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The effects of a constant infusion of total parenteral nutrition on the histamine content of the hypothalamus was studied in adult male rats. Histamine content of the stomach, kidney, liver, and heart was also determined. The relationship between tissue histamine levels and duration of the infusion was examined. Rats receiving intravenous infusions of total parenteral nutrition had significantly higher (p less than 0.001) histamine levels in the hypothalamus than did orally-fed control rats. No difference was observed in the histamine level in the remainder of the brain. Animals receiving parenterally infused nutrient solutions had a higher histamine content in the kidneys but lower histamine levels in the stomach than did the control rats. No changes in the histamine content of liver or heart were observed. It appears that increases in histamine levels in the kidney and hypothalamus of rats given total parenteral nutrition persist up to 5 days and 9 days, respectively. The mechanisms responsible for and the consequences of the alterations of histamine content of these tissues remain to be established.  相似文献   
3.
Highly resolving two-dimensional gels for protein sequencing.   总被引:6,自引:3,他引:3       下载免费PDF全文
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   
4.
This article describes the development of the Ethical Principles and Guidelines for Family Scientists that the National Council on Family Relations Board of Directors unanimously approved. Furthermore, it discusses the importance of ethics education for family professionals and provides suggestions for educators. Finally, the ethical principles and guidelines are delineated. We argue that the development of a scholarship on ethics education is important for current and future family scientists.  相似文献   
5.
Summary An inexpensive instrument has been described that may be used to eliminate noise in low-level nerve recordings. This electronic manipulation of such signals increases the reliability of digitising or illustrating neural events while eliminating ambiguous noise levels.  相似文献   
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Objectives

Although hospital clinicians strive to effectively refer patients who require post-acute care (PAC), their discharge planning processes often vary greatly, and typically are not evidence-based.

Design

Quasi-experimental study employing pre-/postdesign. Aimed at improving patient-centered discharge processes, we examined the effects of the Discharge Referral Expert System for Care Transitions (DIRECT) algorithm that provides clinical decision support (CDS) regarding which patients to refer to PAC and to what level of care (home care or facility).

Setting and participants

Conducted in 2 hospitals, DIRECT data elements were collected in the pre-period (control) but discharging clinicians were blinded to the advice and provided usual discharge care. During the postperiod (intervention), referral advice was provided within 24 hours of admission to clinicians, and updated twice daily. Propensity modeling was used to account for differences between the pre-/post patient cohorts.

Measures

Outcomes compared between the control and the intervention periods included PAC referral rates, patient characteristics, and same-, 7-, 14-, and 30-day readmissions or emergency department visits.

Results

Although 24%–25% more patients were recommended for PAC referral by DIRECT algorithm advice, the proportion of patients receiving referrals for PAC did not significantly differ between the control (3302) and intervention (5006) periods. However, the characteristics of patients referred for PAC services differed significantly and inpatient readmission rates decreased significantly across all time intervals when clinicians had DIRECT CDS compared with without. There were no differences observed in return emergency department visits. Largest effects were observed when clinicians agreed with the algorithm to refer (yes/yes).

Conclusions/Implications

Our findings suggest the value of timely, automated, discharge CDS for clinicians to optimize PAC referral for those most likely to benefit. Although overall referral rates did not change with CDS, the algorithm may have identified those patients most in need, resulting in significantly lower inpatient readmission rates.  相似文献   
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Preliminary research indicates that hypnotically induced deafness may reduce the speech inhibiting effects of delayed auditory feedback (DAF). The present experiment was conducted to compare real and simulating hypnotic Ss with respect to the improvement in speech consequent to the suggestion of deafness. Results indicate very similar improvements of DAF speech for both real and simulating Ss. An incidental finding is that real Ss have longer simple reading times under hypnosis than do simulating Ss in this experiment.  相似文献   
10.
Accelerated idioventricular rhythm (AIVR) is found most commonly in the presence of underlying heart disease. It is characterized by acceleration of a latent pacemaker that normally depolarizes slowly. We describe a 30-year-old man who was found to have episodes of accelerated idioventricular rhythm (AIVR) on cardiac monitoring during elective orthopedic surgery. Noninvasive evaluation including two-dimensional echocardiography was unremarkable. No late potentials were detected on a signal-averaged electrocardiogram. During an exercise tolerance test, AIVR was suppressed as heart rate increased. A 24-h Holter monitor revealed that the AIVR rate was consistently 73-76 beats/min, which appeared whenever the sinus rate slowed to this level. The patient has been asymptomatic, and the rhythm has persisted at least through a 5-month follow-up period.  相似文献   
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