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1.
Hinrich Böhner Detlef Kindgen-Milles Andreas Grust Rolf Buhl Wolf-Christian Lillotte Barbara T. Müller Eckhard Müller Günter Fürst Wilhelm Sandmann 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2002,387(1):21-26
BACKGROUND: The efficacy of nasal continuous positive airway pressure (nCPAP) as a prophylactic method for preventing cardiopulmonary complications after major vascular surgery has not been investigated. PATIENTS/METHODS: In a prospective randomized trial, 204 patients undergoing elective midline laparotomy for vascular surgery were randomized to receive standard therapy ( n=105) or additional prophylactic nCPAP ( n=99) for the first postoperative night. Postoperative oxygenation, incidence of severe cardiac, and pulmonary complications, length of intensive care surveillance and length of total postoperative hospital stay (LOS) were compared. RESULTS: Prophylactic nCPAP significantly reduced the number of patients with severe oxygenation disturbances defined as paO(2) < 70 mmHg with FiO(2) > or = 0.7 (5 versus 17, P=.01). There were no differences with respect to death, cardiac and pulmonary complications, length of intensive care surveillance or LOS. CONCLUSION: Prophylactic 12 h nCPAP significantly reduces the occurrence of postoperative oxygenation disturbances but has no effect on cardiac or pulmonary complications, need for intensive care, LOS or mortality after major vascular surgery. 相似文献
2.
Driven by widespread concern about transfusion-transmitted disease, intraoperative blood salvage (IBS) and other forms of autologous transfusion are playing an increasing role in medical practice. A quality assurance (QA) program is one of the most important elements of a successful IBS program. A large and successful QA program is described, the key elements of which are: 1) direction by a physician dedicated to the program; 2) use of full-time IBS personnel; 3) use of procedure and training manuals; 4) development of detailed patient identification procedures; 5) quality control of identification procedures, hematocrit, washing efficiency, and sterility; 6) use of extensive patient records; and 7) preventive maintenance procedures. In the past 6 years, 14,522 procedures have been performed and 38,899 salvaged units of blood collected without significant complications. Much of this success is attributed to the comprehensive QA program used during this time. 相似文献
3.
Cat flea, Ctenocephalides felis felis (Bouché), feces are an essential part of larval nutrition under natural conditions. The mass values of adult flea feces can be measured by dissolving samples of flea feces in Drabkin's reagent, filtering, centrifuging, and measuring absorbance spectrophotometrically at 540 nm. Either flea feces or air-dried host blood can be used to generate the standard curve used to convert absorbance (optical density) values into mass values. Debris collected from flea-infested house cats averaged 23.02 mg debris per cat per h with an average of 10.41 mg flea feces per cat per h. Flea feces deposited in the environment serve as potential larval food. Adult flea feces comprised an average of 44.28% of the debris deposited from infested domestic house cats in this study. 相似文献
4.
Hinrich Staecker Stefan Dazert Brigitte Malgrange Philippe P. Lefebvre Allen F. Ryan Thomas R. Van de water 《International journal of developmental neuroscience》1997,15(4-5)
To determine if transforming growth factor alpha (TGFα) pretreatment protects hair cells from aminoglycoside induced injury by modifying their intracellular calcium concentration, we assayed hair cell calcium levels in organ of Corti explants both before and after aminoglycoside (i.e. neomycin, 10−3M) exposure either with or without growth factor pretreatment. After TGFα (500ng/ml) treatment, the intracellular calcium level of hair cells showed a five-fold increase as compared to the levels observed in the hair cells of control cultures. After ototoxin exposure, calcium levels in hair cells of control explants showed an increase relative to their baseline levels, while in the presence of growth factors pretreatment, hair cells showed a relative reduction in calcium levels. Pretreatment of organ of Corti explants afforded significant protection of hair cell stereocilia bundle morphology from ototoxic damage when compared to explants exposed to ototoxin alone. This study correlates a rise in hair cell calcium levels with the otoprotection of hair cells by TGFα in organ of Corti explants. 相似文献
5.
Synthetic and computer-assisted analyses of the pharmacophore for the benzodiazepine receptor inverse agonist site 总被引:2,自引:0,他引:2
M S Allen Y C Tan M L Trudell K Narayanan L R Schindler M J Martin C Schultz T J Hagen K F Koehler P W Codding 《Journal of medicinal chemistry》1990,33(9):2343-2357
The structural requirements for ligand binding to the benzodiazepine receptor (BzR) inverse agonist site were probed through the synthesis and in vitro evaluation of 3-substituted beta-carbolines 6, 7, 11, 12, gamma-carboline 13, and diindoles 18-21, 23-25, 27, 28, and 34. On the basis of the apparent binding affinities of these and other analogues, a hydrogen bond acceptor site (A2) on the receptor is proposed to interact with the N(9) hydrogen atom of the beta-carbolines or the N(7) hydrogen nuclei of the diindoles. Likewise, a proposed hydrogen bond donating site (H1) interacts with the N(2) nitrogen atom of the beta-carbolines or the N(5) nitrogen atom of the diindoles. It appears that interaction with both sites is a prerequisite for high affinity since analogues which have either one or both of these positions blocked exhibit substantial reduction in affinity. Moreover, H1 appears to be capable of engaging in a three-centered hydrogen bond with appropriately functionalized ligands, which explains the increase in potency observed in the following series of 3-substituted beta-carbolines: the n-butyl (12, IC50 = 245 nM), n-propoxy (9, IC50 = 11 nM), and propyl ketone (11, IC50 = 2.8 nM) congeners. In addition to H1 and A2, there appears to be a relatively narrow hydrophobic pocket in the binding cleft that can accommodate substituents at the 3-position of the beta-carbolines which have chain lengths less than or equal to C5. There is a 1 order of magnitude decrease in affinity between n-propoxy analogue 9 (IC50 = 11 nM, chain length = 4) and n-butoxy derivative 7 (IC50 = 98 nM, chain length = 5). Furthermore, alpha- and gamma-branching [e.g. ethoxycarbonyl (2), IC50 = 5 nM and tert-butoxycarbonyl (31) IC50 = 10 nM] but not beta- and delta-branching [e.g. isopropoxy (6), IC50 = 500 nM and (neopentyloxy) carbonyl (48), IC50 = 750 nM] at position 3 are tolerated. Occupation of this hydrophobic pocket is clearly important for high affinity as evidenced by the relatively low affinity of 30, a beta-carboline which possesses a hydrogen atom at the 3-position. This same hydrophobic pocket is partially filled by the D and E rings of the diindoles, which accounts for the high affinity of several members of this series. An excluded volume analysis using selected 3-substituted beta-carbolines and ring-E substituted pyridodiindoles is consistent with the presence of this hydrophobic pocket (see Figure 1).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
6.
Martin Grosse Holtforth Hinrich Bents Birgit Mauler Klaus Grawe 《Clinical psychology & psychotherapy》2006,13(3):172-182
Interpersonal behavior is assumed to be motivated by personal goals that an individual develops ontogenetically to satisfy and protect psychological needs. Interpersonal problems are hypothesized to (1) occur as a consequence of strong avoidance goals and (2) lead to decreased satisfaction of the person's approach goals. The hypotheses are tested using the self‐report data of 284 subjects with predominantly anxiety, affective and eating disorders who applied for treatment in a clinic offering inpatient cognitive–behavioral psychotherapy. Results indicate that interpersonal problems mediate the relationship between avoidance goals and the satisfaction of approach goals. Additional analyses explore specific associations between avoidance goals and certain kinds of interpersonal problem. Avoidance goals are then located within the interpersonal circle structure. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
7.
Kaindl AM Jakubiczka S Lücke T Bartsch O Weis J Stoltenburg-Didinger G Aksu F Oexle K Koehler K Huebner A 《Human mutation》2005,26(3):279-280
Microdeletion syndromes are commonly transmitted as dominant traits and are frequently associated with variably expressed pleiotropic phenotypes. Nonlethal homozygous microdeletions, on the other hand, are very rare. Here, we delineate the fifth and so far largest homozygous microdeletion in nonmalignancies of approximately 400 kb on chromosome 4q11-q12 in a large consanguineous East-Anatolian family with six affected patients. The deleted region contains the beta-sarcoglycan gene (SGCB), the predicted gene SPATA18 (spermatogenesis associated 18 homolog) and several expressed sequence tags. Patients presented with a severe and progressive Duchenne-like muscular dystrophy phenotype, a combination of hyperlaxity and joint contractures, chest pain, palpitations, and dyspnea. 相似文献
8.
9.
Virulent and certain avirulent strains of Bacillus anthracis harbor a plasmid, designated pXO2, which is involved in the synthesis of capsules. Two classes of rough, noncapsulated (Cap-) variants were isolated from the capsule-producing (Cap+) Pasteur vaccine strains ATCC 6602 and ATCC 4229. One class was cured of pXO2, and the other class still carried it. Reversion to Cap+ was demonstrable only in rough variants which had retained pXO2. Proof that pXO2 is involved in capsule synthesis came from experiments in which the plasmid was transferred by CP-51-mediated transduction and by a mating system in which plasmid transfer is mediated by a Bacillus thuringiensis fertility plasmid, pXO12. Cells of Bacillus cereus and a previously noncapsulated (pXO2-) strain of B. anthracis produced capsules after the acquisition of pXO2. 相似文献
10.
Cardiac slowing during elevated intracranial pressure (ICP) could be due to direct activation of central nervous system (CNS) centers or it may be secondary to baroreceptor reflexes activated by the associated pressor response. In five pentobarbital-anesthetized dogs when ICP was raised to 50 mmHg the heart rate decreased 34.4 beats/min (+/-4.8 SE). This cardiac slowing occurred when ICP was elevated after sinoaortic denervation (-24 +/- 4.43 beats/min) and also during elevated ICP when changes in arterial pressure were prevented (-32.3 +/- 4.25 beats/min). These results indicate that the cardiac slowing is largely of CNS origin. In dogs given morphine with pentobarbital to achieve slower heart rates, raising ICP to 50 mmHg by left-sided intracranial balloon inflation led to cardiac dysrhythmias in 9 of 12 dogs. By contrast, raising ICP to 50 mmHg by right-sided intracranial balloon inflation only produced progressive sinus bradycardia. These responses were related to a combined enhancement of vagal and sympathetic activity. Differences observed between right- and left-sides balloon inflation may be partly related to asymmetrical engagement of the cardiac autonomic nerves. The results suggest that left-sided intracranial lesions are more likely to produce cardiac dysrhythmias. 相似文献