally used to define IKr. It is concluded, that the positive inotropic action of [+]-EMD 60263 can be explained by prevalence of the Ca2+-sensitizing effect. The accompanying prolongation in action potential duration is caused by block of the IKr component of the delayed rectifier. While the inotropic effects are stereoselective, most of the electrophysiological actions
are clearly independent of sterical configuration. The combination of Ca2+-sensitizing with class-III antiarrhythmic action may provide an interesting pharmacological profile of potential therapeutic
use.
Received: 7 January 1997 / Accepted: 25 February 1997 相似文献
996.
High incidence of nitrosamine-induced tumorigenesis in mice lacking DNA repair methyltransferase 总被引:12,自引:4,他引:8
Iwakuma T; Sakumi K; Nakatsuru Y; Kawate H; Igarashi H; Shiraishi A; Tsuzuki T; Ishikawa T; Sekiguchi M 《Carcinogenesis》1997,18(8):1631-1635
The enzyme O6-methylguanine-DNA methyltransferase repairs alkylation-
induced DNA damage, O6-methylguanine and O4-methylthymine, the former being
formed more frequently. Previously, by means of gene targeting, we
generated mice in which alleles for methyltransferase were disrupted. We
now use these mouse lines, which are totally deficient in methyltransferase
activity, to examine protective effects of the enzyme against tumor
formation. In gene-targeted female mice given an i.p. injection of 5 mg/kg
of dimethylnitrosamine, a larger number of liver and lung tumors occurred,
as compared with normal female mice treated in the same manner. In male
mice given a lower dose of carcinogen, the difference between normal and
gene-targeted mice was statistically insignificant although more tumors did
form in the gene-targeted mice. Methyltransferase apparently afforded
protection from nitrosamine- induced tumorigenesis.
相似文献
997.
Tayama K; Takamori S; Mitsuoka M; Hiraki H; Ohtsuka S; Hayashi A; Aoyama Y; Shirouzu K 《Japanese journal of clinical oncology》1997,27(6):401-405
The aim of this study was to investigate retrospectively the efficacy of
expandable metallic stents (EMSs) for severe respiratory distress in
patients with central airway obstruction. Twenty patients with central
airway obstructions were treated with an EMS. An intraluminal stricture was
present in 15 and an extraluminal stricture in 5 patients. Of the 15
patients with intraluminal stenosis, 11 exhibited symptomatic improvement.
All 11 patients had tumor infiltration occupying less than 50% of the
endoluminal diameter. The other four patients with intraluminal stenosis
had tumor infiltration occupying > 50% of the endoluminal diameter and
demonstrated no improvement. All five patients with extraluminal stenosis
were improved. EMS is useful for an extraluminal stricture in the central
airway and the effect of EMS for intraluminal stenosis is related to the
degree of infiltration and of tumor progression itself.
相似文献
998.
A wound, in the broadest sense, is a disruption of normal anatomic structure and function. Acute wounds progress through a timely and orderly sequence of repair that leads to the restoration of functional integrity. In chronic wounds, this timely and orderly sequence goes awry. As a result, people with chronic wounds often face not only physiological difficulties but emotional ones as well. The study of body image and its damage as a result of a chronic wound fits well with Selder's transition theory. This article describes interviews with seven patients with chronic wounds. The themes that emerged from those interviews were compared with Selder's theory to describe patients' experience with chronic wounds as a transition process that can be identified and better understood by healthcare providers. 相似文献
999.
Changes on serial assessments of brain MRI lesion load are used for monitoring therapeutic efficacy in patients with multiple
sclerosis (MS). We assessed the accuracy and reliability of conventional spin-echo (CSE) and fast spin-echo (FSE) sequences
for measurement of lesion volume using a semiautomated contour technique. Cranial CSE and FSE examinations of 18 patients
with secondary progressive MS were studied. The mean lesion load was slightly higher with the CSE sequence (p = 0.002). Intraobserver
variability was significantly higher for FSE than for CSE, according to both the coefficient of variation between two measurements
(mean 2.48 % and 1.35 % respectively, p < 0.05) and back-transformed 95 % limits of agreement (1.005–1.060 for FSE; 0.988–1.019
for CSE). Although FSE sequences are quicker and the total lesion volume measurements are similar to those obtained with CSE,
the poorer reproducibility raises doubts about the use of FSE to replace CSE in clinical trials.
Received: 26 March 1996 Accepted: 4 April 1996 相似文献
1000.