Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    World journal of urology 9 (1991), S. 69-74 
    ISSN: 1433-8726
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neoplasia is the result of cumulative genetic damage. Cytogenetic analysis identifies abnormalities of chromosome number and structure. Abnormal mode, wide variation in chromosome number, and aneuploidy are associated with loss of differentiation and advanced stage in bladder cancer. Marker chromosomes have been associated with increased risk of recurrence and progression of superficial, low-grade tumors. With the use of banding techniques, aberrations can be assigned to specific chromosomes and significant nonrandom abnormalities have been identified on chromosomes 1, 3, 5, 7, 9, 11, and 17. With the use of molecular biology techniques, allelic deletions, proto-oncogene activation, and mutations can be detected and correlated to the pathophysiologic events that determine the biologic behavior of a particular tumor. Allelic deletions of chromosome 9q are independent of stage and grade and suggest that loss of a tumor suppressor gene on chromosome 9q may be an important primary event in the genesis of bladder cancer. Deletions of chromosomes 11p and 17p, evident only in high-grade tumors, may be important in bladder cancer progression.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1619-6937
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary Fracture of a hybrid laminate containing a pair of collinear cracks in the central layer is studied. The surfaces of the cracks are opened by an arbitrary opening pressure. The problem is reduced to the solution of the Fredholm integral equation of the second kind by using the techniques of the Fourier transforms and the finite Hilbert transform. In the case of an uniform opening pressure, the exact expressions for the stress intensity factors in the inner tip and the outer tip of the cracks and the shape of the deformed crack are obtained. Numerical calculations are carried out to study the interaction between the cracks and the effects of the hybrid lamination on the fracture of the hybrid laminate.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The newly recruited Japanese eel, Anguilla japonica, elvers and 1-year-old eels collected in estuaries and in rivers, respectively, were studied. The microstructure and chemical composition of the sagittal otolith of these eels were examined by SEM and wavelength-dispersive spectrometer (WDS), A transition zone or‘elver mark’was observed in the otolith of the young eels. A comparison of the otoliths of elvers with those from the 1-year-old eels suggests that this transition zone was deposited during upstream migration, a change from a marine to freshwater environment. Strontium (Sr) content in the primordium of the otolith of both elvers and young eels was low, probably due to the maternal or freshwater origin of the oocyte. The concentration of Sr in the otolith increased gradually during marine life and reached a peak approximately 1 month before upstream migration. As the elvers entered the estuary, the Src concentration dramatically decreased and remained at a low level thereafter. These findings indicate that the history of the migratory environment of the eel can be reconstructed from a combined study of otolith microstructure and microchemistry analysis.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: To test the hypothesis that the Japanese eel, Anguillu japonica, elvers in the eastern and western coasts of Taiwan are recruited from two different spawning grounds and to increase the knowledge of the early life history of the eel, the otolith microstructure and daily age of elvers collected from five estuaries in the coast of Taiwan during December 1989 through February 1990 were examined by scanning electron microscopy. The total length of elvers at arrival in the estuaries was similar among estuaries, averaging c. 56.0 mm and showed a seasonal decrease. The maximum radius of the sagittal otolith of elvers ranged from 124.46 to 181.82μm with a mean of 143.15 ± 12.72 μm. The otolith from centre to edge included an organic-rich primordium (9.20 ± 2.02 μm in diameter), a diffusively calcified core (20.94 ± 1.99 μm), and the daily growth increments; these three layers were probably deposited during the embryonic, yolk sac and feeding period respectively. The growth rate of the otolith was higher at the beginning of early life (0.5−1.0 μm day −1), lowest at approximately 100-days old (〈0.5 μm day−1), and highest 1 month before arrival at the estuary (〉 1.0 pm day−1). The mean age for elvers arriving in the estuaries of the coasts of Taiwan was approximately 170.4 ± 21.02 days. Neither the growth pattern of the otolith nor the age of elvers arriving in the estuary were significantly different among estuaries, indicating that the elvers in both eastern and western Taiwan were probably recruited from the same spawning ground. The growth pattern of the otolith in relation to larval migration was analysed.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 15 (1992), S. 0 
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Mesophyll protoplasts from Brassica oleracea, B. napus, Nicotiana tobaccum and Solanum tuberosum were isolated and subjected to uttracentrifugation at 65000g for 30 min in percoll solutions containing various strengths of salt and osmotic stabilizing agents. After centrifugation, the self-generated percoll gradients were evaluated for their effectiveness in protoplast evacuolation and enucleation. The vacuoles, cell debris, evacuolated protoplasts and enucleated protoplasts were separated. Factors that affected evacuolation and enucleation in the percoll gradients were described. Mesophyll protoplasts produced by epidermis peeling and short enzyme incubation periods were more easily evacuolated and enucleated than those produced by leaf-slicing and long incubation periods. Lower centrifugal force at 25000g for 80 min was also successful in evacuolating and enucleating the mesophyll protoplasts. A green band that contained nearly pure evacuolated protoplasts, of which 45% were enucleated protoplasts, was obtained from the self-generated percoll gradient. Rhodamine 123 staining of mitochondria indicated that the evacuolated protoplasts were metabolically active and were capable of regenerating the vacuole and cell wall. Cell divisions were also observed when the evacuolated protoplasts were cultured.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 54 (1994), S. 1773-1779 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 39 (1992), S. 1128-1132 
    ISSN: 0006-3592
    Keywords: lipolytic rates ; hydrolysis ; tributyrin ; Candida rugosa ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A dramatic change of the reaction rate was observed for the lipase-catalyzed hyrolysis of tributyrin in a batch reactor. Immediately after the addition of the enzyme, the lipolysis rate increased continuously until a maximal reaction rate was reached. The duration of the induction was mainly controlled by the bulk enzyme concentration and the reactor stirring speed. The reaction rate dropped sharply after reaching its maximal value. The lipolysis decayed at a rate of about 0.012 min-1, and was not affected by changes of the stirring speed. This decay was attributed to the fast deactivation of the surface-adsorbed lipase, and possibly to the extremely slow desorption of the inactivated species. For reaction time longer than 120 minutes, the lipolysis decreased at a much slower rate. Several mechanisms for the decay of the lipolysis rate were discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of arsenic (As2O3) on plasma osmolarity, Na and K concentrations, the activity of gill Na−K-ATPase, and on the ultrastructure of gill chloride cells were compared between seawater tilapia (Oreochromis mossambicus) and freshwater tilapia in the Institute of Zoology, Academia Sinica, between 1989 and 1991. Arsenic was found to be more lethal in seawater tilapia [96 h LC50 (median lethal concentration): 26.5 ppm] than in freshwater ones (71.7 ppm). No significant effect was found on plasma ion concentrations and osmolarity, enzyme activity or the ultrastructure of chloride cells in freshwater tilapia after 96 h exposure to 70 ppm arsenic. In contrast, 96 h exposure to 15 ppm arsenic caused evident effects in seawater tilapia: an increase in plasma osmolarity and activity of gill Na−K-ATPase, as well as better development of the chloride cell tubular system. These data suggest that the lethal effect of arsenic may be partially attributed to a hydromineral disturbance in seawater tilapia, but in freshwater tilapia arsenic perhaps causes destruction in some physiological mechanisms other than osmoregulation. The activation of gill Na−K-ATPase and chloride cells in seawater tilapia appears to indicate an adaptation in the osmoregulatory mechanism to arsenic exposure, i.e., to enhance secreting ions or arsenic in the gills.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1572-9559
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1572-9338
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract This paper describes the design and implementation of the prototype structured modeling environment FW/SM. The underlying design principles provide the central focus. Other points of interest include discussions of FW/SM's delivery platform, its interface to external packages, and its optimization interfaces. The intended audience is all modeling system evaluators, designers, and implementors, including those who do not happen to take a structured modeling approach.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...