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341.
TheApplicationofGIsinSmallWatershedClassificationinLoessPlateauZhuJinzhao,WuBin,BiHuaxing,ZhouChangqingCollegeofSoilandWaterC...  相似文献   
342.
Seven cases of cutaneous hemangioma and nine of cutaneous hemangiosarcoma were diagnosed from biopsy specimens of 15 Domestic Shorthairs of 5,091 cats that were examined by necropsy or biopsy during the 5-year period from 1 January 1986 through 31 December 1990. All but three cats were male. Tumor cells of both hemangiomas and hemangiosarcomas were immunoreactive for factor VIII-related antigen and for vimentin by the avidin biotin peroxidase complex method. In cats with a median age of 10 years, hemangiomas occurred in skin with pigmented hair in six of seven cases without apparent site predilection. These solitary tumors did not recur after excision although one cat (No. 3) subsequently developed cutaneous hemangiosarcoma at another site. Seven of nine hemangiosarcomas occurred in dermis and subcutis of the head, usually on the pinna. All five hemangiosarcomas of the head, for which cutaneous pigmentation could be determined, occurred in unpigmented skin. Cats with hemangiosarcoma had a median age of 12.5 years at the time of diagnosis. Metastasis has not been documented, but hemangiosarcoma has recurred, from 1 month to 2 years after excision, in 6/7 cats that were studied.  相似文献   
343.
Disappearance of acetic acid was quantified to determine whether removal of this acid from the reticulorumen is altered when ruminal acetic acid concentrations are elevated. Ruminally fistulated beef steers (n = 3 per experiment; BW = 320 +/- 9 kg) were fed eight times daily a 46% corn-based concentrate:54% mixed hay diet to meet maintenance energy requirements (3.5 kg of DM/d). In situ production of acetic acid, determined by pulsed-continuous infusion of [1-14C]acetic acid, was 530 mmol/h (CV = 12%). Disappearance from the reticulorumen (i.e., presumed absorption) was 460 mmol/h (CV = 2%) or 87% (CV = 2%) of ruminal production. Variation is described within an operational steady state. Acetic acid concentrations were increased by continuous infusion of unlabeled acetic acid into the reticulorumen. Ruminal disappearance (mmol/h) increased when this simulated production was elevated up to and exceeding in situ rates reported previously (530 to 2,700 mmol/h). These data suggest that two-thirds to three-fourths of ruminal acetate production disappeared across the reticuloruminal wall when concentration was elevated; the complement exited from the rumen with the liquid phase. The reticulorumen has an additional capacity to remove acetic acid; however, it does so with an apparent reduced efficiency at higher production rates. Liquid out-flow may affect the efficiency of reticuloruminal disappearance. Sites distal to the rumen become quantitatively important when ruminal acetic acid concentrations are increased.  相似文献   
344.
Eighteen dogs with malignant melanoma of the oral cavity were treated with high-dose per fraction (0–7–21) radiation therapy. Eight hundred cGy was administered on days 0, 7, and 21 for a total dose of 2,400 cGy in 3 weeks. Of 17 dogs evaluated, 9 (53%) had a complete remission and 5 (30%) achieved a partial remission with an overall response rate of 83%. Local failure occurred in 2 of the 9 dogs where a complete response was initially observed. One dog died of intercurrent disease, and one died of metastatic disease without evidence of local recurrence. Five dogs are alive and free of disease 9 to nineteen months from the initiation of therapy. The 0–7–21 protocol was well-tolerated, and acute radiation reactions were low-grade and limited to the skin. The results of this study demonstrate that oral melanomas in dogs are responsive to radiation. 0–7–21 radiation therapy offers a viable alternative to radical excision, especially when tumor volume or location would require cosmetically or functionally debilitating surgery.  相似文献   
345.
本文应用酶免疫试验(ELISA)、反向间接血凝试验(RIHA)和中和试验(NT)三种方法对6份疑似HBV感染的待测血清进行测定,借此探讨ELISA检测中出现假阴性现象,认为假阴性是由检测前滞现象引起。  相似文献   
346.
The dependency of the secretory function of the feline major vestibular gland (Bartholin's gland) on the ovarian steroid hormones was studied histochemically. After estrogen (estradiol-17 beta or diethylstilbestrol), progesterone or a combination of these was administered to cats which were previously ovariohysterectomized, the major vestibular glands were removed, embedded in paraffin, sectioned, and stained by alcian blue, periodic acid-Schiff or peroxidase-labeled lectin (peanut agglutinin and wheat germ agglutinin). The vividly positive reactions to the stainings applied were observed in the secretory epithelial cells of the major vestibular glands in the estrogen treated animals. The dependency of the secretory function of the major vestibular glands on the estrogen was demonstrated in this study.  相似文献   
347.
348.
A field study utilizing 145 mares of various age and breeding status was conducted to determine reproductive performance under native range conditions with only limited supplemental feeding. All mares had an average initial body condition score of 4.5 and a final score of 5.1 by the time breeding was completed and mares returned to pasture. Average foaling rate was 80%, and mares that had not conceived during the previous breeding season had a foaling rate of 94%, which was higher (P<.05) than 74% for lactating mares. Mares 16 years and older had a significantly lower foaling rate (P<.05) than younger mares. Old mares that were lactating at time of breeding had only a 37% foaling rate, which was less (P<.05) than for young lactating mares. The 94 mares bred by natural cover or artificial insemination that actually foaled required 1.43 cycles per conception. Lactating mares in the oldest age group required more cycles per conception (P<.05) than open mares, and these older, lactating mares also required more cycles per conception than younger mares with foals at side. Those mares diagnosed as pregnant or open at 45 days post breeding had a pregnancy rate of 97%. Average pregnancy loss for all mares was 7.7%. These data indicate that lactating mares in moderate body condition tended to skip a breeding season and that a body condition score of 5 was only marginally acceptable, especially in the case of lactating mares. Authors' address: Equine Science Program, Department of Animal Science, Texas Agricultural Extension Service, Texas A&M University, College Station, TX 77843. Technical Article Number 30023, Texas Agr. Exp. Sta.  相似文献   
349.
Recent advances in uroendoscopy have allowed diagnostic evaluation of the lower urinary tract in most of our canine and feline patients. By providing a magnified view of the luminal surfaces of the lower urinary tract, uroendoscopy provides useful diagnostic information that is not readily available even by more invasive techniques.  相似文献   
350.
Objective: To establish baseline values for descending thoracic aortic blood flow parameters as determined with a transesophageal combined M‐mode and pulsed Doppler ultrasound‐based monitoring method. Design: Preliminary observational study. Setting: University small animal teaching hospital. Animals: The study population consisted of anesthetized canine patients undergoing nonemergent surgeries. Prospectively set criteria for inclusion were adequate body size for placement of the esophageal probe and a nonemergent reason for surgery. The criterion for exclusion was recent trauma. Interventions: Placement of the transesophageal probe. Measurements and main results: Data was collected during 15 surgeries. Data from three dogs was excluded from data analysis (two recently hit by motor vehicles, one recently having undergone a total hip replacement). Each parameter was stable across time within each individual dog. The ranges of the descending thoracic aortic parameters across the 12 nonemergent cases were as follows: blood flow, 0.038–0.085 L min?1 kg?1; blood flow per beat, 0.31–0.84 mL kg?1; blood acceleration, 6–29 m s2?1; blood peak velocity, 38–105 m s?1; left ventricular ejection time interval 331–492 ms; and diameter, 0.30–0.93 mm kg?1. Conclusions: The range of descending thoracic aortic blood flow parameters encountered in this small group of dogs during nonemergent surgeries was broad; however, each parameter was quite stable across time with little change occurring in any dog during monitoring.  相似文献   
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