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81.
PATMAT: a searching and extraction program for sequence, pattern and block queries and databases 总被引:2,自引:0,他引:2
A program has been developed that provides molecular biologistswith multiple tools for searching databases, yet uses a verysimple interface. PATMATcan use protein or (translated) DNAsequences, patterns or blocks of aligned proteins as queriesof databases consisting of amino acid or nucleotide sequences,patterns or blocks. The ability to search databases of blocksby on-the-fly conversion to scoring matrices providesa new tool for detection and evaluation of distant relationships.PATMAT uses a pull-down, menu-driven interface to carry outits multiple searching, extraction and viewing functions. Eachquery or database type is recognized, reported, and the appropriatesearch carried out, with matches and alignments reported inwindows as they occur. Any of the high scoring matches can beexported to a file, viewed and recalled as a query using onlya few keystrokes or mouse selections. Searches of multiple databasefiles are carried out by user selection within a window. PATMATruns under DOS; the searching engine also runs under UNIX. 相似文献
82.
Twelve strains ofLegionella pneumophila were tested for the presence of plasmid DNA. Three strains, belonging to serogroup 1, had large plasmids of 83.8×106 daltons, as determined by electron microscopy. A fourth strain, also from serogroup 1, had a similar large plasmid in addition to a smaller plasmid. Restriction analysis of plasmid DNA isolated from the strains with a single size plasmid indicated that the plasmids were structurally very similar. The biologic functions of these plasmids are yet to be determined. 相似文献
83.
Dr. Edward B. Blanchard Frank Andrasik Susan E. Jurish Steven J. Teders 《Applied psychophysiology and biofeedback》1982,7(2):185-191
Eleven patients with episodic cluster headache were assessed and offered a treatment program consisting of 8 weeks of training in abbreviated progressive relaxation followed by 12 sessions of thermal biofeedback. Four dropped out before treatment began. Of the seven who completed the full treatment regimen, three (27% of initial sample) reported some degree of improvement when their next cluster bout occurred. In no one was the disorder eliminated.This research was supported by a grant from the National Institute of Neurological and Communicative Disorders and Stroke, NS-15235. 相似文献
84.
85.
Steven Martindale 《Journal of theoretical biology》1980,83(1):107-110
In a recent paper in this journal, Sparling & Williams (1978) demonstrated several multivariate techniques by applying them to measurements of albatross calls. Their paper contains a useful summary of the literature, but includes several misleading interpretations of the analyses. Since the stated purpose of that article was to familiarize biologists with proper uses of the statistical methods, it is important to clarify the problems, some of which I discuss below. I then mention how such techniques are likely to be particularly valuable in the near future, when coupled with real-time sound spectrum analysis. 相似文献
86.
Three methods of estimating bacterial productivity were compared using parallel samples of Atlantic Ocean water (within 0.25–15 km of the Georgia coast). The frequency-of-dividing cells (FDC) method and the [3H]thymidine incorporation method gave results which were strongly correlated (r=0.97), but the FDC estimates were always higher (X2 to X7) than the [3H]thymidine estimates. Estimates of bacterial productivity ranged from 2–4×108 cells·l–1·h–1 at 0.25 km from shore to 1–9×107cells·l–1·h–1 at 15 km. A method involving incubation of 3-m filtrates and direct counting gave results that could not be easily translated into estimates of bacterial productivity. Application of the FDC method to sediment samples gave high productivity estimates, which could be not reconciled with productivity estimates based on sediment oxygen uptake. 相似文献
87.
Analysis of the nucleoside triphosphate pyrophosphohydrolase specific activity of red cells obtained from a random Caucasian population indicated at least two subclasses. The specific activity of 18% of the population ranged from undetectable activity to 27.5 nmol ITP cleaved/20 min/mg hemoglobin. The remainder of the population had higher activity, 27.5–125 nmoles ITP cleaved/20 min/mg hemoglobin. The variation of NTPH activity evident in the red cells of an individual is reflected in granulocytes, lymphocytes, and platelets of that individual. Erythrocyte activity ranges from 0.7 to 21 units (nmol of ITP cleaved in 20 min)/107 cells, granulocytes have 17–201 units/107 cells, lymphocytes have 91–462 units/107 cells, and platelets have 1.1–7.1 units/107 platelets. These cell differences are discussed with respect to the hypothesis that NTPH prevents incorporation of ITP or dITP into nucleic acids.This work was supported by funds allocated by the Agricultural Experiment Station, Michigan State University. Michigan Agricultural Experiment Station Journal No. 8727. 相似文献
88.
R. B. Cumming Marva F. Walton J. C. Fuscoe B. A. Taylor J. E. Womack F. H. Gaertner 《Biochemical genetics》1979,17(5-6):415-431
A single formamidase, which is different from the formamidases found in other tissues, occurs in the brains of mice. This enzyme is here called formamidase-5 and the gene symbol is designated For-5. Two alleles are recognized on the basis of their differential heat sensitivity: For-5
b is relatively heat stable and is present in strain C57BL/6J, while For-5
d is relatively heat sensitive and is present in strain DBA/2J. The heat sensitivity of formamidase-5 in 44 other inbred strains and substrains was tested and found to resemble that of C57BL/6J or DBA/2J. Thirty-six recombinant inbred strains derived from progenitors that differed at For-5 were studied to test for single-gene inheritance and linkage with other loci. Complete concordance was found with the esterase-10 locus (Es-10), indicating close linkage. The 99% upper confidence limit of the distance between For-5 and Es-10 is 3.7 centimorgans (cM). Es-10 is located on chromosome 14 about 19 cM from the centromere. An independent demonstration of linkage of For-5 with Es-10 and another chromosome 14 marker, hairless (hr), is provided by the finding that the HRS/J strain, which has been sibmated for 60 generations with forced heterozygosity at the hr locus, is cosegregating at For-5 and Es-10. A survey of 32 inbred strains and substrains revealed that the For-5
d allele is associated with the Es-10
b allele, and that the For-5
b allele is associated with Es-10
a and Es-10
c. Formamidase-5 segregates as expected in the F2 generation of crosses between strains bearing For-5
b and For-5
d alleles. It is possible that this unique formamidase of the brain is involved in the metabolism of a neurotransmitter substance.This research was sponsored in part by the Department of Energy under contract with the Union Carbide Corporation and in part by NIH Research Grant GM-18684 from the National Institute of General Medical Sciences. J. C. F. is a predoctoral Fellow supported by Grant CA 09104 from the National Cancer Institute. The Biology Division of Oak Ridge National Laboratory and the Jackson Laboratory are fully accredited by the American Association for Accreditation of Laboratory Animal Care. 相似文献
89.
90.
C Isles J J Brown A M M Cumming A F Lever D McAreavey J I S Robertson V M Hawthorne G M Stewart J W K Robertson J Wapshaw 《BMJ (Clinical research ed.)》1979,1(6163):579-581
The smoking habits of 82 patients with malignant-phase hypertension were compared with those of subjects in three control groups matched for age and sex. Sixty-seven (82%) of the patients with malignant-phase hypertension were smokers compared with 41 (50%) and 71 (43%) of the patients in two control groups with non-malignant hypertension, and 43 people (52%) in a general population survey. The excess of smokers in the malignant-phase group was significant for men and women, together and separately, for cigarette smoking alone, and for all forms of smoking. There were no significant differences between the control groups. The chance of a hypertensive patient who smoked having the malignant phase was five times that of a hypertensive patient who did not. Twelve patients in the malignant-phase group had never smoked. All were alive three and a half years on average after presentation (range 11 months to seven years). Twenty-four (36%) of the smokers with malignant-phase hypertension died during the same period. The mortality rate was significantly higher among patients with renal failure, as was the prevalence of smoking. Eighteen patients with malignant-phase hypertension had a serum creatinine concentration higher than 250 μmol/l (2·8 mg/100 ml); 17 were smokers and one an ex-smoker. Eleven of these 18 patients died.It is concluded that hypertensive patients who smoke are much more likely to develop the malignant phase than those who do not, and that once the condition has developed it follows a particularly lethal course in smokers. 相似文献