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91.
Siconolfi Daniel Storholm Erik D. Vincent Wilson Pollack Lance Rebchook Gregory M. Huebner David M. Peterson John L. Kegeles Susan M. 《Archives of sexual behavior》2021,50(8):3621-3636
Archives of Sexual Behavior - Men who have sex with men (MSM) experience high prevalence of sexual violence (SV), and SV has well-documented effects on health. Research gaps are especially evident... 相似文献
92.
Jessen Reidar Schei Wæhre Anne David Linda Stänicke Erik 《Archives of sexual behavior》2021,50(8):3489-3503
Archives of Sexual Behavior - A growing number of adolescents are seeking medical care to alleviate gender dysphoria (GD). This qualitative study explored the subjective experiences of GD among... 相似文献
93.
94.
Annaert Pieter Kinget Renaat Naesens Lieve de Clercq Erik Augustijns Patrick 《Pharmaceutical research》1997,14(4):492-496
Purpose. To evaluate intestinal transport, uptake and metabolism characteristics of the bis(pivaloyloxymethyl)-ester [bis(POM)-ester] of the antiviral agent 9-(2-phosphonylmethoxyethyl)adenine [PMEA].
Methods. Intestinal transport, uptake and metabolism of bis(POM)-PMEA were studied using an in vitro cell culture system of the intestinal mucosa (Caco-2 monolayers). Concentrations of bis(POM)-PMEA and its metabolites mono(POM)-PMEA and PMEA were determined using a reversed-phase HPLC method. Enzymatic stability of bis(POM)-PMEA was evaluated by incubation with purified liver carboxylesterase, homogenates of Caco-2 cells and scraped pig small intestinal mucosa.
Results. The use of bis(POM)-PMEA as a prodrug of PMEA resulted in a significant increase in transport of total PMEA [bis(POM)-PMEA, mono(POM)-PMEA and PMEA] across Caco-2 monolayers. While transepithelial transport of PMEA (500 M) was lower than 0.1% during a 3 hr incubation period, transport of total PMEA after addition of bis(POM)-PMEA (100 M) amounted to 8.8% over the same incubation period. Only 23% of the amount transported appeared as intact bis-ester at the basolateral side, while 33% of this amount was free PMEA and 44% was mono(POM)-PMEA, suggesting susceptibility of the prodrug to chemical and enzymatic degradation. Uptake studies revealed that only negligible amounts of bis(POM)-PMEA (< 0.2%) were present inside the cells. Very high intracellular concentrations of PMEA were found 1.2 mM, after a 3 hr incubation with 50 M bis(POM)-PMEA), which suggests that PMEA was trapped inside the cells probably due to its negative charge. This explains that efflux of PMEA was relatively slow (25% of the intracellular amount in 3 hr). Enzymatic degradation of the prodrug by carboxylesterase was confirmed by incubation of bis(POM)-PMEA with purified enzyme (Km = 87 M and Vmax = 9.5 M/min). Incubation of bis(POM)-PMEA (10 M) with cell homogenate of Caco-2 monolayers and pig small intestinal mucosa produced similar degradation profiles.
Conclusions. The use of the bis(POM)-prodrug significantly enhances the intestinal permeability of PMEA. Intracellular trapping of PMEA in the intestinal mucosa may result in slow release of PMEA to the circulation after oral administration of bis(POM)-PMEA. 相似文献
95.
Comparison of non-invasive approaches to red marrow dosimetry for radiolabelled monoclonal antibodies 总被引:1,自引:0,他引:1
Marian A. B. D. Plaizier Jan C. Roos Gerrit J. J. Teule Erik B. van Dieren Wim den Hollander Hidde J. Haisma Robert L. DeJager Arthur van Lingen 《European journal of nuclear medicine and molecular imaging》1994,21(3):216-222
Red marrow is usually the dose-limiting organ during radioimmunotherapy. Several non-invasive approaches to calculate the red marrow dose have been proposed. We compared four approaches to analyse the differences in calculated red marrow doses. The data were obtained from immunoscintigraphy of two antibodies with different red marrow kinetics [iodine-131-16.88 IgM and indium- 111-OV-TL-3 F(ab)2]. The approaches are based on, respectively, homogeneously distributed activity in the body, a red marrow-blood activity concentration ratio of 0.3, scintigraphic quantification, and a combination of the second and third approaches. This fourth approach may be more adequate because of its independence from the chosen antibody. In addition, the influence of activity accumulation in liver, kidneys or cancellous bone on red marrow dose was studied. The calculated red marrow dose varied between 0.14 and 0.42 mGy/MBq for 111 In-OV TL-3 and between 0.13 and 0.68 mGy/MBq for 131I-16-88. If the radiopharmaceutical shows high affinity for cancellous bone or another organ situated near the red marrow, the activity in these organs must be included in dose calculations. This study shows a large variation in calculated red marrow dose and selection of the definitive non-invasive approach awaits validation.
Correspondence to: M.A.B.D. Plaizier 相似文献
96.
This paper presents a 7-12 year (mean 9.8 years) follow-up of 92 extremely obese patients treated with Marlextrade mark mesh gastric banding (GB). The follow-up rate was 92% (85 patients). Weight loss was initially good (an average reduction in BMI of 13 during the first year), but late weight gain has been a common complaint and a reason for reoperation. Other complications that necessitated reoperation were severe vomiting and esophagus not amenable to medical treatment. Four patients have developed signs of Barrett's esophagus at late follow-up. Forty-six patients (50%) were reoperated 70 times for correction of the band or conversion to vertical banded gastroplasty (VBG). The most common reoperative procedure was conversion to VBG (38 patients). Only 25 (31%) of the 80 patients with long-term follow-up have an intact band. Our results show the need of long follow-up and that this GB cannot be recommended for the treatment of morbid obesity. 相似文献
97.
The effects of caffeine on cytoplasmic Ca2+ oscillations induced by carbachol and guanosine 5-O-(3-thiotriphosphate) (GTP--S) were studied in individual mouse pancreatic ß-cells clamped at a hyperpolarized potential. Addition of 10 mM caffeine did not affect the cytoplasmic Ca2+ concentration ([Ca2+]1) in ß-cells exposed to 20 mM glucose and hyperpolarized with diazoxide. Under similar conditions 100 M carbachol induced a typical response with a marked [Ca2+]i peak followed by a lower sustained elevation. Irrespective of whether 10 mM caffeine was present, there were [Ca2+]i transients with frequencies of 1–5/min superimposed on the sustained phase in 50–60% of the cells. In previously non-exposed cells the introduction of 10 mM caffeine caused temporary lowering of the sustained phase with disappearance of the transients. Subsequent omission of caffeine in the continued presence of carbachol caused a marked [Ca2+]i peak followed by reappearance of the [Ca2+]i, transients. However, in cells oscillating in the presence of caffeine its omission caused disappearance of the transients. In this case reintroduction of caffeine restored the transients.In cells kept at –70 mV by a patch pipette containing 100 M GTP--S and 3 mM Mg-ATP there were [Ca2+]i transients with frequencies of 0.5–2.5/min. These transients were sufficiently pronounced to activate repetitively a K+ current. Addition of 10 mM caffeine caused disappearance of the [Ca2+]i transients or reduction of their amplitudes and frequencies.The results indicate that caffeine does not activate Ca2+-induced Ca2+ release in hyperpolarized ß-cells but inhibits the Ca2+-mobilizing effect of inositol 1,4,5-trisphosphate.
Correspondence to: E. Gylfe at the above address 相似文献
98.
Bernd Mühlbauer Erik Hartenburg Hartmut Osswald 《Naunyn-Schmiedeberg's archives of pharmacology》1994,349(3):244-249
Previously, we have found that feeding is a dominant factor controlling urinary dopamine excretion (UDA) in conscious rats (Mühlbauer and Osswald 1992). Since the renal response to feeding is also characterized by an increase in glomerular filtration rate (GFR), we wanted to investigate in a first step whether the feeding-induced elevations of GFR and UDA could be causally related phenomena. Therefore, we studied the influence of dopamine synthesis and dopamine receptor blockade on the renal response to amino acid infusion (AA) in thiopental anesthetized rats. AA infusion (n = 7) increased GFR by 33±7% (P<0.001) and UDA by 87±19% (P<0.001). In the presence of benserazide (BZD, n = 5), an inhibitor of dopamine synthesis, infused i.v. at a dose of 30 g/min/kg, UDA was suppressed to values below detection limit and the AA-induced GFR increase was abolished. Continuous intravenous infusion of the DA1 receptor antagonist SCH 23390 (SCH, n = 7) in a dose of 4.0 g/kg/min did not prevent the AA-induced increase in GFR (33±3%, P<0.001) and UDA (97±12%, P< 0.001). In contrast, S-sulpiride (SUL), a specific DA2 receptor antagonist, infused continuously i.v. in a dose of 5 g/kg/min, completely abolished the AA-induced GFR increase, while UDA was increased 1.6-fold (P<0.01). Like BZD, both dopamine receptor antagonists did not affect renal sodium excretion substantially.Our results suggest, that endogenous dopamine could act as a mediator in the renal response to amino acid infusion in the rat, most likely by activation of DA2 receptors.
Correspondence to:B. Mühlbauer at the above address 相似文献
99.
100.
Erik Nord 《Health care analysis》1999,7(2):167-175
By describing societal value judgements in health care in numerical terms one may in theory increase the precision of guidelines
for priority setting and allow decision makers to judge more accurately the degree to which different health care programs
provide societal value for money. However, valuing health programs in terms of QALYs disregards salient societal concerns
for fairness in resource allocation. A different kind of numerical valuation of medical interventions, that incorporates concerns
for fairness, is described. The usefulness to decision makers of such numerical information remains to be tested.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献