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排序方式: 共有1437条查询结果,搜索用时 218 毫秒
1.
孕期贫血会导致各种妊娠不良结局,如早产,出血耐受性降低,产后出血甚至失血性休克,产褥感染,以及新生儿低体重,新生儿死亡等,严重危害母胎健康。我国妊娠期铁缺乏和缺铁性贫血诊治指南建议通过积极监测血红蛋白及血清铁,加强饮食补铁,预防孕期贫血,从而避免不良妊娠结局的发生。 相似文献
2.
《Journal of pharmaceutical sciences》2019,108(10):3425-3433
This study aimed at evaluating how encapsulation in a regular nanocarrier (NC) (providing extended circulation time) or in a brain-targeting NC (providing prolonged circulation time and increased brain uptake) may influence the therapeutic index compared with the unformulated drug and to explore the key parameters affecting therapeutic performance using a model-based approach. Pharmacokinetic (PK) models were built with chosen PK parameters. For a scenario where central effect depends on area under the unbound brain concentration curve and peripheral toxicity relates to peak unbound plasma concentration, dose-effect and drug-side effect curves were constructed, and the therapeutic index was evaluated. Regular NC improved the therapeutic index compared with the unformulated drug due to reduced peripheral toxicity, while brain-targeting NC enhanced the therapeutic index by lowering peripheral toxicity and increasing central effect. Decreasing drug release rate or systemic clearance of NC with drug still encapsulated could increase the therapeutic index. Also, a drug with shorter half-life would therapeutically benefit more from a NC encapsulation. This work provides insights into how a NC for brain delivery should be optimized to maximize the therapeutic performance and is helpful to predict if and to what extent a drug with certain PK properties would obtain therapeutic benefit from nanoencapsulation. 相似文献
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4.
Anne T. Berg Shlomo Shinnar‡§ Eugene D. Shapiro Morton E. Salomon‡ Ellen F. Crain‡ W. Allen Hauser§ 《Epilepsia》1995,36(4):334-341
Summary We conducted a matched casecontrol study to identify risk factors for first febrile seizures, with special emphasis on characteristics of the acute illness episode. Cases were identified through hospital emergency departments; controls were identified through outpatient clinics and emergency departments. Sixtynine children with first febrile seizures and no history of previous unprovoked seizures were matched for age (±6 months), site of routine pediatric care, and date of visit (±weeks) with 1 or 2 febrile controls who had no history of previous febrile or unprovoked seizures. Medical records for the index visit were reviewed, and parents were interviewed by telephone. Illness characteristics examined included height of temperature, type of underlying illness, contact with a physician during the illness but before the index visit, and use of acetaminophen or decongestants. Family history of febrile and of unprovoked seizures, sociodemographic characteristics, daycare use, and selected preand perinatal variables were also studied. On multivariable analysis, significant independent risk factors were height of temperature, history of febrile seizures in a firstor in a higher degree relative. Gastroenteritis as the underlying illness had a significant inverse (i.e., protective) association with febrile seizures. Maternal smoking during pregnancy was a marginally significant predictor of febrile seizures. 相似文献
5.
Background: Mivazerol is a new and selective α2-adrenoceptor agonist, devoid of hypotensive effects, which has been designed to prevent adverse cardiac outcome in perioperative patients with, or at risk of coronary artery disease. Methods: In the present study, the effects of mivazerol on hemodynamic changes induced by trachea-exposure surgery stress were investigated in pentobarbital-anesthetized rats, and compared to those of dexmedetomidine. Results: Intravenous infusion of 3 different doses of mivazerol (3.75, 7.5 and 15 μg kg-1 h-1) did not significantly alter BP but caused a dose-related decrease in HR. The maximal decrease in HR was approximately 87 beats/min. Contrary to mivazerol, dexmedetomidine (7.5 μg kg-1 h-1, i.v.) decreased both BP (11±3.2 mmHg) and HR. The maximum decrease in HR was approximately 104 beats/min. Surgical stress produced a rapid increase in BP (maximal increase of 50 mmHg) and HR (maximal increase of 100 beats/min), which lasted for at least 15 min. Constant infusion of mivazerol, at a dose of 15 μg kg-1 h-1, beginning 20 min prior to surgery and lasting for 35 min, significantly inhibited surgical stress-induced increases in BP (P < 0.05) and HR (P < 0.001). Dexmedetomidine, at a dose which produced hypotension and profound bradycardia prior to surgery, did not have any effect on the surgical stress-induced elevation in BP (P>0.05), but prevented the increase in HR (P < 0.05). Pretreatment with the α2-adrenoceptor antagonist rau-wolscine (0.5 mg/kg, i.v.) blocked the bradycardia induced by mivazerol as well as the inhibitory effect of mivazerol on surgical stress-induced elevations in HR and BP. Conclusion: Mivazerol attenuates surgical stress-induced elevations in BP and HR during pentobarbital anesthesia in rats, and these effects are mediated by stimulation of α2-adrenoceptors. Unlike dexmedetomidine, mivazerol does not reduce BP, and is also more potent than dexmedetomidine in blunting surgical stress-induced increases in BP in pentobarbital-anesthetized rats. 相似文献
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7.
Numerous studies show that breastfeeding is beneficial to both mothers and babies. This study explores two understudied correlates that may influence breastfeeding initiation: intimate partner violence during pregnancy and early postnatal depressive symptoms. A cross-sectional comparative study design investigated the correlates of feeding modes of 1200 Chinese mother and infant pairs in a university-affiliated regional hospital in Hong Kong. The prevalence rates of breastfeeding and mixed feeding were 42.25% and 26.25%, respectively. Women who had no experience of intimate partner violence during pregnancy were significantly more likely to initiate breastfeeding (adjusted odds ratio = 1.84; 95% confidence interval, 1.16-2.91) after adjustment for demographic, socioeconomic, and obstetric variables. Early postnatal depressive symptoms were not significantly associated with feeding modes in a multinomial logistic regression model. Midwives are in a key position to identify and intervene to encourage more successful breastfeeding practice. 相似文献
8.
To examine effects of lung motion on the separation of pleural surfaces during breathing, we modeled the pleural space in two dimensions as a thin layer of fluid separating a stationary elastic solid and a sliding flat solid surface. The undeformed elastic solid contained a series of bumps, to represent tissue surface features, introducing unevenness in fluid layer thickness. We computed the extent of deformation of the solid as a function of sliding velocity, solid elastic modulus, and bump geometry (wavelength and amplitude). For physiological values of the parameters, significant deformation occurs (i.e. bumps are 'flattened') promoting less variation in fluid thickness and decreased fluid shear stress. In addition, deformation is persistent; bumps of sufficient wavelength, once deformed, require a recovery time longer than a typical breath-to-breath interval to return near their undeformed configuration. These results suggest that in the pleural space during normal breathing, separation of pleural surfaces is promoted by the reciprocating sliding of lung and chest wall. 相似文献
9.
目的 观察休克期大面积切痂对严重烧伤大鼠细胞免疫功能的影响,探索改善烧伤后机体免疫功能紊乱的有效方法。方法 将大鼠分成休克期切痂组(A组)、常规切痂组(B组)和正常对照组(C组)。A、B组造成30%TBSAⅢ度烫伤,C组不烫伤。A组伤后第6h、B组伤后第4d切痂,并于伤后第1、5、9d各活杀10只,取材送检,观察其免疫指标的变化。结果 (1)A、B组与C组比较:A、B组烫伤大鼠各时相点CD3^+T细胞变化不大(P〉0.05),但CD4^+T细胞、CD4^+/CD8^+比值明显下降、CD8^+T细胞增高(P〈0.05或P〈0.01)。NK细胞活性明显下降(P〈0.05或P〈0.01),外周血CD25^+T淋巴细胞表达及经活化后脾脏CD25^+T淋巴细胞表达明显下降(P〈0.05或P〈0.01)。(2)A组与B组比较:A组CD4^+T细胞、CD4^+/CD8^+比值明显升高、CD8^+T细胞降低(P〈0.05或P〈0.01),NK细胞活性明显升高(P〈0.05或P〈0.01),外周血CD25^+T淋巴细胞表达及经活化后脾脏CD25^+T淋巴细胞表达均明显升高(P〈0.05或P〈0.01)。结论 (1)大鼠烫伤后细胞免疫状况发生了明显变化。(2)休克期切痂可以改善烫伤大鼠T淋巴细胞亚群分布,提高NK细胞活性,增加外周血CD25^+T淋巴细胞的表达。提高经活化后脾脏CD25^+T淋巴细胞数。从而改善烫伤大鼠伤后机体的细胞免疫功能。 相似文献
10.
M. M. Cohen B. Schei D. Ansara R. Gallop N. Stuckless D. E. Stewart 《Archives of women's mental health》2002,4(3):83-92
Summary
Background: A link between violence and depression has been shown, but not a link between violence and postpartum depression. This study
sought to determine if there is an association between a history of abuse (physical, sexual, emotional as a child or adult)
and postpartum depression (PPD).
Method: 200 postpartum women were recruited from 6 hospitals. At 8–10 weeks postpartum, a telephone interviewer asked women about
physical, emotional or sexual abuse as an adult or child and sociodemographic, obstetrical and personal medical history. PPD
was assessed using the Edinburgh Postnatal Depression Scale (EPDS, score of ≥12). Abuse was determined by the Conflict Tactics
Scale or the Abuse Assessment Screen. Chi-square and logistic regression were used to determine the relationship between violence
and PPD.
Results: 11% of women had EPDS scores of ≥12. Rates of childhood (6.5%), or adult (6.5%) physical abuse; and childhood (13%) or adult
(14%) sexual abuse were reported by respondents. Emotional abuse in the current relationship (29.6%) exceeded that of childhood
abuse (3.5%). Overall 43.2% of respondents had at least one form of abuse. Having a history of depression (OR = 3.3 (95% CI,
1.3–8.7)), panic attack during pregnancy (OR = 5.4 (1.6–19.0)), maternal complications (OR = 5.0 (1.7–15.1)), low social support
(OR = 3.3 (1.3–8.7)) and emotional abuse (OR = 2.8 (1.1–7.4) were associated with PPD.
Conclusion: Emotional abuse but not physical or sexual abuse was found to be associated with PPD. A possible explanation for this relationship
may be that being in an abusive situation puts one at risk for depression and in turn, postpartum depression. 相似文献