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71.
Slocum JM Sosa ME 《The Journal of perinatal & neonatal nursing》2002,16(2):40-53; quiz 2 p following 84
Prior to the discovery of insulin, the combination of diabetes and pregnancy was considered potentially lethal. Advances in the care of diabetes, combined with advances in antepartum fetal testing, have reduced maternal and perinatal mortality outcomes to levels expected in nondiabetic pregnancies. As new oral antidiabetes medications are introduced, the safety and efficacy of using them during pregnancy are under investigation. This article describes the oral medications currently available to treat diabetes, reviews the body of research available on these agents, and discusses current recommendations and controversies. 相似文献
72.
A flexible approach to response surface modeling for the study of the joint action of three active anticancer agents is used to model a complex pattern of synergism, additivity and antagonism in an in vitro cell growth assay. The method for determining a useful nonlinear response surface model depends upon a series of steps using appropriate scaling of drug concentrations and effects, raw data modeling, and hierarchical parameter modeling. The method is applied to a very large in vitro study of the combined effect of Trimetrexate (TMQ), LY309887 (LY), and Tomudex (TDX) on inhibition of cancer cell growth. The base model employed for modeling dose-response effect is the four parameter Hill equation [1]. In the hierarchical aspect of the final model, the base Hill model is treated as a function of the total amount of the three drug mixture and the Hill parameters, background B, dose for 50% effect D50, and slope m, are understood as functions of the three drug fractions. The parameters are modeled using the canonical mixture polynomials from the mixture experiment methodologies introduced by Scheff [2]. We label the model generated a Nonlinear Mixture Amount model with control observations, or zero amounts, an "NLMAZ" model. This modeling paradigm provides for the first time an effective statistical approach to modeling complex patterns of local synergism, additivity, and antagonism in the same data set, the possibility of including additional experimental components beyond those in the mixture, and the capability of modeling three or more drugs. 相似文献
73.
In order to examine the intracellular locus of the folic acid (PteGlu)-enhanced synergies of trimetrexate (TMQ) plus the thymidylate synthase (TS) inhibitor, raltitrexed (RTX), and TMQ plus the glycinamide ribonucleotide formyltransferase (GARFT) inhibitor, AG2034, comprehensive protection studies with thymidine (dThd) and hypoxanthine (HX) were conducted in a 96-well plate cell growth inhibition (sulforhodamine B) assay. Current modeling techniques were extended to characterize these protection patterns involving multiple-agent interaction. Wild-type human ileocecal HCT-8 cells and DW2, a subline deficient in folylpoly-gamma-glutamate synthetase (FPGS) were individually treated for 96 h with TMQ, AG2034 and a 1:1 mixture of TMQ:AG2034 or with TMQ, RTX, and a 1:1 mixture of TMQ:RTX in the presence of PteGlu (2.3 or 40 micro M) and the protection agents (10 micro M dThd and/or 100 micro M HX). Drug treatments were randomly assigned to wells. Both isobols and 3-dimensional concentration-effect surfaces were used to assess the nature and the intensity of drug interactions. The structural Hill model was fitted to data with weighted non-linear regression for most cases. A so-called 'double Hill' model was sometimes more appropriate when a plateau in the middle of the concentration-effect curve was found. In HCT-8 and DW2 cells at 2.3 and 40 micro M PteGlu, inhibition of DHFR by TMQ induced antithymidylate and antipurine effects; AG2034 and RTX selectively inhibited de novo purine or thymidine synthesis, respectively. dThd protection increased the PteGlu-enhancement of the TMQ + AG2034 synergy, whereas HX protection increased the PteGlu-enhancement of the TMQ + RTX synergy. The PteGlu-enhanced synergies of TMQ + AG2034 and TMQ + RTX occur primarily through inhibition of purine synthesis and inhibition of thymidylate synthesis, respectively. These results further substantiate the hypothesis that the nonpolyglutamylatable DHFR inhibitor, TMQ, acts as a modulator by decreasing the protection by PteGlu of cells against the polyglutamylatable AG2034 and RTX. 相似文献
74.
Judith H. Gibbs Chloe Fisher Sunita Bhattacharya Peter Goddard J.D. Baum 《Early human development》1977,1(3):227-245
"Drip breast milk" is that milk which spontaneously drips from the contralateral breask during the suckling of an infant. Biochemically and immunologically, pooled drip milk resembled pooled mature expressed breast milk, although it has a lower fat concentration. About 15% of lactating women are capable of producing drip milk; volumes produced are up to 188 ml/donor/day. A milk bank is described which processes 1400 liters of drip milk/yr. Heat treatment of this milk with a semi-automated holder pasteurizer caused a 21% reduction in IgA concentration and a 36% reduction in lysozyme activity, as well as a decrease in the ability of the milk to inhibit the growth of E. coli. In comparison with boiling, pasteurization was as effective in reducing total bacterial content provided the milk initially contained fewer than 10(6) bacteria/ml. 相似文献
75.
Michael L. Lipton Chloe Ifrah Walter F. Stewart Roman Fleysher Martin J. Sliwinski Mimi Kim Richard B. Lipton 《Journal of Science and Medicine in Sport》2018,21(4):363-367
Objectives
To validate the HeadCount-2w questionnaire for estimation of 2-week soccer heading by comparison to daily electronic diary reporting over the same two-week period.Design
Prospective observational study.Methods
Adult amateur soccer players completed HeadCount-daily, comprising 14 daily at-home assessments of soccer play and heading via a tablet PC. Following the 14 day period, players completed HeadCount-2w, a web-based two-week-recall questionnaire on soccer and heading. intraclass correlation coefficient (ICC) was estimated between HeadCount-daily, the reference standard, and HeadCount-2w estimates of heading during the same 2-week period.Results
53 participants (38 men) reported a mean of 24.36 (median = 11.76) headers during 2 weeks via HeadCount-daily and a mean of 38.34 (median = 15.0) headers for the same 2 weeks via HeadCount-2w. The ICC comparing 2-week heading from HeadCount-daily and HeadCount-2w was 0.85. Linear regression of the log-transformed Headcount-daily on HeadCount-2w data yielded a slope of 0.71 (p < 0.001; 95% CI 0.54–0.82), suggesting that heading tends to be over-estimated by HeadCount-2w relative to HeadCount-daily. Slope estimates for men (0.65) and women (0.71) were similar.Conclusions
HeadCount, a self-administered web-based survey, is valid for self-reporting 2-week heading in adult amateur players, supporting its use in future research and as a simple and low-cost technique for exposure monitoring. 相似文献76.
Chien C Li CI Heckbert SR Malone KE Boudreau DM Daling JR 《Breast cancer research and treatment》2006,95(2):131-140
Summary
Background Antidepressants are among the most commonly prescribed drugs in the United States. Laboratory studies suggest that because
certain antidepressants increase prolactin levels that they may also increase breast cancer risk. However, human studies evaluating
use of antidepressants in relation to breast cancer risk have yielded inconsistent results.
Methods A population-based case-control study consisting of 975 breast cancer cases 65–79 years of age diagnosed from 1997–1999 and
1007 age and residence-matched controls was conducted in western Washington State. Detailed information on antidepressant
use was obtained through structured in-person interviews. Logistic regression was performed to analyze the relationship between
antidepressant use and breast cancer risk.
Results Overall, there was no association between ever use of antidepressants and breast cancer risk (odds ratio [OR] = 1.2, 95% confidence
interval [95% CI]: 0.9–1.6). When evaluated separately, tricyclic antidepressants (TCA), selective serotonin reuptake inhibitors
(SSRI), and triazolopyridines were each not associated with breast cancer risk. However, risk varied by hormone receptor status.
Compared to never users, ever users of SSRIs had elevated risks of progesterone receptor (PR) negative and estrogen receptor
(ER) positive/PR-negative breast cancers (OR = 1.8, 95% CI: 1.1–3.6 and OR = 2.0, 95% CI: 1.1–3.8, respectively), but not
of tumors with other hormone receptor profiles.
Conclusions Based on these results and those of previous studies, there is limited evidence that any type of antidepressant use is associated
with breast cancer risk overall. SSRIs may elevate risks of PR- and ER+/PR- tumors, though further studies are needed to confirm
these associations. 相似文献
77.
Chloe Miu Mak Ching-Wan Lam Sidney Tam Ching-Lung Lai Lik-Yuen Chan Sheung-Tat Fan Yu-Lung Lau Sik-To Lai Patrick Yuen Joannie Hui Chun-Cheung Fu Ka-Sing Wong Wing-Lai Mak Kong Tze Sui-Fan Tong Abby Lau Nancy Leung Aric Hui Ka-Ming Cheung Chun-Hung Ko Yiu-Ki Chan Oliver Ma Tai-Nin Chau Alexander Chiu Yan-Wo Chan 《Journal of human genetics》2008,53(4):375-375
78.
79.
Gregoire Cosendai Chloe de Balthasar Anthony R. Ignagni Raymond P. Onders Kerry Bradley Kate Purnell J. Thomas Mortimer Ross Davis Yitzhak Zilberman Joe Schulman 《Neuromodulation》2005,8(3):203-211
Diaphragm pacing stimulation (DPS) for ventilator‐dependent patients provides several advantages over conventional techniques such as phrenic nerve pacing or mechanical ventilator support. To date, the only existing system for DPS uses lead electrodes, percutaneously attached to an external pulse generator (PG). However, for a widespread use of this technique it would be more appropriate to eliminate the need for percutaneous wire and use a totally implantable system. The aim of this study was to determine if it were feasible to replace the external PG by an implantable system. We present here the results of a preliminary study of two different PG, currently used in other electrical stimulation (ES) clinical applications, which could be used as implantable DPS systems. One radio‐frequency‐powered PG, one rechargeable battery‐powered PG, and the current external PG were tested. Each was attached to the externalized part of the wires, connected to the diaphragm and tidal volume (TV) was measured in one ventilator‐dependent patient who has been using the current percutaneous stimulator for 3 years. Results indicated that both implantable PGs could achieve equivalent ventilatory requirements to the current external stimulator. No significant differences were observed between the three PG systems when stimulating the electrodes as used in the patient's own chronically attached PG system. We found that TV increased with increases in charge and frequency as expected when stimulating the patient's electrodes individually and in combination with each PG system. These results are a significant step toward developing a totally implantable DPS system for the ventilator‐dependant patients. Further clinical tests to demonstrate the safety and efficacy of a fully implanted DPS system are warranted. 相似文献
80.
Prolonged exposure of humans to hypogravity causes weakening of their skeletal muscles. This problem was studied in rats exposed to hypogravity for 7 days aboard Spacelab 3. Hindlimb muscles were harvested 12-16 hours postflight for histochemical, biochemical, and ultrastructural analyses. The majority of the soleus and extensor digitorum longus fibers exhibited simple cell shrinkage. However, approximately 1% of the fibers in flight soleus muscles appeared necrotic. Flight muscle fibers showed increased glycogen, lower subsarcolemmal staining for mitochondrial enzymes, and fewer subsarcolemmal mitochondria. During atrophy, myofibrils were eroded by multiple focal losses of myofilaments; lysosomal autophagy was not evident. Tripeptidylaminopeptidase and calcium-activated protease activities of flight soleus fibers were significantly increased, implying a role in myofibril breakdown. Simple fiber atrophy appears to account for muscle weakening during spaceflight, but fiber necrosis is also a contributing factor. 相似文献