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41.
Phrenic and cervical sympathetic nerve responses to hypercapnia were examined before and after anesthesia in twelve midcollicularly decerebrated, vagotomized, glomectomized, paralyzed and ventilated cats. We measured responses of integrated phrenic and cervical sympathetic nerve activities to increases in end-tidal PCO2 (PETCO2) from apneic threshold to approximately 30 torr above threshold. All cats were studied first in the unanesthetized state. Six cats were then restudied after a quarter of a usual dose of chloralose/urethane (10 mg/kg and 62.5 mg/kg, respectively) and then after half the usual dose of chloralose/urethane (20 mg/kg and 125 mg/kg). The other six animals were restudied after quarter of a standard dose of pentobarbital (9 mg/kg), after half the standard dose (18 mg/kg) and then after the full (35 mg/kg) dose. Both anesthetic agents led to significant increases in apneic thresholds for both phrenic and sympathetic nerve activities. These agents also caused dose-dependent decreases in peak, tonic and respiratory-related sympathetic nerve activities. Peak (tidal) phrenic nerve activities, in comparison, were much less affected by the anesthetic agents. CO2 response curves showed that both of these anesthetic agents depressed, at any given level of PETCO2, respiratory-related sympathetic nerve responses more than the responses found in the phrenic nerve. We conclude that the relations between peak, tonic (i.e. between phasic bursts) and respiratory-related sympathetic nerve activities and phrenic nerve activity can be altered by anesthesia. 相似文献
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S M Hanash J R Strahler J V Neel N Hailat R Melhem D Keim X X Zhu D Wagner D A Gage J T Watson 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(13):5709-5713
Two-dimensional (2D) PAGE, using carrier ampholytes for the first-dimension separation, has provided a tool for the simultaneous analysis of cellular proteins. To extend the utility of 2D PAGE to the preparative level, we have investigated the use of immobilized pH gradients (IPG) for the first-dimension separation. The results we have obtained indicate that as much as 1 mg of cellular protein can be loaded onto a single IPG gel without loss of resolution. Mutant polypeptides previously detected in carrier ampholyte-based 2D gels were equally detectable in IPG-based 2D gels. With IPG gels several hundred cellular polypeptides can be isolated, from as few as 10 gels, in sufficient amount for sequencing with current sequencing technology. We therefore conclude that IPG greatly enhances the prospects for the large-scale sequencing of cellular proteins for the development of 2D gel-related protein data bases and for the identification of new polypeptide gene products, with the attendant implications for a genome sequencing effort. 相似文献
45.
Evaluation of intrinsic and extrinsic motivation interventions with a self-help smoking cessation program 总被引:8,自引:0,他引:8
Personalized feedback and a financial incentive, developed from an intrinsic/extrinsic motivation framework, were evaluated as adjuncts to self-help materials for smoking cessation. Ss (N = 1,217) were randomized to 4 treatment groups and were followed up at 3 and 12 months. Consistent with hypotheses derived from the motivation framework, the financial incentive increased the use of self-help materials, did not increase cessation rates among program users, and was associated with higher relapse rates among those who did manage to quit. The personalized feedback increased both smoking cessation and use of the materials 3 months after distribution of the materials. Continuous abstinence (abstinence at 3 and 12 months) in the group that received the personalized feedback alone was twice the rate of the other groups. 相似文献
46.
With increasing numbers of primary anterior cruciate ligament reconstruction, the incidence of unsatisfactory results and graft failures will increase. The goals of revision reconstruction are similar to those of primary reconstruction and include stabilization of the knee, prevention of secondary degenerative changes, and recovery of knee function. Besides the recurrent tear there are specific technical failures, such as tunnel malplacement and unrecognized associated ligamentous pathologies, which might lead to graft failure. Thus, preoperative planning includes a detailed analysis of failure mechanisms by thorough preoperative history taking, comprehensive physical examination, and appropriate radiographic evaluation. The treatment algorithm addresses issues of hardware removal, need for a staged procedure or concomitant surgery, graft source, tunnel placement, and graft fixation. Correct placement of tunnels and graft fixation are the essential surgical steps, which might also influence graft selection. Successful revision ACL surgery requires a motivated and compliant patient and an experienced surgeon who is proficient in a variety of different surgical techniques. However, since clinical outcome is reported to be inferior in revision compared to primary ACL reconstruction the importance of counseling the patient preoperatively regarding less satisfactory results than in most primary ACL reconstructions must be emphasized. This article describes indications, analysis and surgical procedures for revision anterior cruciate ligament reconstruction. 相似文献
47.
A kinetic study of leucine metabolism in severely burned patients. Comparison between a conventional and branched-chain amino acid-enriched nutritional therapy. 下载免费PDF全文
A cross-over design study was used to examine the metabolic consequences of enteral feeding for 48 to 96 hours with either a branched-chain amino acid (BCAA)-enriched (44% BCAA) or a conventional egg protein formulation in 12 severely burned adult patients. A stable isotope labeled leucine (L-1-13C-leucine) tracer approach was used to measure leucine flux and oxidation and to estimate rates of whole body protein synthesis and breakdown. Additionally, 15N2-urea and 6,6-2H-glucose were administered to assess the status of urea and glucose kinetics with these two nutritional treatments. Average patient age was 54 years, and average burn surface area was 36%. Studies were conducted at an average of 25 days postburn. Leucine flux and oxidation were significantly (p less than 0.01, by paired t-test) elevated with BCAA feeding as compared to the egg protein formulation. However, there were no significant differences in the rates of leucine incorporation into, or release from, proteins (p greater than 0.05) between the two dietary periods. Mean rates of body protein synthesis and breakdown for each diet were about twice the rates reported for healthy young adults. Apparent nitrogen balance measurements were not statistically different (p greater than 0.1) between the two diet periods. Furthermore, urea and glucose kinetics failed to show significant differences between the two diet periods. It appears from these results that the major consequences of increased intake of leucine from the BCAA formula is an enhanced rate of leucine oxidation. In conclusion, (1) the availability of BCAAs is not rate-limiting for enhanced protein synthesis in burn patients, and (2) the use of enriched BCAA formulas in burn therapy does not appear to offer advantages over a routinely used enteral egg protein formula, at least based on the present determinations. 相似文献
48.
Volkmar Heppert Christof Wagner Ulrich Glatzel Andreas Wentzensen 《Trauma und Berufskrankheit》2002,4(1):114-120
Osteomyelitis patients feel their social and professional existence is threatened. Health insurances are faced with total treatment costs for each patient with osteomyelitis, which can reach 500.000,00 EUR. We must therefore make every effort, from the first onset of infection, to prevent the condition from becoming chronic and thus keep the potential problems to patients and insurance companies to a minimum: once the condition has become chronic there is absolutely no guarantee that treatment will be successful. Treatment must start with the removal of absolutely all necrotic tissue – soft tissue and bone – and of all implants. As in tumor surgery, en bloc resection is best. Up to now there is still no means of determining the exact limits of the infection. The surgeons's personal experience with osteomyelitis is the most important factor both in the treatment of these cases and therefore in the containment of treatment costs. Bone reconstruction is attempted after the soft tissue defects have been treated, either by bone grafting (defect < 3 cm) or by segment transfer. Modern techniques of reconstruction surgery can yield quite good results even in chronic oxteomyelitis, providing management has been optimum throughout. Patients with osteomyelitis should therefore be treated in specialist hospitals. 相似文献
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István Pintér János Mátyus Zoltán Czégány Judit Harsányi Marietta Homoki Miklós Kassai Eva Kiss István Kiss Erzsébet Ladányi Lajos Locsey Lajos Major Mihály Misz Lajos Nagy Kálmán Polner Jeno Rédl István Solt Béla Tichy Marietta T?r?k Gábor Varga Gyula Wagner Imre Wórum Béla Zsoldos László Pótó Katalin Dérczy István Wittmann Judit Nagy 《Nephrology, dialysis, transplantation》2004,19(4):840-843
BACKGROUND: The diagnosis of analgesic nephropathy has improved significantly with modern imaging techniques. We reviewed a large portion of the Hungarian dialysis population to obtain additional insight into the problem. METHODS: Twenty-two participating dialysis units enrolled 1400 patients on renal replacement therapy between 1 January 1995 and 1 January 1998. Patients with no known aetiology (n = 284) were interviewed and studied with renal imaging. We assessed the presence of decreased renal mass combined with either bumpy contours, papillary calcification, or both. The subjects studied were interrogated extensively. RESULTS: Our survey suggested analgesic nephropathy in 47 of 1400 patients (3.3%), 3-fold higher than the EDTA database estimate for Hungary. The analgesics most commonly abused were phenacetin-containing mixtures. The driving symptoms were mainly headache and joint pain. Cardiovascular complications were more common than in the rest of the dialysis population, independent of smoking and lipid values (P<0.01). CONCLUSIONS: Phenacetin should be banned. Our study results support the need for longitudinal cohort and case-control studies in Hungary. 相似文献