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51.
In a recent issue of Critical Care, Brandt and colleagues report the effects of a 'liberal' fluid loading protocol compared to a more 'restrictive' protocol on hemodynamics and mortality in pigs in which septic shock had been induced. It appears that the former protocol was associated with higher mortality in spite of improved hemodynamics compared to the latter. The results of the paper are discussed here in view of the scope and mechanisms of these findings. With regard to fluid resuscitation, they indicate that too much of an otherwise good thing is harmful, even if overhydration and edema formation seem to have been prevented. They also do not exclude a specific toxic effect of the larger volumes of hydroxyethyl starch in the 'liberal' strategy. The precise nature of a toxic effect remains obscure, however, but may involve the kidneys.  相似文献   
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PURPOSE: The aim of this study was to determine the incidence of local pelvic recurrence of carcinoma of the rectum and rectosigmoid (tumors where the lower edge is 18 cm or less from the anal verge) in a consecutive series of patients operated on by a single surgeon. All patients underwent curative anterior resection and a formal anatomic dissection of the rectum where mobilization was achieved through a principally careful blunt manual technique along fascial planes, preserving an oncologic package. METHOD: During the period April 1986 to December 1997, 157 consecutive anterior resections for carcinoma of the rectum and rectosigmoid were performed by one surgeon (ALP). One hundred thirty-eight (87.9 percent) were curative, and 19 (12.1 percent) were palliative. The mean follow-up period was 46±31.6 (range, 2–140) months. Data were retrospectively collated and computer coded by an independent contracted medical research team. Follow-up data were available on all patients. RESULTS: Four (3.1 percent) of the 131 patients undergoing curative anterior resection had local recurrence. Local recurrences occurred between 16 and 38 months from the time of resection, and the cumulative risk of developing local recurrence at five years was 5.2 percent. All tumors in which pelvic recurrence occurred were high grade, and the probability of developing local recurrence at five years for this group was 13.9 percent, which is significantly higher compared with patients who had average or low-grade tumors (P=0.01). The probability of developing local recurrence at five years for Stage I tumors was 0, Stage II was 5.9 percent, and Stage III was 8.9 percent. In addition, there was a significantly higher incidence of local recurrence in the group of patients undergoing ultralow anterior resection (between 3 and 6 cm from the anal verge) as compared with patients undergoing low or high anterior resection (P=0.03). Local recurrence developed in 3 of 28 (10.7 percent) patients having ultralow anterior resection, 1 of 57 (1.8 percent) patients having low anterior resection (between 6 and 10 cm from the anal verge), and no patients having high anterior resection (above 10 cm from the anal verge). The clinical anastomotic leak rate for curative anterior resection was 7 of 131 patients (5.3 percent). Thirty-seven of the 131 (28.2 percent) required a proximal defunctioning stoma; 35 (41.2 percent) of these were established for low or ultralow anterior resections and 2 for high anterior resection. The overall five-year cancer-specific survival rate of the entire group of 131 patients was 81.8 percent, and the overall probability of being disease free at five years including both local and distal recurrence was 72.9 percent. Three local recurrences occurred in the 101 patients (77 percent) who did not receive any form of adjuvant therapy. One local recurrence occurred in the 18 patients (13.7 percent) who had adjuvant chemoradiation. No recurrence occurred in the 12 patients (9.2 percent) who had adjuvant chemotherapy alone. CONCLUSION: Curative anterior resection for carcinoma of the rectum and rectosigmoid with principally blunt dissection of the rectum in this study is associated with a 3.1 percent incidence and a 5.2 percent probability at five years of developing local recurrence. Evidence from this study indicates that, as with sharp pelvic dissection, a low incidence and probability of local recurrence can be achieved by a principally blunt mobilization technique through careful attention to preservation of fascial planes in the pelvis and removal of an oncologic package with selective rather than routine adjuvant or neoadjuvant chemoradiation.Supported by a research grant from the Cabrini Clinical Education and Research Foundation.Read at The American Society of Colon and Rectal Surgeons' 100th Anniversary and Tripartite Meeting, Washington, D.C., May 1 to 6, 1999.  相似文献   
53.

Background  

The association of Chlamydia pneumoniae with atherosclerosis is controversial. We investigated the presence of C. pneumoniae and other Chlamydia spp. in atheromatous carotid artery tissue.  相似文献   
54.
INTRODUCTION: This study was undertaken to identify prehospital system and management deficiencies and preventable deaths between 01 January 1997 and 31 December 1998 in 243 consecutive Victorian road crash victims with fatal outcomes. METHODS: The complete prehospital and hospital records, the deposition to the coroner, and autopsy findings were evaluated by computer analysis and peer group review with multidisciplinary discussion. RESULTS: One-hundred eighty-seven (77%) patients had prehospital errors or inadequacies, of which 135 (67%) contributed to death. Three-hundred ninety-four (67%) related to management and 130 (22%) to system deficiencies. Technique errors, diagnosis delays, and errors relatively were infrequent. One of 24 deaths at the crash scene or en route to hospital was considered to be preventable and two potentially preventable. CONCLUSION: The high prevalence of prehospital deficiencies has been addressed by a Ministerial Task Force on Trauma and Emergency Services and followed by the introduction of a new trauma care system in Victoria.  相似文献   
55.
Objectives. We studied the duration and prognostic significance of atrial arrhythmias in the denervated transplanted heart, specifically the occurrence of atrial fibrillation in the absence of vagal modulation.

Background. Substantial animal data indicate that vagally induced dispersion of atrial refractoriness plays a central role in the induction and maintenance of atrial fibrillation.

Methods. We studied the occurrence of atrial arrhythmias in the denervated hearts of 88 consecutive orthotopic transplantations in 85 patients by means of continuous telemetry and all available electrocardiographic tracings.

Results. Fifty percent of recipients (44 of 88) developed at least one atrial arrhythmia. Atrial fibrillation occurred 23 times (21 recipients), atrial flutter 39 times (26 recipients), ectopic atrial tachycardia 3 times (3 recipients) and supraventricular tachycardia 18 times (11 recipients). The number of atrial fibrillation and atrial flutter episodes did not differ (23 vs. 39, p = 0.072), but the fibrillation (37.0 ± 10 vs. 6.6 ± 3.6 h, p = 0.014). Atrial fibrillation was associated with an increased risk of subsequent death (10 of 21 recipients with vs. 15 of 67 without atrial fibrillation, risk ratio 3.15 ± 0.18, p = 0.005 by Cox proportional hazards model). All 5 recipients who developed “late” atrial fibrillation (>2 weeks after transplantation) died versus 5 of 16 who developed atrial fibrillation within the first 2 weeks (p = 0.007). Causes of death included rejection (three recipients), allograft failure (two recipients), infection (three recipients) and multiorgan failure (two recipients). Atrial fibrillation was not associated with age, gender, ischemic time, reason for transplantation, echocardiographic variables, invasive hemodynamic variables or biopsy grade. Mean time from atrial arrhythmia to echocardiography was 2.7 ± 3.3 days; that to biopsy was 4.8 ± 6.3 days. Atrial flutter was not associated with subsequent death. Only 7 (15.9%) of 44 recipients demonstrated moderate or severe allograft rejection at the time of the arrhythmia.

Conclusions. Atrial arrhythmias occur frequently in the denervated transplanted heart, often in the absence of significant rejection. Late atrial fibrillation may be associated with an increased all-cause mortality.  相似文献   

56.
Acetylcholine may be released from gallbladder intrinsic nerves in response to cholecystokinin stimulation. This study characterized metabolites of [14C]choline produced in the gallbladder and released during incubation, with or without cholecystokinin-octapeptide. Radiolabeled [14C]choline was applied to the mucosal or muscle surface of intact guinea pig gallbladders in an organ bath. After radiolabeling, gallbladders were incubated with or without the contractile agonist cholecystokinin-octapeptide. Metabolites of [14C]choline were identified in gallbladder tissue and incubation buffers using HPLC and thin-layer chromatography. The major metabolites of [14C]choline were betaine and phosphocholine. [14C]Phosphocholine was incorporated slowly into [14C]phosphatidylcholine. [14C]Choline was released into buffers during incubation. [14C]Acetylcholine constituted less than 1% of radiolabel in the gallbladder. There was no identifiable [14C]acetylcholine released in buffers. Cholecystokinin-octapeptide did not affect choline metabolism. These studies showed that choline in the gallbladder is metabolized along pathways similar to those in the liver. Gallbladders released mostly choline, rather than acetylcholine, even during hormonally induced contraction.This project was supported by the Research and Development Office of the Department of Veterans Affairs.  相似文献   
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BACKGROUND Previous studies suggest that patients who are more involved in their medical care have better outcomes. OBJECTIVES We sought to compare health care processes and outcomes for patients with HIV based on their preferred level of involvement in health decisions. DESIGN Cross-sectional analysis of audio computer-assisted interviews with patients at an urban HIV clinic. PATIENTS One thousand and twenty-seven patients awaiting an appointment with their primary care provider. MEASURES Patients were asked how they preferred to be involved in decisions (doctor makes most or all decisions, doctor and patient share decisions, patient makes all decisions). We also asked patients to rate the quality of communication with their HIV provider, and their self-reported receipt of and adherence to HAART. RESULTS Overall, 23% patients preferred that their doctor make all or most decisions, 63% preferred to share decisions with their doctor, and 13% preferred to make all final decisions alone. Compared to patients who prefer to share decisions with their HIV provider, patients who prefer that their provider make all/most decisions were significantly less likely to adhere to HAART (OR [odds ratio] 0.57, 95% CI 0.38–0.86) and patients who preferred to make decisions alone were significantly less likely to receive HAART or to have undetectable HIV RNA in unadjusted analyses (OR 0.52, 95% CI 0.31–0.87 for receipt of HAART; OR 0.64, 95% CI 0.44–0.95 for undetectable HIV RNA). After controlling for potentially confounding patient characteristics and differences in patient ratings of communication quality, patients who preferred that their provider make all/most decisions remained significantly less likely to adhere to HAART (OR 0.58, 95% CI 0.38–0.89); however, the associations with receipt of HAART and undetectable HIV RNA were no longer significant (OR 0.60, 95% CI 0.34–1.05 for receipt of HAART; OR 0.80, 95% C.I 0.53–1.20 for undetectable HIV RNA). CONCLUSIONS Although previous research suggests that more patient involvement in health care decisions is better, this benefit may be reduced when the patient wants to make decisions alone. Future research should explore the extent to which this preference is modifiable so as to improve outcomes.  相似文献   
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