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41.
In heat-treated polyamide 6 and polyamide 6,6 fibres UV/VIS-active chromophores are found, which originate from two different sources: one type of chromophore (structured UV spectrum) arises during polycondensation and the spinning of the fibres (molten phase), the other (nonstructured UV spectrum) occurs as a result of a thermo-oxidation is based on conjugated oligoenimies , as is shown by a combination of UV/VIS spectroscopy and fluorescence excitation and emission spectroscopy with chemical analysis. The concentration of the various oligoenimine species depends upon the temperature and duration of the thermooxidation. For a temperature of 160°C and a duration of 2 hours, for example, the following oligoenimine concentrations were found (UV spectroscopy with computer-aided evaluation): for i = 0: 44; i = 1: 13; i = 2: 4; i = 3: 1; i = 4: 0,3 (values expressed in mmol/kg).  相似文献   
42.
The authors in their case report show a case of induced hallucinatory psychosis induced in a wife of a patient with alcoholic hallucinosis. They deal with the nosological position of "folie a deux hallucinatoire" (induced hallucinatory psychosis) and integrate the consequences of the case to the general psychopathological theory of hallucinations.  相似文献   
43.
Temporary electrical stimulation using anal or vaginal electrodes and an external pulse generator has been a treatment modality for urinary urge incontinence for nearly three decades. In 1981 Tanagho and Schmidt introduced chronic electrical stimulation of the sacral spinal nerves using a permanently implanted sacral foramen electrode and a battery powered pulse generator for treatment of different kinds of lower urinary tract dysfunction, refractory to conservative treatment. At our department chronic unilateral electrical stimulation of the S3 sacral spinal nerve has been used for treatment of vesi-courethral dysfunction in 43 patients with a mean postoperative follow up of 43,6 months. Lasting symptomatic improvement by more than 50 % could be achieved in 13 of 18 patients with motor urge incontinence (72,2 %) and in 18 of the 21 patients with urinary retention (85,7 %). Implants offer a sustained therapeutic effect to treatment responders, which is not achieved by temporary neuromodulation. Chronic neuromodulation should be predominantly considered in patients with urinary retention. Furthermore in patients with motor urge incontinence, refusing temporary techniques or in those requiring too much effort to achieve a sustained clinical effect. Despite high initial costs chronic sacral neuromodulation is an economically reasonable treatment option in the long run, when comparing it to the more invasive remaining therapeutic alternatives.  相似文献   
44.
45.
In order to help improve the effectiveness of birth control education programs, a film "It Couldn't Happen to Me" was produced focusing on the psychological motives involved in the non-use of birth control among teenagers. Preliminary evaluation of the film took place with five sample groups: high school students, university students, nursing students, health educators, and Planned Parenthood workers. Survey results indicate that the film is relevant for each of these groups. Pre and posttest measures of the attitudes of the university and nursing samples indicate that the film makes viewers more aware of the psychological factors involved in the non-use of birth control.  相似文献   
46.
Summary Chromatographic analysis of 3,5-cyclic nucleotide phosphodiesterase (PDE) isoenzymes in the cytosol of human neutrophils shows the predominant presence of PDE IV (cAMP specific) and PDE V (cGMP specific). PDE IV is characterized by (1) cAMP selectivity, (2) a KM for cAMP of 1.2 M and (3) a typical rank order of IC 50-values for PDE inhibitors: 0.13, 0.17, 47 and 9.5 M for PDE IV selective rolipram, PDE III/IV selective zardaverine, PDE III selective motapizone and unselective 3-isobutyl-l-methylxanthine (IBMX), respectively. Functions of polymorphonuclear leukocytes (PMN) such as N-formylmethionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide release and fMLP/thimerosal elicited leukotriene (LT) biosynthesis are inhibited by these PDE inhibitors with the same rank order and even lower IC50-values. Measurements of changes in cytosolic Cai in Fura-2 loaded PMN demonstrate a transient Cai increase after stimulation with 0.1 M fMLP and an additional sustained elevation of Cai levels in the presence of thimerosal. PDE inhibitors suppress this sustained phase of Cai release with the same rank order of IC50-values as LT biosynthesis. The correlation between fMLP/thimerosal-induced LT biosynthesis and Cai levels reveal a Cai threshold of 150 nM for arachidonic acid metabolism. cAMP levels in PMN were elevated by PDE inhibitors alone by less than 2-fold. In the presence of fMLP however, cAMP was increased up to 10-fold and the efficacy of PDE inhibitors to increase cAMP paralleled their potency to inhibit PDE IV. It is concluded that (1) suppression of PMN functions is achieved by PDE IV inhibition, (2) necessary cAMP elevations are within 50% increase, (3) superoxide release was affected by cAMP/protein kinase A (PKA) directly whereas (4) for inhibition of LT biosynthesis a cAMP related reduction of Ca-influx is involved. Send offprint requests to Ch. Schudt at the above address  相似文献   
47.
Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches, to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (P450) probe substrates, inhibitors and inducers and for the development of classification systems to improve the communication of risk to health care providers and to patients. While existing guidances cover mainly P450-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently, and should also be addressed. This article was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers.  相似文献   
48.
PURPOSE: A Phase I/IIb multicenter study was conducted to evaluate the safety and immunogenicity of the anti-idiotypic antibody vaccine ACA125 that functionally imitates the tumor antigen CA125 in 119 patients with advanced ovarian carcinoma. A preliminary report on the initial 42 patients demonstrated safety and immunogenicity. EXPERIMENTAL DESIGN: Using the complete intention-to-treat population (n = 119) who received a mean of 9.7 ACA125 applications, survival was analyzed with respect to immunological responses. RESULTS: In 81 patients (68.1%), a specific anti-anti-idiotypic antibody (Ab3) response could be induced. Additionally, the development of CA125-specific antibodies (Ab1') and antibody-dependent cell-mediated cytotoxicity of CA125-positive tumor cells was observed in 50.4% and 26.9% of patients, respectively. The median survival of all patients was 19.4 months (range, 0.5-56.1 months). Ab3-positive patients showed a significantly longer survival (median, 23.4 months; P < 0.0001) as compared with Ab3-negative patients (median, 4.9 months). A positive Ab3 response remained associated with longer survival when controlling for other prognostic factors including FIGO (International Federation of Gynecologists and Obstetricians) stage, response to and type of first-line chemotherapy, number of previous treatments, or concomitant antitumor therapy. With regard to safety, repeated vaccination was well tolerated. No serious adverse events related to the application of ACA125 occurred. CONCLUSIONS: Although the uncontrolled design of this study prevents definitive conclusions with respect to subgroups, the data support a relationship between Ab3 response and survival time. Thus, the need for further randomized, controlled clinical trials to establish efficacy of the vaccine ACA125 seems to be indicated.  相似文献   
49.
BACKGROUND AND PURPOSE: The appropriate application of 3-D CRT and IMRT for HNSCC requires a standardization of the procedures for the delineation of the target volumes. Over the past few years, two proposals--the so-called Brussels guidelines from Grégoire et al., and the so-called Rotterdam guidelines from Nowak et al.--emerged from the literature for the delineation of the neck node levels. Detailed examination of these proposals however revealed some important discrepancies. MATERIALS AND METHODS: Within this framework, the Brussels and Rotterdam groups decided to review their guidelines and derive a common set of recommendations for delineation of neck node levels. This proposal was then discussed with representatives of major cooperative groups in Europe (DAHANCA, EORTC, GORTEC) and in North America (NCIC, RTOG), which, after some additional refinements, have endorsed them. The objective of the present article is to present the consensus guidelines for the delineation of the node levels in the node-negative neck. RESULTS AND CONCLUSIONS: First a short discussion of the discrepancies between the previous Brussels and the Rotterdam guidelines is presented. The general philosophy of the consensus guidelines and the methodology used to resolve the various discrepancies are then described. The consensus proposal is then presented and representative CTVs that are consistent with these guidelines are illustrated on CT sections. Last, the limitations of the consensus guidelines are discussed and some concerns about the direct applications of these guidelines to the node-positive neck and the post-operative neck are described.  相似文献   
50.
Dietary-induced changes in tissue levels of polyunsaturated fatty acids modify inflammatory reactions through changes in the synthesis of lipid and peptide mediators of inflammation. Four semipurified 20% fat diets, based on beef tallow (BT), safflower oil (SFO), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were provided. The DHA and EPA ratios of the (n-3) fatty acid-based diets were 1.1 and 3.4, respectively. The effect of prefeeding diets differing in EPA to DHA ratios prior to the induction of streptococcal cell wall (SCW) arthritis in female Lew/SSN rats was examined. Weanling rats were fed diets for 5 wk before arthritis induction and 5 wk post-arthritis induction. Footpad thickness, hock circumference, plasma and macrophage fatty acids and histological assessment were compared. There were no differences in food intake and final body weights among the groups. Footpad inflammation, reported as percentage change (adjusted for growth) was greatest for rats fed the BT-based diet, intermediate in those fed the SFO-based diet and least for the rats fed the EPA- and DHA-based diets (P < 0.05). Macrophage phospholipids revealed cellular incorporation of EPA and DHA from the fish-oil based diets which modified lipid and peptide mediators of inflammation. Histological sections of rat hocks ranked by severity of arthritis-related changes suggested that the SFO- and EPA-based diets were more successful in ameliorating the destructive arthritic phase in hock joints than the BT- and DHA-based diets (P = 0.09) in this model of arthritis. The course of SCW-induced arthritis can be altered by diet-induced changes in macrophage fatty acid composition. The EPA-based diet is more effective in suppression of inflammation than the DHA-based diet.  相似文献   
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