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61.
The medical records of 171 dogs with traumatic hip luxations were examined. German shepherds, mixed breeds, and poodles were significantly overrepresented. The mean age of the patients at the time of diagnosis was 4.4 years (range 5 months to 14 years). Vehicular trauma caused 83% of the 133 luxations where the etiology was known; 53% had at least one other diagnosed traumatic injury. Long-term results were obtained from owner questionnaires (25 dogs) or clinical and radiographic examinations (11 hip joints). The short-term recurrence rate after closed reduction (47.3%) was higher than that after surgical reduction using any of the three surgical techniques most frequently used here (9.5, 12.5, and 14.3%), even when the operation was performed after failure of a closed reduction (11.8%). Excluding dogs that had a femoral head ostectomy, 68% (17 of 25) of the dogs had a normal gait, 16% had only a mild lameness, and 16% had more severe lameness when evaluated on an average of 31 months after repair. Of 11 hip joints radiographed on an average of 25 months following repair, five had no radio-graphic abnormalities related to the luxation and six showed one or more of the following: periosteal new bone formation, femoral head subluxation, partial resorption of the femoral head, periarticular osteophytes, and subchondral bone erosion. Closed reduction should be the initial treatment of choice in uncomplicated luxations even though the rate of reluxation is high, because it avoids the need for surgery in approximately one half of affected dogs and does not increase the recurrence rate following subsequent surgical reduction.  相似文献   
62.
In an attempt to standardize methods of assessment of Eurygaster spp. and Aelia spp., some methods published in USSR, Romania and Turkey are reviewed and details given. These are: 1) counting overwintering adults in quadrats or along a line; 2) counting old adults in quadrats or by sweep net after migration; 3) counting nymphs in quadrats. Methods of assessing crop loss caused are: 1) counting attacked stems of young wheat; 2) counting attacked ears; 3) identification and counting of attacked grain at harvest; 4) caging different numbers of nymphs and adults, and taking yields, grain weight, germination etc.; 5) assessing the effect on baking quality of flour etc. The effects of different numbers of insects per m2 on yield are given. It is suggested that standardization of such methods would lead to improved cooperative studies between different countries.  相似文献   
63.
SUMMARY: Although cryptococcosis is a well-characterised disease of cats, the factors predisposing individuals to infection are unknown. As an indication of the immune status of an individual, lymphocyte subsets can be analysed. Reference ranges for feline lymphocyte subsets (Pan T+, CD4+, CDS+ and B cells) were established using a rapid whole blood technique and flow cytometry. There were no effects of age or sex on lymphocyte subset values. The numbers of circulating leucocytes and lymphocyte subsets were determined in FIV-positive and FIV-negative cats with cryptococcosis and compared with a group of healthy control cats.
There were only minor differences in the numbers of lymphocyte subsets among the subgroups of cats examined in the study and the predisposition to cryptococcosis in cats could not be explained by deficiencies in lymphocyte subsets. There was a tendency for FIV-negative cats with cryptococcosis to have reduced numbers of circulating CD4+ cells and lower CD4:CD8 ratios compared with normal cats, although the interpretation of this finding was complicated by the wide reference range for normal cats. The extent to which this is the cause of the fungal infection was not determined.
The only difference in leucocyte or lymphocytes subset values between FIV-negative cats with cryptococcosis and FIV-positive cats with cryptococcosis was that the CD4+ percentage was lower in the FIV-positive cats. The absolute CD4+ count was similar however, in FIV-positive and FIV-negative cryptococcosis cases. On the basis of this and other available information, the categorisation of cryptococcosis as a disease defining the AIDS phase of FIV infection may be incorrect.  相似文献   
64.
The skin of 100 dogs undergoing clean or clean-contaminated surgical procedures was prepared with povidone-iodine (PI) or 4% chlorhexidine gluconate (CG) with saline or 70% isopropyl alcohol rinse. Skin bacteria at the incision site were quantified with Replication Organism Detection and Counting (RODAC) plates immediately before and after skin preparation in the preparation room, in the operating room, and postoperatively. The percentage of bacterial reduction, negative cultures, cultures with more than five colony-forming units, and skin reactions for each technique were calculated for each sample period and analyzed with the analysis of variance and Fischer tests. The percentage of bacterial reduction for all techniques was significant and comparable with results of a previous experimental study. There were no significant differences in percentages of bacterial reduction between PI and the CG techniques for surgical times up to 8 hours. There were fewer negative cultures and more cultures with high bacterial counts with PI than with CG and saline after the cleansing scrub. There were fewer negative cultures after surgery with CG and alcohol than with the other two techniques. Duration of the surgical procedure did not significantly affect the culture results. Significantly more skin reactions occurred with PI. The authors conclude that PI and 4% CG with a saline rinse are equally effective in antimicrobial efficacy under clinical conditions. However, 4% CG with a 70% isopropyl alcohol rinse may be inferior in residual antimicrobial activity.  相似文献   
65.
66.
A neurological disorder in Merino sheep, characterised clinically by progressive posterior ataxia and microscopically by Wallerian degeneration in thoracic segments of the spinal cord, is described. Animals of both sexes were affected, with the earliest onset of disease being at 5 months of age. Most affected animals died before 2 years of age. The clinical, pathological and epidemiological features suggest that this degenerative thoracic myelopathy is a previously unrecognised entity differing from other reported causes of ataxia in sheep in Australia.  相似文献   
67.
68.
INTRAOPERATIVE RADIOTHERAPY OF CANINE BLADDER CANCER   总被引:2,自引:0,他引:2  
Thirteen dogs had partial surgical extirpation followed by whole bladder intraoperative radiotherapy for urinary bladder cancer. Eleven of the neoplasms were transitional cell carcinomas (five Stage T1, six stage T2); one was rhabdomyosarcoma (Stage T2), and one was leiomyosarcoma (Stage T2). Histopathologic evaluation showed that neoplasia extended to the margins of the excised tissue in at least 11 of the 13 dogs. Radiotherapy from a 137Cs teletherapy machine was applied to the surgically exteriorized bladder, with doses at the 90% isodose level varying from 2188 to 2888 cGy (10 of 13 dogs receiving 2670–2700 cGy). Sixty-one percent of the dogs were alive at 1 year, 30% at 18 months, and 15% at 2 years. From the time of initial clinical signs of bladder neoplasia, 69% of the irradiated dogs were alive at 1 year, 46% at 18 months, and 23% at 2 years (one dog is still living, at 70 months). Of the owner-reported or clinically determined posttherapy complications, there was increased frequency of urination in 46% of the dogs, urinary incontinence in 46%, cystitis in 38%, and stranguria in 15%. Either persistence or recurrence of neoplasia was found in six (46%) of the dogs and metastasis in four (30%), with two of these having both recurrence and metastasis. Qualitative assessment of the complications was not done, but owner-perceived severity of the complications, metastasis, or diagnosed persistence or recurrence of the neoplasm were the major reasons for ultimately killing most of the dogs.  相似文献   
69.
1. When laying hens are stressed some retain their eggs in the shell gland beyond the normal time of laying and this can result in the deposition of extra-cuticular calcium which makes brown eggs appear paler. 2. Three different types of enriched modified cage were compared: the location where eggs were laid was recorded and shell colour was measured using a reflectometer. 3. In 2 types of cage with enclosed nest boxes more eggs (80%) were laid in the nests than in a design with nest hollows in the open part of the cage (41%). 4. The eggs from the cages with enclosed nests were darker (had less extraneous calcium) than those with open nest hollows. This implies that in the designs with nest boxes fewer eggs had been retained and the hens may have been less stressed. 5. The results support previous evidence that to reduce stress and improve welfare it is desirable to provide enclosed nest sites for caged laying hens.  相似文献   
70.
A reassessment of podzol formation processes   总被引:2,自引:0,他引:2  
Translocated (oxalate-soluble) Al and Fe are present predominantly in inorganic forms in the B2 horizons of the five pcdzol profiles examined: A1 as imogolite and proto-imogolite allophanes, and Fe as a separate oxide phase. Below the top few cm of the B2 horizon, over 75 per cent of the extractable (acid-plus alkali-soluble) organic matter is present as Al-fulvates, largely sorbed on allophanic material. The Bh horizons of the Iron Humus Podzol and Iron Podzol intergrades are distinguished by very high levels of organically bound Fe (soluble in EDTA solution), five to ten times more than in immediately adjacent A2 or B2 horizons, and also by larger humic acid contents than in comparable B2, levels in typical Iron Podzols. Inorganic forms of translocated Al and Fe are probably absent from two of the three Bh horizons examined, and also from the Bhg horizon overlying the thin iron pan in the Peaty Podzol. The organic matter in this Bhg horizon is saturated with Al rather than Fe. Chemical and physical processes which could lead to evolution of a profile along the genetic sequence, Iron Podzol, Iron Humus Podzol, Peaty Podzol, are postulated. During the formation of an Iron Podzol, positively charged inorganic sols carry aluminium, silicon and iron from the A2 and deposit them in the B2 horizon; subsequently, with the development of an H layer, colloidal humus migrates through the A2 and precipitates on the positive colloids at the top of the B2 horizon to form a Bh horizon, in which remobilized ferric species are trapped by the organic matter. In higher rainfall areas, occasional waterlogging above the oxide-impregnated B2 leads to a thin iron pan, separating permanently oxidizing conditions below from seasonally waterlogged and reducing conditions above.  相似文献   
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