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41.

Introduction

Contraceptives improve women's lives and public health, but many women discontinue their contraceptive method owing to dissatisfaction. An underexamined aspect of contraceptive discontinuation is sexual acceptability, or how contraception affects sexual experiences. Investigators' aims were two-fold: 1) to document changes in multiple domains of women's sexual experiences with their intrauterine device (IUD) or contraceptive implant over time and 2) to examine whether these sexuality factors were associated with method continuation at 12 months.

Methods

We enrolled 200 eligible family planning clients and collected data at baseline and at 1, 3, 6, and 12 months. Sexual acceptability measures included the Female Sexual Function Index-6, the New Sexual Satisfaction Scale, and participants’ perceptions of whether their contraceptive method had had a neutral, positive, or negative effect on their sex life. Survival analysis and Cox regression with time-varying covariates related sexuality measures to method continuation over time while controlling for other relevant factors.

Results

Among 193 women who received an IUD or implant, 20% selected the copper IUD, 46% the levonorgestrel IUD, and 34% the etonogestrel implant. Ten percent discontinued their method during the year. Although changes in Female Sexual Function Index-6 and New Sexual Satisfaction Scale scores were not associated with discontinuation, individuals who perceived that their method detracted from their sexual experience had significantly higher removal rates than those who reported no sexual changes or positive sexual changes (adjusted hazard ratio, 8.04; 95% CI, 1.53–42.24), even when controlling for method type, bleeding changes, and a variety of covariates and controls.

Conclusions

Although limited by the small sample of discontinuers, we found that women's perceptions of how their method affects their sex life were associated with contraceptive continuation over time. Sexual acceptability should receive more attention in both contraceptive research and counseling.  相似文献   
42.
小剂量MK—801加强100Hz电针抑制大鼠吗啡戒断症状的作用   总被引:1,自引:0,他引:1  
目的 :观察小剂量MK 80 1(dizocilpine)是否能加强 10 0Hz电针 (electroacupuncture ,EA)抑制大鼠吗啡戒断症状的作用。方法 :大鼠皮下注射递增剂量的吗啡 5天 (每天 3次 ) ,使其对吗啡形成依赖 ,最后一次注射吗啡后 1h ,分别腹腔 (i.p .,0 .0 3mg/kg)或蛛网膜下腔 (i.t.,10 0ng/ 10 μl)注射MK 80 1,注射后 15min给予 10 0HzEA。MK 80 1注射和 10 0HzEA共进行 3次 ,两次之间相隔5h。最后一次EA结束后 30mini.p .纳洛酮 (1mg/kg)催促戒断症状 ,并观察记录 5种戒断症状的表现。结果 :(1)单纯i.p .MK 80 1仅能显著降低直立症状 ;单纯 10 0HzEA能够显著降低直立和振翼样抖动 ;i.p .MK 80 1联合 10 0HzEA能显著降低跳跃、直立、振翼样抖动和体重丢失等 4种戒断症状。 (2 )单纯i.t.MK 80 1能显著降低振翼样抖动 ;i.t .MK 80 1联合EA能显著降低上述四种戒断症状。结论 :小剂量的MK 80 1可加强 10 0HzEA抑制戒断症状的作用 ;联合使用的效果优于单纯应用EA或MK 80 1。  相似文献   
43.
Schizophrenia is considered as a “neurodegenerative” and “neurodevelopmental” disorder, the pathophysiology of which may include hypofunction of the N‐methyl‐d ‐aspartate receptor (NMDA‐R) or subsequent pathways. Accordingly, administration of NMDA‐R antagonists to rodents during the perinatal period may emulate some core pathophysiological aspects of schizophrenia. The effect of 4‐day (postnatal day; PD 7–10) administration of MK‐801, a selective NMDA‐R antagonist, on gene expression in the medial prefrontal cortex (mPFC), hippocampus, and amygdala was evaluated using quantitative polymerase chain reaction methods. Specifically, we sought to determine whether genes related to Glu transmissions, for example those encoding for NMDA‐Rs, metabotropic Glu receptors (mGluRs), or Glu transporters, were altered by neonatal treatment with MK‐801. Model rats showed downregulation of the mGluR3 subtype in the mPFC around puberty, especially at PD 35 in response to MK‐801 or during ontogenesis without pharmacological manipulations. Genes encoding for other mGluRs subtypes, that is NMDA‐Rs and Glu transporters, were not affected by the neonatal insult. These results suggest that NMDA‐R antagonism in the early course of development modulates the expression of mGluR3 in mPFC around puberty. Thus, mGluR3 may serve as a potential target to prevent the onset and progression of schizophrenia. Synapse 68:202–208, 2014 . © 2014 Wiley Periodicals, Inc.  相似文献   
44.
45.
ABSTRACT

Introduction: Since its introduction in clinical practice one century ago for the treatment of respiratory allergic diseases, allergen-specific immunotherapy (AIT) has exhibited a relevant clinical efficacy that was subsequently confirmed in controlled trials. Thus, AIT has been accepted worldwide, as testified by guidelines and international documents. AIT is considered pivotal in the management of allergic rhinitis with or without conjunctivitis and with or without asthma. These conditions, in addition to hymenoptera venom allergy, currently are the accepted indications. The use of AIT in house-dust mite allergy still remains debated, especially due to the methodological problems in assessing this form of respiratory allergy. The more recent experimental data on MK-8237 sublingual tablets provided evidence that AIT, in the sublingual form, is effective in dust mite allergy.

Areas covered: At present, the evidence of the efficacy of AIT in conditions other than respiratory allergy are not conclusive, but encouraging results have been obtained in food allergy and atopic dermatitis. Herein, the authors discuss the data for these indications.

Expert opinion: Not all patients respond to AIT in the same way. Accordingly, AIT represents a promising path to precision medicine and hopefully will be able to reduce this burden of non-responding patients.  相似文献   
46.
Nociceptin/Orphanin FQ (N/OFQ) is a 17 amino acid peptide that was deorphanized in 1995. The generation of specific agonists, antagonists and receptor deficient mice and rats has enabled progress in elucidating the biological functions of N/OFQ. Additionally, radio-imaging technologies have been advanced for investigation of this system in animals and humans. Together with traditional neurobehavioral techniques, these tools have been utilized to identify the biological significance of the N/OFQ system and its interacting partners. The present review focuses on the role of N/OFQ in the regulation of feeding, body weight homeostasis, stress, the stress-related psychiatric disorders of depression and anxiety, and in drug and alcohol dependence. Critical evaluation of the current scientific preclinical literature suggests that small molecule modulators of nociceptin opioid peptide receptors (NOP) might be useful in the treatment of diseases related to these biological functions. In particular, the literature data suggest that antagonism of NOP receptors will produce anti-obesity and antidepressant activities in humans. However, there are also contradictory data discussed. The current literature on the role of N/OFQ in anxiety and addiction, on the other hand points primarily to a role of agonist modulation being potentially therapeutic. Some drug-like molecules that function either as agonists or antagonists of NOP receptors have been optimized for human clinical study to test some of these hypotheses. The discovery of PET ligands for NOP receptors, combined with the pharmacological tools and burgeoning preclinical data set discussed here bodes well for a rapid advancement of clinical understanding and potential therapeutic benefit.  相似文献   
47.
《Neurological research》2013,35(5):430-438
Abstract

Objective: The aim of this study was to investigate whether NMDA receptor was involved in the upregulation of multidrug resistance protein 2 (Mrp2) expression during status epilepticus (SE).

Methods: The alterations in the expression of Mrp2 at various time points after SE, and the inhibition of glutamate N-methyl-D-aspartate (NMDA) receptor on Mrp2 expression in hippocampus were both tested by quantitative real-time polymerase chain reaction and western blot. Moreover, immunofluorescence was also used to analyze the impact of the NMDA receptor antagonist, MK-801, on the distribution of Mrp2 in different brain areas.

Results: The results showed that gene encoding Mrp2 was upregulated in hippocampus at 6 hours after the end of SE, and this initial increase was followed by gradual normalization. While between 3 and 72 hours after the end of SE, the protein level of Mrp2 was upregulated in hippocampus, with the highest level emerging at 24 hours. The increment of Mrp2 gene and protein induced by SE was prevented by MK-801 at 6 and 24 hours respectively after the end of SE in the hippocampus. Moreover, immunofluorescence showed that seizures-induced increase of Mrp2 expression was attenuated by the administration of MK-801 mainly in capillaries. Rats after SE exhibited a significant upregulation of Mrp2 in the capillary endothelial cells of the cerebral cortex, piriform cortex, and hippocampus, compared with those in control at 24 hours after the end of SE.

Conclusion: The results indicated that the NMDA receptor plays an important role in the upregulation of Mrp2 expression in the blood–brain barrier.  相似文献   
48.
Background MK-1, the target molecule of FU-MK-1, is encoded by the GA733-2 gene, which is currently being used as a target in clinical trials for gastric, intestinal and biliary cancer treatment with monoclonal antibodies. Also of interest is p53, a protein that has been intensively investigated in relation to particular types of tumors, patterns of metastases, tumor stage, and prognosis. Methods The expression of p53 protein and MK-1 antigen was investigated in specimens from 42 patients with gastric carcinoma. The specimens were stained by the avidin-biotin peroxidase technique for immunohistochemical examination. Results MK-1 was positive in 21 (50%) of the 42 cases. MK-1 expression was more frequent in cardia tumors (71%), in large (>3 cm) tumors (60%–64%), and in specimens from patients with more than five metastatic lymph nodes (69%). p53 expression was present in 20 (48%) of the 42 cases. Of these 20 patients, 15 (52%) had tubular adenocarcinoma (TA) and 5 (38%) had signet ring cell carcinoma. p53 expression was more frequent in the tumors of male patients (55% vs 27%); in poorly differentiated TAs (60% vs 47% in well-to-moderately differentiated TAs); in smaller tumors (£3 cm, 72% vs 43%–50% in larger tumors); in patients with a prominent inflammatory response (61% vs 21%; P < 0.02); and in patients with lymphatic vessel invasion (77% vs 34%; P < 0.02). However, p53 expression was less frequent in the presence of more than five metastatic lymph nodes (23% vs 60% for five or fewer nodes; P < 0.05). Most patients with p53- and MK-1-positive gastric carcinomas and those more than five metastatic lymph nodes had a poor prognosis. Conclusion The study found that the expression of both p53 and MK-1 was frequent in aggressive gastric carcinomas; however, extensive lymph node involvement (more than five nodes) was the only significant factor related to overall survival.  相似文献   
49.
BACKGROUND: Short-sleep (SS) mice exhibit higher locomotor activity than do long-sleep (LS) mice when injected with low doses of ethanol or the noncompetitive N-methyl-D-aspartate receptor (NMDAR) antagonist MK-801 (dizocilpine). SS mice also have higher densities of brain NMDARs. However, two strains of LS X SS recombinant inbred (RI) mice also show differential activation to ethanol and MK-801, but have similar numbers of NMDARs. Here we used inbred LS (ILS) and SS (ISS) mice to investigate further the relationship between NMDARs and sensitivity to the stimulant effects of low doses of ethanol. METHODS: Open field activity and spontaneous alternations were measured after saline or drug injection. [3H]MK-801 binding parameters were determined in hippocampus, cortex, striatum, and nucleus accumbens. Extracellular field excitatory postsynaptic potentials (fEPSPs) were recorded in the CA1 region of hippocampal slices. RESULTS: Systemic injection of either ethanol or MK-801 increased locomotor activity to a greater extent in ISS mice than in ILS mice. The competitive NMDAR antagonist 2-carboxypiperazin-4-yl-propyl-1-lphosphonic acid (+/- CPP) depressed activity of ILS, but not ISS, mice. No strain differences were observed in spontaneous alternations or in the number or affinity of NMDARs in the brain regions examined. Likewise, the magnitudes of hippocampal NMDAR-mediated fEPSPs were similar in ILS and ISS mice and were inhibited to the same extent by a competitive NMDAR antagonist. However, both ethanol and the NMDAR NR2B receptor antagonist ifenprodil inhibited the late component of hippocampal NMDAR fEPSPs to a greater extent in ISS, than in ILS, mice. CONCLUSIONS: Differential ethanol- and MK-801-induced behavioral activation in ILS and ISS mice was not associated with differences in NMDAR number. Nonetheless, pharmacological differences in hippocampal NMDAR responsiveness suggest that ISS mice express NMDARs that have a greater sensitivity to noncompetitive, but not competitive, NMDAR antagonists. These differences, which may reflect differences in NMDAR subunit composition, could underlie the differential responsiveness to low doses of ethanol in ILS and ISS mice.  相似文献   
50.
The aim of this study is to pursue roles of N-methyl-d-aspartate (NMDA) receptors in the anteroventral third ventricular region (AV3V; a pivotal area for autonomic functions) in controlling vasopressin (AVP) release and cardiovascular system. In conscious rats, we examined effects of AV3V infusion of MK-801 (a selective antagonist for NMDA receptor) on plasma AVP, osmolality, electrolytes, arterial pressure and heart rate, in the absence or presence of NMDA, hyperosmotic or prostaglandin (PG) E2 stimulus. The AV3V infusion of NMDA caused significant increases in plasma AVP, osmolality and sodium, hematocrit, arterial pressure and heart rate after 5 or 15min. When NMDA was administered into the cerebral ventricle, relatively smaller elevations were observed only in plasma AVP and arterial pressure. The effects of AV3V infusion of NMDA were nearly completely prevented by MK-801 applied to the same region before 15min. The application of MK-801 was also potent to block rises of plasma AVP elicited by AV3V injection of PGE2 or i.v. infusion of hypertonic saline. However, it inhibited neither increases of arterial pressure and heart rate due to the PGE2 treatment nor those of arterial pressure, plasma osmolality and sodium in response to the osmotic load. Histological analysis on the AV3V infusion sites of NMDA, MK-801 and PGE2 indicated that they had been located in the structures such as the median and medial preoptic nuclei, periventricular nucleus and medial preoptic area. These results suggest that stimulation of AV3V NMDA receptors in the basal state may facilitate AVP secretion and cause pressor and tachycardiac actions, and that these receptors may be involved in both the hyperosmolality- and PGE2-induced hormone release, but not in the cardiovascular responses to these stimuli.  相似文献   
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