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The authors describe a modification of the method of transauricular hypophysectomy. Anatomical reference-points suggested permit to direct the extractor directly to the gland without any use of additional instruments (goniometers, apparatus for fixation of the animal head, etc.). A detailed description of the course of the operation and of the instruments used is presented.
A integrity wheat component quickly measuring apparatus which based on NIR LED was developed, by using new chip and designing software. While providing a lower cost apparatus, it also provides quick answer speed and smaller size for fieldwork of wheat's components measuring. The apparatus is made up of NIR LED, interference filter, lens, Si photronic detector, microprocessor system and calibration model. Compared with other instrument, the apparatus has many advantages, such as compact space, simple structure, low power waste, and anti-shake. This paper introduces the design of the apparatus, and predicts the concentration of wheat protein. The apparatus can realize non-damage measurement of wheat components' concentration on fieldwork.
The particulate matter content of six commonly used types of large-volume parenteral solutions was evaluated using five methods. The five methods were: (1) visual examination with the naked eye under diffuse light, (2) visual examination with a 2.5 diopter lens under diffuse light, (3) examination with a light scattering apparatus, (4) instrumental examination using the Prototron particle counter, and (5) a membrane filtration and microscopic examination technique. The visual methods (1) and (2) proved to be inadequate because of the insensitivity and high degree of subjectivity. The light-scattering apparatus was reasonably accurate and a considerable improvement over the first two techniques. The Prototron instrument was shown to be capable of predicting whether a solution would pass or fail the recently adopted USP-NF standards for particulate matter content, when compared with the membrane filtration and microscopic examination technique. All of the solutions tested were found to contain very low levels of particulate matter in relation to the USP-NF standard. It is recommended that this recently adopted standard be reevaluated with a view toward increased stringency.
One of the most important conditions for obtaining reproducible microbiological results by disinfecting drycleaning is a control of the relative humidity of the drycleaning bath. An apparatus called "Wasserkontroller" (see Fig. 1) had been recommended as a device for the determination of the relative humidity. It consists of a special cylindrical casing into which the sensor of a hair hygrometer has been introduced. In contrast to electric instruments, this apparatus has the advantages of rigidity, simple adjustment, and above all of a low cost price. In practice, however, the "Wasserkontroller" proved to be a failure, since it indicated false values at times. In the studies published and discussed in the present paper, the causes for the malfunction of the hair hygrometer, in the device mentioned were determined. It could be observed that a malfunction of the hair hygrometer mainly occurred when the hairs fixed in the sensor were moistened by the drycleaning bath or by the drycleaning solvent (perchloroethylene), respectively. Then the hair hygrometer is no longer capable of reacting sufficiently to the fluctuation of the relative humidity of the bath. On the basis of the experimental results obtained instructions are given for the employment of hair hygrometers in drycleaning and for the design of the device casing: 1. The hair hygrometer has to be protected inside the device casing against a contamination by the bath or the condensing drycleaning solvent. 2. The inlet pipes to the device casing and the casing itself have to be protected against loss of heat as well as against the influence of heat sources. Temperatures of drycleaning bath and device should be balanced. 3. The inlet pipes to the device should be provided with a flowmeter or a flow detector, respectively. 4. The outlets of the device should be connected directly with the drum filled with the drycleaning bath. 5. The device has to be constructed in such a way that no infiltrated air may be sucked in. 6. The hair hygrometer has to be cleaned and to be adjusted at suitable time intervals. Provided that the technical requirements are met, hair hygrometers may also be considered as reliable measuring instruments in the practice of drycleaning.
In two separate experiments, male rats received septal lesions and were compared to operated controls on the acquisition of a two-way active avoidance task. In both experiments, an automated active avoidance apparatus (Lafayette Instrument Co.) was used, and the animals were tested 10 trials each day, 6 days/week. The CS was a tone, and the US was a 0.7 mA shock; the CS-US interval was 7 seconds. In Experiment 1, the rats (N = 6/group) were tested under conventional conditions. The two compartments of the avoidance apparatus were identical in all respects. In Experiment 2, the rats (N = 6/group) were tested in the same apparatus, but with differential intrabox cues. The inside of the left compartment was lined with black contact paper, while the inside of the right compartment was lined with white contact paper. Irrespective of the conditions, the septal rats were facilitated in the acquisition of shuttle-avoidance. In both tasks, the septal subjects required fewer trials to reach criterion, and showed better orientation in the shuttle-box compared to controls. The response latencies of the septal subjects also tended to be faster, but neither septal nor control subjects showed differential response latencies related to the direction of the shuttle response. Previous findings have shown that the addition of external cues to purported spatial tasks can reduce the behavioral effects produced by damage to the septohippocampal axis on such tasks. The present results suggest that such a cue-addition procedure does not influence the behavioral effects produced by septal lesions in shuttle-avoidance.
The proliferation of large-scale DNA-sequencing projects in recent years has driven a search for alternative methods to reduce time and cost. Here we describe a scalable, highly parallel sequencing system with raw throughput significantly greater than that of state-of-the-art capillary electrophoresis instruments. The apparatus uses a novel fibre-optic slide of individual wells and is able to sequence 25 million bases, at 99% or better accuracy, in one four-hour run. To achieve an approximately 100-fold increase in throughput over current Sanger sequencing technology, we have developed an emulsion method for DNA amplification and an instrument for sequencing by synthesis using a pyrosequencing protocol optimized for solid support and picolitre-scale volumes. Here we show the utility, throughput, accuracy and robustness of this system by shotgun sequencing and de novo assembly of the Mycoplasma genitalium genome with 96% coverage at 99.96% accuracy in one run of the machine.
In an investigation of the use of disinfectants in hospitals, the replies received from 338 institutions were analysed and subsequently compared with those obtained from southern Italy. It was found that benzalkonium chloride was the substance most widely used in Italy for disinfection of the surgical field, wounds, excoriations, sores, the skin prior to injections, surgical instruments, medical apparatus, catheters, thermometers and sanitary appliances, whereas chlorhexidine was preferred for disinfection of the hands, and for ambient surfaces in combination with cetrimide. Formic aldehyde was preferred for ambient surfaces, the air of confined spaces, and, in conjunction with chlorine and its derivatives, for sanitary services and their vessels. Glutaraldehyde was the substance most commonly employed for the disinfection of medical apparatus fitted with optic fibre lenses. In southern Italy, by contrast with the position in Italy as a whole, there was a greater use of chlorine and its derivatives for the disinfection of ambient surfaces, benzalkonium chloride for the disinfection and cleaning of sanitary services, vessels, and equipment with optic fibres, and alcohols for the disinfection of surgical instruments and sanitary appliances.
Telerobotics is a wide term and include multiple directions and aspects in its development. When speaking of different aspects of its development, one should think of its functionality, construction aspects, communication aspects, implementation safety and acceptance by the environment. Robotics is a science dealing with possibilities of implementing different tasks, through mechanical instruments, controlled by humans. Telesurgery does not include only aspects of teleconference but assists in surgical procedures, i.e. enables for the part of surgical procedure to be performed through electronic commands on bigger distances. Currently, two robotic systems are employed in clinical practice. One is ZEUS system, constructed by the Computer Motion and manufactured by AESOP. Second one is Da Vinci surgical system. For laparoscopic robotic telesurgery, identical set of apparatus and instruments as the one used in a routine laparoscopic surgical procedures is needed. In all reports, authors refer to safe and successful surgical method. Recovery of the patient is identical as in classic laparoscopy. No statistically significant difference has been found in the duration of the surgery between robotic and classic laparoscopy. When counting used instruments, it was found that less instruments were used in the robotic laparoscopy. From presented studies related to the robotic laparoscopy, it can be seen that there is an intention to present this method as safe and usable. One thing is sure--this method is the first step toward new model of planning and performing surgical procedures with only one goal--to help the patient.
HYPOTHESIS: The aim of this study is to present the therapeutic methods and surgical techniques in diseases of the ear during Byzantine times (324-1453 A.D.). BACKGROUND/METHODS: The original Greek language texts of the Byzantine medical writers were studied to research early otologic knowledge of symptomatology, conservative treatments, and surgical confrontation of diseases of the ear. RESULTS: A considerable number of conservative treatments for many otologic conditions were identified; these therapies were especially based on herbs, animal and mineral substances applied either as eardrops, clysters, poultices, or by using special instruments and apparatus. Among these were identified otitis, rupture of the eardrum, hemorrhage from the ears, deficiency of hearing and deafness, vertigo, tinnitus, and earwax. Furthermore, in these early texts, there were also described some surgical techniques in cases of atresia of the external auditory canal, of defects in or lack of the pinna, and for removal of foreign bodies and fleshy tumors. Some of the earliest hearing aids were also mentioned. CONCLUSIONS: From the study of the original works of Byzantine writers, it is evident that numerous treatments and surgical techniques relating to otology were practiced; these were derived not only from compilation of knowledge obtained from the ancient Greek medical sources, a considerable part of which are now lost, but also enriched by Byzantine physicians' personal experience. This knowledge influenced medieval European medicine and, through it, that of the rest of the world.
A facility for the exposure of small animals to pulse-modulated microwave radiation (PM MWR) concurrent with their performance of operant behavioral tasks is described. The computer-managed facility comprises an array of 32 individual waveguide exposure cells, each enclosing instrumental conditioning apparatus within a plastic subhousing. The distribution of the microwave electric field intensity within the waveguide was measured by a nonperturbing probe and the modifications induced by the behavioral apparatus and animal within the waveguide determined. Input and interior voltage standing-wave ratios are presented to characterize the design of the chambers and to demonstrate the suitability of the chambers for whole-body irradiation of rat. The specific absorption rate (SAR) is presented utilizing data derived from incremental thermometric examination of saline loads and of selected sites in rat carcasses. This is compared with the whole-body SAR derived from the input/output energy balance equation for the waveguide. The results of continuous monitoring of the SAR by the latter method, while unrestrained rats were engaged in operant and exploratory behavior within the waveguide, are utilized to derive a relationship between chamber input power and the dose rate for adult rats behaviorally active within the waveguide. From these data, we conclude that the experimental array provides a practical method for exposing a large number of animals to PM MWR for long periods of time and coincident with the establishment and/or performance of complex operant behavior.
In a repeated-measures experiment 18 men and 8 women were given ethanol which raised their mean blood alcohol concentration (BAC) to 0, 21, 50 and 73 mg/100 ml. Using the ERM apparatus (Schuhfried Instruments, Austria), which measures choice reaction time to a task with high cognitive content, it was found that both decision and reaction time increased as a function of rising BAC, and that movement time was not affected.
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BACKGROUND: The aim of this study is to gain insight into the problems encountered by the medical team related to products used for minimally invasive surgery. METHODS: An inventory was made of the problems encountered during 12 endoscopic operations performed in one city hospital (Eindhoven, the Netherlands). After the observation, a questionnaire was distributed to all medical staff involved. RESULTS: All categories of personnel had physical, perceptional, and cognitive problems, especially surgeons, residents, and the sterile operation nurse. The main causes were the positioning of apparatus and staff, work clothing, and the limited reach of apparatus and/or instruments. Of the questionnaires, 80% were returned: 50% of the medical staff experienced perceptional problems and 63% had physical discomfort during the surgical procedure. CONCLUSION: The diversity of problems observed and/or reported by the staff during minimally invasive surgery decrease the comfort, efficiency, and safety of the operating-room work environment. Therefore, a new design approach is needed for MIS products in order to address the problems that occur with the current equipment.
Microgravity experiments designed for execution in Get-Away Special canisters, Hitchhiker modules, and Reusable Re-entry Satellites will be subjected to launch and re-entry accelerations. Crew-dependent provisions for preventing acceleration damage to equipment or products will not be available for these payloads during flight; therefore, the effects of launch and re-entry accelerations on all aspects of such payloads must be evaluated prior to flight. A procedure was developed for conveniently simulating the launch and re-entry acceleration profiles of the Space Shuttle (3.3 and 1.7 x g maximum, respectively) and of two versions of NASA's proposed materials research Re-usable Re-entry Satellite (8 x g maximum in one case and 4 x g in the other). By using the 7 m centrifuge of the Gravitational Plant Physiology Laboratory in Philadelphia it was found possible to simulate the time dependence of these 5 different acceleration episodes for payload masses up to 59 kg. A commercial low-cost payload device, the "Materials Dispersion Apparatus" of Instrumentation Technology Associates was tested for (1) integrity of mechanical function, (2) retention of fluid in its compartments, and (3) integrity of products under simulated re-entry g-loads. In particular, the sharp rise from 1 g to maximum g-loading that occurs during re-entry in various unmanned vehicles was successfully simulated, conditions were established for reliable functioning of the MDA, and crystals of 5 proteins suspended in compartments filled with mother liquor were subjected to this acceleration load.
BACKGROUND: The optimal temperature for cardiac allograft storage remains controversial. We conjectured that supplementation of the potent cardioprotective agent 2,3-butanedione monoxime with calcium may improve allograft storage and make the precise storage temperature less critical. METHODS: Hearts were harvested from Sprague-Dawley rats (250 to 350 g), mounted on a Langendorff apparatus, and instrumented with an intraventricular balloon. Hearts were flushed and stored with either unmodified University of Wisconsin solution (UWS) or UWS supplemented with 10 mmol/L of 2,3-butanedione monoxime and calcium 0.1 mmol/L (BDM). Hearts were then subjected to 12 hours of storage at one of five temperatures (0 degree, 4 degrees, 8 degrees, 12 degrees, or 16 degrees C) in a complete 2 x 5 factorial design (n = 6/group). Data are reported either as a percentage of the prestorage results or as an absolute value (mean +/- standard deviation). RESULTS: Recovery of developed pressure (p < 0.0001), coronary flow (p < 0.0001), and diastolic volume (p < 0.001) were significantly enhanced, whereas creatine kinase (p < 0.0001) and lactate dehydrogenase release (p < 0.0001) were reduced in the BDM versus the UWS groups. In both the BDM and UWS storage groups, recovery was better at temperatures of 8 degrees C or less than at 12 degrees C or more. The single preferred temperature was 4 degrees C, significantly better than 0 degree C with unmodified UWS, while similar to 0 degree and 8 degrees C with BDM. Adenine nucleotide values were decreased equally in the BDM and UWS hearts, but preservation was enhanced at 0 degree C compared with all warmer temperatures. CONCLUSIONS: We conclude that 4 degrees C is the preferred temperature for prolonged cardiac storage with UWS and that the inclusion of 2,3-butanedione monoxime with calcium 0.1 mmol/L markedly enhances recovery for storage temperatures of 8 degrees C or less.
We studied whether applying nucleus pulposus tissue, obtained from tail intervertebral discs that had been subjected to chronic mechanical compression, to the lumbar nerve roots produces hyperalgesia, which is thought to be a pain-related behavior in the rat. An Ilizarov-type apparatus was used for immobilization and chronically applied compression of the rat tail for eight weeks. Three weeks after application of extracted nucleus pulposus tissue on the lumbar nerve roots, motor function, sensitivity to noxious mechanical stimuli was measured. Eight weeks after application of the apparatus, the instrumented vertebrae were resected and sections were stained with hematoxylin and eosin to evaluate degeneration of the intervertebral disc. Mechanical hyperalgesia observed in rats treated with the compressed nucleus pulposus tissue was greater and of longer duration than in the rats treated with normal and non-compressed discs. The nucleus pulposus in the instrumented vertebrae showed some histological degeneration. In conclusion, chronic mechanical compression of nucleus pulposus, which resulted in degeneration to some extent, enhanced mechanical hyperalgesia, which was induced by application of nucleus pulposus on the nerve root in the rat. Degenerative intervertebral discs might induce more significant pain than normal intervertebral discs.
Assessment of iodine deficiency and monitoring of iodine supplementation programs demands rapid, simple and cost-effective methods for the determination of urinary iodide concentrations. We propose a rapid test based on the iodide-catalyzed oxidation of 3,3',5,5'-tetramethylbenzidine by peracetic acid/H2O2 to yield colored products. The color of the chemical reaction is compared with color categories of a pictogram corresponding to three ranges (<10, 10-30, and >>30 microg/100 mL) of iodide concentrations. The test is very easy to perform and does not require any instrumentation or apparatus. Sample preparation is simple and consists in the removal of interfering substances by disposable columns, 65 x 10.5 mm, packed with specifically prepared activated charcoal. For comparison with a reference method for measuring urinary iodide (HPLC), we determined the iodide concentrations of 370 random (untimed) urine samples from consecutive patients by both HPLC and the rapid test. The results obtained by both methods are in close agreement with respect to classification of the samples according to the above three ranges, with a maximum difference of <5% for each range. This rapid test is therefore very well suited to epidemiological surveys of iodine deficiency especially in developing countries.
Since their invention just over 20 years ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology and physics. Capabilities have evolved from simple manipulation to the application of calibrated forces on-and the measurement of nanometer-level displacements of-optically trapped objects. We review progress in the development of optical trapping apparatus, including instrument design considerations, position detection schemes and calibration techniques, with an emphasis on recent advances. We conclude with a brief summary of innovative optical trapping configurations and applications.