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排序方式: 共有2563条查询结果,搜索用时 42 毫秒
41.
Stanislav V Dryomov Azhar M Nazhmidenova Sophia A Shalaurova Igor V Morozov Andrei V Tabarev Elena B Starikovskaya Rem I Sukernik 《European journal of human genetics : EJHG》2015,23(10):1399-1404
The patterns of prehistoric migrations across the Bering Land Bridge are far from being completely understood: there still exists a significant gap in our knowledge of the population history of former Beringia. Here, through comprehensive survey of mitochondrial DNA genomes retained in ‘relic'' populations, the Maritime Chukchi, Siberian Eskimos, and Commander Aleuts, we explore genetic contribution of prehistoric Siberians/Asians to northwestern Native Americans. Overall, 201 complete mitochondrial sequences (52 new and 149 published) were selected in the reconstruction of trees encompassing mtDNA lineages that are restricted to Coastal Chukotka and Alaska, the Canadian Arctic, Greenland, and the Aleutian chain. Phylogeography of the resulting mtDNA genomes (mitogenomes) considerably extends the range and intrinsic diversity of haplogroups (eg, A2a, A2b, D2a, and D4b1a2a1) that emerged and diversified in postglacial central Beringia, defining independent origins of Neo-Eskimos versus Paleo-Eskimos, Aleuts, and Tlingit (Na-Dene). Specifically, Neo-Eskimos, ancestral to modern Inuit, not only appear to be of the High Arctic origin but also to harbor Altai/Sayan-related ancestry. The occurrence of the haplogroup D2a1b haplotypes in Chukotka (Sireniki) introduces the possibility that the traces of Paleo-Eskimos have not been fully erased by spread of the Neo-Eskimos or their descendants. Our findings are consistent with the recurrent gene flow model of multiple streams of expansions to northern North America from northeastern Eurasia in late Pleistocene–early Holocene. 相似文献
42.
The effect of synthetic GnRH on the synthesis of proteins and glycoproteins in the anterior pituitary and in vitro release of LH into the medium was studied. A maximal dose (25 ng/ml) of of synthetic GnRH caused optimum release of radioimmunoassayable LH into the medium after 2 h of incubation. A concomitant increase in cyclic AMP accumulation in the tissue and LH in the incubation medium was also observed under the influence of GnRH during different periods of incubation time. Incubation of the rat anterior pituitary with GnRH stimulated the incorporation of [3H] proline into acid precipitable proteins in a time- and dose-dependent manner, similar to radioimmunoassayable LH released into the medium. Similar results were obtained when pituitary was incubated with dibutyryl cyclic AMP. LH, in addition, enhanced the incorporation of [3H] glucosamine and [3H] amino acids mixture into acid-precipitable proteins suggesting that proteins including glycoproteins are synthesized by the rat anterior pituitary under the influence of GnRH. Approximately 10% of the radioactivity associated with proteins comigrated with radioimmunoassayable LH on the gels. GnRH also enhanced the incorporation of [3H] glucosamine and [3H] amino acid mixture into immunoprecipitable LH. The GnRH-induced incorporation of [3H] proline into anterior pituitary proteins was abolished by specific translation inhibitors. 相似文献
43.
Effect of defibrillation threshold testing on effectiveness of the subcutaneous implantable cardioverter defibrillator
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44.
Ahsan Azhar Angelique N. Wong Agustina A. Cerana Vishidha R. Balankari Madhuri Adabala Diane D. Liu Janet L. Williams Eduardo Bruera 《Journal of pain and symptom management》2018,55(5):1327-1334
Context
There is limited literature regarding outpatient palliative care and factors associated with unscheduled clinic visits.Objectives
To compare characteristics of patients with unscheduled vs. scheduled outpatient palliative care clinic visits.Methods
Medical records of 183 unscheduled cancer new outpatients and 104 unscheduled follow-up (FU) patients were compared with random samples of 361 and 314 scheduled new patients and FU patients, respectively. We gathered data on demographics, symptoms, daily opioid usage, and performance status.Results
Compared with scheduled new patients, unscheduled new patients had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P = 0.002), nausea (P = 0.016), depression (P = 0.003), anxiety (P = 0.038), drowsiness (P = 0.002), sleep (P < 0.001), and overall feeling of well-being (P = 0.001); had a higher morphine equivalent daily dose of opioids (median of 45 mg for unscheduled vs. 30 mg for scheduled; P < 0.001); and were more likely to be from outside the greater Houston area (P < 0.001). Most unscheduled and scheduled new and FU visits were for uncontrolled physical symptoms. Unscheduled FU patients, compared with scheduled FU patients, had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P < 0.001), depression (P = 0.002), anxiety (P = 0.004), drowsiness (P = 0.010), appetite (P = 0.023), sleep (P = 0.022), overall feeling of well-being (P < 0.001), and higher morphine equivalent daily dose of opioid (median of 58 mg for unscheduled FU visits vs. 40 mg for scheduled FU visits; P = 0.054).Conclusion
Unscheduled new FU patients have higher levels of physical and psychosocial distress and higher opioid intake. Outpatient palliative care centers should consider providing opportunities for walk-in visits for timely management and close monitoring of such patients. 相似文献45.
Hechter SJ Fredriksen PM Liu P Veldtman G Merchant N Freeman M Therrien J Benson L Siu S Webb G 《The American journal of cardiology》2001,87(5):660-3, A11
Angiotensin-converting enzyme inhibitors had no significant effect on cardiopulmonary exercise function in 14 patients who had undergone a Mustard operation for transposition of the great arteries. In some patients aerobic capacity improved and maximum systolic blood pressure decreased. 相似文献
46.
47.
The transport of cholesterol to the inner mitochondrial membrane, a key step in steroidogenesis, is subject to hormonal modulation that, at least in part, could be mediated by protein phosphorylation. This step is stimulated by sterol carrier protein 2 (SCP2) and Ca2+. To explore whether SCP2 itself is a potential control point for regulation by Ca2+-dependent phosphorylation we investigated whether highly purified SCP2 could serve as a substrate for major type Ca2+ and non-Ca2+-dependent protein kinases. Phosphorylation by calmodulin protein kinase II (CaM-PK II), myosin light chain kinase (MLCK), cAMP-dependent kinase (PKA) and protein kinase C (PKC) was monitored under optimal conditions for each enzyme. PKA, CaM-PK II and MLCK catalyzed the radiolabeling of histone 2A, synapsin I and myosin light chain (MLC), known substrates for these kinases, respectively, yet no phosphate transfer to SCP2 was observed. In contrast, PKC from two different sources (rat and calf brain) effectively catalyzed the phosphorylation of the highly purified SCP2. The phosphorylation of SCP2 depended on the addition of Ca2+ and phospholipids and was completely blocked by Polymyxin B, a PKC inhibitor. PKC catalyzed phosphorylation of SCP2 displayed a similar dependence on the concentration of ATP. Lineweaver Burk plots of the data indicate Km values for ATP of approximately 6 microM for the phosphorylation of SCP2. Our results, which have revealed for the first time that SCP2 is a substrate for PKC, are consistent with the possibilities that the control of steroidogenesis by tropic hormones and by PKC activation are mediated, at least in part, by the phosphorylation/dephosphorylation of SCP2. 相似文献
48.
B. Joseph Elmunzer Rebecca L. Spitzer Lydia D. Foster Ambreen A. Merchant Eric F. Howard Vaishali A. Patel Mary K. West Emad Qayed Rosemary Nustas Ali Zakaria Marc S. Piper Jason R. Taylor Lujain Jaza Nauzer Forbes Millie Chau Luis F. Lara Georgios I. Papachristou Michael L. Volk Valerie Durkalski 《Clinical gastroenterology and hepatology》2021,19(7):1355-1365.e4
49.
LeVan TD Von Essen S Romberger DJ Lambert GP Martinez FD Vasquez MM Merchant JA 《American journal of respiratory and critical care medicine》2005,171(7):773-779
RATIONALE AND OBJECTIVES: Farmers experience airway obstruction, which may be attributable in part to endotoxin inhalation. CD14 is a receptor for endotoxin. MATERIALS AND METHODS: Based on our findings of increased circulating CD14 associated with the CD14/-159 T allele, we hypothesized that carriers of this allele would have decreased lung function among endotoxin-exposed individuals. CD14/-159TT farmers (n = 19) had significantly lower lung function as measured by FEV1 (p = 0.028) and mean forced expiratory flow during the middle half of the FVC (FEF25-75) (p = 0.05) compared with farmers with the C allele (n = 78). Also, farmers with the CD14/-1619GG genotype (n =11) were associated with lower lung function (FEV1, p = 0.008; FEF25-75, p = 0.009) compared with farmers with the A allele (n = 86). RESULTS: No association between CD14/-550 and lung function was observed (FEV1, p = 0.32; FEF25-75, p = 0.11). Increased prevalence of wheezing was reported in farmers homozygous for CD14/-159T (p = 0.013) or CD14/-1619G (p = 0.019) compared with farmers with the CC or AA genotype, respectively. No association was found between TLR4/Asp299Gly and lung function or wheeze. CONCLUSION: We conclude that the CD14/-159 or CD14/-1619 loci may play a role in modulating lung function and wheeze among agricultural workers. 相似文献
50.
The objective of this study was to investigate changes in luteal cell cholesterol biosynthetic capacity, cholesterol accumulation, lipoprotein receptor activity, and in vivo steroidogenesis during pregnancy. Cholesterol biosynthetic capacity was assessed by measuring both the activity and the content of the rate-limiting enzyme 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase and by monitoring [14C]acetate incorporation into luteal sterols. The results showed that HMG-CoA reductase activity increased steadily during the first few days of pregnancy and reached a peak value on day 10. Subsequently, enzyme activity dropped precipitously and remained low until parturition. A parallel decline in the rate of conversion of 14C-labeled sterols was observed. Such changes in HMG-CoA reductase activity were not related to the phosphorylation/dephosphorylation state of the enzyme, but were due to a reduction in the amount of enzyme protein, as determined by the immunoblotting technique. Despite the highly active HMG-CoA reductase in the first half of pregnancy, very little cholesterol ester was stored, and serum progesterone concentrations were only about 50-75 ng/ml. However, from midpregnancy, the corpus luteum became capable of storing more cholesterol ester and producing more progesterone at a time when its ability to synthesize cholesterol declined. At this stage, luteal cells appear to shut off de novo synthesis and use principally exogenous cholesterol. To find out whether this is due to an increase in the number of high density lipoprotein (HDL) receptors, HDL-binding activity was determined in luteal cells throughout pregnancy. Whereas the Kd and the number of binding sites per mg protein were similar between days 6-18, the total content of HDL receptor increased markedly with the size of the corpus luteum. In summary, the present investigation indicates that pregnancy profoundly influences the ability of the corpus luteum to acquire, synthesize, and process the cholesterol substrate needed for steroidogenesis. 相似文献