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91.
Nutrition and cancer. Recent developments   总被引:1,自引:0,他引:1  
Cancer cachexia is a complex syndrome that results in involuntary weight loss, even in the face of adequate nutritional intake. The profound metabolic abnormalities associated with cancer cachexia affect a large percentage of animals with cancer even before any clinical signs are seen. This paraneoplastic syndrome results in alterations in carbohydrate, lipid, and protein metabolism that, if left untreated, decrease the animal's quality of life and lead to a poor response to cancer therapy. An understanding of the metabolic abnormalities associated with cancer cachexia is of paramount importance to the practicing veterinarian to determine an accurate prognosis and to choose the optimal type of intravenous fluids and nutritional therapy for each patient. Although research identifying the optimal diet for cancer-bearing dogs and cats is still underway, some general principles apply. The first is that the patient should receive nutritional elements orally whenever possible. When oral feeding is not possible, nasogastric, gastrostomy, and jejunostomy tube feeding are viable options. When feeding by the gastrointestinal tract is not possible, parenteral feeding is a practical alternative.  相似文献   
92.
Nine dogs with intermediate- or high-grade lymphoma were prospectively entered into a protocol to be given a total of 15 weekly doses of doxorubicin (10 mg/m2 of body surface, IV) in an attempt to eliminate all clinical evidence of neoplasia, with minimal risk of drug toxicity. Eight of these dogs did not complete the protocol because of progression of the disease. The median number of doses administered to dogs that developed progressive disease before the regimen was completed was 5 (range, 2 to 9). Seven dogs achieved partial (n = 5) or complete (n = 2) remission, with median duration of 14 days (range, 7 to 231 days). The dog that was given all 15 weekly treatments remained in complete remission for 231 days. Complete remission that lasted for 14 days was observed in another dog. Toxicosis developed in 3 dogs; signs of toxicosis were generally mild and included colitis (n = 1), vomiting (n = 1), neutropenia (n = 1), and lethargy (n = 1). The lowest neutrophil count (1,876 cells/microliter) was seen in one dog after 7 doses of doxorubicin were given. Doxorubicin at dosage of 10 mg/m2/wk appears to be safe, but is generally ineffective for treatment of lymphoma.  相似文献   
93.
One hundred twenty-nine dogs with histologically confirmed malignant tumors were used in a prospective study to determine the toxicity of the new dihydroxyquinone derivative of anthracene, mitoxantrone, which was administered IV at 21-day intervals at dosages ranging from 2.5 to 5 mg/m2 body surface area. Each dog was evaluated for signs of toxicosis for 3 weeks after each dose was administered or until the dog died, whichever came first. The number of dogs in each evaluation period were as follows: 1 dose (n = 129), 2 doses (n = 82), 3 doses (n = 43), 4 doses (n = 26), 5 doses (n = 19), 6 doses (n = 9), 7 doses (n = 6), 8 doses (n = 5), 9 doses (n = 3), and 10 doses (n = 1). The most common signs of toxicosis were vomiting, diarrhea, anorexia, and sepsis secondary to myelosuppression. None of the dogs died of complications resulting from mitoxantrone treatment. Dogs with signs of toxicosis during the 21-day interval from administration of the first dose of mitoxantrone were 95 times (P = 0.003) more likely to develop signs of toxicosis during the 21-day interval from the second dose of mitoxantrone. Similarly, dogs that developed signs of toxicosis during the 21-day interval from the administration of the second dose were 34 times (P less than 0.001) more likely to develop signs of toxicosis during the 21-day interval from the administration of the third dose. With each 1 mg/m2 increase in mitoxantrone, the odds of developing signs of toxicosis increased by 5.9 fold (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
94.
95.
The aim of this study was to determine the association between the oestrous response of pre‐pubertal gilts to gonadotrophin injection or boar exposure and their subsequent farrowing rate and litter size. At 154 days of age, randomly selected pre‐pubertal gilts received an intramuscular injection of 400 IU equine chorionic gonadotrophin plus 200 IU human chorionic gonadotrophin (PG600®; Merck Animal Health; n = 181). From the remaining pool of animals not treated with hormones, the first gilts showing signs of oestrus were selected to act as controls (n = 201). Boar exposure began at 155 days of age for both groups, and gilts were bred at a weight of approximately 130 kg. Comparisons were made between PG600®‐treated gilts exhibiting oestrus or not within 7 days post‐injection (early and late responders, respectively) and control gilts exhibiting oestrus or not within 30 days after beginning of boar exposure (select and non‐select control gilts, respectively). By 162 days, oestrus was detected in 67.5% of PG600®‐treated gilts compared with 5.7% of control gilts (p < 0.0001). The proportion of animals observed in oestrus at least three times before breeding was greater for select control gilts compared with early and late responder PG600®‐treated gilts (p  0.001). There were no significant differences in farrowing rate and litter size between the four treatment groups. These data indicate that PG600® is an effective tool to induce an earlier oestrus in gilts, that subsequent farrowing rate and born alive litter size compare favourably to that of select gilts and that gilts failing to respond promptly to hormonal stimulation do not exhibit compromised fertility.  相似文献   
96.
Growth and yield responses of developing almond trees (Prunus amygdalus, Ruby cultivar) to a range of trickle irrigation amounts were determined in 1985 through 1987 (the fifth through seventh year after planting) at the University of California's West Side Field Station in the semi-arid San Joaquin Valley. The treatments consisted of six levels of irrigation, ranging from 50 through 175% of the estimated crop evapotranspiration (ETc), applied to a clean-cultivated orchard using a line source trickle irrigation system with 6 emitters per tree. ETc was estimated as grass reference evapotranspiration (ET0) times a crop coefficient with adjustments based upon shaded area of trees and period during the growing season. Differential irrigation experiments prior to 1984 on the trees used in this study significantly influenced the initial trunk cross-section area and canopy size in the 50% ETc treatment and 125% ETc treatment. In these cases, treatment effects must be identified as relative effects rather than absolute. The soil of the experimental field was a Panoche clay loam (nonacid, thermic, Typic Torriorthents). The mean increase in trunk cross-sectional area for the 3-year period was a positive linear function (r 2 = 0.98) of total amounts of applied water. With increases in water application above the 50% ETc treatment, nut retention with respect to flower and fertile nut counts after flowering, was increased approximately 10%. In 1985 and 1987, the nut meat yields and mean kernel weights increased significantly with increasing water application from 50% to 150% ETc. Particularly in the higher water application treatments, crop consumptive use was difficult to quantify due to uncertainty in estimates of deep percolation and soil water uptake. Maintenance of leaf water potentials higher than –2.3 MPa during early nut development (March through May) and greater than –2.5 MPa the remainder of the irrigation season (through August) were positively correlated with sustained higher vegetative growth rates and higher nut yields.  相似文献   
97.
Long term use of saline water for irrigation   总被引:1,自引:0,他引:1  
Use of saline drainage water in irrigated agriculture, as a means of its disposal, was evaluated on a 60 ha site on the west side of the San Joaquin Valley. In the drip irrigation treatments, 50 to 59% of the irrigation water applied during the six-year rotation was saline with an ECw ranging from 7 to 8 dS/m, and containing 5 to 7 mg/L boron and 220 to 310 g/L total selenium. Low salinity water with an ECw of 0.4 to 0.5 dS/m and B 0.4 mg/1 was used to irrigate the furrow plots from 1982 to 1985 after which a blend of good quality water and saline drainage water was used. A six-year rotation of cotton, cotton, cotton, wheat, sugar beet and cotton was used. While the cotton and sugar beet yields were not affected during the initial six years, the levels of boron (B) in the soil became quite high and were accumulated in plant tissue to near toxic levels. During the six year period, for treatments surface irrigated with saline drainage water or a blend of saline and low salinity water, the B concentration in the soil increased throughout the 1.5 m soil profile while the electrical conductivity (ECe) increased primarily in the upper l m of the profile. Increaszs in soil ECe during the entire rotation occurred on plots where minimal leaching was practiced. Potential problems with germination and seedling establishment associated with increased surface soil salinity were avoided by leaching with rainfall and low-salinity pre-plant irrigations of 150 mm or more. Accumulation of boron and selenium poses a major threat to the sustainability of agriculture if drainage volumes are to be reduced by using drainage water for irrigation. This is particularly true in areas where toxic materials (salt, boron, other toxic minor elements) cannot be removed from the irrigated area. Continual storage within the root zone of the cropped soil is not sustainable.  相似文献   
98.
The electrical resistance of wires consisting of either a single xenon atom or two xenon atoms in series was measured and calculated on the basis of an atom-jellium model. Both the measurement and the calculation yielded a resistance of 10(5) ohms for the single-xenon atom system and 10(7) ohms for the two-xenon atom system. These resistances greatly exceeded the 12,900-ohm resistance of an ideal one-dimensional conduction channel because conduction through the xenon atoms occurs through the tail of the xenon 6s resonance, which lies far above the Fermi level. This conduction process in an atom-sized system can now be understood in terms of the electronic states of individual atoms.  相似文献   
99.
100.
MLN4924 (pevonedistat) is a potent and selective NEDD8‐activating enzyme (NAE) inhibitor. The NEDD8‐regulated neddylation system is responsible for the regulated degradation of intracellular proteins with important cellular functions in cancer cell growth, apoptosis, angiogenesis and metastasis. In human melanoma, inhibition of NAE results in induction of DNA re‐replication, S phase cell cycle arrest, DNA damage and apoptosis. The study aimed to assess the anti‐cancer effect of MLN4924 on canine malignant melanoma cell lines and patient samples and to elucidate the underlying mechanisms. Canine melanoma cell lines and primary patient samples were evaluated for cell viability after incubation with varying concentrations of MLN4924 or dimethyl sulfoxide. Apoptosis, cell proliferation and senescence assays were performed to address underlying mechanisms of MLN4924‐mediated anti‐tumour effects. Gene expression of seven previously identified deregulated genes in human melanoma was compared in sensitive vs resistant samples. MLN4924 treatment significantly reduced the viability of canine melanoma cell lines and primary samples in a dose‐ and time‐dependent manners. MLN4924 promoted cell apoptosis and inhibited cell growth through induction of DNA re‐replication and cell senescence. While the majority of canine melanoma samples demonstrated sensitivity at nanomolar ranges, some samples were resistant to the treatment. Modulation of P21 levels correlated with canine melanoma cell sensitivity. These results provided justification for further exploration of MLN4924 as a treatment of canine melanoma.  相似文献   
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