The cold pressor test: Vascular and myocardial response patterns and their stability

The purposes of the present study were to compare the cardiovascular response patterns evoked by three versions of the cold pressor test (either forehead stimulation or hand or foot immersion) and to determine the reproducibility of the responses over a 2-week interval. Blood pressure, heart rate, stroke volume, cardiac output, total peripheral resistance, and systolic time intervals were obtained during rest and during the cold pressor test in 42 young men. Across conditions, the pressor response was supported by peripheral resistance increases with concomitant stroke volume decreases. Although the response panerns were generally similar across sites, exceptions were apparent for heart rate. Forehead stimulation was characterized by no significant change in heart rate, whereas limb (hand or foot) immersion was associated with significant heart rate acceleration. The responses elicited by the three cold pressor test conditions were reliable and showed little evidence of attenuation over the test-retest interval.     

Linkage guide for rotational alignment during total knee arthroplasty

A linkage guide was devised for use in conjunction with knee arthroplasty instruments to achieve proper component rotation. The femoral component was rotationally aligned to the surgical epicondylar axis using one guide. The other guides were used after all bone surfaces were cut and soft tissue balancing was completed. A Kirschner wire was guided into the proximal tibial aspect parallel to the sagittal plane of the femoral component with the patella in its normal position and the knee in full extension. The wire was used as a reference to determine tibial component rotation. The relative rotational alignment of 21 knees in 19 patients who had undergone cruciate-retaining total knee arthroplasty utilizing this guide was assessed using the modified Eckhoff method. The results of radiographic analysis were compared with those in a control group of 25 knees where the guide was not employed. The external rotation of the femoral component relative to the tibial component was 1.3° ± 2.0° (mean ± SD) in the guided group and 1.1° ± 4.4° in the control group. The relative rotational angle was significantly more consistent using the guide. Implant malrotation can be reduced using our technique.     

The application of percolation theory to the compaction of pharmaceutical powders

Based on the concepts of percolation theory the compaction process is interpreted as a site-bond percolation phenomenon. The combination of the Heckel equation with an equation derived earlier yields a simple relationship between the tensile strength σ_t, or the deformation hardness P and the relative density. This mathematical model is identical with the fundamental law of percolation theory i.e., X = s(p − p_c)^q with X= system property equivalent to tensile strength or deformation hardness, S = scaling factor, p = site occupation or bond formation probability corresponding to the relative density p,p_c = percolation threshold and critical exponent q = 1 according to percolation on a Bethe lattice. In the case of the tensile strength σ_t and the deformation hardness p, two percolation thresholds p_c(1) and p_c(2) corresponding to p_c(1) and p_c(2) could be identified. The relative density p_c(1) which is close to the relative poured or relative tapped density can be interpreted as a bond percolation threshold. The particles are bonded by weak interparticulate forces and form only loose compacts as used for filling of capsules. The relative density p_c(2) is the relative density where the first stable pharmaceutical compact is achieved which can no longer be disintegrated mechanically into its primary particles. It is of special interest that the above equation is also valid for the elastic modulus with the only percolation threshold p_c(1) = p_c(1).     

直肠癌全直肠系膜切除术后直肠阴道瘘原因与防治

本文通过分析近5年来我院18例女性直肠癌全直肠系膜切除术后直肠阴道痿的临床资料。发现直肠阴道痿多发生于中低位直肠癌行全直肠系膜切除保肛手术的患者。痿的发生与肿瘤的位置、肿瘤的分期、肿瘤距肛门口的距离．以及手术技巧、手术难度、引流方法有关。而与是否进行预防性造口，以及是否采用腹腔镜手术无关。预防上强调应重视术中直肠前壁的锐性分离、结肠直肠吻合以及术后盆腔的负压引流。治疗上应首先进行保守治疗，即肠内营养，阴道冲洗。早期配合肠外营养、及全身或局部抗炎治疗，大部分直肠阴道痿通过保守治疗可以治愈。保守治疗无效时考虑结肠或回肠末端造口。若长期不愈应考虑吻合口肿瘤复发的可能。     

冲击式二级采样对呼吸粉尘与总粉尘浓度比值的影响

为了验证冲击式二级粉尘采样对呼吸性粉尘与总粉尘浓度比值的影响，作者采用瞬时定点采样方法测定作业场所空气中呼吸性粉尘浓度与总粉尘浓度。结果表明，在采样体积相同的条件下，呼吸性粉尘的比值与总粉尘浓度间具有较好的从属共变关系（ｒ＞０．８），呼吸性粉尘的比值随着总粉尘浓度的升高而相应增大     

Middle-ear pressure variations during total intravenous anesthesia with propofol, fentanyl, and ketamine

Purpose As the middle-ear cavity is one of the noncompliant gas-filled cavities, an increase in middle-ear pressure (MEP) instead of volume expansion is observed with inhalation of nitrous oxide (N₂O). Changes in MEP cause many complications, such as ear pain, temporary hearing impairment, and postoperative emesis. Therefore, we investigated changes in MEP during total intravenous anesthesia (TIVA) with propofol, fentanyl, and ketamine (PFK) and inhalation of N₂O. Methods Twelve patients were anesthetized with PFK until 60 min after the induction of anesthesia, and then N₂O (60%) inhalation was started. MEP was measured by impedance audiometry (ranging from −300 daPa to +200 daPa) at 10-min intervals during PFK, and at 2-min intervals after the inhalation of N₂O. Results MEP gradually but significantly increased from the preanesthetic value of 16±8 to 34±12 (SEM) daPa 50 min after the induction of PFK. However, MEP did not exceed the normal limit. The values of MEP in all patients were more than 200 daPa within 36 min after the start of inhalation of N₂O in oxygen. Conclusion PFK had a minimal effect on MEP, whereas addition of N₂O to PFK increased MEP dramatically. Therefore, TIVA, or at least PFK, would be a better choice for patients with middle-ear or upper-airway diseases.     

Artificial nutrition support in intensive care units in Spain

Objective A multicenter survey to study the use of nutritional support in patients admitted to the ICU in Spain.Design The survey was announced during the annual Spanish Society of Intensive Care Medicine and Coronary Units (SEMIUC) congress meeting.Setting Questionnaires designed to determine current clinical practice concerning artificial nutrition were sent to the 27 ICU who accepted to participate.Patients and participants In each center the 235-question form was filled out individually for each patient admitted to the ICU during the month of March, 1992.Interventions To validate the study a preliminary pilot surveys were conducted to ensure that there was a correct interpretation of the questions. The replies were entered into a database for analysis.Results A total of 1261 patients were studied; 33.9% received artificial nutrition (AN). The administration of AN was significantly higher in the medical group (44%), than in the surgical (37%) and the trauma group (19%). AN was significantly lower in patients admitted to private clinic than public institutions (26.7% versus 34.7%). Among the patients who received AN, enteral nutrition (EN) was administered to 59.7% of the patients, total parenteral nutrition (TPN) to 38.5%, and peripheral parenteral nutrition (PPN) to 18.2%. Medical patients received significantly more EN than surgical and trauma patients. Surgical patients received more PN than medical and trauma groups.Conclusions Nutritional support is a common practice in the treatment of ICU patients in our country. All information concerning its use is necessary to optimize it.     

山楂叶总黄酮含量测定及抗氧化活性研究

目的:评价山西晋南地区采集的山楂叶中总黄酮的含量及体外抗氧化活性。方法:采用显色法测定总黄酮含量;通过对1,1-二苯基-2-苦基肼(1,1-diphenyl-2-picrylhydra-zyl, DPPH)、2,2-联氮-双(3-乙基苯并噻唑-6-磺酸)二铵盐(2,2′-azino-bis[3-ethylbenzothiazoline-6-sulfonic acid]diammonium salt, ABTS)和羟自由基的清除能力评价体外抗氧化活性。结果:山楂叶总黄酮含量为(79.06±2.05)mg/g。总黄酮对DPPH、ABTS自由基清除半数抑制浓度(half maximal inhibitory concentration, IC₅₀)分别为(91.63±1.75)和(64.34±4.53)μg/mL,与抗坏血酸相比,相对抗氧化活性(relative antioxidant activity, RAA)分别为40.71%和76.64%;对羟自由基清除率较低,三者均低于同质量浓度下的抗坏血酸。结论:山西晋南地区采集的山楂叶总黄酮含量较高,有较高的抗氧化活性,可...     

超声弹性成像技术联合血清学标志物预测2型糖尿病的应用价值

<正>多项研究表明,非酒精性脂肪性肝病患者(NAFLD)发生2型糖尿病(type 2 diabetes mellitus,T2DM)的风险是正常人的5倍^[1-3]。在T2DM患者中,NAFLD的患病率可高达70%^[4]。肝脏瞬时弹性成像技术(tran-sient elastography,TE)是近年来新兴的超声无创检查方法,主要基于超声信号在肝组织中传播受肝细胞中脂滴的影响而出现显著衰减的原理来评估肝脏脂肪性病变,