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1.
J B Martin J F Annegers J D Curb S Heyden C Howson E S Lee M Lee 《Preventive medicine》1988,17(3):310-320
The effect of caffeine consumption on mortality was evaluated in a historical cohort study of 10,064 diagnosed hypertensive individuals participating in the Hypertension Detection and Follow-up Program from 1973 to 1979. Total caffeine intake level from beverages (coffee and tea) and certain medications, was estimated at the 1-year visit. No evidence was found supporting an association between increased level of caffeine consumption and increased all-cause mortality or cardiovascular disease mortality during the following 4 years. Cigarette smoking was significantly associated with mortality; the association being more pronounced among non- and low-caffeine consumers for all-cause mortality and among non-caffeine consumers for all cardiovascular mortality except cerebrovascular mortality. 相似文献
2.
^125I放射微粒微创植入治疗前列腺癌 总被引:1,自引:0,他引:1
目的观察^125I放射微粒植入对前列腺癌的治疗效果。方法对26例临床确诊为前列腺癌患者经皮穿刺在癌组织植入^125I放射微粒,每例平均36粒,术后复查肛诊、B超、影像学及血生化指标。结果患者植入治疗经过顺利,2例少量出血,留置导尿后愈合,3个月后经肛诊、直肠B超示结节缩小,前列腺特异性抗原(PSA)降低,多普勒超声显示结节内动脉收缩期最大血流速度(VS)、阻力指数(RI)及动脉搏动指数(PI)均明显下降。结论^125I放射微粒植入对前列腺癌的治疗安全性好、效果可靠。 相似文献
3.
We have used three-dimensional reconstructions from serial sections as well as cleared and stained specimens to infer patterning of the pharyngeal dentition throughout ontogeny in the zebrafish. Each pharyngeal tooth has been monitored from its initiation to its complete disappearance (resorption and shedding). We have identified tooth families and have studied the persistence of the pattern through successive replacements. Teeth arise in two seemingly independent clusters, a ventral and a dorsal cluster, with differing patterning features. The ventral cluster consists of one row of five teeth in which a tooth is first initiated in position four, and subsequent teeth in adjacent positions, posterior and anterior to it. Replacement teeth in odd and even positions are initiated simultaneously during successive odontogenic waves but differ in generation number according to the timing of appearance of the first-generation tooth, i.e., the founder of the tooth family. Up to four teeth of a single tooth family are simultaneously present in early juveniles of which two are usually "co-functional." The number of teeth per tooth family is reduced in older juveniles and adults, reflecting a slowing down of the replacement rate. The consistent way in which the pattern is established and maintained during ontogeny calls for research of the presence of specific molecular controls. 相似文献
4.
Teun P De Boer Bart Kok Kirsten I E Neuteboom Nicole Spieker Jochum De Graaf Olivier H J Destrée Martin B Rook Toon A B Van Veen Habo J Jongsma Marc A Vos Jacques M T De Bakker Marcel A G Van Der Heyden 《Developmental dynamics》2005,233(3):864-871
Connexin-containing gap junctions play an essential role in vertebrate development. More than 20 connexin isoforms have been identified in mammals. However, the number identified in Xenopus trails with only six isoforms described. Here, identification of a new connexin isoform from Xenopus laevis is described. Connexin40.4 was found by screening expressed sequence tag databases and carrying out polymerase chain reaction on genomic DNA. This new connexin has limited amino acid identity with mammalian (<50%) connexins, but conservation is higher (approximately 62%) with fish. During Xenopus laevis development, connexin40.4 was first expressed after the mid-blastula transition. There was prominent expression in the presomitic paraxial mesoderm and later in the developing somites. In adult frogs, expression was detected in kidney and stomach as well as in brain, heart, and skeletal muscle. Ectopic expression of connexin40.4 in HEK293 cells, resulted in formation of gap junction like structures at the cell interfaces. Similar ectopic expression in neural N2A cells resulted in functional electrical coupling, displaying mild, asymmetric voltage dependence. We thus cloned a novel connexin from Xenopus laevis, strongly expressed in developing somites, with no apparent orthologue in mammals. 相似文献
5.
E. P. Rieber H. W. v. Heyden R. P. Linke J. G. Saal G. Riethmüller H. D. Waller 《Journal of molecular medicine (Berlin, Germany)》1976,54(21):1011-1019
Zusammenfassung Bei vier Patienten mit Haarzell-Leukämie wurden die leukämischen Zellen auf das Vorkommen von Oberflächenimmunglobulinen und Fc-Rezeptoren sowie die Stimulierbarkeit mit verschiedenen Mitogenen hin untersucht. Die Analyse dieser Eigenschaften erfolgte mit Hilfe einer kombinierten zytochemisch-radioautographischen Technik, bei der die radioaktiv markierten Zellen durch den Nachweis des Tartrat-resistenten Isoenzyms der sauren Phosphatase als Haarzellen identifiziert werden konnten. Für den Nachweis der Oberflächenimmunglobuline wurden125I-markierte (Fab')2-Fragmente von monospezifischen Antikörpern gegen schwere Immunoglobulinketten verwendet. Bei zwei Patienten wurden auf der Oberfläche der isoenzymhaltigen Zellen - und -Immunglobulinketten nachgewiesen, die bei einem großen Teil dieser Zellen gleichzeitig auf der Zelloberfläche ausgedrückt waren. Bei einem Patienten zeigten die isoenzymhaltigen Zellen - und -Ketten und bei einem vierten Patienten nur -Ketten. Bei einer Patientin konnten - und -Ketten nach einer in vitro-Kultur von 14 Tagen in Humanserum-freiem Medium in gleicher Weise nachgewiesen werden wie auf frischen Zellen, was für eine Synthese der Oberflächenimmunglobuline durch die Haarzellen selbst spricht. In der indirekten Immunfluoreszenztechnik wurden die Oberflächenimmunglobuline sehr schnell über einem Zellareal konzentriert, in dem auch Latexpartikel nach der Phagozytose lokalisiert waren. Mit Hilfe von125I-markierten Aggregaten von humanem IgG konnten bei allen vier Patienten Fc-Rezeptoren auf fast 100% der isoenzymhaltigen Zellen nachgewiesen werden. Eine deutliche, wenn auch geringe Stimulation der isoenzymhaltigen Zellen konnte beobachtet werden, wenn die Haarzellen mit Pokeweed-Mitogen oder Lima-Bohnen-Lektin (B- und T-Zell-Mitogene) kultiviert wurden, nicht jedoch, wenn die Stimulation mit Phytohämagglutinin oder Concanavalin-A (T-Zell-Mitogene) erfolgte. Bei keinem der drei untersuchten Patienten bildeten die Haarzellen Spontanrosetten mit Schaferythrozyten.Die Arbeit wurde von der Deutschen Forschungsgemenschaft im Rahmen der Forschergruppe biochemische und immunologische Grundlagen der Leukämie- und Tumortherapie unterstützt 相似文献
6.
Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care 相似文献
7.
Endourological surgical procedures (transurethral resection and fulguration, Nd-YAG-laser application) for the treatment of interstitial cystitis (IC) have been evaluated only in a few studies. Theoretically, they could be the next step in a therapeutic concept after conservative measures have failed and before open surgery is performed as an ultima ratio. However, our review of the literature suggests that to date there is no scientific evidence to support endourological techniques in the treatment of IC. 相似文献
8.
L-type Ca(2+) channels are predominantly regulated by beta-adrenergic stimulation, enhancing L-type Ca(2+) current by increasing the mean channel open time and/or the opening probability of functional Ca(2+) channels. Stimulation of beta-adrenergic receptors (ARs) results in an increased cyclic adenosine monophosphate (cAMP) production by adenylate cyclase (AC) and consequently activation of protein kinase (PK) A and phosphorylation of L-type Ca(2+) channels by this enzyme. Beta(1)-Adrenergic receptors couple exclusively to the G protein Gs, producing a widespread increase in cAMP levels in the cell, whereas beta(2)-adrenergic receptors couple to both Gs and Gi, producing a more localized activation of L-type Ca(2+) channels. Other signaling intermediates (protein kinase C, protein kinase G or protein tyrosine kinase (PTK)) either have negative effects on L-type Ca(2+) current, or they interact with the stimulatory effect of the protein kinase A pathway. 相似文献
9.
目的探讨显微镜辅助下颈前路椎间盘切除植骨融合术(anterior cervical discectomy with fusion,ACDF)治疗多节段脊髓型颈椎病的疗效。方法回顾性分析2011年1月~2012年8月本院行颈前路手术治疗的60例脊髓型颈椎病患者的临床资料,根据手术方式分为常规ACDF组(A组,30例)和显微镜辅助ACDF组(B组,30例)。比较2组的手术时间、术中出血量、住院天数及并发症,以日本骨科学会(Japanese Orthopaedic Association,JOA)评分(17分法)及其改善率评价术后神经功能改善情况。结果 A组手术时间为(132.5±8.9)min,B组为(137.0±9.1)min,差异无统计学意义(P0.05)。A组术中出血量为(113.6±8.0)m L,B组为(93.7±5.3)m L,差异有统计学意义(P0.01)。A组住院(7.37±1.73)d,B组(6.63±1.13)d,差异无统计学意义(P0.05)。A组术前JOA评分为6.60±1.21,术后12个月为13.83±0.91,改善率为(69.72±7.66)%;B组术前JOA评分为6.87±1.46,术后12个月为14.23±1.17,改善率为(72.51±11.26)%。A组和B组改善率差异有统计学意义(P0.05)。结论显微镜辅助ACDF和常规ACDF是治疗多节段脊髓型颈椎病有效的方法,但显微镜辅助ACDF可减少术中出血量,是治疗多节段脊髓型颈椎病优先选择的手术方案。 相似文献
10.