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581.
582.
Psychiatric disorders in pregnancy   总被引:1,自引:0,他引:1  
This review, although not exhaustive, provides information on the potential impact of psychiatric illness on obstetric outcome. There is clear evidence that psychiatric illness poses a risk to pregnancy outcome. There productive safety data on many of the available treatments fail to demonstrate a clear risk from treatment. The medications with clear teratogenic, neonatal, and developmental risks are, not surprisingly, those used to treat some of the most severe and debilitating psychiatric illnesses. Even the amount of information available is inadequate without some straightforward clinical guidelines. A model of risk for illness and treatments of illnesses during pregnancy developed by the authors' group reminds clinicians that nonexposure does not exist. Rather, the decision is which type of exposure is in the best interest of the patient and family-exposure to illness or exposure to treatment. Regardless of the choice, clinicians are encouraged to think in terms of reducing the total number of exposures; that is, if choosing to treat, patients should be kept well by adjusting and monitoring medications-partial treatment simply provides exposure to illness and treatment. Guidelines to accomplish the goal of minimizing exposures include: 1. Treating women of reproductive capacity from the first visit as if they are pregnant: choosing treatments with reproductive safety information (eg, new and improved = no data) and providing supplemental folic acid for all women (800 microg), with higher doses for those treated with anticonvulsants (3 to 4 mg).2. For women who conceive while taking a medication, and if it was efficacious for them, then the majority of decisions for medication selection should be considered already made for pregnancy and lactation (eg, do not switch medications once pregnant or for breastfeeding, as that simply exposes the baby to a second medication and the data previously discussed do not apply). 3. Because the serum concentration of most medications decreases during pregnancy, establishing criteria a priori for increasing the maternal daily dose; as a general rule, sleep patterns are good markers of psychiatric illnesses. 4. Always preferring monotherapy to two medications. 5. Obtaining up-to-date information at www.emorywomensprogram.org (a website with links to many support groups, reproductive safety registries) or other women's health websites. These basic guidelines can help decrease the number of exposures and aid in conducting clinical care with at least some reproductive safety data.  相似文献   
583.
报告1例苯巴比妥治疗Gilbert综合征致固定性药疹的少见病例,并复习了相关文献.固定性药疹是药物过敏反应中皮肤损害的常见疹型, 但由苯巴比妥所致者较少见.对苯巴比妥过敏的部分患者可有磺胺、去痛片过敏史;某些复方制剂含有苯巴比妥,故使用苯巴比妥前应仔细了解有无磺胺、去痛片过敏史,对复方制剂必须清楚其组成成分,防止苯巴比妥引起不良反应.  相似文献   
584.
Douglas  SW; Adamson  JW 《Blood》1975,45(1):55-65
Marrow regulation and iron metabolism were evaluated in 17 patients with mild or moderate anemia associated with chronic disorders. In addition, whole blood P50 and red cell 2,3-diphosphoglycerate (DPG) levels were measured. The study group consisted of seven patients with non-hematologic malignancies, nine with infection or inflammation, and one with idiopathic hypoproliferative anemia. The mean whole blood P50 and DPG levels were elevated to 28.5 +/- 1.9 mm Hg and 7.03 +/- 0.83 mumole/ml packed RBC, respectively, as compared to normal values of 26.6 +/- 0.6 mm Hg and 4.83 +/- 0.33 mumole/ml packed RBC. Erythropoietin (ESF) excretion was variable (1.1-28.7 IRP U, day), clearly elevated above normal in only three patients and, within the study group, bore no relation to hematocrit. While nine of the 17 subjects had ESF excretion rates within the 95% limits predicted by hematocrit, the remaining eight had lower than expected values. No significant differences in ferrokinetics, ESF excretion, or hematologic profile were found between patients with malignancy and those with inflammation. Marrow transit times correlated inversely with both serum and urine ESF activity (r = -0.57, p less than 0.02; and r = -0.63, p less than 0.01, respectively), indicating that the marrow reticulocyte release response to ESF stimulation was unimpaired. Erythroid iron turnovers were unrelated to serum or urinary ESF activity but were significantly correlated with serum iron levels expressed as microgram/100 ml whole blood (r = 0.56, p less than 0.02). These studies suggest that there is an intraerythrocytic response to the anemia in this group of patients, document that reduced ESF production is not a uniform finding with the anemia of chronic disorders, and provide evidence that the marrow proliferative response to anemia is limited in many patients primarily by the availability of iron.  相似文献   
585.
DICER1 plays a critical role in microRNA (miRNA) biogenesis. Recurrent somatic 'hotspot' mutations at the four metal‐binding sites within the RNase IIIb domain of DICER1 were identified in ovarian sex cord‐stromal tumours and have since been described in other paediatric tumours. In this study, we screened the RNase IIIb domain of DICER1 in 290 endometrial tumours and identified six cases with hotspot mutations, including two cases affected by an atypical G1809R mutation directly adjacent to a metal‐binding site. Using Illumina and Sanger targeted resequencing, we observed and validated biallelic DICER1 mutations in several cases with hotspot mutations. Through in vitro DICER1 cleavage assays, small RNA deep sequencing and real‐time PCR, we demonstrated that mutations adding a positively charged side chain to residue 1809 have similar detrimental effects on 5p miRNA production to mutations at the metal‐binding sites. As expected, 5p miRNAs were globally reduced in tumours and cell lines with hotspot mutations. Pathway analysis of gene expression profiles indicated that genes de‐repressed due to loss of 5p miRNAs are strongly associated with pathways regulating the cell cycle. Using a Dicer1‐null mouse cell line model, we found that expression of DICER1 hotspot mutants promoted cell proliferation, whereas wild‐type (WT) DICER1 inhibited cell proliferation. Furthermore, targets of let‐7 family miRNAs are enriched among the up‐regulated genes, suggesting that loss of let‐7 may be impacting downstream pathways. Our results reveal that DICER1 hotspot mutations are implicated in common malignancies and may constitute a unique oncogenic pathway. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
586.
Three group B Neisseria meningitidis isolates, recovered from meningococcal disease cases in Canada and typed as B:2c:P1.5, were characterized. Multilocus sequence typing showed that all three isolates were related because of an identical sequence type (ST) 573. Isolates typed as 2c:P1.5 are common in serogroup Y meningococci but rare in isolates from serogroups B or C. Although no serogroup Y isolates have been typed as ST-573, eight isolates showed five to six housekeeping gene alleles that were identical to that of ST-573. This suggested that the B:2c:P1.5 isolates may have originated from serogroup Y organisms, possibly by capsule switching.Key Words: Capsule switching, Neisseria meningitidis, Serogroup YNeisseria meningitidis is a significant pathogen that causes invasive meningococcal disease (IMD). The average case fatality rate of 9% to 12% remains high despite the availability of effective antibiotics and vaccines (1). Laboratory study and surveillance of N meningitidis involves the characterization of a number of surface markers of the bacterium, including its capsule and outer membrane proteins (OMPs). Most epidemiological studies of meningococcal disease rely on differentiating meningococcal isolates based on their serogroup, serotype and serosubtype. Serogrouping is determined by the demonstration of serologically distinct epitopes present on chemically and structurally different capsules. Serotyping and serosubtyping rely on the detection of distinct epitopes present on three of five different classes of OMPs of N meningitidis. Serotyping epitopes are found on the class 2 or class 3 OMP (also called PorB) of N meningitidis; these OMPs are expressed in a mutually exclusively manner (ie, a strain will only express either a class 2 or class 3 OMP but not both). Serosubtyping epitopes are present on the class 1 OMP (also called PorA). Based on this nomenclature scheme, a strain can therefore be characterized by its antigenic formula; for example, B:15:P1.7,16 refers to serogroup B, serotype 15 and serosubtype P1.7,16.One of the most important virulence factors of meningococci is the capsular polysaccharide antigen, which is also the basis for serogrouping and is the target antigen for the currently licensed vaccines against A, C, Y and W135 organisms. Of the 13 known serogroups, five (serogroups A, B, C, Y and W135) are responsible for most of the meningococcal disease worldwide (2). In North America, most endemic and epidemic strains belong to serogroups B, C, Y and W135 (3,4). Capsules of serogroups B, C, Y and W135 meningococci contain sialic acid, either as a homopolymer of sialic acids assembled by alpha-2,8 linkages (serogroup B) or alpha-2,9 linkages (serogroup C), or as a heteropolymer of sialic acids with glucose (serogroup Y) or galactose (serogroup W135). Besides demonstrating structural similarities, these four serogroups of meningococci also have very similar capsule polysaccharide synthesis (cps) gene loci (5). Because of this similarity, capsule switching has been demonstrated in vivo and in vitro by specific gene replacement within the cps loci between different serogroups. To date, a number of IMD cases have been described in the literature to be caused by organisms in which capsule switching between serogroup B and C meningococci occurred (6-8).In the present paper, the authors describe three unusual serogroup B meningococci isolated from separate IMD cases in Nanaimo, British Columbia, that presented with the OMP antigens 2c:P1.5, characteristic of serogroup Y strains found in Canada (4). This antigenic profile prompted the authors to examine the relationship of these three serogroup B strains with antigenically similar serogroup Y organisms isolated in Canada. The authors describe the characterization of these antigenically similar isolates and postulate that the B:2c:P1.5 isolates arose by capsule switching from serogroup Y organisms.  相似文献   
587.
We tested the hypotheses that rendering sensory input about hand location imprecise increases a classically conditioned pain expectancy effect, increases generalization of the effect to novel locations and reduces extinction of the effect. Forty healthy volunteers performed movements with their right hand along predefined paths. Each path passed through 2 locations that were defined as either i) the conditioned stimulus (CS+; paired with a painful unconditioned stimulus), or ii) unpaired (CS?). During acquisition phase, participants watched their hand as they moved it. Participants were randomly allocated to an Imprecise group, for whom visual feedback of the hand was offset 30 to 50 mm from its true location, or a Precise group, for whom vision was not disrupted. In the test phase, participants moved their hands to 5 locations—the CS+, CS?, and 3 locations that lay between the 2 (“generalization stimuli”). Our primary hypothesis was supported—pain expectancy was greater at the CS+ location in the Imprecise group than in the Precise group (6.9 [SD = 1.9] vs 5.4 [SD = 2.5], P= .02). Pain expectancies generalized to novel locations similarly in both groups and there was no difference in extinction between groups. Our primary hypothesis was supported but our subsequent hypotheses were not.PerspectiveWe conditioned pain expectancy at a certain location of one hand, even though most participants were unaware of the contingency. Conditioned pain expectancy was greater when sensory information about location was less precise. This adds support to the possibility that associative learning may play a role in the progression of an acute pain episode to a more generalized pain disorder.  相似文献   
588.
目的:观察米帕明对局灶性脑缺血再灌注大鼠脑组织中含一氧化氮浓度和一氧化氮合酶活性的影响。方法:实验于2005-03/12在解放军总医院老年心血管病研究所生化药理实验室进行。①选用健康Wistar大鼠96只,随机分成假手术组、模型组、尼莫地平组和米帕明组4组,每组24只。②米帕明组腹腔注射米帕明10mg/kg,尼莫地平组腹腔注射尼莫地平2mg/kg,假手术组和模型组腹腔注射等容积生理盐水;60min后用线栓法建立大鼠局灶性脑缺血-再灌注损伤模型,假手术组尼龙线的头端不插入颈内动脉。③于缺血2h再灌注2,12和24h每组随机取6只大鼠断头,测定脑组织中一氧化氮浓度和一氧化氮合酶活性。每组剩余6只再灌注2h处死取脑,光镜下观察脑组织病理变化。结果:96只大鼠进入结果分析。①一氧化氮浓度:模型组、尼莫地平组和米帕明组再灌注2,12和24h均高于假手术组(P<0.05);尼莫地平组再灌注2,12和24h均低于模型组[(45.99±8.13),(40.63±3.13),(36.72±4.38)μmol/L;(65.54±6.01),(57.08±4.79),(48.13±5.12)μmol/L;P均<0.05];米帕明组再灌注2h和24h也低于同期模型组[(55.98±6.89),(39.42±4.28)μmol/L;P均<0.05]。②一氧化氮合酶活性:模型组、尼莫地平组和米帕明组再灌注2,12和24h均高于假手术组(P<0.05);尼莫地平组和米帕明组各个时间点均低于模型组(P<0.05)。③脑组织病理变化:尼莫地平组和米帕明组神经元损伤较模型组轻。结论:米帕明可降低局灶性脑缺血再灌注大鼠脑组织中一氧化氮浓度和一氧化氮合酶活性,从而对大鼠脑缺血再灌注有保护作用,其效果与尼莫地平相似。  相似文献   
589.
BACKGROUND: Glycolic acid and Jessner's solution are popular superficial chemical peel agents for the treatment of facial acne, and increased sebum secretion is one of the major aetiological factors of acne. OBJECTIVE: To compare the effects of 30% glycolic acid peels and Jessner's solution peels on sebum secretion in facial acne patients. METHODS: Thirty-eight patients with mild to moderate facial acne were included. Twenty-seven patients were treated with 30% glycolic acid peels and 11 patients with Jessner's solution peels. Each peel was performed twice with an interval of 2 weeks. Before and 2 weeks after each peel, sebum levels of forehead, nose, chin and cheeks were measured by using a Sebumeter (SM810 Courage & Khazaka, Cologne, Germany). RESULTS: The sebum levels were not significantly changed by two peels treatments of 30% glycolic acid peels or Jessner's solution peels on the facial skins of patients with facial acne. CONCLUSIONS: The two types of peels, 30% glycolic acid peels and Jessner's solution peels, did not affect sebum secretion of the facial skins of patients with facial acne after the two peels treatments. The accumulative effects of more than two peels treatments using these modalities need further evaluation.  相似文献   
590.
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