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71.
Although breast milk is recommended as the optimal source of infant nutrition, breastfeeding initiation is below recommended levels, especially among teenage mothers. Breastfeeding initiation rates among Michigan (US) teenage mothers (12-19 y) were compared by demographics and health behaviors. Multivariate analyses determined which factors were significant independent predictors of breastfeeding initiation among teenage mothers enrolled prenatally in the Michigan Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in 1995. Significant predictors independently associated with breastfeeding initiation were race/ethnicity, education, marital status, postpartum anemia status, parity, prenatal trimester of WIC enrollment, and smoking. The strongest predictor of breastfeeding initiation differed for white mothers (positive predictor: education beyond high school [OR = 3.13]) and black mothers (negative predictor: multiparous [OR = 0.25]). Initiation rates for this population of teenage mothers fall below the national average for mothers of all ages and the US Healthy People 2010 goals. Research is needed concerning how breastfeeding support and education can be improved to reach the US national health goals.  相似文献   
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73.
目的 探讨急性脑梗死 (ACI)诱发全身炎症反应综合征 (SIRS)致多器官功能障碍综合征(MODS)的发病机制 ,以及血清肿瘤坏死因子 (TNF α)、白细胞介素 (IL 1) β含量变化在ACI诱发SIRS发生、发展并向MODS转化的临床意义。方法  6 8例ACI患者根据病情变化分为 3组 ,其中单纯性ACI(SACI组 ) 36例 ,ACI致SIRS(SIRS组 ) 32例 ,ACI致SIRS后发展为MODS(MODS组 ) 2 4例 ;应用酶联免疫吸附法 (ELISA法 )分别测定患者不同病程中血清TNF α、IL 1β值 ,并与对照组 (为 2 8名同期健康体检者 )比较。 结果  (1) 6 8例ACI中 4 7.0 6 %发生SIRS;SIRS时 75 %发生MODS。 (2 )血清TNF α、IL 1β的含量MODS 组 >SIRS组 >SACI组 >对照组 ,各组间比较 ,差异具有极显著性 (均P <0 0 1)。MODS重症者 (积分≥ 9分 )血清TNF α、IL 1β含量高于轻症者 (积分 <9分 ) (均P <0 0 1) ;MODS死亡者血清TNF α、IL 1β含量高于存活者 (均 P <0 0 1)。结论  (1)ACI后出现SIRS可导致MODS的发生。 (2 )患者血清TNF α、IL 1β水平异常变化可作为判断ACI致SIRS、MODS病情进展、预后及转归的一项指标  相似文献   
74.
目前口服避孕药(Ocs)在体外受精(IVF)周期中广泛应用,但各位学者研究结果不一.多数文献认为,口服避孕药应用于卵巢高反应和低反应患者可以改善体外受精临床结局,而口服避孕药应用于卵巢正常反应患者,除在促性腺激素释放激素拮抗剂(GnRHA)周期可通过其对月经周期进行控制,有计划地安排工作以外,并不改变体外受精临床结局.口服避孕药停药后5 d或月经第3天给促性腺激素(Gn)优于停药后2 d给促性腺激素.选择合理的口服避孕药用药方案和临床适应症对改善体外受精临床结局起着重要作用.  相似文献   
75.

Background  

To assess the nature, incidence, and risk factors of retinopathy associated with pegylated interferon and ribavirin combination therapy in chronic hepatitis C patients.  相似文献   
76.
77.
AIM To clone novel gastric cancer-associated genes and investigate their roles in gastric cancer occurrence.METHODS A method called differential display was used which allows the identification of differentially expressed genes by using PAGE to display PCR-amplified cDNA fragments between gastric cancer cells and normal gastric mucosa cells. These fragments were cloned into plasmid vector pUC18. Homology analysis was made after sequencing these fragments.RESULTS Two novel genes were identified compared with sequences from GenBank. One was registered with the AD number AF 051783. In situ hybridization showed that these two novel genes expressed specifically in gastric cancer tissues.CONCLUSION The two novel genes obtained by differential display were confirmed to be gastric cancer-associated genes using in situ hybridization.  相似文献   
78.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
79.
The differential effects of the pyrethroid tetramethrin on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) single sodium channel currents in rat dorsal root ganglion (DRG) neurons were investigated using the outside-out configuration of patch-clamp technique. Channel conductances were 10.7 and 6.3 pS for TTX-S and TTX-R sodium channels, respectively, at a room temperature of 24–26°C. The single-channel current of TTX-S sodium channels at the test potential of −30 mV was −1.27 ± 0.25 pA, and was not changed after exposure to 10 μM tetramethrin (−1.28 ± 0.23 pA). The open time histogram of TTX-S single-channel currents could be fitted by a single exponential function with a time constant of 1.27 ms. After exposure to 10 μM tetramethrin, the open time histogram could be fitted by the sum of two exponential functions with time constants of 1.36 ms (τfast) and 5.73 ms (τlow). The percentage of contribution of each component to the population was 62% for the fast component representing the normal channels and 38% for the slow component representing the tetramethrin modified channels. The amplitudc of TTX-R single-channel currents was slightly changed from −0.72 ± 0.14 to −0.83 ± 0.07 pA by 10 μM tetramethrin. The open time histogram of TTX-R single-channel currents could be fitted by a single exponential function with a time constant of 1.92 ms. In the presence of 10 μM tetramethrin, the open time histogram could be fitted by the sum of two exponential functions with time constants of 2.07 ms (τfast) and 9.75 ms (τslow). The percentage of contribution of each component was 15% for the fast, unmodified component and 85% for the slow, modified component. Differential effects of tetramethrin on the open time distribution of single sodium channel currents explains the differential sensitivity of TTX-S and TTX-R sodium channels.  相似文献   
80.
雷公藤总甙(TⅡ)中雷藤氯内酯醇的高效液相色谱分析   总被引:1,自引:0,他引:1  
建立了雷公藤总甙(T_1)中雷藤氯内酯醇的高效液相色谱分析方法。采用μ-Bondapak C_(18)柱和46%甲醇-水流动相,紫外检测波长219nm。考察了雷藤氯内酯醇的稳定性,雷藤氯内酯醇在0.5~10.0μg/ml范围内线性良好,回收率在98%~101%之间。  相似文献   
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