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41.
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   
42.
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   
43.
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   
44.
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   
45.
研究了不同温度、浓度条件下,顺丁烯二酸(顺酸)非催化反应网络,即顺酸可生成反丁烯二酸(反酸)和苹果酸,反酸与苹果酸存在可逆反应。建立了该反应网络的动力学模型。测定了不同反应条件下顺酸、反酸和苹果酸浓度随时间变化的规律,据此,动力学参数进行了估值。  相似文献   
46.
C. de  Vroey  A. Lasagni  E. Tosi  F. Schroeder  M. Song 《Mycoses》1992,35(7-8):193-196
Microascus cirrosus is very rarely the aetiological agent of onychomycosis. We report two additional cases of toenail infections caused by this fungus.  相似文献   
47.
为探讨人食管癌组织中热休克蛋白 70 (HSP70 )和糖调节蛋白 94( grp94)的表达及意义 ,采用SABC法检测人食管癌组织HSP70和grp94的表达 ,镜下观察HSP70和 grp94在癌组织及癌旁组织中的表达特点。结果 :92 .6%( 5 0 /5 4)食管癌组织中存在HSP70的表达 ,癌细胞存在胞质、胞核表达强度及部位的差异 ;而 grp94的表达阳性率为70 .4% ( 3 8/5 4) ,以胞质表达为主 ,而癌旁组织表达较少。提示 :人食管癌组织存在HSP70和 grp94的表达异质性 ,呈现了胞质、胞核的表达差异 ,HSP70和 grp94在人食管癌组织的表达特点为以后肿瘤抗原肽肿瘤疫苗的提取和实验奠定了基础。  相似文献   
48.
A method for dynamic imaging in MRI is presented that enables the acquisition of a series of images with both high temporal and high spatial resolution. The technique, which is based on the projection reconstruction (PR) imaging scheme, utilizes distinct data acquisition and reconstruction strategies to achieve this simultaneous capability. First, during acquisition, data are collected in multiple undersampled passes, with the view angles interleaved in such a way that those of subsequent passes bisect the views of earlier ones. During reconstruction, these views are weighted according to a previously described k-space weighted image contrast (KWIC) technique that enables the manipulation of image contrast by selective filtering. Unlike conventional undersampled PR methods, the proposed dynamic KWIC technique does not suffer from low image SNR or image degradation due to streaking artifacts. The effectiveness of dynamic KWIC is demonstrated in both simulations and in vivo, high-resolution, contrast-enhanced imaging of breast lesions.  相似文献   
49.
探讨人工心脏起搏器植换方式选择。方法:起搏器植换22例,其中,能源耗竭14例,感知和起搏功能障碍4例,囊袋感染破溃致PM外露4例。非感染者起搏阈值,〈2.5V,行原位植换:PT值〉3.0V或有感染者,更换全套起搏系统。结果:非感染的18例中,10例PT〈2.5V,实行原位植换;8例PT值〉3.0V和其余4例有感染者,植入新的起搏系统。  相似文献   
50.
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