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681.
Erdmann D Pippen AM Moquin KJ Sweis R Niklason LE Levin LS Olbrich KC Klitzman B 《Annals of plastic surgery》2004,53(4):398-403
Vascular Endothelial Growth Factor (VEGF), a potent angiogenic, mitogenic and vascular permeability enhancing protein, appears to improve survival of ischemic flaps independent of its route of administration. The purpose of this study was to examine VEGF protein expression in biopsies of surgical flaps with immunohistochemical techniques. In 6 male Yorkshire-type pigs, 10 cm x 15 cm Latissimus dorsi musculocutaneous flaps were elevated bilaterally. Flap zones I, II, and III were established according to their distance from the vascular pedicle. After isolation of the thoracodorsal artery and vein, one flap was randomly assigned to ischemia by temporary occlusion of the vascular pedicle. Ischemia (4 hours) was followed by 2 hours of reperfusion (ischemia group, n = 6). The contralateral (nonischemic) flap served as a control (control group, n =6). Skin and muscle biopsies of flaps were taken at the end of the protocol for immunohistochemical staining using a VEGF antihuman monoclonal antibody.Epidermis of flap skin did not demonstrate VEGF-positive staining, but the dermis and subcutaneous tissue did. Muscle components of biopsies demonstrated staining of interfascicular septa and staining of myocytes. A semi-quantitative scoring system with a scale of 0 to 3 was used for grading of immunohistochemical staining.In skin, areas adjacent to the flap showed an overall mean VEGF staining score of 0.7. All zones of ischemic flaps showed increased mean immunohistochemical staining for VEGF (scores = 1.2, 1.6, and 1.4 in zones I, II, and III, respectively). In muscle, however, only zone I showed increased VEGF immunohistochemical staining from 0.7 in adjacent areas to 1.7 in ischemic flaps. The results indicate only moderate endogenous up-regulation of VEGF in flaps, supporting the utilization of exogenous VEGF as an adjunct in microsurgical therapy. 相似文献
682.
683.
A two-tone oddball procedure was employed to examine the effect of a phonemic category on the mismatch negativity (MMN). One of the stimuli was a phoneme prototype of Japanese /e/, and the other, [e/?], which was perceived by Japanese participants as showing deviance from typicality but is nonetheless included in the category /e/. As control stimuli, a pair of pure tones (1940 and 1794 Hz), corresponding to the F2 frequencies of /e/ and [e/?], respectively, was presented within the same oddball procedure. The MMN for deviant [e/?] revealed greater amplitude than that of deviant /e/, although there was no significant difference in amplitude between the pure tones. The results suggest that a phonemic category determines the auditory sensory memory. 相似文献
684.
A possible diagnostic role of procalcitonin (PCT) as a marker for ventilator associated pneumonia (VAP) in patients with an already triggered acute phase response after successful cardiopulmonary resuscitation (CPR) was investigated. In 28 patients with return of spontaneous circulation (ROSC) after out of hospital CPR, measurements of PCT, C-reactive protein (CrP), white blood cell count (WBC) and body temperature were compared with the clinical course of the patients. In this setting, PCT was the only marker to differentiate between patients with and without VAP (median value on day 1, 6.0 vs. 0.5 ng/ml; P<0.001). Using a cut off value of 1 ng/ml during the first 7 days after ROSC PCT had a sensitivity of 100% and a specificity of 75% to indicate VAP. PCT was elevated a median of 2 days earlier than the clinical diagnosis of VAP. Elevations in PCT can, therefore, indicate bacterial complications in cardiac arrest patients with a non-infectious acute phase response. 相似文献
685.
Emerging viruses: the case 'hantavirus' 总被引:3,自引:0,他引:3
This review briefly summarises the recent knowledge about hantavirus infections and raises particular problems in hantavirus research that need further investigation. The following questions are addressed: (i) are hantaviruses distributed worldwide and what leads to new outbreaks, (ii) what is known about hantavirus evolution, (iii) how can hantavirus species be defined, (iv) what are the determinants of hantavirus pathogenesis in humans, and (v) what problems are associated with the development of new vaccines and antiviral therapeutics. 相似文献
686.
Phase 1 trial of the novel bispecific molecule H22xKi-4 in patients with refractory Hodgkin lymphoma 总被引:2,自引:1,他引:1 下载免费PDF全文
Borchmann P Schnell R Fuss I Manzke O Davis T Lewis LD Behnke D Wickenhauser C Schiller P Diehl V Engert A 《Blood》2002,100(9):3101-3107
CD30 is an excellent target for immunotherapy of Hodgkin lymphoma (HL) because it is overexpressed on Hodgkin and Reed-Sternberg cells. We developed a novel bispecific molecule (BSM) consisting of F(ab') fragments derived from the murine anti-CD30 monoclonal antibody (MoAb) Ki-4 and the humanized CD64-specific MoAb H22. In vitro experiments of H22xKi-4 demonstrated specific phagocytosis of HL-derived cell lines. Patients (pts) with refractory CD30(+) HL were treated with escalating doses of H22xKi-4 at doses of 1, 2.5, 5, 10, and 20 mg/m(2)/d, respectively (administered intravenously on days 1, 3, 5, and 7). The main study objectives were to determine the maximum tolerated dose and the dose-limiting toxicities of H22xKi-4, to define its pharmacokinetic profile, and to document clinical response. Ten pts were enrolled and are evaluable for toxicity and response. Side effects were transient and mild with hypotension (4 of 10), tachycardia (6 of 10), fatigue (10 of 10), and fever (2 of 10 grade I, 3 of 10 grade II). Pharmacokinetic (PK) data revealed an elimination half-life of 11.1 hours, resulting in a significant accumulation of H22xKi-4. The BSM was shown to bind to both monocytes and malignant cells. Response to H22xKi-4 included 1 complete remission (CR), 3 partial remissions (PR), and 4 pts with stable disease. The new BSM H22xKi-4 can be given safely to pts with refractory CD30(+) HL in doses up to 80 mg/m(2) per cycle. Although this dose is not the maximum tolerated dose (MTD) as defined by toxicity criteria, surrogate parameters suggest a biologic effective regimen. H22xKi-4 shows activity in heavily pretreated HL patients warranting further clinical evaluation. 相似文献
687.
Some Trichomonas hominis and Dientamoeba fragilis strains were compared by electrophoretic patterns of total proteins from trophozoites. Easily distinguished patterns divided T. hominis in different types. Significant differences were also seen comparing T. hominis and D. fragilis whilst among strains of D. fragilis electrophoretic protein patterns were mostly found to be accordant. 相似文献
688.
Detlev Ganten Pierre Schelling Paul Vecsei Ursula Ganten 《The American journal of medicine》1976,60(6):760-772
Enzymes, similar to kidney renin, are present in extrarenal tissue of most mammals; they hydrolyze angiotensinogen to form angiotensin I. We suggest that these enzymes be called angiotensinogenases. Angiotensinogenase concentrations in extrarenal tissue can exceed those in the kidney. The enzyme has been obtained in pure crystalline form. Angiotensinogenases are part of a complex enzyme system which leads to local production of angiotensin. Results indicating a biologic role of the angiotensinogenase system in brain, adrenal gland, uterus and tissue culture are discussed. 相似文献
689.
690.
Detlev H. Krüger Susanna Prsch Monika Reuter Werner Goebel 《Journal of basic microbiology》1990,30(9):679-683
The recognition sequence 5'-CC(A/T)GG for EcoRII in the bacteriophage T7 genome is refractory to this restriction endonuclease, despite not bearing the specific (protective) methylation. Following the integration of this site as part of a 219 bp fragment (in which the recognition sequence is flanked by about 100 bp of T7 origin) into the EcoRII-sensitive vector pUC18, the T7 site becomes susceptible to cleavage, too. The same is true of recombinant pBR322 plasmids containing the T7-derived recognition site. The results show that the flanking sequences are not immediately responsible for the refractory behaviour of EcoRII sites and are in agreement with data according to which EcoRII requires the coordinated presence of at least two recognition sites in its DNA substrate. 相似文献