[Ethical, legal and medical aspects of transplantation].

Tissue and organ transplantation is a very complex interdisciplinary treatment, particularly in regard to unpaired organs, and it carries numerous risks for all participants in such an action. For the purpose of minimizing the risks to the allowed level and the preservation the humanitarian goals in medicine when performing the transplantation, professional and scientific doctrines and the respect of ethical and legal principles should be strictly observed. The paper presents the basic approaches in the estimation of justification, usefulness and certain forms of responsibility in the process of transplantation.

Effect of progressive haemodilution with hydroxyethyl starch, gelatin and albumin on blood coagulation.

We have compared the effects of progressive (30% and 60%) in vitro haemodilution with hydroxyethyl starch (HES), gelatin (GEL) and albumin (ALB) with haemodilution using 0.9% saline in 96 patients by thrombelastography. Haemodilution with HES, GEL and ALB significantly (P < 0.

Simple and rapid chromatographic method for the separation of major classes of ribosomal ribomononucleotides.

We have described a simple and rapid chromatographic method for the analytical and preparative separation of major types of ribosomal ribomononucleotides with Dowex 1-X10 (HCOO-, 37-74 microns) and Dowex 2-X10 (HCOO-, 37-74 microns) columns, by desorption with formiate solutions in 1-2 h. The separation has been achieved for Cp, Ap, Up and Gp, while a mixture of 2'-, and 3'-nucleoside phosphates desorbs as a single peak; with both resins, a successful separation was achieved with a load from 25 micrograms to 1 mg of ribomononucleotide mixture per ml of packed resin. A complete separation was achieved with Dowex 1, while the separation with Dowex 2 resin was even better.

[Endobronchial metastases in extrapulmonary malignant tumors].

Endobronchial metastases of extrapulmonary malignant tumors are very rare and they appear in 1-2% of all the pulmonary metastases cases. By their endoscopic presentation, they are similar to primary bronchogenic carcinoma. Eleven patients with endobronchial metastases were presented, 8 male and 3 female.

[Retroperitoneal marsupialization of renal cysts].

The use of minimal invasive surgery in urology continue to increase. Retroperitoneoscopic approach in performing minimal invasive surgery of retroperitoneum shortens the duration of operation in comparison with transabdominal approach, with minimal risk of intraabdominal complications. We described the use of the retroperitoneoscopic approach to the upper pole of a kidney for marsupialization of a symptomatic renal cyst.

Estimating mechanical parameters of leg segments in individuals with and without physical disabilities.

Methods are described for estimating the inertia, viscosity, and stiffness of the lower leg around the knee and of the whole leg around the hip that are applicable even to persons with considerable spasticity. These involve: 1) a "pull" test in which the limb is slowly moved throughout its range of motion while measuring angles (with an electrogoniometer) and torques (with a hand-held dynamometer) to determine passive stiffness and 2) a "pendulum" test in which the limb is moved against gravity and then dropped, while again measuring angles and torques. By limiting the extent of the movement and choosing a direction (flexion or extension) that minimizes reflex responses, the mechanical parameters can be determined accurately and efficiently using computer programs.

Perspectives on the role of afferent signals in control of motor neuroprostheses.

K.O. Johnson reviews the architecture and low level neural mechanisms by which the external environment is transduced and encoded into the neural system, summarizing work that correlates neurophysiological and psychophysical testing with isolation of sensory components.

A novel electric design for electromagnetic stimulation--the Slinky coil.

A novel coil design for inductive electromagnetic stimulation of neural cells has been simulated and experimentally tested. This coil improves the focal effect of a magnetic stimulator, and it reduces its inductance, hence the efficiency of the system is improved. The basic structure of the device is derived from the popular "Slinky" toy.

[Aspiration bronchopneumonia as a complication of acute poisoning with psychotropic drugs].

In the five year period, retrospectively and prospectively, the frequency, clinical, radiographic and bacteriological characteristics of the aspiration bronchopneumonia (ABPN) were followed in the acute poisoning by psychotropic drugs (PD). In 1769 patients with acute poisoning by PD, ABPN was determined in 44 (2.49%) patients, and most frequently in groups with polymedicamentous (5.

[Oral rehydration in the treatment of acute diarrhea in children].

Acute diarrhea is one the major causes of child ailments, regardless of their age and a frequent cause of infancy deaths. The Oral Rehydration is the recommended therapy for all patients suffering from mild and moderate dehydration, whatever the cause or the age of the child. A timely and properly administered oral rehydration effectively supplements the liquids and electrolytes deficiency, compensates for their continued loss and ensures physiological needs.

[Pharmacotherapy of gastrointestinal diseases in children].

The paper describes only the most frequent gastrointestinal diseases, as well as the ones which pose a problem in their diagnosis and therapy. The paper presents the clinical picture of acute enterocolitis, gastroaesophageal reflux, peptic ulcer, chronic ulcerative colitis and Crohn's diseases in children and the basic methods for the diagnosing of these diseases, with a special emphasis on the specific characteristics of the pharmacotherapy in the treatment of children. A special attention is devoted to the drugs choice and their dosage.

Machine learning in control of functional electrical stimulation systems for locomotion.

Two machine learning techniques were evaluated for automatic design of a rule-based control of functional electrical stimulation (FES) for locomotion of spinal cord injured humans. The task was to learn the invariant characteristics of the relationship between sensory information and the FES-control signal by using off-line supervised training. Sensory signals were recorded using pressure sensors installed in the insoles of a subject's shoes and goniometers attached across the joints of the affected leg.

An EMG-controlled grasping system for tetraplegics.

A two-channel, portable, battery operated, functional electrical stimulation (FES) system with surface electrodes to enhance grasping in tetraplegics was developed and tested. This system is meant for tetraplegics capable of grasping by tenodesis. Candidates for this system must retain some wrist extension, and have paralyzed but innervated finger flexors, and nearly normal shoulder and elbow coordination within the working space.

Optimal control for an above-knee prosthesis with two degrees of freedom.

Our previous research and clinical tests of a self-contained powered above-knee prosthesis (AKP) showed that a knee joint with one degree of freedom (DOF) increases the energy cost of walking with respect to able-bodied subjects. Better symmetry of the gait can improve performance, so we suggest here the integration of a second powered DOF into the knee joint mechanism to control the internal-external rotation of the shank-foot complex. The control for the AKP with two DOFs is based on a method of optimal tracking.

Instrumentation for ENG and EMG recordings in FES systems.

An electronic circuit for analog processing of neural (electroneurogram or ENG) and muscular (electromyogram or EMG) signals in functional electrical stimulation (FES) systems is described in this paper. The basic circuit consists of a low-noise gated preamplifier, band-pass filter, amplifier, and a blanking circuit to minimize stimulation artifacts during electrical stimulation. This device was tested in chronic recordings using a triphasic cuff electrode for nerves and epimysial electrodes for muscles in the hind limbs of cats.

A new approach to reaching control for tetraplegic subjects.

A simple upper limb control strategy to guide reaching in preparation to grasp for tetraplegic subjects is proposed. The control is based on new studies of self-paced human arm movements involving rotations about the shoulder and elbow joints. An experimental study of reaching, while grasping, by able-bodied humans, allowed us to reduce the dimensionality of the control vector from two to a single variable.

Sensory nerve recording for closed-loop control to restore motor functions.

A method is developed for using neural recordings to control functional electrical stimulation (FES) to nerves and muscles. Experiments were done in chronic cats with a goal of designing a rule-based controller to generate rhythmic movements of the ankle joint during treadmill locomotion. Neural signals from the tibial and superficial peroneal nerves were recorded with cuff electrodes and processed simultaneously with muscular signals from ankle flexors and extensors in the cat's hind limb.

Electrical systems for improving locomotion after incomplete spinal cord injury: an assessment.

Simple systems for electrical stimulation (1-4 channels) with either surface, percutaneous, or implanted electrodes during locomotion were assessed in 10 subjects who had chronic, incomplete spinal cord injury (SCI). On average, the speed of locomotion was increased by 4 m/min independently of the subject's speed of locomotion without stimulation (0-50 m/min) while oxygen consumption was reduced somewhat. These simple systems can provide practical help, particularly for incomplete SCI subjects who can stand but are lacking or have very limited ability to walk.

Output space tracking control for above-knee prosthesis.

The control of a knee joint in an active above-knee prosthesis has been designed using the Lyapunov tracking method. A simulation of locomotion was done to prove that the tracking control in output space is a valuable real time control method for artificial legs. The data used for simulation was collected in able-bodied subjects while they walked on a powered treadmill.

[The obstruction syndrome in patients with bronchogenic carcinoma].

In the period 1985-1990, 760 patients with bronchogenic carcinoma have been examined and treated at the Clinic of Lung Diseases of the Military Medical Academy. Obstruction syndrome was found in 64% of patients of whom 21% with severe obstruction. Pulmonary insufficiency, most commonly of milder, partial type, was found in 19% of patients.

Finite state model of locomotion for functional electrical stimulation systems.

A finite state model of locomotion was developed to simplify a controller design for motor activities of handicapped humans. This paper presents a model developed for real time control of locomotion with functional electrical stimulation (FES) assistive systems. Hierarchical control of locomotion was adopted with three levels: voluntary, coordination and actuator level.