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21.
We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without
disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional
CT images were invaluable in the diagnosis and assessment of this injury. 相似文献
22.
23.
Audit of oral anticoagulant treatment. The BCSH Haemostasis and Thrombosis Task Force of the British Society for Haematology.
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24.
Paul Preston 《Social science & medicine (1982)》1996,42(12):1681-1690
As interpreters for their deaf parents, hearing children are a cultural link between two often separate worlds: the Deaf and the Hearing. Data from a 4 year study of adult hearing children throughout the United States indicate significant differences between hearing daughters and hearing sons. Not only were daughters more likely than sons (regardless of birth order or age differences) to interpret for their parents, but daughters were also far more likely to be bilingual: fluent in both spoken English and American Sign Language. A similar gender bias has been observed among the general hearing public: women are far more likely to attend sign language classes and to work as interpreters for the deaf. This paper explores the social mechanisms and cultural values which determine the gender of the way we communicate with one another. Informants' narratives suggest that sign language and the practice of interpreting often touched upon a larger pattern of socialization and status differences between women and men. The discussion then turns to consider how these differences affect the cultural identity of hearing sons versus hearing daughters. 相似文献
25.
Brazell C Preston GC Ward C Lines CR Traub M 《Journal of psychopharmacology (Oxford, England)》1989,3(2):76-82
The transient impairments of memory produced by the muscarinic antagonist scopolamine have been adopted as a pharmacological model of Alzheimer-type dementia in normal volunteers. In this study we examined the effects of chronic (72 h) transdermal administration of scopolamine on memory, attention, sedation and visual function. The transdermal patches provided constant plasma levels of scopolamine for the duration of the study. Indices of the peripheral effects of scopolamine (visual near-point and pupil size) showed impairments that were sustained for 3 days. However, measures of sedation and memory revealed impairments that were maximal the day after patch application and which were no longer present 3 days after application. This pattern of results is discussed in relation to pharmacological modelling of Alzheimer's disease. 相似文献
26.
Candidate gene analysis in human neural tube defects 总被引:4,自引:0,他引:4
Boyles AL Hammock P Speer MC 《American journal of medical genetics. Part C, Seminars in medical genetics》2005,(1):9-23
Biochemical and developmental pathways, mouse models, and positional evidence have provided numerous candidate genes for the study of human neural tube defects. In a survey of 80 studies on 38 candidate genes, few found significant results in human populations through case-control or family-based association studies. While the folate pathway has been explored extensively, only the MTHFR 677C > T polymorphism was significant, and only in an Irish population. Developmental pathways such as the Wnt signaling pathway and Hox genes have also been explored without positive results. More than 90 mouse candidates have been identified through spontaneous and knockout mutations, but only the T locus (mouse Brachyury gene) showed association in an initial study that was not confirmed on follow-up. Positional candidates have been derived from cytogenetic evidence, but preliminary genomic screens have limited power due to small sample sizes. Future studies would increase their power to detect association by using more samples. In addition a clarification of the phenotype would be beneficial as many studies used different inclusion criteria. Incorporating several types of data could highlight better candidates, as would looking beyond the traditional sources for candidate genes. Recent studies of an energy metabolism gene (UCP2) and vitamin B metabolism (Transcoalbumin) have produced promising results. Utilizing other model organisms may also be beneficial, as in a recent study from a chick model of NTDs in NCAM1. New approaches combined with traditional methods and increased sample sizes will help prioritize human NTD candidate genes and clarify the complex etiology of this condition. 相似文献
27.
Cholinergic postganglionic neurones of the cardiac vagus in the toad, Bufo marinus, have been shown to contain the peptide somatostatin (SOM), which causes direct negative inotropic and chronotropic effects on the heart. In anaesthetised toads, high frequency stimulation (10 Hz) of cardiac vagus nerves results in prolonged cardiac slowing and potentiation of the cardiac slowing measured in response to a train of vagal stimuli at low frequency. Intravenous administration of the tetradecapeptide form of SOM also results in prolonged cardiac slowing and potentiation of cardiac vagal action. Effects on heart rate of small bolus doses of acetylcholine (ACh) were unaltered by administration of SOM, at the same time as cardiac vagal slowing was enhanced. It is suggested that SOM is released from vagal nerve endings by high frequency stimulation and enhances cardiac vagal action by a presynaptic mechanism. 相似文献
28.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献
29.
Permanent impairment of embryo development by hydrosalpinges 总被引:6,自引:9,他引:6
Recent reports suggest a deleterious effect of hydrosalpinges on pregnancy
outcome for in-vitro fertilization (IVF) and improvement following surgical
treatment. We compared the effect of hydrosalpinx on pregnancy outcome in
286 patients having 348 IVF cycles and followed the development of
untransferred embryos for 7 days to determine if hydrosalpinges affect
oocyte quality or embryo development. The delivery rate per retrieval was
significantly lower for patients with hydrosalpinx, but was restored by
surgical treatment to that of patients without hydrosalpinx. However, the
implantation rate per embryo transferred and normal blastulation of
untransferred embryos, which were significantly decreased in patients with
hydrosalpinx, and growth arrest and degeneration of untransferred embryos,
which were significantly increased compared to patients without
hydrosalpinx, were not restored by surgical treatment of hydrosalpinges. We
conclude that surgical treatment of hydrosalpinges decreases early
pregnancy loss and improves pregnancy outcome, possibly by diminishing
reversible deleterious effects exerted on the endometrium. As we have seen
in our laboratory, hydrosalpinges may have a permanent negative influence
on ovarian function, follicular development and oocyte quality since
implantation of transferred embryos and normal blastulation of
untransferred embryos remain low, and in-vitro growth arrest and
degeneration remain high despite surgical treatment of hydrosalpinges.
相似文献
30.