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51.
52.
Persistent genetic isolation in outport Newfoundland 总被引:2,自引:0,他引:2
J C Bear T F Nemec J C Kennedy W H Marshall A A Power V M Kolonel G B Burke 《American journal of medical genetics》1987,27(4):807-830
The historical development of genetic isolation has been evaluated for three outport Newfoundland study areas. An attempt was made to ascertain all livebirths in each study area, and determine the parentage of each. Data from records of baptism and marriage were used for this, supplemented with other historical and ethnographic information. Parent-offspring migration was used as a measure of genetic exchange between subpopulations within study areas, and gene flow into the study areas. Currently, 1-8% of parents originate outside the study areas; these rates are low compared to earlier periods, and compared to present-day rates for European isolate populations. Average kinship was estimated, to measure genetic relatedness within and between subpopulations of each area and the potential for random inbreeding; these values, which are minimum estimates, are now at historically high levels. Increased migration into the study areas, which would decrease average kinship, is not likely. Thus, any regionally or locally elevated frequencies of deleterious alleles will persist, and must be taken into account in providing genetic counseling and evaluating the utility of local screening programs. 相似文献
53.
In order to understand better the organisation of the ventral lateral geniculate nucleus of the ventral thalamus, this paper has examined the patterns of connections that this nucleus has with various nuclei of the dorsal thalamus in rats. Injections of biotinylated dextran or cholera toxin subunit B were made into the parafascicular, central lateral, posterior thalamic, medial dorsal, lateral dorsal, lateral posterior, dorsal lateral geniculate, anterior, ventral lateral, ventrobasal and medial geniculate nuclei of Sprague-Dawley rats and their brains were processed using standard tracer detection methods. Three general patterns of ventral lateral geniculate connectivity were seen. First, the parafascicular, central lateral, medial dorsal, posterior thalamic and lateral dorsal nuclei had heavy connections with the parvocellular (internal) lamina of the ventral lateral geniculate nucleus. This geniculate lamina has been shown previously to receive heavy inputs from many functionally diverse brainstem nuclei. Second, the visually related dorsal lateral geniculate and lateral posterior nuclei had heavy connections with the magnocellular (external) lamina of the ventral lateral geniculate nucleus. This geniculate lamina has been shown by previous studies to receive heavy inputs from the visual cortex and the retina. Finally, the anterior, ventral lateral, ventrobasal and medial geniculate nuclei had very sparse, if any, connections with the ventral lateral geniculate nucleus. Overall, our results strengthen the notion that one can package the ventral lateral geniculate nucleus into distinct visual (magnocellular) and non-visual (parvocellular) components. 相似文献
54.
The effect of reduced umbilical blood flow rate on fetal core temperature was investigated in five chronically instrumented fetal sheep (gestational age 124 days). On average, fetal-maternal temperature difference increased 0.13±0.02 °C when blood flow rate was decreased to about 1/3 of normal (248±69 ml min–1) for 30 min. The small temperature rise is the consequence of predominant heat dissipation through the placenta, and of diminished oxygen consumption. 相似文献
55.
Controlled study of withdrawal symptoms and rebound anxiety after six week course of diazepam for generalised anxiety 总被引:2,自引:0,他引:2
K G Power D W Jerrom R J Simpson M Mitchell 《British medical journal (Clinical research ed.)》1985,290(6477):1246-1248
A group of patients suffering from anxiety, as assessed by general practitioners and psychologists using research criteria for generalised anxiety, were treated with either diazepam or placebo double blind for six weeks. This active treatment period was preceded by a one week single blind placebo "wash in" period and followed by a two week single blind placebo "wash out" period. The results suggest that diazepam can produce rebound anxiety and withdrawal symptoms when used in moderate doses and for what has previously been regarded as a safe length of time. If replicated these results have implications for the therapeutic use of benzodiazepines. 相似文献
56.
A method for measurement of absolute cross-section areas in digital images of iodine-opacified vessels was tested in phantoms containing "normal" segments of circular cross-section and either circular or noncircular "stenoses" over a wide range of iodine concentrations. Accuracy varied with iodine concentration, with a slight tendency to overestimate the area at high concentration (185 mg I/ml) and to underestimate at low concentration (23 mg I/ml). Reproducibility was improved at the higher concentrations, with standard deviation ranging from 2% to 7% of the measured value, compared with 7% to 27% at the lowest concentration. Accuracy and reproducibility of area measurements on either normal or stenotic segments were unchanged by rotation of the vessel by up to 25 degrees out of the plane of the image. This method is easily implemented using computerized image processing techniques and has advantages over either manual or automated edge detection because it eliminates the need for an edge criterion and is independent of the viewing projection. 相似文献
57.
Power Thomas G. Garcia Karina Silva Martinez AnaMaria Diaz Parker Louise A. Hidalgo-Mendez Jackelyn Ramos Guadalupe 《Prevention science》2022,23(6):1018-1028
Prevention Science - “Madres Apoyando el Desarrollo Emocional de Sus Hijos” (“Mothers Supporting the Emotional Development of Their Children”) is a parenting... 相似文献
58.
生物技术是一门新兴的、综合的学科。生物技术在医药领域的应用涉及到新药开发、新诊断技术、预防措施及新的治疗技术。文章就以上方面做了扼要综述,展示了其广阔的应用前景。 相似文献
59.
Zaeem Lone Prithvi B. Murthy JJ Haijing Zhang Kyle J. Ericson Lewis Thomas Abhinav Khanna Georges-Pascal Haber Byron H. Lee 《Urologic oncology》2021,39(5):301.e1-301.e9
PurposeRenal function outcomes following robot-assisted radical cystectomy (RARC) have not been well established. We sought to compare long-term renal function outcomes between open radical cystectomy, RARC with extracorporeal urinary diversion and intracorporeal urinary diversion at a high volume institution.Materials and MethodsWe retrospectively reviewed our institutional bladder cancer database for patients who underwent RC from 2010 to 2019 with pre-operative estimated glomerular filtration rate (eGFR) > 45 ml/min/1.73m2. Changes in renal function were assessed through locally weighted scatter plot smoothing and comparison of median eGFR between surgical groups. Chronic Kidney Disease Stage 3B was defined as eGFR < 45 ml/min/1.73m2. Renal function decline was defined as a ≥10 ml/min/1.73m2 drop in eGFR. Kaplan Meier method with log-rank was used to compare CKD 3B-free survival and renal function decline. Cox Proportional Hazards model was used to identify predictors of CKD 3B.ResultsSix hundred and forty four patients were included with median follow-up of 32 months (IQR 12–56). Preoperative characteristics were similar among the groups with no differences in median pre-operative eGFR (ORC: 74.6, extracorporeal urinary diversion: 74.3, intracorporeal urinary diversion: 71.6 ml/min/1.73m2, P = 0.15). Median postoperative eGFR on follow up was not different between groups (P = 0.56). 33% of patients developed CKD 3B. There were no differences in CKD 3B-free survival by surgical approach (P = 0.23) or urinary diversion (P = 0.09). 64% of patients experienced renal function decline with a median time of 2.4 years (P 0.23). Predictors of CKD were pathologic T3 disease or greater (HR: 1.77, P = 0.01), ureteroenteric anastomotic stricture (HR: 2.80, P < 0.001), preoperative CKD Stage 2 (HR: 1.81, P =0.02), and preoperative CKD Stage 3A (HR: 5.56, P < 0.001).ConclusionRenal function decline is common after RC. Tumor stage, pre-operative eGFR, and ureteral stricture development, not surgical approach, influence renal function decline. 相似文献
60.
14 severely burned patients were randomly assigned to receive one of three nasogastric feeds commencing after the resuscitation period and continuing for 15 days. Group A received a feed with a high leucine content (31% of protein as branched chain amino-acids, BCAA). Group B received a similar feed to Group A but 65% of the leucine was replaced by alpha-ketoisocaproate (KIC). Group C received a whole protein feed (16% of the protein content as BCAA), and acted as a control group. Targeted energy intake was twice the calculated Basal Metabolic Rate (BMR). Group A had significantly reduced urinary 3-methylhistidine (3-MEH) and serum urea, compared with the control group. Serum total protein, albumin and transferrin and apparent nitrogen balance were not significantly different. Group B's results did not vary significantly from controls. Leucine enrichment reduces muscle protein breakdown benefiting burn patients fed enterally when compared to a standard feed, whereas KIC enrichment does not. 相似文献