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101.
D A Conetta L G Christie C J Pepine W W Nichols C R Conti 《Catheterization and cardiovascular diagnosis》1979,5(2):135-143
Because no accurate and readily applied method exists for continuous recording of left ventricular cavity dimensions and wall motion in man, we designed a catheter-mounted echocardiographic probe. The purpose of this report is to describe the instrumentation, technique, limitations, complications and preliminary observations employing the probe in humans. The echo transducer built into a cardiac allowed positioning in the right heart under fluoroscopy. The echo signals permitted continuous left ventricular cavity measurements at rest and during maneuvers. Our results suggest that intracardiac echo may be able to provide clear definition of motion patterns of the mitral valve and left ventricular walls. The ultrasonic catheter is an instrument that potentially offers a new technique for continuous monitoring of left ventricular size and motion. 相似文献
102.
103.
The frequency of isolation of enterococci from surgical patients has increased significantly during the past decade, although the role of these organisms as pathogens in mixed infections remains a mystery. Bacteremia and other infections in which enterococci are the only pathogens frequently result in high morbidity and mortality among patients unless specific antimicrobial therapy is initiated promptly. Debate continues concerning the necessity for treatment with such agents when this organism is isolated as a component of a polymicrobial infecting flora. Our recent data indicate that enterococci are rarely isolated in postoperative infections after penetrating abdominal trauma if no gastrointestinal perforation has occurred. However, they were found in 56% of postoperative infections of patients with gastrointestinal perforation. In contrast, enterococci were isolated in only 9% of cultures of specimens from patients with secondary suppurative peritonitis. The occurrence of superinfection after therapy with a cephalosporin appears to be an important factor in this finding. Future studies are necessary to evaluate the efficacy of antibiotic treatment of enterococcal infections and to assess the need for prophylaxis against enterococci. 相似文献
104.
Efficacy of parenteral antibiotics in the treatment of experimentally induced intraabdominal sepsis 总被引:1,自引:0,他引:1
An experimental model of intraabdominal sepsis closely approximating the disease in humans was used to evaluate the efficacy of clindamycin, tobramycin, cephalothin, and cefamandole, alone and in combination, in reducing both early mortality due to peritonitis and the subsequent development of abscesses. Sepsis was induced in rats by intraperitoneal placement of gelation capsules containing various amounts of human stool inoculum. Ninety percent of the untreated animals given a high inoculum died of peritonitis within 24 hr, and the survivors showed significant intraabdominal abscesses at the time of sacrifice. Animals treated with clindamycin-tobramycin, cephalothin-tobramycin, cefamandole-tobramycin, or cefamandole alone in the high-inoculum group showed a significant decrease in early mortality. Only animals treated with clindamycin-tobramycin, however, had a significantly increased cure rate (survival with no abscess present at time of sacrifice). In low-inoculum groups, several antibiotics alone or in combination significantly decreased mortality and increased cure rates. The selective use of antibiotics is critical in the treatment of severe forms of intraabdominal sepsis. 相似文献
105.
Insulin-induced hypoglycemia is a metabolic stress that stimulates secretion of adrenocorticotropic hormone (ACTH) and cortisol in a number of animal species. Dexamethasone is a potent synthetic glucocorticoid that suppresses the secretion of ACTH and cortisol. Both ACTH and cortisol exhibit complex secretory patterns demonstrating ultradian and circadian rhythms. This work investigated the pattern of ACTH and cortisol response to hypoglycemia in goats and the effect of dexamethasone on this response. Five goats were pretreated with dexamethasone (0.1 mg/kg) and 5 with saline. Blood samples were taken every 2 min for 60 min before and 60 min after administration of insulin (2.5 IU/kg, i.v.). Immunoreactive ACTH and cortisol were measured in all samples and glucose in selected samples. Data sets were analyzed for significant pulses with the Cluster Analysis program. Complete data sets were compared as well as those for each 30-min interval. Plasma glucose was lower than preinsulin levels at 10 min, declined rapidly between 10 and 30 min, and remained low 30-60 min after insulin injection in both treatment groups. Controls showed a rapid rise in ACTH and cortisol beginning 30 +/- 10 min postinsulin. The increase in mean plasma hormone levels during hypoglycemia was predominantly due to an increase in amplitude of secretory pulses for ACTH and cortisol compared with the 30 min before insulin. Dexamethasone significantly lowered mean ACTH and cortisol levels and prevented alteration in plasma ACTH and cortisol secretion during hypoglycemia but did not totally ablate pulsatile activity of either hormone. The amplitude of ACTH and cortisol pulses was significantly decreased by dexamethasone treatment. The frequency of cortisol but not ACTH pulses was also significantly decreased.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
106.
R Burns L Nichols E Calkins S Blackwell D Pragay 《Journal of the American Geriatrics Society》1986,34(11):781-786
Nutritional assessment parameters were studied in a sample of 132 community-living well elderly. Results are presented for biochemical parameters of serum albumin, hemoglobin, and total lymphocyte count and anthropometric parameters of height, weight, mid-arm circumference, and triceps skinfold. The data show that, although there are some differences between age groups (young-old and old-old), all values remain well within normal limits established for younger individuals. 相似文献
107.
108.
Feldstein AC Nichols GA Smith DH Rosales AG Perrin N 《Journal of general internal medicine》2008,23(9):1339-1345
BACKGROUND Limited community-based data describe weight change after diabetes diagnosis.
OBJECTIVE To evaluate weight change patterns and associations in the 1st year after diabetes mellitus type 2 diagnosis.
DESIGN Retrospective cohort study.
PARTICIPANTS Patients aged 21–75 with diabetes mellitus type 2 diagnosed between 1 January 1997 and 31 December 2004, identified from electronic
medical records in Kaiser Permanente Northwest, a health maintenance organization. Eligible patients met weight measurement
criteria (a baseline and three additional weight measurements) and did not have a condition associated with unintentional
weight change (n = 4,135).
MEASUREMENTS We estimated 12-month patient weight trajectories using growth curve analyses, grouped similar trajectories using cluster
analysis, and compared characteristics among groups.
RESULTS The four weight trajectory groups were “higher stable weight” (n = 757; 18.3%), “lower stable weight” (n = 2,236; 54.1%),
“weight gain” (n = 664; 16.0%), and “weight loss” (n = 478; 11.6%). After adjustments, members of the weight-loss group were
more likely than those in the weight-gain group to be older, female, take fewer medications, have had nutritionist visits,
and have a lower mean HbA1c. Those in the weight-loss group were less likely to be in a race group at higher risk for obesity, have depression or dyslipidemia,
or have taken >30 days of a sulfonylurea alone or with metformin.
CONCLUSIONS A small-but-substantial group of patients had a mean weight trajectory that included a clinically significant weight loss.
Weight-loss trajectories were strongly associated with better glycemic control when compared to weight gain. Patients with
certain characteristics may need more support for weight loss.
This study was supported by grant no. R21 DK073546–02 (Weight in Secondary Prevention) from the National Institute of Diabetes
and Digestive and Kidney Diseases 相似文献
109.
110.
S. A. Pilkington R. Bhome R. E. Welch F. Ku C. Warden S. Harris J. Hicks C. Richardson T. C. Dudding J. S. Knight A. T. King A. H. Mirnezami N. E. Beck P. H. Nichols K. P. Nugent 《Techniques in coloproctology》2018,22(7):545-551