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1.
The use of mixtures of well-defined monoclonal antibodies may represent a step forward in the standardization of immunochemical assays. We developed and optimized working conditions for using such a mixture to determine apolipoprotein A-I in human sera by two independent techniques (electroimmuno- and immunonephelometric-assays). Six monoclonal antibodies, each addressed to distinct epitopes located at the surface of apolipoprotein A-I, were used in combination to permit a reproducible measurement of the protein, without prior delipidation of samples. Parallel standard curves for a high-density lipoprotein subfraction (HDL3, the primary standard) and a reference serum (the secondary standard) were obtained. Within- and between-run coefficients of variation were acceptable for both methods. Apolipoprotein A-I concentrations, as measured in 60 subjects selected to present a large range of apolipoprotein content by electroimmunoassay (y1) and immunonephelometric assay (y2) with monoclonal antibodies, compared well with those measured by the same techniques but with polyclonal antibodies (x): r1 = 0.96, r2 = 0.99; y1 = 1.19x - 0.11 g/L, y2 = 0.98x. Comparison of results obtained by electroimmunoassay and immunonephelometric assay performed with monoclonal antibodies was also good: r = 0.96; y2 = 1.08y1 + 0.13 g/L.  相似文献   
2.
Background: Intravenous infusion of lidocaine decreases postoperative pain and speeds the return of bowel function. The authors therefore tested the hypothesis that perioperative lidocaine infusion facilitates acute rehabilitation protocol in patients undergoing laparoscopic colectomy.

Methods: Forty patients scheduled to undergo laparoscopic colectomy were randomly allocated to receive intravenous lidocaine (bolus injection of 1.5 mg/kg lidocaine at induction of anesthesia, then a continuous infusion of 2 mg [middle dot] kg-1 [middle dot] h-1 intraoperatively and 1.33 mg [middle dot] kg-1 [middle dot] h-1 for 24 h postoperatively) or an equal volume of saline. All patients received similar intensive postoperative rehabilitation. Postoperative pain scores, opioid consumption, and fatigue scores were measured. Times to first flatus, defecation, and hospital discharge were recorded. Postoperative endocrine (cortisol and catecholamines) and metabolic (leukocytes, C-reactive protein, and glucose) responses were measured for 48 h. Data (presented as median [25-75% interquartile range], lidocaine vs. saline groups) were analyzed using Mann-Whitney tests. P < 0.05 was considered statistically significant.

Results: Patient demographics were similar in the two groups. Times to first flatus (17 [11-24] vs. 28 [25-33] h; P < 0.001), defecation (28 [24-37] vs. 51 [41-70] h; P = 0.001), and hospital discharge (2 [2-3] vs. 3 [3-4] days; P = 0.001) were significantly shorter in patients who received lidocaine. Lidocaine significantly reduced opioid consumption (8 [5-18] vs. 22 [14-36] mg; P = 0.005) and postoperative pain and fatigue scores. In contrast, endocrine and metabolic responses were similar in the two groups.  相似文献   

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The International Conference on Primary Health Care, meeting in Alma-Ata, in the Soviet Union, September 12, 1978, expressed the need for urgent action by all governments, all health and development workers and the world community, to protect and promote the health of all people of the world. The world was caught by the phrase which emerged from this conference, Health For All by the Year 2000 and many have examined the articles of the Alma-Ata declaration and tried to implement them in their corner of the world. This paper describes a community-based smoking-cessation program which was implemented in the province of Nova Scotia, Canada, during the years 1980–1984. Primary to this project was the belief that people have the right and the duty to participate individually and collectively in planning and implementing their health care. This paper describes one community's effort in putting this belief into practice.Carol Smillie, B.N. BE.d. M.S.c. is an Assistant Professor at the School of Nursing, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5, Katherine Coffin, BA, MEd is the Program Officer, Nova Scotia Office, Health Promotion Directorate Health and Welfare Canada, 5251 Duke Street, Halifax, Nova Scotia. Canada B3J 1P3. Kathryn Porter, B.A. (Gen)., is the Information and Education Coordinator, Nova Scotia Division Canadian Cancer Society. Brenda Ryan, B.A., M.B.A. is Program Evaluation Analysist, Nova Scotia Department of Health, 6088 Hollis Street, Halifax. Nova Scotia, Canada. This Project was funded by Health and Welfare Canada, Nova Scotia Department of Health, Nova Scotia Division Canadian Cancer Society, Requests for reprints should be addressed to: Professor Carol Smillie.  相似文献   
5.
To evaluate the role of the high-affinity monocyte receptor for lipopolysaccharide (LPS), CD14, in the process of tolerance to LPS, the human monocytic cell line Mono-Mac-6 was cultured in the absence or presence of different amounts of LPS. The kinetics of CD14 modulation in these cells showed an initial 4-day period characterized by increased cell-surface expression, rate of biosynthesis (peaking at 48 hr) and release of its soluble forms (sCD14) which correlated with the amount of LPS in the culture. At this time, tolerance to LPS was already established, as measured by tumour necrosis factor-alpha (TNF-alpha) induction, it was LPS dose dependent and persisted up to 15 days. LPS also reduced the cell proliferation rate in a dose-dependent manner. After 8 days and up to 15 days, the CD14 biosynthesis, cell-surface expression and release of sCD14 inversely correlated with the level of LPS in the culture. The 48-hr LPS-pretreated cells showed a slightly decreased CD14 affinity for LPS, a relative high number of CD14 molecules per cells, and desensitization also to a phorbol 12-myristate 13-acetate (PMA) challenge. An anti-CD14 monoclonal antibody (mAb) protected the cells from tolerization when added at the beginning of culture, as revealed by challenge with LPS and PMA. The data indicate that in this model tolerization to LPS (1) precedes CD14 down-modulation, (2) operates by alteration of the receptor affinity for LPS and by a mechanism which affects a protein kinase C (PKC)-dependent signalling pathway, and (3) that CD14 plays a critical role in the establishment of tolerance to LPS. In addition, analysis of the data suggests the existence of a PKC-independent signalling pathway for LPS tolerization and a CD14-independent mechanism for establishing tolerance.  相似文献   
6.
Investigation on the metabolism of CCK8 analogues by rat brain slices   总被引:2,自引:0,他引:2  
Degradation of Boc-CCK27-33 [Boc-Tyr(SO3H)-Met-Gly-Trp-Met-Asp-PheNH2) a fully potent analog of CCK8 was studied on synaptic plasma membranes from pig brain cortex. Characterization of the metabolites was performed by HPLC. This allowed to show the hydrolysis of the Asp-Phe bond by the neutral endopeptidase "enkephalinase", and the cleavages at the Met-Gly and Trp-Met bonds by PCMB sensitive enzymes. Similar results were observed using Boc(diNle28,31)-CCK27-33 as substrate. To investigate the biological relevance of these enzymes in the CCK8 metabolism, the degradation studies were performed on rat brain slices, with [3H]Boc(diNle28,31)CCK27-33 as substrate. Using these more physiological preparations i.e. striatal or cortex slices, the tritiated probe was cleaved at the Nle-Gly and Gly-Trp bonds. These degradation pathways were almost completely inhibited by PCMB, but in the striatum this inhibition process induced the appearance of a small peak corresponding to the action of enkephalinase. Taken together these results seem to indicate that thiol proteases play a crucial role in the CCK8 metabolism but that enkephalinase is virtually not involved.  相似文献   
7.
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.  相似文献   
8.
Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.  相似文献   
9.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
10.
Research into local anaesthetic mechanisms over the past few years has focused on two main issues. First, attention has focused on development of compounds with fewer side effects, better sensory/motor separation and longer duration of action; this has resulted in the introduction of ropivacaine and levobupivacaine into clinical practice. These agents have a lesser cardiotoxic effect than older compounds, and ropivacaine may in addition offer better sensory/motor separation. Several other compounds, including tonicaine and sameridine, are under investigation. In addition, the local anaesthetic properties of amitryptiline are being studied, and liposome encapsulation of local anaesthetics appears able to confer new pharmacokinetic properties on common drugs. Second, the molecular basis for several local anaesthetic actions that are not mediated by sodium channels has become a topic of interest. The mechanisms that underlie anti-inflammatory and antithrombotic actions are at present being unravelled. How local anaesthetics potentiate antitumour agents, protect neuronal tissue and prevent bronchial reactivity is less clear, but the potential clinical benefits of these effects deserve further exploration.  相似文献   
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