促血管生成素在肝癌组织中的表达与肝癌新生血管形成及转移的关系

目的　观察促血管生成素 (angiopoietin)在肝细胞癌组织中的表达 ,探讨其临床意义。方法　采用原位分子杂交和免疫组织化学染色方法检测两种促血管生成素Angiopoietin 1(Ang 1)、Angiopoietin 2 (Ang 2 )以及血管平滑肌激动蛋白 (α smoothmuscleactin ,α SMA)在正常肝脏组织和肝细胞癌组织中的表达。结果　Ang 1mRNA在正常肝脏和肝癌组织中都有表达 ,肝癌组织和癌旁组织 (5 6± 6 /HP)以及正常肝脏 (6 7± 11/HP)之间差异没有显著意义 (t=3 2 14 ,P =0 12 6 )。Ang 2mRNA在正常肝脏不表达 ,肝癌组织中阳性表达 (阳性细胞数为 32± 8/HP)。Ang 2集中于癌灶边缘、血管周围。肝癌组织中微血管密度 (15± 2 /HP)和新生血管的数量 (9± 3/HP)明显高于正常肝脏(分别为 5± 1/HP和阴性 ) ,Ang 2的表达随肝癌组织的病理学分级、有无转移以及新生血管数和微血管密度而增加 (t=2 714 ,P =0 0 31)。结论　促血管生成素在肝癌的新生血管形成和转移过程中可能起到一定作用。Ang 2可能参与了肝癌的新生血管形成。     

抗血管内皮生长因子抗体对实验性肝癌的生长抑制作用

目的了解抗血管内皮生长因子(VEGF)抗体对人肝癌的生长抑制作用.方法在已建立的人肝癌裸鼠皮下种植瘤的瘤灶旁,注射抗VEGF抗体,观察肿瘤生长情况,用CD31的免疫组化方法检测肿瘤内部的微血管密度(iMVD),用原位末端转移酶标记技术检测凋亡的肿瘤细胞.结果实验结束后1周,实验组和对照组肿瘤大小(长×宽)是(26.46±19.81) mm2和(105.77±17.40) mm2(P<0.001),2周后是(45.20±23.02) mm2和(150.77±77.41) mm2(P<0.05),而此时肿瘤的iMVD是(2 311±120)个/mm2和(3 900±328)个/mm2 (P<0.001); 肿瘤细胞凋亡指数是15.31% 和 6.83%(P<0.005).结论抗VEGF抗体能通过抑制肿瘤微血管的生长,抑制实验性人肝癌的生长,其实质是增加了肿瘤细胞凋亡.     

抗肿瘤血管形成剂抑制肝癌生长及转移的实验研究

目的　研究α干扰素 (IFN α)对肝癌生长及转移的抑制作用及其是否通过抑制一氧化氮合酶 (Ⅱ型 ,iNOS)和血管内皮生长因子 (VEGF)进而减少肝癌血管形成起作用。方法　应用裸鼠人肝癌转移模型LCI D2 0 ,于肿瘤移植后第 2天每只开始皮下注射不同剂量IFN α(3× 10 5U/d ,6×10 5U/d) ,每天 1次 ,对照组注射相同体积的生理盐水。每组治疗 35d后处死部分裸鼠 ,测量移植瘤大小 ,观察肺转移情况 ;剩余裸鼠继续用药观察IFN α对其生存时间的影响。LCI D2 0肿瘤组织移植到裸鼠角膜建立角膜微囊移植模型 ,检测IFN α对肝癌肿瘤血管形成的抑制作用。免疫组织化学方法检测治疗前后肝癌组织iNOS ,VEGF及肿瘤微血管密度变化。结果　对照组裸鼠肺转移率为10 0 % (10 /10 ) ,移植瘤大小为 8475± 2 6 36mm3,生存时间为 45± 4d ;IFN α 3× 10 5U/d治疗组分别为 5 0 % (4/8)、76 9± 2 87mm3 和 81± 6d ,与对照组比较移植瘤大小及生存时间差别有统计学意义 (P<0 0 1) ;而二者之间肺转移率无统计学差别 (P >0 0 5 ) ;IFN α 6× 10 5U/d治疗组则分别为 0 (0 /8)、13± 9mm3 和 10 5± 2 4d ,与对照组比较差别有统计学意义 (P <0 0 1)。应用裸鼠角膜微囊移植模型检测LCI D2 0肝癌组织有较强的诱导肿瘤血管形成的效应     

肝动脉阻断对大鼠肝癌血供与VEGF、MMP表达的影响

目的　观察肝动脉阻断对大鼠移植性肝癌的血液灌流与血管内皮生长因子 (VEGF)、基质金属蛋白酶 1(MMP 1)表达的影响 ,初步探索肝动脉栓塞促进肝癌转移的机制。方法　采用大鼠肝内移植Walker 2 5 6肿瘤模型 ,以肝动脉结扎 (HAL)的方法阻断肝动脉血供 ,模拟肝动脉栓塞治疗。分为对照组、剖腹对照组、HAL组。Hoechst33342标记法检测瘤组织血液灌流 (标记细胞数代表血供情况 ) ,酶联免疫吸附试验 (ELISA)测定血清VEGF水平 ,原位杂交法检测瘤组织VEGF、MMP 1表达。结果　HAL后 2d瘤组织血供明显下降 (对照组每高倍视野Hoechst33342标记细胞数 383 6± 19 2 ,HAL组 32 9 1± 2 9 3 ,P <0 0 1)。血清VEGF水平明显升高 (对照组 5 4 9± 19 3pg ml,HAL组 92 5± 43 9pg ml,P <0 0 5 )。瘤组织VEGF、MMP 1mRNA表达水平较对照组、剖腹对照组明显升高 (P <0 0 5 )。瘤组织血供与血清VEGF水平、瘤组织VEGF表达负相关。结论　肝动脉阻断使癌组织血供减少 ,转移相关基因VEGF、MMP 1表达升高。血供减少、缺氧加重可能为其诱导VEGF表达的主要机制。     

人促血管生成素2单链抗体对裸鼠人肝癌血管生成及肿瘤生长的作用

目的 观察促血管生成素2(Ang2)单链抗体(ScFv-Ang2)对人肝癌血管生成及肿瘤生长的作用.方法 体外培养人脐静脉内皮细胞(HUVEC),各组分别添加血管内皮生长因子(VEGF)、VEGF+ Ang2、VEGF+ Ang2+ ScFv-Ang2,通过HUVEC增殖测定、迁移实验、小管形成实验观察ScFv-Ang2在体外对HUVEC生物学行为的影响;建立荷人肝癌细胞株MHCC97的肝原位移植瘤模型裸小鼠24只,随机分为实验组和对照组,实验组瘤内注射ScFv-Ang2 (4×1011 pfu/ml),对照组予以生理盐水,测量肿瘤大小、肺转移灶数目、癌组织CD31蛋白表达及微血管密度(MVD)计数,观察ScFv-Ang2对肝细胞癌(HCC)血管生成及肿瘤生长的作用.结果 体外实验中观察到ScFv-Ang2可抑制VEGF和Ang2诱导的HUVEC增殖、迁移及小管形成;ScFv-Ang2瘤内注射组肿瘤体积、重量、肺转移灶数目、CD31表达水平以及MVD计数均显著低于对照组(P＜0.05).结论 ScFv-Ang2在体外实验中具有抑制HUVEC形成血管的作用,体内实验中对裸鼠人肝癌具有抑制血管生成和肿瘤生长的作用.     

血管内皮细胞生长因子基因转染血管内皮祖细胞移植提高移植脂肪存活率的实验研究

目的探讨血管内皮细胞生长因子165(VEGF165)基因转染血管内皮祖细胞(EPCs)移植促进游离移植的脂肪组织的血管新生,提高移植脂肪组织存活率。方法体外分离、培养人脐血中EPCs,利用脂质体介导VEGF165基因体外转染EPCs,然后与来自人体的脂肪组织混合移植于裸鼠背部,裸鼠随机分为3组:VEGF165基因转染组、EPCs组及M199培养基对照组。结果脐血中分离培养的EPCs表达CD34、血管内皮细胞生长因子受体及CD133;VEGF165基因转染EPCs体外及体内检测均有VEGF165蛋白的表达。VEGF165基因转染组、EPCs组中,EPCs整合到缺血部位新生血管中,与对照组的脂肪组织存活率分别为(96.2±8.6)%、(75.3±6.8)%和(40.2±2.5)%(P<0.05),VEGF165基因转染组与EPCs组脂肪组织周边区毛细血管密度有显著差异(P<0.05),均高于对照组(P<0.05)。术后3个月时3组脂肪组织周边区的EPCs密度分别为(196±16)个/mm2、(95±11)个/mm2、0个/mm2(P<0.05)。结论脐血中的EPCs体外培养后移植体内可促进游离移植的脂肪组织的血管新生,提高存活率,而转染VEGF165基因的EPCs具有更强的促血管新生的作用。     

鼠源性血管抑素对裸鼠种植性肿瘤的抑制作用

目的　探讨鼠源性血管抑素转染入人肝癌细胞SMMC 772 1后对裸鼠种植性肿瘤的影响。　方法　建立鼠源性血管抑素基因的人肝癌SMMC 772 1细胞株 ,实验动物分 3组 :空白对照组种植SMMC 772 1细胞 ,空载体组种植SMMC 772 1/pcDNA3 1(+)细胞 ,血管抑素组种植SMMC 772 1/pcDNA3 1 mAST细胞。比较各组裸鼠肿瘤体积、重量和肿瘤微血管密度 (MVD)。　结果　在肿瘤细胞种植 35d时裸鼠肿瘤体积 :空白对照组 (35 38 1± 6 43 3)mm3 ,空载体组 (312 8 5± 5 46 6 )mm3 ,血管抑素组 (75 5 8± 198 2 )mm3 ;肿瘤重量 :空白对照组 (6 0± 0 7)g,空载体组 (5 9± 0 5 )g ,血管抑素组(2 1± 0 5 )g;肿瘤MVD :空白对照组 5 2 2± 6 6 ,空载体组 49 4± 7 0 ,血管抑素组 2 5 5± 4 1。血管抑素组裸鼠肿瘤体积、重量和MVD显著小于空白对照组和空载体组 (P均 <0 0 1) ,肿瘤的抑制率达78 6 %。　结论　转染血管抑素基因的人肝癌细胞SMMC 772 1在裸鼠体内的致瘤力明显降低 ,肿瘤的体积、重量和微血管密度显著低于对照组 ,表明血管抑素可通过抑制肿瘤血管生成而显著抑制肿瘤生长     

Genistein抑制裸鼠肝癌移植瘤侵袭性生长

目的　研究Genistein对裸鼠肾包膜下肝癌移植瘤侵袭性生长的作用及其作用机制。方法　10只裸小鼠分成2 组,每只裸小鼠均建立双侧肾包膜下肝癌移植瘤模型,予Genistein(5 mg/ml)腹腔内注射,共15 d。观察移植瘤生长及对肾实质侵袭能力变化,行肿瘤微血管密度(MVD)的免疫组化检测及MMP2与TIMP2表达的RT PCR检测。结果　Genistein治疗组瘤体积增加(63 .32±8. 96) mm3,显著小于对照组(79 .25±6. 85) mm3,P<0 .05,抑瘤率为20 1%;MVD在Genistein组(10 .422±0 .807)显著低于对照组(22 330±5 696),P<0. 05。MMP2 表达在Genistein组(0 .296±0. 132)显著低于对照组(0. 519±0 .158),P<0 .05;TIMP2 表达两组间并无显著差异,但MMP2/TIMP2比值在Genistein组(0. 498±0.214)显著低于对照组(1 .011±0. 319),P<0 .05。结论　Genistein显著抑制Bel 7402肝癌移植瘤在裸小鼠肾包膜下的侵袭性生长,病理性肿瘤血管生成减少及MMP2表达降低与其抗肿瘤侵袭作用密切相关。     

白细胞介素-12基因再修饰基因瘤苗免疫小鼠的脾细胞过继治疗肝癌

目的　探讨白细胞介素 (IL) 2和B7 1双免疫基因转染肝癌细胞瘤苗免疫小鼠后获得的脾淋巴细胞经mIL 12基因修饰后治疗小鼠肝癌的可行性和疗效。方法　用 2 0 0PFU 细胞滴度的重组腺病毒载体 (Adv)将人IL 2和B7 1基因共同转染小鼠肝癌Hepal 6细胞株 ,经 80mg L丝裂霉素 (MMC)处理制备成肝癌细胞瘤苗 ,免疫同系小鼠后分离其脾淋巴细胞 (SLC) ,转染mIL 12基因 (Adv滴度 2 0 0PFU 细胞 )后注射入直径 1cm的小鼠皮下移植肝癌内 ,观察抗瘤效果。结果　转mIL 12基因SLC治疗组小鼠瘤体增加值最小 ( 0 .0 8± 0 .0 5 )cm3,与各对照组比差异有显著性 [(转染BGFP基因SLC、未转染SLC和生理盐水注射组分别为 ( 3 .46± 0 .15 ) ,( 3 .5 6± 0 .2 3)和( 8.12± 0 .5 4)cm3,P <0 .0 5 ]。结论　IL 2和B7 1双基因修饰肝癌瘤苗诱导小鼠产生的免疫脾淋巴细胞可能成为一种新的过继免疫治疗效应细胞及携带IL 12基因的载体细胞 ;基因治疗、特异性主动免疫和过继性细胞免疫治疗结合将有更优越的抗瘤效果。     

酪丝缬肽对人肝癌裸鼠移植瘤的抗血管生成作用及其机制

目的 探讨三肽化合物酪丝缬肽(YSV)对人肝癌细胞SMMC-7721裸鼠移植瘤的抑制作用及其抗血管生成机制.方法 建立人肝癌SMMC-7721裸鼠移植瘤模型,免疫组织化学法观察YSV对肿瘤组织中微血管密度(MVD)的影响;应用血管生成相关基因芯片分析YSV对肿瘤组织血管生成相关基因的影响;应用逆转录-聚合酶链反应(RT-PCR)验证相关基因的表达情况,最后酶联免疫吸附试验(ELISA)法测定血清中目的因子的含量.结果 YSV能显著抑制人肝癌SMMC-7721裸鼠移植瘤的生长,当给药剂量为320μg/kg·d~(-1)时效果最为显著,抑瘤率为60.66%.免疫组织化学法证实YSV能够降低肿瘤组织中微血管密度,YSV作用组MVD平均值36.0±11.6,对照组平均值为114.5±26.5.与生理盐水组比较,在113个候选基因中有18个基因下调2倍以上,其中血管内皮生长因子(VEGF)与白细胞介素(IL)-8基因下调最显著;RT-PCR法证实YSV能够抑制肿瘤组织中VEGF与IL-8在mRNA水平上的表达;ELISA亦证明YSV作用组血浆中因子VEGF及IL-8浓度降低.结论 YSV能显著抑制人肝癌SMMC-7721裸鼠移植瘤生长,通过抑制肿瘤组织中促血管生成因子的表达来发挥抗肿瘤活性.     

Histochemical and contractile properties of striated muscles of urethra and levator ani of dogs and sheep

AIMS: To understand their possible importance in long- and short-term control of continence, some properties of the striated muscles of the urethra and pelvic floor (levator ani) of dogs and sheep were investigated, especially fiber types and contractile characteristics. MATERIALS AND METHODS: Striated muscles of urethra and levator ani of 29 male and 6 female dogs and 11 male and 6 female sheep were removed and cut into strips. Some strips were frozen and stained for ATPase at pH 9.4 and 4.3 for fiber typing; others were set up in an organ bath to study contractile responses to nerve stimulation. RESULTS: All muscles contained both type I (slow) and type II fibers, ranging from 97% type II in female greyhound urethra to 60% in female sheep levator ani. For each muscle, there were fewer type II muscles in sheep than in dog. The diameters of the urethral fibers were about 60% of the levator ani in dogs and 34% in sheep. Contraction of the urethral muscle was faster than for levator ani and declined to about 80% of the peak, 500 msec after the beginning of stimulation at 20 Hz. The levator ani contraction rose to a steady level as long as stimulation continued. CONCLUSIONS: Both the levator ani and urethral striated muscles contain slow and fast fiber types. The levator ani muscles are capable of sustained contraction with rapid onset which will produce long-term closure of the urethra. The circular urethral muscle contraction was faster but less well maintained.     

Recognition and management of phaeochromocytoma and paraganglioma

Phaeochromocytomas and paragangliomas (PPGL) are catecholamine-secreting neuroendocrine tumours arising from the chromaffin cells in the adrenal medulla. These tumours may be identified incidentally, as part of a work-up for multiple endocrine neoplasia or following haemodynamic surges during unrelated procedures. Advances in perioperative management and improved management of intraoperative haemodynamic instability have significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection where possible is associated with improved outcomes. Anaesthetic management of PPGL cases represents a unique haemodynamic challenge both before and after tumour resection. In this article we describe the physiology of these tumours, their diagnosis, preoperative optimization methods, intraoperative anaesthetic management and management of postoperative complications.     

Instrumented ligamentotaxis and stabilization of compression and burst fractures of dorsolumbar and mid-lumbar spines

Background:

Controversy continues regarding the best treatment for compression and burst fractures. The axial distraction reduction utilizing the technique employing the long straight rod or curved short rod without derotation to reduce fracture are practised together with short segment posterolateral fusion (PLF). Effects of the early postoperative mobilization without posterolateral fusion on reduction maintenance and fracture consolidation were not evaluated so far. The present prospective study is designed to assess the effectiveness of i) reduction and restoration of sagittal alignment, ii) no posterolateral fusion on the reduced, fractured vertebral body and injured disc, iii) fracture consolidation and iv) the fate of the unfused cephalad and caudal injured motion segments of the fractured vertebra.

Materials and Methods:

The study includes 15 Denis burst and two Denis type D compression fractures between T₁₂ and L₃. The lordotic distraction technique was used for ligamentotaxis utilizing the contoured short rods and pedicle screw fixator. Three vertebrae including the fractured one were fixed. The patients after surgery were braced for ten weeks with activity restriction for 2-4 weeks. The patients were evaluated for change in vertebral body height, sagittal curve, reduction of retropulsion, improvement in neural deficit. The unfused motion segments, residual postoperative pain and bone and metal failure were also evaluated.

Results:

The preoperative and postreduction percentile vertebral heights at, zero (immediate postoperative), at three, six and 12 months followup were 62.4, 94.8, 94.6, 94.5 and 94.5%, respectively. The percentages of the intracanal fragment retropulsion at preoperative, and postoperative at zero, 3, 6 and 12 months followup were 59.0, 36.2,, 36.0, 32.3, and 13.6% respectively.The preoperative and postreduction percentile loss of the canal dimension and at zero, three, six and 12 months were 52.1, 45.0, 44.0, 41.0 and 29% respectively suggesting that the under-reduced fragment was being resorbed gradually by a remodeling process. The mean initial kyphosis of 33° became mean 2° immediately after reduction and mean 3° at the final followup. The fractured vertebral bodies consolidated in an average period of ten weeks (range 8-14 weeks). The restored disc heights were relatively well maintained throughout the observation period. All paraparetic patients recovered neurologically. There were no postoperative complications.

Conclusion:

Instrument-aided ligamentotaxis for compression and burst fractures utilizing the short contoured rod derotation technique and the instrumented stabilization of the fractured spine are found to be effective procedures which contribute to the fractured vertebral body consolidation without recollapse and maintain the motion segment function.     

Incorporation and release of85Sr and14C-proline-hydroxyproline in mineral and collagen of bone and incisor teeth of growing rats

The extent to which exchange and reutilization processes of mineral tracers affect skeletal mineral accretion and resorption measurements was evaluated by comparing the rates of appearance and disappearance of⁸⁵Sr and¹⁴C-proline-hydroxyproline in bones and teeth in growing rats for 12 days following simultaneous parenteral injection of these tracers. Expressions for the relative rates of collagen synthesis and breakdown, which unlike mineral metabolism are considered not to be complicated by exchange phenomena, were based on¹⁴C-proline conversion to¹⁴C-hydroxyproline; the specific activity of the latter was determined. Both the mineral and the collagen specific activities reflected the rates and patterns of growth of the samples assayed; rapid growth and a short interval of time between formation and resorption of tissue in themetaphyseal bone which contains the cartilagineous growth plate, slow growth and an interval of time between formation and resorption of tissue indiaphyseal bone and incisor teeth which is longer than the 12 days of the experiment. However, in metaphyseal bone the specific activity collagen/mineral ratio dropped by one half during the 4–12 day interval in contrast to diaphyseal bone and incisor teeth in which no change in this ratio was observed during this period of time. The data indicate that collagen in the metaphyseal growth zone is removed by resorption before it has become fully mineralized, and that exchange is a relatively unimportant factor in the long term kinetics of bone mineral.

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Zusammenfassung Das Ausmaß, bis zu welchem Austausch- und Wiederverwendungsprozesse der mineralen Tracer die Messungen des mineralen Skelett-Auf- und Abbaues beeinflussen können, wurde ausgewertet; zu diesem Zweck wurde die Geschwindigkeit des Auftretens und Verschwindens von⁸⁵Sr und von¹⁴C-Prolin-Hydroxyprolin in Knochen und Zähnen von wachsenden Ratten während der 12 auf die simultane parenterale Injektion dieser Tracer folgenden Tage verglichen.Der Ausdruck für die relative Geschwindigkeit des Kollagen-Auf- und Abbaues, bei welchem im Gegensatz zum Mineralmetabolismus kein Mitwirken des Austauschphänomens vermutet wird, basiert auf der Umwandlung von¹⁴C-Prolin zu¹⁴C-Hydroxyprolin; die spezifische Aktivität des letzteren wurde bestimmt.Aus der spezifischen Aktivität des Minerals sowie jener des Kollagens konnten die Geschwindigkeit und die Art des Wachstums der untersuchten Proben ersehen werden, d.h.schnelles Wachstum und ein kurzes Zeitintervall zwischen Bildung und Resorption des Gewebes imKnochen der Metaphyse, die auch die knorpelige Wachstumsplatte enthält, und andererseitslangsames Wachstum und längeres Zeitintervall (länger als die 12 Tage des Experimentes) zwischen Bildung und Resorption des Gewebes imKnochen der Diaphyse und in den Schneidezähnen. Immerhin fiel die spezifische Aktivität des Kollagen/Mineral-Anteils im Knochen der Metaphyse während dem 4–12tägigen Zeitintervall auf die Hälfte, im Gegensatz zum Knochen der Diaphyse und der Schneidezähne, bei welchen während dieser Zeitspanne kein Unterschied in diesem Verhältnis beobachtet wurde.Diese Ergebnisse zeigen, daß Kollagen in der Wachstumszone der Metaphyse durch Resorption verschwindet, bevor es ganz mineralisiert ist, und daß der Austausch ein relativ unwichtiger Faktor in der Kinetik auf lange Sicht des Knochenminerals ist.

     

Physiology and pharmacology of nausea and vomiting

Nausea and vomiting are both very unpleasant experiences. The physiology is poorly understood; however, understanding what we do know is key to tailoring a preventative or therapeutic antiemetic regime. There are two key sites in the central nervous system implicated in the organization of the vomiting reflex: the vomiting centre and the chemoreceptor trigger zone. There are five key neurotransmitters involved in afferent feedback to these areas. These are histamine (H₁ receptors), dopamine (D₂), serotonin (5-HT₃), acetyl choline (muscarinic) and neurokinin (substance P). Postoperative nausea and vomiting will occur in around one-third of elective patients who have no prophylaxis. This can result in many detrimental effects including patient dissatisfaction, unplanned admission and prolonged recovery. It is therefore essential that clinicians understand how they can prevent and treat nausea and vomiting using either a single agent or a combination of antiemetics to target relevant receptors. Commonly used drugs include antihistamines, dopamine antagonists, serotonin antagonists and steroids. More novel agents are being developed such as aprepitant, a neurokinin receptor antagonist, palonosetron, a 5HT₃ receptor antagonist and nabilone, a synthetic cannabinoid.     

Physiology and pharmacology of nausea and vomiting

Nausea and vomiting are both very unpleasant experiences. The physiology is poorly understood; however, understanding what we do know is key to tailoring a preventative or therapeutic antiemetic regime. There are two key sites in the central nervous system implicated in the organization of the vomiting reflex: the vomiting centre and the chemoreceptor trigger zone. There are five key neurotransmitters involved in afferent feedback to these areas. These are histamine (H₁ receptors), dopamine (D₂), serotonin (5-HT₃), acetyl choline (muscarinic) and neurokinin (substance P). Postoperative nausea and vomiting will occur in around one-third of elective patients who have no prophylaxis. This can result in many detrimental effects including patient dissatisfaction, unplanned admission and prolonged recovery. It is therefore essential that clinicians understand how they can prevent and treat nausea and vomiting using either a single agent or a combination of antiemetics to target relevant receptors. Commonly used drugs include antihistamines, dopamine antagonists, serotonin antagonists and steroids. More novel agents are being developed such as aprepitant, a neurokinin receptor antagonist, palonosetron, a 5HT₃ receptor antagonist, and nabilone, a synthetic cannabinoid.     

动静脉穿刺网络课件的开发及其应用

目的:确保护理教学效果,提高教学水平。方法:应用多项信息技术将动静脉穿刺技术制作成教学网络课件,并用于临床教学。结果:该课件在本校园网上运行半年余,2000余人次对其进行访问,受到师生好评。结论:该课件能及时反映动静脉穿刺的最新研究进展及具体操作步骤和使用方法,实现护理教学的直观性和交互性,对护理教学和临床带教指导有一定的借鉴作用。     

Physiology and pharmacology of nausea and vomiting

The physiology of nausea and vomiting is poorly understood. The initiation of vomiting varies and may be due to motion, pregnancy, chemotherapy, gastric irritation or postoperative causes. Once initiated, vomiting occurs in two stages, retching and expulsion. The muscles responsible for this sequence of events are controlled by either a vomiting centre or a central pattern generator, probably in the area postrema and the nearby nucleus tractus solitarius. Drugs which induce vomiting include ipecacuanha, a gastric irritant, and apomorphine, a dopamine-receptor agonist. Opioid drugs also induce vomiting, but opioid antagonists are not useful to treat nausea and vomiting. Anti-emetic drugs consist of a variety of neurotransmitter antagonists and may act in the periphery, the central nervous system or both sites. The most important drugs are antagonists at muscarinic, dopamine D₂, 5-HT₃, histamine H₁ and neurokinin NK₁ receptors. These drugs are discussed with particular attention to post-operative nausea and vomiting (PONV).