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101.
Eighteen patients with chemodectomas arising in temporal bone structures were evaluated and treated at the University of Florida. Seventeen patients have each been followed a minimum of 3 years. Patients were retrospectively staged as having "local" or "advanced" disease, depending on the presence or absence of bone destruction and/or cranial nerve involvement. Fourteen of the patients received radiation therapy as all or part of their therapy; 6 patients were treated with radiation therapy alone, 3 patients were irradiated immediately postoperatively for residual disease, and 5 patients had radiation therapy for recurrence after operation. They were treated with cobalt-60 radiation with doses ranging from 3760 to 5640 rad. All irradiated patients demonstrated evidence of tumor regression, and none have had tumor recurrence with followup of 3-12 years. Of the 8 patients with cranial nerve paralysis prior to therapy, 5 had return of function of 1 or more cranial nerves. One of 6 patients treated initially with radiation therapy had a complication, while 6 of 8 patients irradiated postoperatively had complications. None of the complications were fatal. Three patients treated by operation for early disease limited to the hypotympanum had the disease controlled for 11-12 years. Guidelines for the selection of initial therapy are discussed.  相似文献   
102.
A retrospective analysis of reports of medication administration errors over a period of three and a half years was carried out in a UK psychiatric hospital. A total of 112 errors and "near misses" were studied. The reporting rate increased over time. Psychotropic, intramuscular, and as-needed medications were overrepresented in the error reports. Fifteen percent of the errors had the potential to cause moderate or severe harm to patients. The two most common factors cited by nurses as contributing to error causation were a busy, noisy environment and personal factors, such as feeling tired or unsupported. Physicians were cited as having contributed to some errors.  相似文献   
103.
Choroid plexus carcinoma (CPC) is an uncommon central nervous system tumor requiring complete surgical excision for favorable outcome. The authors report the successful treatment of a 2-year-old patient with widely disseminated CPC and Li-Fraumeni syndrome. Following a partial resection of the tumor the patient received chemotherapy consisting of cyclophosphamide, etoposide, and carboplatin. There were no additional surgical procedures and radiation was not administered. Remarkably, the patient remains without evidence of active disease more than 3 years from the completion of therapy. Additional studies are necessary to determine whether this treatment plan can be beneficial to other patients with CPC and whether the patient's p53 mutation had an effect on outcome.  相似文献   
104.
There is a lack of evidence on the prevalence of smoking among mental health nurses, and the beliefs and attitudes they hold about smoking at work. This paper describes results from a cross-sectional survey of clinical staff working in a UK specialist charitable-status psychiatric hospital and focuses on the responses of registered mental health nurses. Questionnaires specifically developed for this study were sent to all 1371 clinical employees. Completed questionnaires were returned by 167 of 429 (38.9%) registered nurses (RNs), 300 of 842 (35.6%) nursing assistants (NAs), and 123 of 200 (61.5%) other health professionals (OHPs). Twenty-nine (17.4%) RNs, 93 (31%) NAs and eight (6.5%) OHPs reported themselves as current smokers. Differences in response to attitudinal questions between groups could not be attributed to age. RN smokers were significantly more likely than RN non-smokers to state that staff should be allowed to smoke with patients, and to report therapeutic value for patients in this activity. RN smokers were less likely than RN non-smokers to report that patients should be encouraged to stop smoking. RNs were significantly more likely than OHPs to report therapeutic value for patients in smoking with staff, even after controlling for the possible confounding effect of smoking status. Implications of the survey are discussed in the context of the international literature, including the disproportionately high smoking prevalence among patients living in psychiatric institutions and current guidelines to move towards no 'smoking allowed' areas for staff working in them.  相似文献   
105.
Three methods for estimation of the equilibrium tissue-to-plasma partition ratios (Kp values) in the presence of tissue concentration time data have been investigated. These are the area method, the open loop (tissue specific) method and the whole body model(closed loop) method, each with different model assumptions. Additionally, multiple imputations, a technique for dealing with deficiencies in data sets (i.e., missing tissues) is used. The estimated Kp values by the three methods have been compared and the limitations and advantages of each approach drawn. The area method, which is essentially model free, gives only a crude estimate of Kp without making any statement of its uncertainty; whereas both the open and closed loop methods provide an estimate of this. The closed loop method, where the most assumptions are made, is the approach that gives the best overall estimates of Kp, which was confirmed by comparing the predicted concentration-time profiles with experimental data. Although the estimates from the closed loop method, as well as the other two methods, are conditioned on the data, they are the most reliable for both propagating parameter variability and uncertainty through a whole body physiologically based model, as well as for extrapolation to human. A series of benzodiazepines, namely alprazolam, chlordiazepoxide, clobazam, diazepam, flunitrazepam, midazolam and triazolam in rat is used as a case study in the current investigation.  相似文献   
106.
In two studies, we examined women's anger expression and its instrumental function in relationships by addressing the following questions: What is the relationship between women's self-reports of instrumentality and their perceived styles of anger expression? In what ways and situations do women see their anger expression as instrumental or goal enhancing? In Study I, we expected that women's perceived styles of anger expression would be positively related to instrumentality, as measured with the Personal Attributes Questionnaire (PAQ; Spence, Helmreich, & Stapp, JSAS Catalog of Selected Documents in Psychology, 4, 43, 1974). Although our hypothesis was not supported, a positive relationship did emerge between assertiveness and instrumentality, as predicted. In Study II, we conducted three focus group discussions to elucidate women's experiences of anger and to provide clarification for the results of Study I. We identified group themes related to when women experienced their anger expression as instrumental as well as when women perceived themselves as noninstrumental in anger-arousing situations. In their narratives, women explained how they make decisions about expressing their anger based on relationship concerns.  相似文献   
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109.
Following observations that curcumin inhibited proliferation (IC(50)=1-5 microM), invasiveness and progression through S/G2/M phases of the cell cycle in the non-tumourigenic HBL100 and tumourigenic MDA-MB-468 human breast cell lines, it was noted that apoptosis was much more pronounced in the tumour line. Therefore, the ability of curcumin to modulate signalling pathways which might contribute to cell survival was investigated. After pre-treatment of cells for 20 min, curcumin (40 microM) inhibited EGF-stimulated phosphorylation of the EGFR in MDA-MB-468 cells and phosphorylation of extracellular signal regulated kinases (ERKs) 1 and 2, as well as ERK activity and levels of nuclear c-fos in both cell lines. At a lower dose (10 microM), it also inhibited the ability of anisomycin to activate JNK, resulting in decreased c-jun phosphorylation, although it did not inhibit JNK activity directly. In contrast, the activation of p38 mitogen activated protein kinase (MAPK) by anisomycin was not inhibited. Curcumin inhibited basal phosphorylation of Akt/protein kinase B (PKB) in both cell lines, but more consistently and to a greater extent in the MDA-MB-468 cells. The MAPK kinase (MKK) inhibitor U0126 (10 microM), while preventing ERK phosphorylation in MDA-MB-468 cells, did not induce apoptosis. The PI3K inhibitor LY294002 (50 microM) inhibited PKB phosphorylation in both cells lines, but only induced apoptosis in the MDA-MB-468 line. These results suggest that while curcumin has several different molecular targets within the MAPK and PI3K/PKB signalling pathways that could contribute to inhibition of proliferation and induction of apoptosis, inhibition of basal activity of Akt/PKB, but not ERK, may facilitate apoptosis in the tumour cell line.  相似文献   
110.
Polymerizable cyclodextrin derivatives (PCDs) have been proposed as candidates for use in dental therapeutics (Bowen, 1996; Bowen and Reed, 1997). Here, PCD "libraries" were synthesized by quasi-random reactions of 6 moles of methacrylic anhydride plus 6 moles of cyclic glutaric anhydride per mole of beta-cyclodextrin (BCD) in solution. BCD has 21 reactive sites on each of its molecules. These proportions were based on probability calculations, which predicted that the products should have a minimum of 2 polymerizable substituents and acidic ligand groups on practically every one of the diverse product molecules. Matrix-assisted laser desorption/ionization (MALDI) time of flight (TOF) mass spectrometry (MS) gave valuable information regarding the masses of molecular ions representing the molecules that made up the PCD libraries. For the MALDI-TOF MS analyses, small samples were analyzed by the successive application of 3 solutions to the sample holder: the matrix in acetone, the products in water, and sodium trifluoroacetate in water. The resulting spectra had > 40 envelopes of mass peaks above background. The ionic-abundance peak heights had quasi-Gaussian configurations, with central peaks having masses in the neighborhood of 2000 g/mol (Daltons). Regardless of structural permutations within each peak, the range of these peaks was between about 1500 g/mol and 2900 g/mol. This range of masses was in accord with, but perhaps somewhat more narrow than, that predicted by the statistical method, which was based on equal reactivity of all hydroxyl groups. Analysis by MALDI-TOF MS gave valuable data regarding the masses, structures, and characteristics of the products formed and provided unanticipated information to facilitate improvements in future PCD syntheses.  相似文献   
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