SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
The case records of the Psychological Clinic of the University of Pennsylvania the first established in this country, have been transferred to microfilm to save them from desctruction. A survey of the records indicate that they may be valuable in both historical and follow-up research. The microfilms can be made available to qualified investigators with worthy projects.
An assessment of alternative methods of filing histopathology report forms in alphabetical order showed that orthodox card index filing is satisfactory up to about 100000 reports but, because of the need for long-term retrieval, when the reports filed exceed this number they should be copied on jacketed microfilm and a new card index file begun.
Considerations on the theory of communication point to the importance of "redundant" data in medicine. These usually arise from texts such as catamneses, descriptions of findings etc., and escape digital data pooling and storage on organizational and financial grounds. Here, microfilm is available as an economical storage medium taking little room. Developments in recent years enable integration of automatic analog storage into digital information systems. The use of such a hybrid system in the field of pathology is described.
As elsewhere, in medicine it has become evident that the "pure" ideal of on-line, full-text real-time computerized systems offers no panacea for the diverse information problems of researchers, practitioners, and administrators. More flexible, efficient and economical possibilities are available in the form of "hybrid" systems of computers and other techniques, such as micrographics and COM. There are a number of alternative strategies. LORBAS is one family of such systems. LORBAS is based on a mini-microfilm technique (reduction ratio to 250:1, up to 200,000 pages per liter), permitting rapid digital random access to every page. The computer is used off-line for the administration of the system and for generating a variety of retrieval aids which are worked into the film inventory (through COM). Numerous user stations can be equipped with the full document basis(incl. the retrieval aids), and operated off-line. On-line linkage is optional on every desired level of sophistication.
Works in the natural sciences are provided with comparatively less copyright protection than literary works. Nevertheless, this protection is important for scientists. However, more recently, modern methods and techniques of information and documentation, such as reprography, microfilm archives, electronic data storage and retrieval, and data transmission have questioned the justification and effectiveness, even in principle, of this protection. A more detailed analysis demonstrates that this involves not so much a crisis of copyright law as a crisis of the entire field of scientific information.
1H nuclear magnetic resonance (NMR) spectra of a self-complementary ribosyl hexanucleotide, A2GCU2, are investigated as a function of temperature and ionic strength in D2O. Seventeen nonexchangeable base and ribose-H1' resonances are resolved, and unequivocally assigned by a systematic comparison with the spectra of a series of oligonucleotide fragments of the A2GCU2 sequence varying in chain length from 2 to 5. Changes in the chemical shifts of the 17 protons from the hexamer as well as the six H1'-H2' coupling constants are followed throughout a thermally induced helix-coil transition. These sigma vs. T and J vs. T (degrees C) profiles indicate that the transition is not totally cooperative and that substantial populations of partially bonded structures must exist at intermediate temperatures, with the central G-C region being most stable. Transitions in chemical shift for protons in the same base pair exhibit considerable differences in their Tm values as the data reflect both thermodynamic and local magnetic field effects in the structural transition, which are not readily separable. However, an average of the Tm values agrees well with the value predicted from studies of the thermally induced transition made by optical methods. The values of J1'-2' for all six residues become very small (less than 1.5 Hz) at low temperatures indicating that C3'-endo is the most heavily populated furanose conformation in the helix. The sigma values of protons in the duplex were compared with those calculated from the ring current magnetic anisotropies of nearest and next-nearest neighboring bases using the geometrical parameters of the A'-RNA and B-DNA models. The sigma values of the base protons in the duplex calculated assuming the A'-RNA geometry agree (+/- approximately 0.1 ppm) with the observed values much more accurately than those calculated on the basis of B-DNA geometry. The measured sigma values of the H1' are not accurately predicted from either model. The synthesis of 35 mg of A2GCU2 using primer-dependent polynucleotide phosphorylase is described in detail with extensive discussion in the microfilm edition.
Damage of tissue culture cells (Hela, a human amnion, a primary rat liver culture) caused by the neodymium laser radiation was studied by time-lapse phase-contrast microfilming and electron microscopy. The tested cultures were shown to display different sensitivity and the degree of cell alteration within the same cultures varied considerably. A physical mechanism of cell damage is probably of thermal and shock-wave nature.
The objective quantitative evaluation of the extent of plaques is necessary for epidemiologic studies and for the estimation of the effects of various cleaning methods and agents. Numerous indices have been elaborated for this purpose. Relation planimetry is used for the detection and exact evaluation of small differences. The surfaces are measured with a compensating planimeter, the slides to be evaluated being projected on a white sheet by means of a microfilm reader. In this way, the plaque covered surfaces are determined as percentages of the total surfaces.
Vital microfilming revealed peculiarities of blood flow in microvessels of 2-5-micron diameter under relatively resting conditions, in normoxia, as well as the microcirculatory response to hypoxia (breathing with mixture of nitrogen and 6-8% oxygen for 5 min), in intact temporal muscle of rat. The average blood flow velocity in normoxia was 1.14 +/- 0.04 mm/sec in capillaries and 2.43 +/- 0.08 mm/sec in terminal arterioles. Breathing with the hypoxic mixture decelerated blood flow in 75% of the vessels. The blood low velocity in the muscle capillaries correlated with arterial blood pressure.
Characteristic features of conformational changes in chloroplasts have been studied by microfilm technique at BMI-13 installation. The oscillatory character of changes in chloroplast cross-section area in time, determined earlier by the tele-lazer microscopy technique, has been confirmed by our data. When chloroplasts are simultaneously seen in the microscope it is possible to observe their synchronous oscillation. The stationarity check of conformational changes shows that is a non-stationary process in the general case. So it is concluded that the standard technique of analysing accidental non-stationary processes can be used for study of conformational changes in chloroplasts provided that the corresponding parts of their kinetics are selected or trends are eliminated depending on the type of non-stationarity.
Color microfiche afford a low-cost method for providing students with a complete series of color illustrations depicting procedures to be performed in their preclinical laboratory exercises.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
An intelligent terminal has been used at a radiology reception desk to maintain a master patient index and to assist documentation. It also yields valuable management information.
Explore the source record for details and available documents.