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1.
2.
Dr. S. Besier T.M. Bingold F. Walcher K. Engels B. Spellerberg V. Brade C. Brandt 《Der Chirurg》2007,78(12):1148-1151
Streptococcus agalactiae, known as a pathogen that causes meningitis and septicemia in neonates, emerges as an invasive organism in nonpregnant adults. This case report describes the fulminant course of a necrotizing fasciitis (NF) with streptococcal toxic shock-like syndrome (STSS) in a 76-year-old diabetic patient caused by S. agalactiae, serotype V. Chronic diseases and immunodeficiency are considered to be risk factors for the acquisition of group B streptococcal disease. Since early surgical treatment in conjunction with antimicrobial and intensive care therapy is critical for the outcome of patients with NF and/or STSS, clinicians should be aware of invasive S. agalactiae infections in adults with subcutaneous emphysema. 相似文献
3.
Selma C. Tromp Geert Jan Tangelder Dick W. Slaaf Robert S. Reneman S. van Velzen Wim Engels E. van Breda M. G. A. oude Egbrink 《Pflügers Archiv : European journal of physiology》1998,436(2):255-261
The objective of the present study was to determine the role of mast cells and histamine in leukocyte-endothelium interactions
in mesenteric venules of four rat strains: Brown Norway, Lewis, Sprague-Dawley and Wistar. Intravital microscopy showed that
the mast cell stabilizer cromoglycate (5 mg/kg i.v. just before exteriorization of the mesentery) did not affect the baseline
level and velocity of leukocyte rolling in any of the four strains. This finding is in agreement with the observation that
cromoglycate pretreatment only slightly influenced mast cell degranulation in all strains except the Brown Norway. After mast
cell stabilization, only in Sprague-Dawley did topical administration of histamine (10–4 M) result in a significant increase in the level of leukocyte rolling and a decrease in the rolling velocity compared with
the time control. Histamine induced leukocyte adhesion only in the Brown Norway strain. In conclusion, the hypothesis presented
in other studies, that degranulation of mast cells, and more specifically the release of histamine, is of major importance
for the induction of leukocyte-endothelium interactions in rat mesenteric venules is not generally applicable; the present
study shows a clear strain dependency.
Received: 18 July 1997 / Received after revision: 17 November 1997 / Accepted: 13 March 1998 相似文献
4.
Frank de Vocht Berna van-Wendel-de-Joode Hans Engels Hans Kromhout 《Magnetic resonance in medicine》2003,50(4):670-674
The interactive use of magnetic resonance imaging (MRI) techniques is increasing in operating theaters. A study was performed on 17 male company volunteers to assess the neurobehavioral effects of exposure to magnetic fields from a 1.5 Tesla MRI system. The subjects' neurobehavioral performances on a neurobehavioral test battery were compared in four 1-hr sessions with and without exposure to magnetic fields, and with and without additional movements. Adverse effects were found for hand coordination (-4%, P < 0.05; Pursuit Aiming II) and near visual contrast sensitivity (-16% and -15%, P < 0.10; Vistech 6000). The results from the remaining tests were inconclusive due to a strong learning effect. No additional effect from gradient fields was detected. The results indicate that working near a 1.5 Tesla MRI system may lead to neurobehavioral effects. Further research is recommended, especially in members of operating teams using interactive MRI systems. 相似文献
5.
C. L. G. Ham J. M. L. Engels G. T. van de Wiel A. Machielsen 《Journal of magnetic resonance imaging : JMRI》1997,7(5):933-937
The application of high gradient amplitudes and switching rates for MRI and spectroscopy, resulting in short rise times for the gradient field and high changes of the magnetic flux density in the patient, is known to possibly evoke peripheral nerve stimulation (PNS) in patients. These effects have been studied on 20 volunteers under different experimental circumstances. The results of these measurements are partially in line with earlier findings reported in the literature. New information is found for the dependence of the PNS threshold level as a function of the rise time of the gradient waveform. The PNS threshold level, expressed in terms of dB/dt, is found to be proportional with t?05, where t is the switch time for the gradients. Indications are found that |B|, the modulus of the gradient vector field, is more closely related to the PNS threshold level than Bz, the imaging component of the gradient field. From the experiments, it is furthermore concluded that only for the imaging protocols characterized by the application of long bipolar repetitive gradient pulse trains, such as echo-planar imaging, PNS is expected at the reported threshold levels. For the protocols based on spin echo, turbo spin echo, inversion recovery, fast field echo, etc., characterized by shorter gradient pulse trains, the threshold levels are expected to be much higher. 相似文献
6.
D. Engels T. Madaras S. Nyandwi J. Murray 《Bulletin of the World Health Organization》1995,73(6):787-791
Annual epidemics of bacillary dysentery have been a public health problem in Burundi for the last 14 years. Recent civil unrest, resulting in the displacement of large numbers of people into refugee settlements, has aggravated the situation. We report the results of a nationwide, health-centre based, sentinel site survey to check the drug resistance of Shigella dysenteriae type 1 (Sd1), the causal organism of such epidemics. Shigella spp. (of which 97% were Sd1) were isolated from 73% of the 126 specimens collected from six main sites around the country. There was no difference in culture results from fresh and frozen stool specimens. Overall Sd1 resistance to commonly available antibiotics (sulfamethoxazole + trimethoprim, ampicillin, tetracycline, and chloramphenicol) varied from 77% to 99% and was fairly uniformly distributed over the country. All Sd1 isolates were susceptible to newer drugs, such as ciprofloxacin and ceftriaxone. Resistance to nalidixic acid, the current first line of treatment for bacillary dysentery in Burundi, varied from 8% to 83% in the different sentinel sites; global resistance was 57%. 相似文献
7.
8.
A One–Step, Operator–Independent Method for Isolating Islets of Langerhans from the Porcine Pancreas
Christophe Arbet–Engels Sylviane Darquy Frédérique Capron Maria E. Pueyo Sophie Dimaria Vincent Poitout Gérard Reach 《Artificial organs》1994,18(8):570-575
Abstract: Large–scale isolation of islets of Langerhans is one of the major obstacles in islet transplantation. Until now, isolation methods relied on enzymatic digestion, the duration of which relies on a decision dictated by the operator's experience. This approach has always hindered development of an automated method. The aim of this study was to develop a one–step method based on complete digestion of the pancreas. The original aspect of the technique (derived from the Ricordi method) is use of the University of Wisconsin (UW) solution in the digestion medium and a continuous flow collagenase processing circuit with local cooling and rewarming to allow tissue digestion to proceed at 37°C while settling of the cell suspension takes place at 4°C. A stopcock system permits the alternate use of two settling chambers so that while one is in the circuit, the other can be removed for cen–trifugation, resuspension of the crude islet preparation in collagenase in free UW solution, and further purification in a density gradient system. Ten experiments were performed, and 545, 750 ± 48, 670 purified pig islets were obtained per totally digested pancreas. Histological studies showed cell integrity. Insulin secretion in response to double glucose stimulation under perfusion conditions demonstrated the functional viability of the isolated islets. In conclusion, this one–step method makes it possible to obtain a high number of viable islets of Langerhans in the absence of any decision by an operator, and it should therefore provide basis for an automated method. 相似文献
9.
Analysis of a familial three way translocation involving chromosomes 3q, 6q, and 15q by high resolution banding and fluorescent in situ hybridisation (FISH) shows two different unbalanced karyotypes in sibs. 总被引:1,自引:0,他引:1
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D Wieczorek H Engels R Viersbach B Henke G Schwanitz E Passarge 《Journal of medical genetics》1998,35(7):545-553
We report on a familial three way translocation involving chromosomes 3, 6, and 15 identified by prometaphase banding and fluorescence in situ hybridisation (FISH). Two mentally retarded sibs with different phenotypic abnormalities, their phenotypically normal sister and mother, and two fetuses of the phenotypically normal sister were analysed. The terminal regions of chromosomes 3q, 6q, and 15q were involved in a reciprocal translocation, in addition to a paracentric inversion of the derivative chromosome 15. Conventional cytogenetic studies with high resolution GTG banding did not resolve this rearrangement. FISH using whole chromosome paints (WCPs) identified the chromosomal regions involved, except the aberrant region of 3q, which was undetectable with these probes. Investigation of this region with the subtelomeric FISH probe D3S1445/D3S1446 showed a balanced karyotype, 46,XX,t(3;15;6) (q29;q26.1;q26), inv der(15) (q15.1q26.1) in two adult females and one fetus. It was unbalanced in two sibs, showing two different types of unbalanced translocation resulting in partial trisomy 3q in combination with partial monosomy 6q in one patient and partial trisomy 15q with partial monosomy 6q in the other patient and one fetus. These represent apparently new chromosomal phenotypes. 相似文献
10.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献