Set Positive End-expiratory Pressure during Protective Ventilation Affects Lung Injury

Background: The most appropriate method of determining positive end-expiratory pressure (PEEP) level during a lung protective ventilatory strategy has not been established.

Methods: In a lavage-injured sheep acute respiratory distress syndrome model, the authors compared the effects of three approaches to determining PEEP level after a recruitment maneuver: (1) 2 cm H2O above the lower inflection point on the inflation pressure-volume curve, (2) at the point of maximum curvature on the deflation pressure-volume curve, and (3) at the PEEP level that maintained target arterial oxygen partial pressure at a fraction of inspired oxygen of 0.5.

Results: Positive end-expiratory pressure set 2 cm H2O above the lower inflection point resulted in the least injury over the course of the study. PEEP based on adequate arterial oxygen partial pressure/fraction of inspired oxygen ratios had to be increased over time and resulted in higher mRNA levels for interleukin-8 and interleukin-1[beta] and greater tissue inflammation when compared with the other approaches. PEEP at the point of maximum curvature could not maintain eucapneia even at an increased ventilatory rate.     

先天性视网膜色素上皮肥大对家族性腺瘤性息肉病的筛查

对8例家族性腺瘤性息肉病(FAP)5名I级高危亲属和100例对照组作眼底色素病变研究。结果表明：先天性视网膜色素上皮肥大对FAP有筛检价值，若色素斑有晕圈、数量≥4颗、病变为双眼且位于后极部，则FAP的可能性很大。 （中华眼底病杂志，1995，11：1-3）     

Hemorrhage during Isoflurane-Nitrous Oxide Anesthesia: Effects of Endothelin-A or Angiotensin II Receptor Blockade or Both

Background: The objective of this study was to determine whether endothelin-A receptor blockade (ETAB) impairs hemodynamic and hormonal regulation compared with controls and angiotensin II receptor blockade (AT1B) during hypotensive hemorrhage in dogs under isoflurane-nitrous oxide anesthesia.

Methods: Six dogs were studied in four protocols: (1) control experiments (controls); (2) ETA blockade using ABT-627 (ETAB); (3) AT1 blockade using losartan (AT1B); and (4) combined AT1B and ETAB (AT1B + ETAB). After a 30-min awake period, isoflurane-nitrous oxide anesthesia was established (1.3 minimum anesthetic concentration). After 60 min of anesthesia, 20 ml blood/kg body weight was withdrawn within 5 min, and the dogs were observed for another hour. Thereafter, the blood was retransfused, and the dogs were observed for a final hour.

Results: Anesthesia: Cardiac output decreased in all protocols, whereas mean arterial pressure decreased more in AT1B and AT1B + ETAB than in controls and ETAB. Hemorrhage: After 60 min, cardiac output had decreased less in controls than in all other protocols. Mean arterial pressure decreased more during ETAB than in controls, but most severely during AT1B and AT1B + ETAB. Angiotensin II increased further only in controls and ETAB, whereas vasopressin and catecholamines increased similarly in all protocols. Retransfusion: Mean arterial pressure remained below controls in all protocols but was lowest when the AT1 receptor was blocked. Cardiac output fully recovered in all but the ETAB protocol.     

增殖性玻璃体视网膜病变性视网膜脱离的手术治疗

报告189例189眼严重增殖性玻璃体视网膜病变(PVR)性视网膜脱离，单纯巩膜扣带术和玻璃体切除术的结果，平均解剖成功率63%，从C₁87.5%至D₃30.4%。术后复位成功的病例95.8%有指数以上的视力，但仅26.9%达0.1以上，且多集中于C₁和C₂组。手术失败的主要原因是新的或复发的前段PVR形成(51.4%)，其次为后部视网膜前膜增殖，将原裂孔拉开或形成新裂孔(25.7%)。就PVR性视网膜脱离的手术时机，手术方式及前段PVR的形成进行了讨论。 （中华眼底病杂志，1994，10：199-202）     

脉络膜恶性黑色素瘤九例报告

回顾分析我院病理证实的9例脉络膜恶性黑色素瘤患者的临床及病理资料．患者平均年龄42岁。7例眼底可见，其中6例为孤立性肿块，1例视网膜穿破；8例B超检查发现眼内实质性占位病变；2例眼底荧光血管造影显示瘤体自身异常血管显影及斑驳状荧光：病理分型梭形A细胞型5例，梭形B细胞型3例，上皮样细胞型1例。眼底荧光血管造影的异常表现可为本病的一种诊断特征，对屈光间质混浊的不明原因青光眼病人，B超检查有助于减少本病误诊． （中华眼底病杂志，1995，11：95-96）     

Economy of Adaptation to High Altitude

TheinternationalmeetingthatwillbeheldinXin ingandLhasainAugust 2 0 0 4willbeawonderfulocca siontosharefactsandconceptsdealingwithadaptationtohighaltitude .Lifeathighaltitudeisachallengeforthou sandsofanimalspeciesandmillionsofhumansresidingorvisitinghigha…