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31.
BACKGROUND The reconstruction of large defects of the scalp after wide excisional surgery of cutaneous malignancies is challenging. When the pericranium must be resected due to safety considerations, the exposed bone complicates reconstructive approaches.
OBJECTIVE The objective was to develop an improved technique for reconstructive surgery of full-thickness scalp defects.
METHODS Full-thickness scalp defects of up to 126 cm2 in size with exposure of denuded bone were treated by partial removal of the outer table of the skull. The diploic space exposed by this treatment showed petechial bleeding and was covered with a dermal regeneration template (Integra, Integra Lifesciences Corp., Plainsboro, NJ). After transformation of the template by vascularization and by proliferation of fibroblasts, an ultrathin skin graft was transplanted onto the neodermis.
RESULTS Thirteen patients with cutaneous malignancies of the scalp were treated using this technique. The defects were transplanted within a median postoperative time period of 29 days (± 4 days) and showed good cosmetic results and stable scars. After a follow-up period of 6 months, no local recurrences were observed.
CONCLUSION This reconstructive procedure allows closure and rapid healing of large scalp defects in which the pericranium had to be resected.  相似文献   
32.
We describe our approach of posterior ligation of the renal artery during resection of large hypervascular right renal tumors. This technique uses en bloc mobilization of the inferior vena cava and renal tumor to ligate the renal artery at its origin from the aorta. In our experience, the use of this posterior approach for renal artery ligation is safe and effective, even with large renal tumors with multiple collaterals and/or lymph nodes making the identification of the renal artery difficult.  相似文献   
33.
Triosephosphate isomerase deficiencies in erythrocytes and leucocytes were discovered in three unrelated families by a heterozygote screening of 3000 blood samples. In addition, a family found by Schroter et al. [not published] was studied. In these four families, only heterozygote carriers were found. In the family described by Freycon et al. with hetero- and homozygote carriers of triosephosphate isomerase deficiency, the heterozygotes were reinvestigated. There was 51% of normal enzyme activity in three of the families. In the other two families the enzyme activity was 64% and 71% of normal. Two of the eleven heterozygotes, both children, were diseased, but it seems unlikely that the disorders resulted from the deficiencies. The activities of thirteen enzymes, the Km of triosephosphate isomerase for glyceraldehyde phosphate and the concentrations of metabolites were normal. Antibody titration showed normal specific activities in four families and 50% of normal in one family. No electrophoretic variant was detected. From the proved heredity, a heterozygous frequency of at least 1/1000 is indicated. A maximal frequency of 5/1000 is estimated by using further instances of triosephosphate isomerase deficiency where heredity has not yet been investigated. An explanation for the small number of known cases is that this enzyme is not routinely assayed.  相似文献   
34.
The intraindividual changes of ventricular late potentials and their possible determinants were examined prospectively in 88 consecutive patients (male: 75; mean age: 58 ± 9 years) after thrombolytic therapy for acute myocardial infarction. Late potential analysis was performed 4 weeks and 12 months after acute myocardial infarction. At the same time, a left heart catheterization was performed to assess the extent of coronary heart disease and left ventricular ejection fraction. The incidence of late potential 4 weeks after acute myocardial infarction was 15% (13/88 patients). Eighteen percent (16/88) of the patients revealed changing results of late potential analysis: 9 patients lost late potential (late potential pos./neg.) 1 year after acute myocardial infarction and 7 patients presented new formation of late potential (late potential neg./pos.). Preserved late potentials were found in four patients (late potential pos./pos.). Late potential analysis remained negative in 68 patients (late potential neg./neg.). There was no influence of age, gender, site of infarction, clinical course, and medical treatment on the natural course of late potential. Changing results of late potential analysis seemed to be correlated with the evolution of left ventricular ejection fraction and the dynamics of coronary heart disease. In the group late potential pos./pos., comparable values for left ventricular ejection fraction were measured at both examinations, whereas late potential neg./neg. had a significant increase in ejection fraction. In the group late potential pos./neg., a significant improvement in left ventricular function was also measured. In contrast, the late potential neg./pos. group tended to have lower left ventricular ejection fractions 1 year after infarction. In the late potential neg./pos. and late potential pos./pos. groups, the extent of coronary artery disease returned to conditions comparable to baseline despite an initial reduction after coronary revascularization performed 4 weeks after infarction. Late potential neg./neg. and late potential pos./neg. revealed a stable benefit gained from coronary revascularization with a persistent reduction in the number of diseased vessels. Dynamic changes in the results of the signal-averaged ECG 1 year after thrombolytic therapy for acute myocardial infarction were observed in 18% of the patients. These changes seem to be correlated with the evolution of left ventricular function and the dynamics of coronary artery disease.  相似文献   
35.
The impact of different vaccine administrations in the Federal Republic of Germany, in relation to vaccine-associated paralytic poliomyelitis (VAPP) was studied. (This only means that on the basis of the temporal relation of vaccination and onset, the vaccine cannot be ruled out as possible cause.) Oral polio vaccine (OPV) was given between 1963 and 1977 only and recommended simultaneously with inactivated vaccines (DT/DPT) between 1980 and 1985. In the first period 10 VAPP cases occurred among 9.96 million estimated vaccinees aged under 2 years. In the second period 6 cases of provocation poliomyelitis (PRP) were found among 2.9 million estimated OPV/DT/DPT vaccinees of the same age group. Statistically the VAPP/PRP frequencies in the two periods studied did not achieve significance.  相似文献   
36.
Background: Tissue proliferation is the major cause of in-stent restenosis (ISR). Thus, debulking of material should be the most favorable method to treat ISR. The present study was performed to test the clinical and angiographic outcome of directional coronary atherectomy (DCA) in the treatment of restenosis within different stents. Methods and Results: Fifty patients with ISR in single stents (12 Palrnaz-Schatz stents, 8 Pura stents, 10 Multilink stents, 10 NIR stents, 8 Wallstents, and 2 Microstents) underwent DCA with adjunctive balloon angioplasty in 38 patients. Primary success was achieved in 48 patients (96%). Two patients developed CK-MB elevations, one with a Q-wave infarction. Some minor technical problems occurred with respect to the different stent types. The percent diameter stenosis decreased from 76 ± 7% at baseline to 29 ± 6% after atherectomy (P < 0.0001) and 20 ± 4% after adjunctive PTCA, and it increased to 45 ± 19% at 4-month angiography (P < 0.0001). Angiographic restenosis occurred in 14 (29.2%) of 48 patients who were reevaluated after 4 months. Conclusion: While DCA is able to remove u significant amount of intimal tissue in selected patients with in-stent restenosis, new atherectomy catheter designs are required to make this a feasible and safe procedure.  相似文献   
37.
We hypothesized that pacing at sites other them the right ventricular (RV) apex or at two or more ventricular sites would activate the myocardium more rapidly and improve cardiac function in patients undergoing coronary revascularization or aortic valve replacement. Epicardial electrodes were placed on the right atrium (A), RV paraseptal area close to the RV apex (B), RV outflow tract (C), LV apex (D), in patients undergoing bypass surgery. At constant rate and AV delay, we measured CO during A pacing, DV1 pacing at B, C, D, and various combinations of sites in random order in ten patients with EF > 50% and 27patients with EF ≤ 50%. When pacing at two sites, we made one electrode a cathode and one an anode and noted two distinct thresholds by careful observation of the 12-lead ECG. There were no significant differences in CO, systemic vascular resistance, systolic, or mean arterial pressure. Significant differences were noted in QRS duration, which increased progressively going from AAI to 3-site, 2-site, and single site pacing (P < 0.05 each comparison). Thus: (1) QRS duration correlated inversely with the number of ventricular sites paced; (2) despite this, CO did not improve irrespective of baseline EF; (3) multisite pacing produced multiple distinct thresholds which appeared to be related to the number of sites paced, and (4) unique ECG patterns confirmed multisite pacing.  相似文献   
38.
Neonatal rat cartilage has the capacity for tissue regeneration   总被引:2,自引:0,他引:2  
One of the most relevant issues in future medicine is tissue regeneration. Transplantation medicine alone cannot solve the problem of incurable conditions of vital organs. One approach to this might be the replication of the spontaneous regeneration that is found in embryonic/neonatal tissue. In this study, a tissue model for basic investigation of regeneration mechanisms in vivo was established. We demonstrated by histology and immunohistochemical staining for types I and II collagen that neonatal rat cartilage unlike adult cartilage has the capacity for rapid scarfree regeneration after full-thickness incision. The underlying mechanism was identified in the preserved proliferative capacity of neonatal chondrocytes. This in vivo model should prove useful in further studies of the role of cellular (e.g., GA cell cycle regulators) and extracellular (e.g., cytokines) factors in tissue regeneration and wound healing.  相似文献   
39.
The present study investigated the effect of 48 h of water deprivation on eating behavior of 12 lactating cows fed grass and corn pellets ad lib. Water deprivation reduced grass and corn pellet intake significantly, with corn pellet intake decreasing earlier than grass intake. The reduction of feed intake was entirely due to a reduction of meal size for both grass and corn-pellet meals. The size of the first meal of the water deprivation period was already reduced by about 30%. Grass-meal frequency increased, whereas corn-pellet meal frequency decreased during water deprivation. Water deprivation also decreased live weight and milk yield by about 12 and 30%, respectively. All parameters returned to baseline values with rehydration. With ad lib access to feed and water, 77% of drafts occurred in relation to meals, but the number of meals clearly exceeded the number of drafts. The results demonstrate that water deprivation rapidly leads to premature meal termination. This is in line with the assumption that an enhanced prandial increase in ruminal fluid osmolality contributes to dehydration-induced hypophagia. Yet, further studies are necessary to prove this assumption and to better understand the complex relationships between eating and drinking in ruminants.  相似文献   
40.
In 1985 a high HIV-seroprevalence (44.2%) was found in a cohort of parenteral drug addicted prisoners in Innsbruck, Austria. In a longitudinal study from March 1985 to March 1989 we investigated the epidemiology of HIV-infection as well as possible changes in the drug taking behaviour of this defined population at risk. During the study HIV-seroprevalence rates in drug dependent prisoners showed a statistical decrease to 30%. A concomitant increase in admission to any kind of therapy programmes as well as an increasing change from ‘heavy use’ (mainly taking heroin i.v.) to ‘non-heavy use’ (mainly taking drugs orally) could be noted. The influence of preventive measures, such as comprehensive AIDS-information, special therapy programmes including the methadone substitution programme, and the unrestricted availability of needles and syringes is discussed.  相似文献   
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