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51.
We hypothesised that analgesia of the navicular bursa is not selective for the navicular apparatus; and that solar pain in some horses can be temporarily abolished or attenuated by analgesia of the navicular bursa. To test this hypothesis, we caused lameness in horses by inducing pain in the dorsal margin or the angles of the sole and then evaluated the ability of a local analgesic solution administered into the navicular bursa to attenuate lameness. The response of horses with solar pain in the dorsal or palmar aspect of the foot to 3.5 ml local analgesic solution administered into the navicular bursa was examined. Lameness was induced in 6 horses by creating solar pain in the dorsal aspect of one forefoot and, at another time, the palmar aspect of the other forefoot, with set-screws inserted into a custom-made shoe. Horses were videotaped trotting before and after application of set-screws and after administering 3.5 ml local analgesic solution into the navicular bursa. Lameness scores were assigned by examining videotaped gaits. Scores were significantly lower (P<0.05) for all horses with set-screws applied to the dorsal margin of the sole after administration of local analgesic solution into the navicular bursa. In conclusion, analgesia of the navicular bursa was less effective in desensitising the angles of the sole than in desensitising the dorsal margin of the sole. Pain arising from the sole should not be excluded as a cause of lameness when lameness is attenuated by analgesia of the navicular bursa.  相似文献   
52.
Red blood cells (RBC) become sensitized following the elution of strain 575 Newcastle disease virus (NDV). The neuraminidase (NA) in the haemagglutinin (HA)-sialic acid configuration is inactive. The HA on sensitized RBC agglutinates normal RBC. The sialic acid on normal RBC initiated reactivation of the NA-a newly described function. Then normal-sensitized RBC agglomerates separated at 37 degrees C in the irreversible agglutination-separation (AS) reactions. With separation the AS products. HN spikes (150-200 kDa) and altered NDV, which contain fewer HN spikes than intact allantoic NDV, were removed from the sensitized RBC and the NDV membrane. Extraction of HN spikes from the membrane required more sialic acid than the removal of AS products from RBC. Thus 2 reactions were delineated for the orderly removal. Amounts of each released AS product suggest the source of the HN spikes. AS reactions and ether treatment of NDV increased the HA titres up to 19.2 fold. HA-sialic acid configurations were estimated by the amounts of normal RBC agglutinated by sensitized RBC and also by agglutination with fetuin. Elution of B1 vaccine, HN spikes from ether-treated NDV as well as AS products separated on sephadex resulted in incompletely sensitized RBC; fewer configurations were titrated with normal RBC; all failed to respond to anti-NA antibody. In contrast, sensitized RBC or suspensions of 575 NDV, but not the B1 vaccine strain, responded to both anti-NA and anti-HA antibody. Sensitization, slow elution, and responding to anti-NA antibody, which was accompanied by fluorescent foci on sensitized RBC, required intact NDV and the infrequent HA-sialic acid configuration. The NA was inactive for the HA-sialic acid configuration but cleaved fetuin, indicating substrate specificity. An inactive NA would allow time for fusion and NDV penetration rather than elution by an active NA early in NDV infection.  相似文献   
53.

Context

Current production from natural forests will not satisfy future world demand for timber and fuel wood, and new land management options are required.

Aims

We explore an innovative production system that combines the production of short rotation coppice in wide alleys with the production of high-value trees on narrow strips of land; it is an alternative form of alley cropping which we propose to call ‘alley coppice’. The aim is to describe this alley coppice system and to illustrate its potential for producing two diverse products, namely high-value timber and energy wood on the same land unit.

Methods

Based on a comprehensive literature review, we compare the advantages and disadvantages of the alley coppice system and contrast the features with well-known existing or past systems of biomass and wood production.

Results

We describe and discuss the basic aspects of alley coppice, its design and dynamics, the processes of competition and facilitation, issues of ecology, and areas that are open for future research.

Conclusion

Based on existing knowledge, a solid foundation for the implementation of alley coppice on suitable land is presented, and the high potential of this system could be shown.  相似文献   
54.
A high-gain harmonic-generation free-electron laser is demonstrated. Our approach uses a laser-seeded free-electron laser to produce amplified, longitudinally coherent, Fourier transform-limited output at a harmonic of the seed laser. A seed carbon dioxide laser at a wavelength of 10.6 micrometers produced saturated, amplified free-electron laser output at the second-harmonic wavelength, 5.3 micrometers. The experiment verifies the theoretical foundation for the technique and prepares the way for the application of this technique in the vacuum ultraviolet region of the spectrum, with the ultimate goal of extending the approach to provide an intense, highly coherent source of hard x-rays.  相似文献   
55.
Identification of monocyte chemotactic activity produced by malignant cells   总被引:29,自引:0,他引:29  
Human malignant cells secrete low molecular size proteins that attract peripheral blood monocytes and may be responsible for the accumulation of tumor-associated macrophages observed in vivo. Similar chemotactic proteins are secreted by cultured vascular smooth muscle cells. The predominant monocyte chemoattractants produced by tumor cells of differing origin were demonstrated to be related to smooth muscle cell-derived chemotactic factor. Thus, a single class of chemotactic proteins is produced by different cell types, which suggests a common mechanism for the recruitment of monocytes and macrophages. These results are significant in view of the potential of macrophages to affect tumor growth.  相似文献   
56.
Incretin hormones are secreted from the intestines in response to specific nutrients. They potentiate insulin secretion and have other beneficial effects in glucose homeostasis. We aimed to study the incretin effect in cats and to compare the effect of oral glucose, lipids, or amino acids on serum concentrations of insulin, total glucose-dependent insulinotropic peptide (GIP) and total glucagon-like peptide 1 (GLP-1). Ten healthy cats were used in a repeated measures design. Glucose, lipid, or amino acids were administered through nasoesophageal tubes on separate days. Blood glucose (BG) concentrations were matched between experiments by measuring BG every 5 min and infusing glucose intravenously at a changing rate. Intravenous glucose infusion with no prior treatment served as control. The incretin effect was estimated as the difference in insulin area under the curve (AUC) after oral compared with intravenous glucose. Temporal changes and total amount of hormone secretions were compared between treatment groups with the use of mixed models. Total glucose infused (TGI) at a mean dose of 0.49 g/kg resulted in slightly higher BG compared with 1 g/kg oral glucose (P = 0.038), but insulin concentrations were not significantly different (P = 0.367). BG and the TGI were not significantly different after the 3 oral challenges. Total GIP AUC was larger after lipids compared with amino acids (P = 0.0012) but GIP concentrations did not increase after oral glucose. Insulin and GIP concentrations were positively correlated after lipid (P < 0.001) and amino acids (P < 0.001) stimulations, respectively, but not after oral glucose stimulation. Total GLP-1 AUC was similar after all three oral stimulations. Insulin and GLP-1 concentrations were positively correlated after glucose (P = 0.001), amino acids (P < 0.001), or lipids (P = 0.001) stimulations. Our data indirectly support an insulinotropic effect of GIP and GLP-1. Potentiation of insulin secretion after oral glucose is minimal in cats and is mediated by GLP-1 but not GIP.  相似文献   
57.
Although veterinary clinicians commonly rely on panels of laboratory tests with individual results flagged when abnormal, care should be taken in interpreting normal test results as well. There are several examples of this in evaluating patients with endocrine disease. The finding of a normal leukogram (absence of a stress leukogram) can be indicative of adrenal insufficiency in dogs, and this disorder can be especially elusive when there are no overt indicators of mineralocorticoid deficiency. Cats with hyperthyroidism can have normal serum thyroid hormone concentrations, normal hematocrits, and normal serum concentrations of creatinine despite the presence of disease that affects these parameters. A normal serum phosphorus concentration, in the face of azotemia, isosthenuria, and hypertension can point a clinician toward a diagnosis of primary hyperaldosteronism rather than primary renal disease. A normal serum parathyroid hormone concentration in the face of hypercalcemia is inappropriate and can indicate the presence of primary hyperparathyroidism. Similarly, hypoglycemia accompanied by a normal serum insulin concentration can be found in cases of hyperinsulinism. These normal findings in abnormal patients, and their mechanisms, are reviewed.  相似文献   
58.
Hypertension in Cats With Chronic Renal Failure or Hyperthyroidism   总被引:6,自引:0,他引:6  
The Doppler ultrasonic recording technique was used to measure systolic and diastolic blood pressures indirectly in 28 cats with naturally occurring renal failure, 39 cats with hyperthyroidism, and 33 clinically normal cats. The mean systolic and diastolic blood pressures in the normal cats were 118.4 +/- 10.6 mm Hg and 83.8 +/- 12.2 mm Hg, respectively. In the cats with chronic renal failure, both the systolic (146.6 +/- 25.4 mm Hg) and diastolic (96.6 +/- 15.2 mm Hg) blood pressures were significantly higher (P less than 0.0001 and P less than 0.01, respectively) than in the normal cats. Elevations in systolic and/or diastolic blood pressure were recorded in 17 (61%) of the 28 cats with chronic renal failure. In the 39 untreated hyperthyroid cats, both the mean systolic (167.9 +/- 28.9 mm Hg) and diastolic (111.6 +/- 21.5 mm Hg) pressures also were significantly higher (P less than 0.0001) than normal. Increased systolic and/or diastolic blood pressure was recorded in 34 (87%) of the 39 hyperthyroid cats. In seven cats with hyperthyroidism that were reevaluated two to four months after successful treatment of the hyperthyroid state, there was a significant fall in mean systolic pressure (P less than 0.05) from a pretreatment value of 159.5 +/- 15.4 mm Hg to a posttreatment value of 132.0 +/- 1.62 mm Hg. Overall, the results of this study indicate that mild to moderate hypertension is common in cats with chronic renal failure and in cats with untreated hyperthyroidism. In addition, the hypertension appears to be reversible following successful treatment of the hyperthyroid state.  相似文献   
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