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101.
In order to determine the role of epidural anaesthesia on protein sparing, eighteen patients undergoing major visceral surgery were randomly divided into three different groups according to the mode of anaesthesia used (general anaesthesia, epidural anaesthesia, continuous epidural anaesthesia for 24 h). These patients were intravenously fed for five days postoperatively; their nitrogen balance was studied. Compared with the "general anaesthesia" group, only the daily averages of nitrogen balance of the "continuous epidural" group were significantly better. IN order to correlate stress with nitrogen saving, the early evolution of several parameters (cortisol, glucose, prolactin) used as "stress markers" was studied : there was no evidence of any significant difference between the three groups.  相似文献   
102.
Objectives

The purpose of this study was to examine differences between perceived harm of cigarette and electronic cigarette (e-cigarette) use while pregnant and differences between healthcare providers’ communication about these products during pregnancy.

Methods

A convenience sample of gestational women (n?=?218; ages 18–45) living in the US completed an online survey between May and December 2017. Participants reported perceived likelihood of adverse health outcomes (e.g., low birth weight, sudden infant death syndrome) among infants/children born to mothers who used cigarettes/e-cigarettes. T-tests and two-way ANOVAs examined differences between risk perceptions of using cigarettes/e-cigarettes while pregnant based on pregnancy status (previously pregnant, currently pregnant, future pregnant). Chi-square analyses examined differences between healthcare provider communication about cigarette/e-cigarette use during pregnancy.

Results

Overall, participants believed adverse health outcomes were significantly more likely to be caused by maternal use of cigarettes than e-cigarettes. Participants who planned to be pregnant reported higher endorsement that smoking combustible cigarettes would cause a miscarriage (p?<?.05) or increased blood pressure (p?<?.05) for a child than currently pregnant participants. Participants reported healthcare providers asked about (p?<?.05), advised them not to use (p?<?.001), and talked to them about health effects of smoking combustible cigarettes while pregnant (p?<?.001) significantly more than e-cigarettes.

Conclusions for Practice

Healthcare providers working with pregnant women should perform the 5As behavioral intervention method to provide pregnant women with tobacco cessation care. They should also discuss the absolute harm nicotine exposure (via cigarettes or e-cigarettes) can have on fetal health and development.

  相似文献   
103.
Objectives

Despite the obstacles of limited education and employment opportunities—and the stress associated with immigration and pregnancy—Mexican immigrant women have low rates of preterm birth (PTB) compared to the US national average for all races and ethnicities. Stressors during pregnancy, and stressors associated with acculturation, may accelerate cellular aging manifested by shortened telomere length (TL) in pregnant women. Our objectives were to: (1) determine whether women with PTBs had shorter telomere lengths compared to women who had full term births; (2) assess the association of acculturation with TL and PTB.

Methods

This prospective pilot study collected data from 100 self-identified Mexican-origin pregnant women. Survey data included self-administered sociodemographic and acculturation measures and was collected from participants via paper and pen, while biologic data was collected via a single blood draw during a regularly scheduled prenatal visit between 26 and 36 weeks gestation. PTB data was collected from the participant’s medical record after delivery.

Results

TL was significantly associated with PTB; the median TL of the women with PTB was less than the median TL for the full sample (p?=?0.02). Based on regression analysis for PTB vs acculturation, we found no significant associations between acculturation and PTB or TL.

Conclusions for Practice

This study provides important evidence of the association between shortened maternal TL and adverse birth outcomes. By linking social, clinical and biologic data, we can enhance our understanding of social determinants that may affect racial and ethnic disparities in preterm birth.

  相似文献   
104.
105.
Plasma protein extravasation has been measured in guinea pig skin using

-albumin and blood flow using

enon (

e) clearance. The nitric oxide (NO) synthase inhibitors NG-nitro-

-arginine methyl ester (

-NAME), NG-monomethyl-

-arginine (l

NMMA) and NG-nitro-

-arginine (

-NOArg) and the α-adrenoceptor agonist, phenylephrine, inhibited bradykinin induced plasma protein extravasation when co-injected with the peptide. The inhibitory effects of

-NAME and

-NOArg lasted for up to 8 and 4 h, respectively, whereas phenylephrine and

-NMMA had no persistent inhibitory effects. When co-injected with

e,

-NAME,

-NMMA,

-NOArg and phenylephrine, but not

-NAME, produced significant reductions in skin blood flow. When injected prior to

e,

-NAME and

-NOArg, but not phenylephrine or

-NMMA, significantly reduced flow. The effect of

-NAME on flow was not significant at 8 h. Thus, although the inhibitory effects of the NO synthase inhibitors on mediator induced plasma protein extravasation show correlations with their effects on blood flow, the persistent effect of

-NAME on exudation appears to extend beyond its effect on flow.  相似文献   
106.
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109.
Pluronic P-85 (poly(55)(oxypropylene)dipoly(s)(oxyethylene)) was used to form daunorubicin containing micelles. This new carrier was tested in vitro on sensitive and resistant ovarian cancer cell lines. Drug incorporation was measured by cytofluorometry and the cytotoxicity was measured by the tetrazolium formazan XTT assay. ID50 of 0.16 and 25 mu g/ml were obtained for conjugated and free daunorubicin respectively. The results obtained suggest that this approach may be used in combination with a chemotherapeutic agent to overcome multidrug resistance.  相似文献   
110.
OBJECTIVES. A nested case-control study was conducted in Miami, Fla, to determine risk factors associated with human immunodeficiency virus type 1 (HIV-1) seroconversion among injection drug users. METHODS. The study identified 21 incident cases of HIV-1 infection and 76 unmatched controls from two longitudinal cohorts of injection drug users. One cohort consisted of individuals who originally had been recruited from treatment centers; a second cohort was recruited from the "street." Logistic regression analyses that adjusted for age, gender, and race were performed. RESULTS. The final model determined that the primary independent risk factor that best explained the risk for seroconversion was sharing injection equipment in the year prior to conversion; a marginal risk factor was presence of sexually transmitted disease during this same period. CONCLUSIONS. Both an injection component and a sexual component play a role in seroconversion among injection drug users, although the injection component is much stronger.  相似文献   
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