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361.
The prevalence of urinary tract infections (UTIs) in cats with hyperthyroidism (n=90), diabetes mellitus (DM) (n=57) and chronic kidney disease (CKD) (n=77) was evaluated retrospectively. It was found to be 12% in cats with hyperthyroidism and DM, respectively, and 22% in cats with CKD. Associations between UTIs and clinical signs, biochemical markers in serum and urinalyses were investigated. Many of the cats with UTIs had no clinical signs of lower urinary tract disease or changes in their laboratory values indicative of infection. Therefore, a urinalysis alone should not be used to exclude UTIs in these cats. UTIs are relatively common in cats with hyperthyroidism, DM and CKD, and urine cultures are recommended as part of the basic diagnostic plan for cats suspected of suffering from these conditions. 相似文献
362.
363.
Stone RG Macdowall RJ Fainberg J Kaiser ML Desch MD Goldstein ML Hoang S Bougeret JL Harvey CC Manning R Steinberg JL Kellogg PJ Lin N Goetz K Osherovich VA Reiner MJ Canu P Cornilleau-Wehrlin N Lengyel-Frey D Thejappa G 《Science (New York, N.Y.)》1995,268(5213):1026-1029
Ulysses spacecraft radio and plasma wave observations indicate that some variations in the intensity and occurrence rate of electric and magnetic wave events are functions of heliographic latitude, distance from the sun, and phase of the solar cycle. At high heliographic latitudes, solartype Ill radio emissions did not descend to the local plasma frequency, in contrast to the emission frequencies of some bursts observed in the ecliptic. Short-duration bursts of electrostatic and electromagnetic waves were often found in association with depressions in magnetic field amplitude, known as magnetic holes. Extensive wave activity observed in magnetic clouds may exist because of unusually large electron-ion temperature ratios. The lower number of intense in situ wave events at high latitudes was likely due to the decreased variability of the high- latitude solar wind. 相似文献
364.
Incorporation of [(3)H]thymidine into nuclei of heart cells of 2-day-old rats indicates that neonatal cardiac cells containing well-aligned myofibrils synthesize DNA. In these highly differentiated cells, neither the presence of contractile proteins nor their organization into myofibrils inhibits either DNA synthesis or mitosis. 相似文献
365.
The LDL receptor gene: a mosaic of exons shared with different proteins 总被引:112,自引:0,他引:112
The multifunctional nature of coated pit receptors predicts that these proteins will contain multiple domains. To establish the genetic basis for these domains (LDL) receptor. This gene is more than 45 kilobases in length and contains 18 exons, most of which correlate with functional domains previously defined at the protein level. Thirteen of the 18 exons encode protein sequences that are homologous to sequences in other proteins: five of these exons encode a sequence similar to one in the C9 component of complement; three exons encode a sequence similar to a repeat sequence in the precursor for epidermal growth factor (EGF) and in three proteins of the blood clotting system (factor IX, factor X, and protein C); and five other exons encode nonrepeated sequences that are shared only with the EGF precursor. The LDL receptor appears to be a mosaic protein built up of exons shared with different proteins, and it therefore belongs to several supergene families. 相似文献
366.
T C Südhof D W Russell J L Goldstein M S Brown R Sanchez-Pescador G I Bell 《Science (New York, N.Y.)》1985,228(4701):893-895
The amino acid sequences of the human low-density lipoprotein (LDL) receptor and the human precursor for epidermal growth factor (EGF) show 33 percent identity over a stretch of 400 residues. This region of homologous is encoded by eight contiguous exons in each respective gene. Of the nine introns that separate these exons, five are located in identical positions in the two protein sequences. This finding suggests that the homologous region may have resulted from a duplication of an ancestral gene and that the two genes evolved further by recruitment of exons from other genes, which provided the specific functional domains of the LDL receptor and the EGF precursor. 相似文献
367.
Lanza RP Arrow KJ Axelrod J Baltimore D Benacerraf B Bloch KE Bloembergen N Brown HC Brown MS Cibelli JB Cohen S Cooper LN Corey EJ Dulbecco R Fischer EH Fitch VL Friedmen M Friedman M Furchgott RF Gell-Mann M Glaser DA Glashow SL Gilbert W Goldstein JL Wilson RW 《Science (New York, N.Y.)》1999,283(5409):1849-1850
368.
Deletion in cysteine-rich region of LDL receptor impedes transport to cell surface in WHHL rabbit 总被引:40,自引:0,他引:40
T Yamamoto R W Bishop M S Brown J L Goldstein D W Russell 《Science (New York, N.Y.)》1986,232(4755):1230-1237
The Watanabe heritable hyperlipidemic (WHHL) rabbit, an animal with familial hypercholesterolemia, produces a mutant receptor for plasma low-density lipoprotein (LDL) that is not transported to the cell surface at a normal rate. Cloning and sequencing of complementary DNA's from normal and WHHL rabbits, shows that this defect arises from an in-frame deletion of 12 nucleotides that eliminates four amino acids from the cysteine-rich ligand binding domain of the LDL receptor. A similar mutation, detected by S1 nuclease mapping of LDL receptor messenger RNA, occurred in a patient with familial hypercholesterolemia whose receptor also fails to be transported to the cell surface. These findings suggest that animal cells may have fail-safe mechanisms that prevent the surface expression of improperly folded proteins with unpaired or improperly bonded cysteine residues. 相似文献
369.
Fish mortality due to acute ammonia exposure 总被引:2,自引:0,他引:2
J. V. TARAZONA MJ. MUOZ J. A. ORTIZ MO. NUNÉZ J. A. CAMARGO 《Aquaculture Research》1987,18(2):167-172
Abstract. Fish mortality in the River Umia, near Villagarcia de Arosa, Pontevedra, Spain, which occurred after a discharge from a food sewage works, is studied. Physico-chemical parameters of water samples from sewage and from the River Umia were studied and concentrations of ammonia sufficiently high to cause toxic effects in fish (702 mg/1 and 302 mg/1 as total ammonia) were found. The toxicity of two concentrations of ammonia was investigated on goldfish, Carassius auratus (L.), using water quality values the same as found in the River Umia, to obtain the same concentrations of un-ionized ammonia (2·13 mg/1 and 0·91 mg/1). Fish exposed to high concentrations died within 24 h and three of six, which were exposed to the lowest concentration died within 96h. All fish at first showed symptoms of hyper excitability and hyperventilation, and at times of rest showed a decrease in respiration. Post-mortem findings generally included gill congestion and haemorrhage. 相似文献
370.
Hendrik IJ Roest Jacob Post Betty van Gelderen Fred G van Zijderveld Johanna MJ Rebel 《Veterinary research》2013,44(1):67
Q fever is a zoonosis caused by the intracellular bacterium Coxiella burnetii. Both humoral and cellular immunity are important in the host defence against intracellular bacteria. Little is known about the immune response to C. burnetii infections in domestic ruminants even though these species are the major source of Q fever in humans. To investigate the goat’s immune response we inoculated groups of pregnant goats via inhalation with a Dutch outbreak isolate of C. burnetii. All animals were successfully infected. Phase 1 and Phase 2 IgM- and IgG-specific antibodies were measured. Cellular immune responses were investigated by interferon-gamma, enzyme-linked immunosorbent spot test (IFN-γ Elispot), lymphocyte proliferation test (LPT) and systemic cytokines. After two weeks post inoculation (wpi), a strong anti-C. burnetii Phase 2 IgM and IgG antibody response was observed while the increase in IgM anti-Phase 1 antibodies was less pronounced. IgG anti-Phase 1 antibodies started to rise at 6 wpi. Cellular immune responses were observed after parturition. Our results demonstrated humoral and cellular immune responses to C. burnetii infection in pregnant goats. Cell-mediated immune responses did not differ enough to distinguish between Coxiella-infected and non-infected pregnant animals, whereas a strong-phase specific antibody response is detected after 2 wpi. This humoral immune response may be useful in the early detection of C. burnetii-infected pregnant goats. 相似文献