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31.
Stone ME  Soong W  Krol M  Reich DL 《Anesthesia and analgesia》2002,95(1):42-9, table of contents
IMPLICATIONS: The number of patients supported by ventricular assist devices (VADs) that present for noncardiac surgery is increasing in our institution. Our recent experience with eight such patients is reported, along with a review of the most commonly implanted VADs and the anesthetic implications and considerations for VAD-supported patients undergoing noncardiac surgery.  相似文献   
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Ruszat R  Wyler S  Forster T  Reich O  Stief CG  Gasser TC  Sulser T  Bachmann A 《European urology》2007,51(4):1031-8; discussion 1038-41
OBJECTIVES: Ongoing oral anticoagulation (OA) contraindicates transurethral electroresection of the prostate. We evaluated the safety and effectiveness of photoselective vaporization of the prostate (PVP) in patients on ongoing OA with coumarin derivatives, aspirin, or clopidogrel, complaining of symptomatic benign prostatic hyperplasia (BPH). METHODS: We evaluated perioperative parameters, functional outcome, and adverse events up to 24 mo postoperatively of patients on OA, and compared results with 92 men at normal risk without anticoagulant therapy undergoing PVP for the same indication (control). RESULTS: Within 40 mo, 116 men on OA were included, with 31% (n=36) receiving coumarin derivatives; 61% (n=71), aspirin; and 8% (n=9), clopidogrel. Mean prostate volume (62+/-34ml vs. 57+/-25ml; p=0.289) and mean operation time (67+/-28min vs 63+/-29min; p=0.313) were comparable with control. We observed no bleeding complications necessitating blood transfusions. Average postoperative decrease of haemoglobin was 8.6% for patients on OA versus 8.8% for control. At 3, 6, 12, and 24 mo postoperatively, improvement of the International Prostate Symptom Score ranged from 60-70%; postvoid residual volume, 80-88%; and average maximum urinary flow rate, 116-140%, respectively. Postoperative complications were low and comparable with control. CONCLUSIONS: PVP is characterized by excellent haemostatic properties and very low intraoperative complication rate even in patients on OA. On the basis of our perioperative results, we recommend PVP as first-line procedure for patients with symptomatic BPH at high risk of bleeding.  相似文献   
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OBJECTIVE: Conventional transurethral resection of the prostate (TURP) uses a monopolar electrocautery system in which the current passes from the active electrode through the patient's body towards the return plate and may cause distant negative effects. In this study a new developed resection device, the Vista system, using a bipolar electrocautery system and 0.9% sodium chloride solution for irrigation, was evaluated in an ex-vivo model. METHODS: The modified model of the isolated blood perfused kidney was used to determine cutting qualities, ablation rate, blood loss and coagulation depth of the bipolar resectoscope. After ablating the renal tissue of a perfused kidney in a surface area, blood loss was semiquantitatively determined. Afterwards samples were taken and processed for histological evaluation of the coagulation depth. We compared the new bipolar resection device against a conventional monopolar resectoscope. RESULTS: We found good cutting qualities of the bipolar resectoscope although it is more difficult to start a cut. The ablation rate is determined by the width of the electrode and is similar to the standard device (30 cm(2)/min). The bleeding is reduced with increasing output powers (26.13 +/- 6.15 g/min (level 5); 20.49 +/- 5,47 g/min (level 6); 13.16 +/- 5,47 g/min (level 7); 10.43 +/- 4.76 g/min (level 8) and lower compared to a conventional monopolar resectoscope (17.08 +/- 4.47 g/min). The coagulation depth increases with higher output powers but is reduced compared to the standard device (118 +/- 22 microm (level 5); 121 +/- 23 microm (level 6); 141 +/- 62 microm (level 7); 163 +/- 30 microm (level 8) versus 287 +/- 57 (monopolar resectoscope)). CONCLUSION: Our results with the bipolar resection device for TURP suggest that it may offer an alternative to conventional TURP. As active and the return electrode are placed on the resectoscope, high current densities are achieved locally and complications caused by distant negative effects of the current are theoretically reduced in vivo. Furthermore the risk of TUR syndrome is theoretically eliminated by using physiological sodium chloride solution for irrigation. To prove the clinical significance of our ex-vivo findings, clinical studies including large numbers of patients have to be performed.  相似文献   
36.
The involvement of collagenolysis in ovulation in the rat   总被引:6,自引:0,他引:6  
Collagenolytic activity in ovarian follicles was previously demonstrated by using synthetic peptides and reconstituted collagen fibers. However, attempts to demonstrate degradation of ovarian collagen and to correlate collagenase activity with ovulation were not successful. By administration of L-(5-3H) proline, we have labeled ovarian and follicular collagen and followed collagenolytic activity by separation of 3H-hydroxyproline (3H-Hyp) from acid hydrolyzates of ovarian tissue by HPLC. The level of ovarian and follicular 3H-Hyp decreased by about 40% on the afternoon of proestrus or after exogenous stimulation of ovulation by human CG (hCG), and this decrease was abolished by blocking the surge of gonadotropins with Nembutal. To verify that the observed reduction in 3H-Hyp was due to the action of a typical collagenase, the collagenous fraction was prepared from ovarian tissue and from preovulatory follicles before and after the ovulatory stimulus. The extracts were treated with trypsin (25 min, 25 C, 0.01 mg/ml) plasmin and p-amino-phenyl-mercuric acetate to fully activate the collagenase extracted along with collagen. Both, enzymatic and chemical activation of collagenase in vitro resulted in degradation of collagen. This degradation could be inhibited by cysteine and EDTA; both are classic inhibitors of mammalian collagenases. The activity of ovarian collagenase increased within 3 h after hCG-stimulation, peaked at 5-fold 6 h after hCG, and declined afterwards. Administration of cysteine (0.001-0.01 mmol) into the bursal cavity of proestrous rats blocked ovulation and breakdown of ovarian collagen in a dose-dependent manner. Cysteine effectively inhibited ovulation even when injected 7 h after the hCG stimulus. Inhibitors of arachidonic acid metabolism prevent ovulation. Indomethacin (inhibitor of cyclooxygenase) and nordihydroguaiaretic acid (inhibitor of lipoxygenase) blocked ovulation and inhibited hCG-induced ovarian collagenolysis. Collectively, these results corroborate the essential role of collagenolysis in follicular rupture in mammals.  相似文献   
37.
OBJECTIVE: To compare the haemostatic properties of standard transurethral resection of the prostate (TURP) and transurethral vaporization resection of the prostate (TUVRP), as perioperative bleeding is still regarded as the major complication of prostate resection. MATERIALS AND METHODS: Isolated blood-perfused porcine kidneys were used to determine the haemostatic efficacy of TURP and TUVRP (using two different electrodes). Bleeding was quantified precisely in relation to tissue ablation for the two techniques, and specimens were evaluated histologically. RESULTS: Both TUVRP groups had significantly less bleeding (P = 0.005) than the TURP group for a standardized ablation volume of perfused kidney tissue (18.9, 19.5 and 24.1 mL/min, respectively). The different TUVRP electrodes had no significant haemostatic differences. The histology showed significantly (P = 0.03) larger coagulation zones for the TUVRP groups than for standard TURP. CONCLUSIONS: TUVRP ex-vivo was associated with significantly better haemostasis than TURP. The haemostatic properties of different active electrodes for TUVRP seem to be equivalent.  相似文献   
38.
The special interest group on sensitive skin of the International Forum for the Study of Itch previously defined sensitive skin as a syndrome defined by the occurrence of unpleasant sensations (stinging, burning, pain, pruritus and tingling sensations) in response to stimuli that normally should not provoke such sensations. This additional paper focuses on the pathophysiology and the management of sensitive skin. Sensitive skin is not an immunological disorder but is related to alterations of the skin nervous system. Skin barrier abnormalities are frequently associated, but there is no cause and direct relationship. Further studies are needed to better understand the pathophysiology of sensitive skin – as well as the inducing factors. Avoidance of possible triggering factors and the use of well-tolerated cosmetics, especially those containing inhibitors of unpleasant sensations, might be suggested for patients with sensitive skin. The role of psychosocial factors, such as stress or negative expectations, might be relevant for subgroups of patients. To date, there is no clinical trial supporting the use of topical or systemic drugs in sensitive skin. The published data are not sufficient to reach a consensus on sensitive skin management. In general, patients with sensitive skin require a personalized approach, taking into account various biomedical, neural and psychosocial factors affecting sensitive skin.  相似文献   
39.
This evidence- and consensus-based guideline on the treatment of psoriasis vulgaris was developed following the EuroGuiDerm Guideline and Consensus Statement Development Manual. The first part of the guideline includes general information on the scope and purpose, health questions covered, target users and strength/limitations of the guideline. Suggestions for disease severity grading and treatment goals are provided. It presents the general treatment recommendations as well as detailed management and monitoring recommendations for the individual drugs. The treatment options discussed in this guideline are as follows: acitretin, ciclosporin, fumarates, methotrexate, adalimumab, apremilast, brodalumab, certolizumab pegol, etanercept, guselkumab, infliximab, ixekizumab, risankizumab, secukinumab, tildrakizumab and ustekinumab.  相似文献   
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