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121.
The reinforcing effects of intravenous (I.V.) ethanol were examined in C57BL/6J (C57) mice with a conditioned-place-preference (CPP) paradigm. Before CPP testing, adult mice underwent jugular catheterization. On the following day, subjects were acclimated to a two-compartment CPP chamber. A 15-min nondrug pretest was conducted to determine compartment preference. For the treatment group, I.V. ethanol [30% (v/v), 3.4 microl/min, 25 min] was paired with the nonpreferred compartment, whereas I.V. saline was paired with the preferred compartment. The control group received I.V. saline in both compartments. Two conditioning sessions were conducted per day (0900 and 1500), and the order of the infusions was counterbalanced across subjects. The drug-free posttest was identical to the pretest, except that it occurred on the day after the final drug/compartment pairing. The entire procedure required 6 days. After just two pairings with ethanol, with a cumulative ethanol dose of only 0.82 g/kg/day, significant CPP was noted in the treatment group, whereas no change in compartment preference was noted for the control group. A separate group of C57 mice were trained to discriminate intraperitoneal ethanol (1.5 g/kg) from saline using a two-lever drug discrimination paradigm. After training was complete, these mice also underwent jugular catheterization. Substitution testing was conducted with I.V. ethanol [30% (v/v), 6.4 microl/min, 12 min] and saline. The results indicate that the subjective effects of ethanol did not differ according to the route of administration. Together, these experiments provide evidence that ethanol is rewarding for C57 mice, as indexed by ethanol CPP, and that the subjective effects of intravenously and intraperitoneally administered ethanol are similar.  相似文献   
122.
Cytomegalovirus (CMV) antigenemia was directly detected in polymorphonuclear leukocytes (PMNLs) from transplant recipients by using flow cytometry (FC). Two fixation and permeabilization methods and seven anti-CMV monoclonal antibodies (MAbs) were evaluated. 1C3, SL20, and NEA-9221 MAbs were more efficacious. The antigenemia detection threshold of FC was 0.05% positive PMNLs, and percentages correlated well with DNA viral load and the appearance of clinical symptoms.  相似文献   
123.
Gerontological nurses are dynamic individuals who recognize the necessary changes needed to reform a biotechnology-driven health care system to become a relationship-centered, care-driven healing system with elders. They must continue to take action to enhance caring and healing at personal levels and in various professional levels of clinical practice and health care reform. As gerontological nurses pursue personal, clinical, educational, and research approaches to holistic nursing and caring-healing modalities, they increase their knowledge and skills of holism and the complex body-mind-spirit interconnections, and provide relationship-centered care (Tresolini, 1994). Gerontological nurses then truly blend the art and science of caring with elders, and lead to a deeper understanding of healing as a lifelong journey into wholeness (Achterberg, Dossey & Kolkmeier, 1994).  相似文献   
124.
Several plant ribotoxins, including gelonin, were reported to have additional weak nuclease activities on supercoiled DNA. The potential contribution of this activity to their cytotoxicity has not been given serious consideration due to concerns about contaminating nucleases in the protein preparations. We now report the degradation of single-stranded DNA by preparations of native plant gelonin and recombinant gelonin produced in E. coli. The DNase activity of both preparations is similarly modulated by zinc. An SDS-PAGE DNase assay identifies gelonin as the polypeptide responsible for deoxyribonuclease activity.  相似文献   
125.
A wide variety of lasers provides the plastic surgeon with treatment options that were not available previously. Appropriate, safe use of lasers complements the many therapeutic treatment options available to plastic surgeons. Lasers have introduced a new therapeutic modality. Because of the ways the skin and its defects may be altered with lasers, they will be an increasingly important part of plastic surgery.  相似文献   
126.
Angiogenesis plays an important role in breast cancer growth and metastasis. Multiple adhesion molecules have been shown to perform critical functions in the process of angiogenesis. In this study, we analyzed 15 benign and 22 malignant estrogen-receptor-negative and estrogen-receptor-positive breast specimens for the presence of the endothelial cell adhesion molecules E-selectin and P-selectin. We found that E-selectin's expression was increased in the malignant breast tumors compared with their benign counterparts (23.86% of blood vessels versus 2.47%; P = 0.0005). Furthermore, E-selectin staining was found to be significantly increased in the estrogen-receptor-negative carcinomas compared with the estrogen-receptor-positive ones (P = 0.005). In vitro findings strongly correlated with the in vivo findings and showed a higher degree of E-selectin induction in endothelial cells exposed to conditioned media from estrogen-receptor-negative breast cancer cell lines than from estrogen-receptor-positive ones. The degree of E-selectin induction correlated with the amount of interleukin-1 alpha in the tumor-conditioned media. Neutralizing antibodies to interleukin-1 alpha significantly inhibited the E-selectin expression in endothelial cells exposed to tumor-conditioned media. The results indicate that the endothelial E-selectin expression during angiogenesis is related to breast carcinoma progression in vivo and that this component of angiogenesis may be due directly to tumor-cell-secreted interleukin-1 alpha.  相似文献   
127.
128.
OBJECTIVE: To evaluate the histopathologic changes that occur in human small intestine or time when preserved in Viaspan organ preservation solution. DESIGN: Short segments of human small intestine were placed in standard organ preservation solution (Viaspan) and stored in conditions that mimic the clinical situation associated with clinical organ procurement, preservation, and transplantation. The intestinal segments were removed at sequential time points and placed in 10% formalin. Specimens underwent histopathologic examination to determine time-related changes. SPECIMENS: Short intestinal segments were obtained from seven multiorgan cadaver donors. Specimens were obtained in a way that exactly mimicked small intestinal organ retrieval. RESULTS: Small intestinal histology remained normal for the first 6 hours. After 6 hours, vacuolar separation began to occur between the epithelium and the basement membrane in the upper half of the villi. After 9 hours of cold preservation, epithelial detachment extended deep into the crypts with occasional shedding of cells and villi. CONCLUSIONS: Currently used small intestinal preservation using Viaspan results in considerable histopathologic changes in human jejunum after 9 hours of cold storage. The histopathologic pattern appears normal for the first 6 hours and suggests that preservation times should be limited to this time period when possible.  相似文献   
129.
Circulating anticoagulants are a major risk factor for thrombotic problems (eg, myocardial infarction, stroke) and pregnancy complications. The authors present a retrospective survey of anticardiolipin antibody and lupus anticoagulant in 200 consecutive patients presenting to their office.  相似文献   
130.
The purpose of this study was to determine the satisfaction and fringe benefits of Texas dental hygienists and compare the data to a recent national study. A blind survey was forwarded to 5,294 active, licensed dental hygienists to obtain data for Texas. Responses were received from 2,172 dental hygienists, a 41 percent response rate. The greatest number of responses came from the larger cities in Texas: Dallas, Houston, Austin, and San Antonio. Fifty-eight percent of Texas hygienists receive paid vacation, 25 percent medical insurance, 37 percent sick pay, and 26 percent receive some type of retirement. Nationally, the figures are higher. The survey also sought to determine satisfaction levels. Most dental hygienists are satisfied with their salary (65%), their career (85%), and feel secure in their employment (92%), while only 46 percent are satisfied with benefits. The survey results are inconclusive for hygienists' in the state of Texas based on the 41 percent response rate. Practical information may assist employers in recruitment and retention of a dental hygienist into the practice.  相似文献   
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