Anatomy of the hyoid apparatus in odontoceli (toothed whales): Specializations of their skeleton and musculature compared with those of terrestrial mammals

Background: The hyoid apparatus of odontocetes (toothed whales) serves as a major attachment point for many of the muscles and ligaments subserving breathing, swallowing, and sound production. Methods: This study examines the hyoid apparatus in 48 specimens of ten odontocete genera (Phocoena, Lagenorhynchus, Stenella, Delphinus, Tursiops, Grampus, Globicephala, Mesoplodon, Physeter, and Kogia) collected post mortem from beach strandings. Results: The odontocete hyoid apparatus, as that of their closest terrestrial relatives, the artiodactyls, is divisible into a basal portion (bashyal, paired thyrohyals) and a suspensory portion (paired ceratohyals, epihyals, stylohyals, and tympanohyals) connecting the basal portion to the skull base. Unlike other terrestrial mammals, the basal portion lies inferior to the laryngeal aditus, is flattened dorso-ventrally, and is relatively large, thus providing a broad surface area for muscle attachments. The suspensory elements are not as flattened and are joined by synovial joints (except for epihyal-stylohyal fusion). Muscular specializations include enlargement of those which retract the hyoid apparatus (e.g., sternohyoid) or control the tongue (e.g., styloglossus, hyoglossus). These muscles may be particularly important in a specialized prey capture behavior called suction feeding. In addition, the hyoid apparatus has a tilted placement, which allows asymmetrical enlargement of the piriform sinuses. Asymmetry is also seen in the muscular attachment between the larynx and the hyoid apparatus. The most pronounced differences from the basic pattern are observed in two families: Physeteridae and Ziphiidae. Conclusions: The derived position and shape of the odontocete hyoid apparatus may have evolved to subserve several specialized upper respiratory/digestive tract functions, such as simultaneous feeding (suction and swallowing) and sound production. © 1994 Wiley-Liss, Inc.     

Effects of fixed-interval duration on the development of tolerance to decreased responding byl-nantradol

The effects of several types of antidepressants in a recently developed behavioural despair model, the tail-suspension test, are described. Drug effects on the automatically recorded duration of immobility and power of movements were measured in three strains of mice. Only in one strain (NMRI) did almost all antidepressants tested showed the expected reduction in duration of immobility. Tranquillizing drugs, but not stimulants, could be distinguished from antidepressants. The power of movements could not definitively be related to the pharmacological profile of the drugs tested. The use of the tail-suspension test as a rapid and highly predictive behavioural primary screen for antidepressant drugs is suggested.     

红细胞聚集与取向对其悬浮液电阻抗的影响——I.实验研究

本文通过测量具有不同流变特性的红细胞悬浮液电阻抗的动态与静态变化，研究了红细胞聚集与取向对其悬浮液电阻抗的影响。首次得出以下结论：１．红细胞聚集使其悬浮液电阻抗显著减小。２．由于低切变率下红细胞聚集与高切变率下红细胞取向的共同影响，使血液电阻抗随切变率的变化具有双相特性。这增加了对血液电特性的新认识，表明可利用电阻抗测定红细胞聚性。     

聚乙烯醇在α-Al_2O_3颗粒上的吸附平衡

考察了温度、悬浮液浓度、相对分子质量对聚乙烯醇 ( PVA)在 α- Al2 O3颗粒上吸附的影响 ,实验测定了相对分子质量为 80 0 0 0和 56 0 0的 PVA在 2 88.1 5K、2 98.1 5K和 30 8.1 5K、α- Al2 O3悬浮液质量浓度为 0 .0 5、0 .1 0和 0 .1 5时的吸附等温线 ,用 Langmuir吸附模型对实验数据进行了关联。结果表明 ,吸附量随悬浮液浓度的增加或温度的升高而降低 ,随 PVA相对分子质量的增加而增加。PVA相对分子质量越大 ,其吸附等温线受温度、悬浮液浓度的影响也越大。     

Gastrointestinal absorption of phenytoin from an oil-in-water microemulsion

The absorption profile of phenytoin Na emulsion were examined compared to that of phenytoin suspension after oral administration in the rat. The corn oil-in-water emulsion, particle size of 184±57.8 nm, was prepared using a microfludizer, and phenytoin Na added by shaft homogenizer. The phenytoin emulsion or suspension, 100 mg/kg, were intubated intragastrically using oral dosing needle and blood samples were withdrawn via an indwelling cannula from the conscious rat. Plasma concentrations of phenytoin were measured with HPLC using phenacetin as an internal standard. The plasma concentration versus time data were fitted to a one compartment open model and the pharmacokinetic parameters were calculated using the computer program, Boomer. The phenytoin plasma concentrations from the emulsion at each observed time were about 1.5–2 times higher than those from the suspension, significantly at time of 5, 6 and 7 hr after administration. The absorption (k_a) and elimination rate constant (k_e) were not altered significantly, however the AUC increased from 65.6 to 106.7 μg·hr/ml after phenytoin suspension or emulsion oral administration, respectively. From an equilibrium dialysis study, the diffusion rate constant (k_IE) was considerably higher from the phenytoin Na emulsion (0.0439 hr⁻¹) than phenytoin suspension (0.0014 hr⁻¹).     

Successful treatment of tracheomalacia associated with esophageal atresia without a tracheoesophageal fistula by aortopexy: Report of a case

Tracheomalacia (TM) is well known as a complication associated with esophageal atresia (EA) and tracheoesophageal fistula (TEF); however, the occurrence of TM requiring surgical treatment in a patient having EA without a tracheoesophageal fistula has never been reported. We describe herein a rare case of TM associated with EA without TEF. Respiratory distress was caused by compression of the trachea by a severely dilated upper esophageal pouch with weakness of the tracheal wall. Aortopexy was performed, and an excellent postoperative result was achieved.     

含药树脂微囊法制备口服缓释混悬液Ⅰ.右美沙芬口服缓释混悬液

采用含药树脂微囊法制备了右美沙芬口服缓释混悬夜，研究了影响含药树脂药物吸附和释放的因素及体外释药和健康志愿者体内的药动学。结果表明该混悬液在服用12h后，尚有101．9ng／m1的有效血药浓度。     

Magnetically suspended rotary blood pump with radial type combined motor-bearing

A magnetically suspended centrifugal blood pump is being developed with a combined motor-bearing for long-term ventricular assist systems. The combined motor-bearing actively suspends a rotor in a radial direction to deal with radial force unbalance in the pump and rotates the rotor by using the electric magnetic field. Therefore, the pump has no mechanical parts such as bearings of the motor and has a long lifetime. The developed pump consists of a thin rotor with a semi open-type 6 vane impeller and a stator to suspend and rotate the rotor. The rotor has 4-pole permanent magnets on the circumferential surface. The outer diameter and the thickness of the rotor are 60 mm and 8 mm, respectively. Axial movement and tilt of the rotor are restricted by passive stability based on the thin rotor structure. Radial movements of the rotor, such as levitation in radial direction and rotation, are controlled actively by using electric magnets of the stator. The electric magnet coils to produce levitation and rotation forces are constructed on the periphery stator. The p +/- 2-pole algorithm and the synchronous motor mechanism are adopted to levitate and rotate the rotor. The radial gap between the rotor and the stator is 1 mm. A closed-loop circuit filled with water was connected to the developed pump to examine the basic performance of the pump and the magnetic suspension system. Maximum rotational speed, flow rate, and head were 2,800 rpm, 11 L/min, and 270 mm Hg, respectively. The rotor with the impeller could be suspended completely during the entire pumping process. We conclude the pump with the combined motor-bearing has sufficient performance for the blood pump.     

真菌诱导子对胡桐悬浮培养细胞产生红厚壳素的影响

目的探讨真菌诱导子对胡桐悬浮培养细胞产生红厚壳素的影响。方法通过对胡桐叶斑病病菌的分离培养,制成真菌诱导子补加到胡桐细胞悬浮培养基中,考察不同浓度、不同加入时间对胡桐细胞生物量及红厚壳素产量的影响。结果S-I菌株诱导胡桐CR2细胞合成红厚壳素的最佳浓度为60 mg GE·L^-1,诱导子在细胞生长静止期初期(即培养d 18)加入对红厚壳素产量影响最大,可使产量提高27%,并促进了红厚壳素向胞外分泌。结论 壳多孢菌的添加能有效提高胡桐细胞悬浮培养体系中红厚壳素的产量。