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31.
PURPOSE: One invariable hallmark of severe sepsis is generalized tissue "malperfusion" and hyperpermeability secondary to microcirculatory/capillary leakage. This review focuses on direct and/or indirect influences of norepinephrine, as a standard of care, and vasopressin, as an alternative vasoactive drug, on organ and tissue perfusion/permeability in severe sepsis. SOURCE: English and French language articles and books published between 1966 and 2005 were identified through a computerized Medline search using the terms "sepsis, permeability, norepinephrine and vasopressin". Relevant publications were retrieved and scanned for additional sources. PRINCIPAL FINDINGS: There are few randomized clinical trials comparing different vasopressors in sepsis; most available literature consists of clinical reports, animal experiments and occasional reviews. Based on the best current evidence from these sources, we describe the status of major organ perfusion/permeability in sepsis (i.e., the lung, the kidney, the heart, the intestine/gut) in the context of sepsis-induced organ dysfunction/failure. Potential and differential therapeutic effects of the vasopressors norepinephrine and arginine-vasopressin, in the setting of sepsis, are identified. CONCLUSIONS: In the treatment of sepsis, arginine-vasopressin exhibits organ-specific heterogeneity in vascular responsiveness, compared to norepinephrine. While norepinephrine is a current standard of care in sepsis, arginine-vasopressin shows promise for the treatment of septic shock.  相似文献   
32.
Cholesteryl sulfate is a normal constituent of human spermatozoa. The in vitro uptake of tritiated cholesteryl sulfate resulted in the labeling of all spermatozoa as demonstrated by light-microscope radioautography. The binding of the sterol sulfate was localized mainly in the head and midpiece. Radioautography at the level of the electron microscope revealed that the sterol sulfate is localized on the plasma membrane, mostly in the region of the acrosome. Further proof of this localization was obtained by selective dissolution of the plasma membrane and acrosome of the spermatozoa with low concentrations of Triton X-100. This treatment resulted in the simultaneous removal of tritiated cholesteryl sulfate bound to the spermatozoa. A hypothesis is presented concerning the role of cholesteryl sulfate as a membrane stabilizer and enzyme inhibitor during the maturation of spermatozoa in the epididymis. According to this hypothesis, the cleavage of the sulfate moiety within the female reproductive tract triggers a cascade of events leading to sperm capacitation and fertilization.  相似文献   
33.
Summary In order to evaluate the relation between balloon design (monofoil, trefoil) and valvular configuration, experimental aortic valvuloplasty was performed in four post-mortem hearts with calcific aortic stenosis of various morphology. The degree of obstruction of the aortic orifice was assessed by computed axial tomography during inflation of monofoil 15 and 19 mm and trefoil 3×12 mm balloon catheters. We also evaluated the hemodynamic repercussion of balloon inflation (fall in systolic aortic pressure) in four elderly patients with acquired aortic stenosis who underwent a percutaneous transluminal aortic balloon valvuloplasty, with stepwise increasing balloon sizes of 15 mm, 19 mm and 3×12 mm, as during ourin vitro experiments, and who underwent aortic valve replacement later on. In these patients, we correlated the anatomy of the excised aortic valves with the retrospective analysis of aortic pressure curves recorded during previous valvuloplasty procedures.Our experimental and clinicopathological observations showed that the degree of obstruction of the aortic orifice in post-mortem specimens and the tolerance to balloon inflation in live patients are dependent of the valvular configuration. Although trefoil balloons have the theoretical advantage to avoid complete obstruction of the aortic orifice during inflation, we observed that in presence of a tricuspid configuration, they could be potentially more occlusive than monofoil balloons since each of the 3 individual components of the trefoil balloon occupied the intercommissural spaces while inflated. However, they offered more residual free space when inflated in aortic valves with a bicuspid configuration (i.e. congenitally bicuspid valves or tricuspid valves with one fused commissure).In our opinion, these observations are relevant, since degenerative disease of the aortic valve (i.e. tricuspid valve without commissural fusion) is now recognized as the most common etiology of aortic stenosis in the elderly.Abbreviations AS aortic stenosis - AVA aortic valve area - PTAV percutaneous transluminal aortic balloon valvuloplasty A video supplement to this article has been published in Cardiac Imaging Video Journal volume 2, nr. 4, 1989, see Reference 29.  相似文献   
34.

Objectives

A two-stage, single-arm, phase II study was conducted to assess the effectiveness and safety of an epigallocatechin gallate (EGCG)-enriched tea drink, the double-brewed green tea (DBGT), as a maintenance treatment in women with advanced stage serous or endometrioid ovarian cancer (clinicaltrials.gov, NCT00721890).

Methods

Eligible women had FIGO stage III-IV serous or endometrioid ovarian cancer. They had to undergo complete response after debulking surgery followed by 6 to 8 cycles of platinum/taxane chemotherapy at the Centre Hospitalier Universitaire de Québec. They all had to drink the DBGT, 500 mL daily until recurrence or during a follow-up of 18 months. The primary endpoint was the absence of recurrence at 18 months. Statistical analyses were done according to the principle of intention to treat. Using a two-stage design, the first stage consisted of 16 enrolled patients. At the end of the follow-up, if 7 or fewer patients were free of recurrence, the trial stopped. Otherwise, accrual would continue to a total of 46 patients.

Results

During the first stage of the study, only 5 of the 16 women remained free of recurrence 18 months after complete response. Accordingly, the clinical trial was terminated. Women's adherence to DBGT was high (median daily intake during intervention, 98.1%, interquartile range: 89.7–100%), but 6 women discontinued the intervention before the end of their follow-up. No severe toxicity was reported.

Conclusions

DBGT supplementation does not appear to be a promising maintenance intervention in women with advanced stage ovarian cancer after standard treatment.  相似文献   
35.
36.
Borderline personality disorder (BPD) has been associated with maladaptive cognitive processes including dysfunctional attitudes and a negative attribution style. Comorbid insomnia affects the course of multiple psychiatric disorders, and has been associated with the absence of recovery from BPD. Because dysfunctional beliefs and attitudes are common among patients with insomnia, the purpose of this study was to evaluate the association between maladaptive sleep-related cognitions and recovery status (symptomatic remission plus good concurrent psychosocial functioning) in patients with BPD. Two hundred and twenty three BPD patients participating in the McLean Study of Adult Development (MSAD) were administered the Dysfunctional Beliefs and Attitudes about Sleep questionnaire (DBAS-16) as part of the 16-year follow-up wave. Maladaptive sleep cognitions were compared between recovered (n=105) and non-recovered (n=118) BPD participants, in analyses that adjusted for age, sex, depression, anxiety, and primary sleep disorders. Results demonstrated that non-recovered BPD patients had significantly more severe maladaptive sleep-related cognitions as measured by the overall DBAS-16 score. These results demonstrate an association between dysfunctional beliefs and attitudes about sleep and recovery status among BPD patients. Further research is warranted to evaluate treatments targeted towards maladaptive sleep-related cognitions, and their subsequent effects on the course of BPD.  相似文献   
37.
Speech-controlled generation of radiology reports   总被引:1,自引:0,他引:1  
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.  相似文献   
38.
Samoszuk  MK; Espinoza  FP 《Blood》1987,70(2):597-599
Eosinophil granules are intensely autofluorescent when excited by green light. To determine if eosinophils degranulate in the bone marrows of patients with a variety of diseases, we used green light epifluorescence microscopy to examine deparaffinized and dezenkerized sections of 49 bone marrow core biopsies. In 14 of the biopsies, there was striking extracellular deposition of intensely autofluorescent eosinophil granules in addition to numerous intact eosinophils. Among the 14 specimens with extracellular autofluorescence were seven cases of leukemia, four cases of non-Hodgkin's lymphoma, two cases of myelofibrosis, and one case of pancytopenia with eosinophilia. In the remaining 35 specimens, only intact eosinophils were identifiable. There was no extracellular autofluorescence in three normal marrows, four marrows from AIDS patients, or three biopsies from patients with idiopathic thrombocytopenic purpura (ITP). We conclude that green light epifluorescence microscopy identifies extracellular deposits of eosinophil granules in bone marrow biopsies of some neoplastic disorders and in diseases associated with reticulin fibrosis.  相似文献   
39.
At the Department of Radiation Oncology, Westmead Hospital, between 1980 and 2000, 60 patients with squamous cell carcinoma of anal canal or margin (including 15 with Stage IIIA or IIIB) were treated radically; 55 received chemoradiation (89% were prescribed mitomycin C and 5‐fluorouracil). Five‐year overall survival was 64% (95% confidence interval (CI): 48–79%), with a median survival of 9.75 years (median follow up 5.6 years, range 5 months to 22.5 years). Ten patients have died of disease. At 2 years the local control rate was 86%, and colostomy‐free survival was 83%. Relapse after 2 years was uncommon. Tumour size was the main factor driving outcomes, especially survival. Patients with larger tumours (T > 4 cm) had a hazard ratio for survival of 5.7 (95% CI: 1.8–17). Fourteen (24%) patients experienced treatment interruptions as a result of acute toxicity, including one death from neutropoenic sepsis. Seven (12%) patients, in total, experienced one or more late toxicities, grade 3 or above, including four women (all postmenopausal) who developed a radiation‐induced bone injury. Most patients with anal cancer can expect to retain a functional sphincter after chemoradiation/radiation. Further studies are in progress to determine the optimal chemoradiation protocol.  相似文献   
40.
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