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21.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
22.
Coirini H Gouézou M Liere P Delespierre B Pianos A Eychenne B Schumacher M Guennoun R 《Neuroscience》2002,113(4):883-891
In adult male rats, 3beta-hydroxysteroid dehydrogenase/delta5-delta4-isomerase (3beta-HSD) expressing cells were identified in the spinal cord from the cervical to the sacral segments. An in situ hybridization study, using an oligonucleotide common to the four known isoforms of rat 3beta-HSD, revealed its mRNA in gray matter. Measurements of optical densities in autoradiograms showed the following regional distribution: dorsal horn (layers I-III) > central canal (layer X) > or = ventral horn (layers VIII-IX) > ventral funiculus = lateral funiculus. At the cellular level, the number of grains was higher on the large motoneurons than on small neurons of the dorsal horn, but the grain density per cell was similar. Further evidence for the expression of 3beta-HSD in the spinal cord was obtained by western blot analysis, which revealed an immunoreactive protein of approximately 45 kDa in the dorsal and ventral parts of the spinal cord. Castration and adrenalectomy did not influence the expression of 3beta-HSD mRNA and protein. Gas chromatography/mass spectrometry measurements showed higher levels of pregnenolone and progesterone in the spinal cord than in the plasma. After castration and adrenalectomy, their levels remained elevated in the spinal cord, suggesting that these neurosteroids may be synthesized locally. The wide distribution of 3beta-HSD, and the high levels of pregnenolone and progesterone in the spinal cord even after castration and adrenalectomy, strongly suggest a potential endogenous production of progesterone and an important signalling function of this steroid in the spinal cord. 相似文献
23.
A model of corrective gene transfer in X-linked ichthyosis 总被引:5,自引:0,他引:5
Freiberg RA; Choate KA; Deng H; Alperin ES; Shapiro LJ; Khavari PA 《Human molecular genetics》1997,6(6):927-933
Single gene recessive genetic skin disorders offer attractive prototypes
for the development of therapeutic cutaneous gene delivery. We have
utilized X-linked ichthyosis (XLI), characterized by loss of function of
the steroid sulfatase arylsulfatase C (STS), to develop a model of
corrective gene delivery to human skin in vivo. A new retroviral expression
vector was produced and utilized to effect STS gene transfer to primary
keratinocytes from XLI patients. Transduction was associated with
restoration of full-length STS protein expression as well as steroid
sulfatase enzymatic activity in proportion to the number of proviral
integrations in XLI cells. Transduced and uncorrected XLI keratinocytes,
along with normal controls, were then grafted onto immunodeficient mice to
regenerate full thickness human epidermis. Unmodified XLI keratinocytes
regenerated a hyperkeratotic epidermis lacking STS expression with
defective skin barrier function, effectively recapitulating the human
disease in vivo. Transduced XLI keratinocytes from the same patients,
however, regenerated epidermis histologically indistinguishable from that
formed by keratinocytes from patients with normal skin. Transduced XLI
epidermis demonstrated STS expression in vivo by immunostaining as well as
a normalization of histologic appearance at 5 weeks post-grafting. In
addition, transduced XLI epidermis demonstrated a return of barrier
function parameters to normal. These findings demonstrate corrective gene
delivery in human XLI patient skin tissue at both molecular and functional
levels and provide a model of human cutaneous gene therapy.
相似文献
24.
应用WGA-HRP顺行轴突运输研究大鼠视前内侧区传出性神经纤维投射。结果表明:视前内侧区的上行投射向嘴侧经斜角带进入外侧隔核;经髓纹进入缰核;经无名质进入杏仁前区及经终纹进入杏仁内侧核,另有标记纤维经内侧前脑束向外下行,经视束上方进入杏仁内侧核。下行投射经内侧前脑束进入下丘脑室旁核、外侧区、内侧核、后核、弓状核、乳头体前腹核和乳头体上核。继续向尾侧,标记纤维进入中脑腹侧背盖区,并投射到中缝正中核及中缝背核。 相似文献
25.
Yann Gouëffic Jean L. Pin Jean Sabatier Yves Alimi Eric Steinmetz Pierre-Edouard Magnan Olivier Marret Adrien Kaladji Bertrand Chavent Benjamin Kretz Alexandra Jobert Solène Schirr-Bonnans Béatrice Guyomarc'h Valéry P. Riche Lucie S. du Mont Philippe Tessier 《European journal of vascular and endovascular surgery》2021,61(3):447-455
26.
Frederick H Koh Jason MW Chua Joselyn LJ Tan Fung-Joon Foo Winson J Tan Sharmini S Sivarajah Leonard Ming Li Ho Bin-Tean Teh Min-Hoe Chew 《World journal of gastrointestinal surgery》2021,13(8):734-755
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view. 相似文献
27.
目的 构建半水硫酸钙和纳米羟基磷灰石为主的复合人工骨材料并对其注射性能、凝固性能和机械强度的影响因素进行考察.方法 测试不同液固比条件下复合材料的注射特性,25℃和37℃时分别测试不同液固比、不同二水硫酸钙促凝剂条件下的材料初、终凝时间和压缩强度,均与纯硫酸钙作对比.结果 液固比0.50以上时注射性能满意.无论何种液/固比,复合材料的凝固时间均较硫酸钙延长,37℃下的凝固时间较25℃下延长.一定范围内促凝剂用量过大或过小均使凝固时间延长.液固比越大或促凝剂用量越高,材料压缩强度越低.纳米磷灰石含量增大则材料强度降低.结论 合理掌握纳米磷灰石的比例,液固比和促凝剂的用量,是开发可注射纳米人工骨的关键. 相似文献
28.
Internet网上细胞凋亡研究的信息资源及其利用 总被引:1,自引:0,他引:1
0 引言 Internet网上含有丰富的信息资源 ,科研人员可以通过 Internet网了解其所研究领域的最新发展动态 ,获取全面和系统的科研信息 ,有利于进行学术交流[1 ] .然而网上信息浩如烟海 ,当检索某一专门领域的资料时 ,有时无从下手 .我们在科研实践中对 Internet网上主要的细胞凋亡研究信息资源及其查找方法进行了归纳 .1 细胞凋亡专业网站1. 1 The Cell death society (http:/ / www.celldeath-apoptosis.org) 为美国细胞死亡学会主办 ,概括了细胞凋亡和程序性细胞死亡研究的各个领域 ,包括与细胞凋亡有关的各种疾病 .可以免费注册… 相似文献
29.
帕司烟肼介入凝胶体外抗结核活性及安全性研究 总被引:1,自引:0,他引:1
目的 观察帕司烟肼凝胶体外抗结核作用和支气管介入的安全性。方法 手工法、仪器法分别测定帕司烟肼及其凝胶的最小抑菌浓度和最小杀菌浓度及家兔经支气管介入的安全性试验。结果 帕司烟肼凝胶对H37Rv标准株、牛型结核分枝杆菌、草分枝杆菌MIC值分别为0.1、0,1、0.4mg/L,MBC值分别为0,2、0.2和1.6mg/L;帕司烟肼凝胶与帕司烟肼单体MIC、MBC值无显著差异;动物实验表明该药应用安全。结论 帕司烟肼凝胶具有与帕司烟肼单体相同的抗结核菌药效,卡波姆基质不影响帕司烟肼的抗菌活性;以卡波姆为基质的帕司烟肼凝胶应用安全。 相似文献
30.