恶性胆管梗阻性病变的MRI及MRCP表现

目的:探讨磁共振MR I及磁共振胰胆管成像MRCP在诊断肝内外恶性胆管阻塞性病变中的价值。方法:收集15例经手术病理和临床治疗证实的胆管恶性肿瘤病例,回顾性分析其影像学表现及与临床病理的关系。MR I检查采用T1W I和T2W I常规序列,所有病例均做MRCP扫描。结果:15例患者MR I均表现为肝内外胆管不同程度阻塞性扩张。阻塞性病变中,胆管腺癌9例,肝细胞癌4例,转移瘤2例。阻塞部位在肝门部7例,胰腺部2例,壶腹部及十二指肠乳头部6例。所有病例均经临床病理证实。结论:MR I与MRCP结合能显示胆管阻塞性扩张及阻塞部位,有较高的诊断价值。壶腹部胆管癌的直接肿块征像较少,以间接阻塞征像为主要诊断依据。     

The cavernoso-anal reflex： response of the anal sphincters to cavernosus muscles＇ stimulation

Aim： To prove the hypothesis that cavernosus muscles＇ contraction during coitus affects the reflex contraction of anal sphincters. Methods： Electromyographic response of external and internal anal sphincters to ischiocavernosus and bulbocavernosus muscle stimulation was studied in 17 healthy volunteers （10 men, 7 women, mean aged 38.3 ± 11.6 years）. The test was repeated after individual anesthetization of anal sphincters and the two cavernosus muscles,and after using saline instead of lidocaine. Results： Upon stimulation of each of the two cavernosus muscles,external and internal anal sphincters recorded increased electromyographic activity. Anal sphincters did not respond to stimulation of the anesthetized cavernosus muscles nor did anesthetized anal sphincters respond to cavernosus muscles＇ stimulation. Saline infiltration did not affect anal sphincteric response to cavernosal muscles＇ stimulation.Conclusion： Cavernosus muscles＇ contraction is suggested to evoke anal sphincteric contraction, which seems to be a reflex and mediated through the ＂cavernoso-anal reflex＂. Anal sphincteric contraction during coitus presumably acts to close the anal canal to thwart flatus or fecal leak.     

The Effect of Esophageal and Gastric Distension on the Crural Diaphragm

Background The mechanism of prevention of gastric reflux into the esophagus is not exactly known. The lower esophagus has a barrier function provided by the lower esophageal sphincter. We investigated the hypothesis that the crural diaphragm shares in the barrier function not only mechanically but also actively through a crural–esophageal–gastric reflex action. Methods The study was performed during repair of abdominal ventral and incisional hernias in 20 subjects (11 men, 9 women; age 38.6 ± 4.8 years). The electromyographic response of the crural diaphragm to individual balloon distension of esophagus and stomach was recorded by means of a needle electrode inserted into the crural diaphragm and connected to an electromyographic apparatus. The recordings were repeated after separate crural, esophageal, and gastric anesthetization. Results The crural diaphragm exhibited basal motor unit action potentials, which decreased on esophageal distension (P < 0.001) after a mean latency of 17.3 ± 2.8 SD ms. The crural diaphragm response to esophageal distension did not occur after the crural diaphragm or esophagus was anesthetized. Gastric distension effected an increase of crural diaphragm electromyographic activity with a mean latency of 18.4 ± 4.6 ms; this effect could not be achieved after the crural diaphragm or stomach was anesthetized. Conclusions The crural diaphragm has a resting tone that relaxes after esophageal distension and contracts after gastric distension. This sphincter-like action of the crural diaphragm appears to be a reflex and is mediated through the esophagocrural inhibitory and gastrocrural excitatory reflexes. The crural diaphragm seems to share actively in the gastroesophageal competence mechanism.     

Effect of warming on the rectal motile activity: identification of rectal warming reflex

BACKGROUND: The identification in the rectal wall of warm receptors sensitive to warm temperature has not been found in the literature. Therefore, we investigated the hypothesis that rectal warming effects rectal dilation, which seems to indicate the existence of warm receptors. MATERIALS AND METHODS: The rectal wall tone was studied in 24 healthy volunteers (14 men, 10 women, mean age 36.7+/-10.4 years). It was assessed by a barostat system during rectal infusion with normal saline at 30 degrees C, 40 degrees C, 45 degrees C, and 50 degrees C. The test was repeated after rectal anesthetization with lidocaine. RESULTS: The rectal tone on rectal saline infusion at a temperature of 30 degrees C showed no response (P>0.05), whereas at a temperature of 40 degrees C, 45 degrees C, and 50 degrees C, it exhibited a significant decrease (P<0.05, <0.01, <0.001, respectively), which was proportional to the rising degree of temperature. Warm saline infusion into the anesthetized rectum resulted in no significant change in the rectal wall tone. CONCLUSIONS: Rectal infusion with warm saline produced rectal dilation that increased with temperature elevation. This effect is suggested to be mediated through a reflex called "rectal warming reflex: and advances the possibility of the existence of warm receptors in the rectal wall; however, further studies are needed to confirm the issue.     

Cavernosus muscle contraction during erection: is it voluntary or reflex, given the striated nature of the muscles?

The bulbo- and ischio-cavernosus muscles (BCM, ICM) contract in the rigid erection phase, leading to a suprasystolic cavernosal pressure. We investigated the hypothesis that the contraction of cavernosal muscles is reflexogenic despite their striated nature. The intracavernosal pressure (ICP) and the cavernosus muscles' electromyography (EMG) were recorded in 18 healthy volunteers in the flaccid and erectile phases. The test was repeated after separate anesthetization of the cavernosus muscles and the corpora cavernosa while the penis was in the rigid erection phase. The ICM and BCM showed no EMG activity with tumescence and full erection. When the ICP reached a mean of 148.6 +/- 9.4 cm H2O, both the ICM and BCM showed increased EMG activity. The suprasystolic pressure was intermittent and corresponded to the intermittent BCM and ICM contraction. Voluntary cavernosus muscle contraction did not increase the ICP at the different stages of erection. Anesthetization of the penis in the rigid erection phase led to disappearance of the cavernosus muscles' EMG activity, while bland gel application did not. Anesthetization of the 2 contracting cavernosus muscles, while the penis was in the rigid phase, produced an ICP drop to 69.5 +/- 7.6 cm H2O; repetition with saline did not affect the ICP. Cavernosus muscle contraction on corporal pressure elevation seems to be reflex and mediated through the corporo-cavernosal reflex (CCR). Changes in the evoked response amplitude would indicate a defect in the reflex pathway.     

TGF-α、TGF-β1及TGFR2在直肠癌中的表达及其临床意义

目的：研究TGF－α、TGF-β1及TGFR2表达与直肠癌生物学行为与预后的关系，并同时观察肿瘤的生物学行为。方法：应用免疫组织化学方法检测TGF－α、TGF-β1及TGFR2在直肠癌患者肿瘤组织的表达情况。结果：TGF－α、TGF-β1及TGFR2的阳性率分别为51．3％、46．2％和41．0％。原发灶中TGF-α的表达随癌组织浸润肠壁深度呈升高趋势，且差异显著（P＜0．05）。有远处转移者TGF－α表达显著高于无远处转移者（P＜0．05）。TGF－α表达水平随Dukes' A-D分期而呈显著升高（P＜0．05）。而TGF－β1及TGFR2表达则完全与TGF－α的情况相反。结论：刺激因子TGF－α的表达增加，抑制因子TGF－β1及其受体TGFR2表达的减少共同加速直肠癌肿瘤细胞的增殖、浸润和转移。     

OCULAR INVOLVEMENT IN THE ACQUIRED IMMUNE DEFICIENCY SYNDROME (AIDS)

The acquired immune deficiency syndrome (AIDS) has reached epidemic proportions in the USA and the incidence of this potentially fatal viral infection is increasing rapidly in Australia. The loss of normal cellular immunity in affected individuals predisposes them to severe opportunistic infections and neoplasms, especially Kaposi's sarcoma. Both of these pathological processes may affect the eye, and ocular involvement with an opportunistic infection or malignancy may be the first clue to the presence of AIDS. We present here the first Australian report of a patient with AIDS presenting with ocular involvement. The case is discussed in relation to current concepts of AIDS.     

葛根素注射液的不良反应及预防

对近年国内文献报道的葛根素注射液不良反应归纳分析。本品可致多系统（如：免疫、血液、泌尿、消化、心血管等系统）不良反应,甚至死亡。因此,应严格按药品说明书合理用药,加强用药监护,预防不良反应的发生。     

RhoA-Rock信号通路抑制剂对缺氧人肺微血管内皮细胞丝状肌动蛋白细胞骨架的影响

目的 用RhoA-Rock信号通路抑制剂探讨肺出血时肺微血管内皮细胞的调控因素.方法 人肺微血管内皮细胞常规培养,分为4组:对照组、抑制剂组、缺氧组和抑制剂缺氧组.异硫氰酸荧光素-鬼笔环肽与胞浆内丝状肌动蛋白(filamentous actin,F-actin)结合而发出红色荧光,共聚焦显微镜扫描观察F-actin的变化情况并记录相应荧光值.结果 细胞缺氧组1h、12 h和24h的F-actin平均荧光强度分别为对照组的(64.3±5.5)％、(60.3±4.2)％和(47.8±4.6)％;抑制剂缺氧组1h、12 h和24h分别为对照组的(66.2±3.2)％、(67.1±6.2)％和(72.5±6.1)％.细胞缺氧组缺氧1h后,F-actin平均荧光强度降低[(64.3±5.5)％],与对照组比较差异有统计学意义(P＜0.05),至缺氧24h,F-actin含量已下降至对照组的(47.8±4.6)％,差异有统计学意义(P＜0.05).抑制剂缺氧组缺氧1h后,F-actin平均荧光强度较缺氧组1h有所升高,为对照组的(66.2±3.2)％,抑制剂组缺氧24h后F-actin平均荧光强度为对照组的(72.5±6.1)％,与缺氧组缺氧24h相比差异有统计学意义(P＜0.05).而抑制剂组不经缺氧的F-actin平均荧光强度与对照组相比无显著变化(P＞0.05).缺氧后细胞皮质状结构消失,应力纤维排列紊乱,随着缺氧时间的延长,F-actin逐渐解聚断裂.用RhoA-Rock信号通路抑制剂预处理细胞后再缺氧,核周围F-actin所形成的皮质状结构重新出现,细胞浆内应力纤维的排列和分布趋向于规律,F-actin断裂减少.结论 RhoA-Rock信号通路在肺微血管内皮细胞缺氧过程中介导了F-actin的损伤,用RhoA-Rock信号通路抑制剂干预可以为新生儿肺出血的治疗研究提供一个新的方向.