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51.
A 13-year-old mare presented for evaluation of recurrent colic episodes. The horse was diagnosed with a mass within the spleen at the ultrasound examination of the abdomen; the levels of Serum Amyloid A and the fibrinogen were high and so a presumptive diagnosis of an abscess involving the spleen was made base on clinical, ultrasonographic and laboratory findings and it was decided to perform n exploratory laparotomy for a definitive diagnosis and possible treatment. Upon abdominal exploration a mass involving the spleen, the lateral wall of the ventral colon adherent to the left abdominal wall was diagnosed and with an intraoperative ultrasound examination a linear hyperechoic foreign body was diagnosed within the mass. It was removed through an enterotomy of the left ventral colon that allowed the digital exploration of the mass without spilling of pus within the peritoneal cavity. The horse was discharged and the long term follow-up revealed no complications and no more signs of abdominal pain.  相似文献   
52.
OBJECTIVE: To describe surgical technique and outcome after laparoscopic closure of the nephrosplenic space for treatment of recurrent left dorsal displacement of the left colon (LDDLC) in standing horses. STUDY DESIGN: Retrospective study. ANIMALS: Forty-four horses with LDDLC. METHODS: Laparoscopic portals were located in the left flank region. After administration of etilefrin intravenously to contract the spleen, the dorsal splenic margin was sutured to the nephrosplenic ligament to obliterate the nephrosplenic space. Horses were re-examined (< or = 3 years) for history of recurrence. In addition, medical records of 4,852 horses treated for colic over 16 years were evaluated to establish incidence of LDDLC and recurrence after treatment. RESULTS: Splenic contraction facilitated suture placement and closure of the nephrosplenic space was achieved without complications. LDDLC recurrence did not occur although 5 horses had subsequent episodes of colic; 4 horses had displacement of the ascending colon between the spleen and body wall. Review of medical records revealed an incidence of LDDLC of 6% and recurrence of 21% in a population of horses with signs of colic. CONCLUSION: Laparoscopic closure of the nephrosplenic space, facilitated by etilefrin-induced splenic contraction can be efficiently performed in standing horses. CLINICAL RELEVANCE: Laparoscopic ablation of the nephrosplenic space should be considered in horses that are predisposed to recurrent LDDLC.  相似文献   
53.
OBJECTIVE: To evaluate outcome after laparoscopic closure of the nephrosplenic space in horses that had previous nephrosplenic entrapment of ascending colon (left dorsal displacement of the left colon; LDDLC). STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Horses that had previous LDDLC. METHODS: Medical records of horses that had LDDLC and subsequent laparoscopic nephrosplenic space closure between 2002 and 2004 were retrieved. Follow-up information was obtained by telephone interview of owners. Preoperative versus postoperative comparisons were: incidence of LDDLC, incidence of colic signs, and incidence of ventral celiotomy. Data were analyzed using a chi2-square test with significance set at P<.05. RESULTS: Ten horses met the inclusion criteria. Mean follow-up was 22 months. No horses had recurrence of LDDLC; however, 3 horses had colic signs subsequently that required surgical intervention. Over the follow-up period there was a significant decrease in the total incidence of colic and ventral celiotomy. Technique modifications included use of different cannula site locations, use of polyglyconate suture material for nephrosplenic space closure, and development of a custom cannula. CONCLUSIONS: Laparoscopic nephrosplenic space closure prevented recurrence of LDDLC, and significantly lowered the overall incidence of colic and ventral celiotomy. The custom-designed cannula provided good access to the operative site and no complications were encountered with use of polyglyconate suture material for nephrosplenic space closure. CLINICAL RELEVANCE: Closure of the nephrosplenic space will prevent LDDLC; however, other surgical lesions can occur.  相似文献   
54.
The peripheral washout sign was first described in delayed dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) using a small molecular contrast medium in solid lesions of the human breast and liver. It was found to be 100% specific for malignant lesions and could therefore potentially be used as an additional noninvasive diagnostic tool differentiating malignant from benign lesions. The origin of this phenomenon has not yet been explained. The objective of this study was to translate the peripheral washout sign as seen in solid tumours in delayed DCE‐MRI in human onto an animal model for further assessment of DCE‐MRI characteristics and histological analysis. Small molecular contrast medium DCE‐MRI was performed over 42 min in experimental colon carcinoma grown subcutaneously in rats. Qualitative and quantitative analyses for evaluation of presence and characteristics of the peripheral washout sign were accomplished, defining four centripetally distributed tumour zones (central, intermediate, peripheral and marginal). One hundred per cent of the carcinomas demonstrated a peripheral washout sign in DCE‐MRI starting at 20 min after bolus injection. Histomorphological analysis was performed for tissue classification and evaluation of microvasculature. Quantitative analysis revealed different enhancement profiles of the four tumour zones. Histology indicated centripetally asymmetric vascularization and vascular endothelial growth factor VEGF/VEGF receptor 2 expression within the tumour tissue. Thus, peripheral washout sign can be translated to an animal model. However, comparison of small molecular contrast medium DCE‐MRI with histology revealed that histology alone does not explain the occurrence of the peripheral washout.  相似文献   
55.
In an 18-year-old Paso Fino mare presented with mild colic of 36 h duration, a luminal obstruction was found on rectal palpation in the most oral part of the rectum, and this appeared to be caused by a tight band on the left side. A standing procedure was used that involved pararectal dissection with long-handled instruments to the level of the constricting band, guided by a hand in the rectum. A hooked bistoury designed for treating entrapped epiglottis was used to transect the band, which immediately released the obstruction and allowed manual evacuation of the aboral end of the small colon. The band was most likely the pedicle of a pedunculated lipoma that had encircled the oral end of the rectum. The mare made a complete recovery.  相似文献   
56.
57.
There is a discrepancy in the literature on potential digesta separation mechanisms in horses, with both a selective retention of fine and of large particles postulated in different publications. To assess the net effect of such mechanisms, we fed ponies on a hay‐only diet a pulse dose of whole (unchopped) marked hay together with a solute marker, collected faeces on a regular basis, measured marker concentrations in whole faeces and in their large (2.0–16 mm), medium (0.5–1.0 mm) and small (0.063–0.25 mm) particle fraction, and calculated the corresponding mean retention times (MRTs). For comparison, the same experiment was performed in goats. In goats, as expected, MRTsolute (35 hr) was significantly shorter than MRTparticle (51 hr); only a very small fraction of particle marker was excreted as large particles (2%); and the MRT of these large particles was significantly shorter than that of small particles (with a relevant difference of 8.6 hr), indicating that those few large particles that escape the rumen do so mostly soon after ingestion. In ponies, MRTsolute (24 hr) did not differ from MRTparticle (24 hr); a higher fraction of particle marker was excreted as large particles (5%); and the MRT of these large particles was longer than that of small particles (but with a non‐relevant difference of less than 1 hr). These results indicate that no relevant net separation of digesta phases occurs in horses and that selective particle retention mechanisms in the large intestine are unlikely to represent important characteristics of the horse's digestive physiology.  相似文献   
58.
目的了解结肠癌组织中中期因子(MK)、尿激酶型纤溶酶原激活物(uPA)表达及其与结肠癌临床病理特征的关系。方法收集55例病理学确证的结肠癌组织标本(病例组)和30例结肠癌癌旁的正常组织标本(对照组),采用免疫组织化学方法(SP法)检测其MK、uPA的表达。结果病例组中MK、uPA表达率分别为56.36%、61.82%,对照组分别为13.33%、16.67%,两组的差异均有统计学意义(P〈0.01)。结肠癌组织中MK、uPA表达与癌组织的分化程度、浸润深度、淋巴结转移有相关性,而与性别和年龄无相关性。MK与uPA表达呈正相关(r=0.44,P〈0.05)。结论 MK、uPA表达与结肠癌侵袭、转移密切相关,二者联合检测可作为判断结肠癌发展及预后的指标。  相似文献   
59.
【研究目的】抗生素是某些微生物在生长代谢过程中产生的次级代谢产物,具有抑制或杀死微生物的能力。根据抑菌带的长短,即可判断氨苄西林对不同细菌的影响以及不同浓度氨苄西林对同一种菌的影响,初步判断其抗菌谱。【方法】采用滤纸条法测定氨苄西林的抗菌谱,选用的菌种为金黄色葡萄球菌,大肠杆菌,枯草芽孢杆菌。【结果】随着氨苄西林浓度的增加,抑菌带的长度逐渐增长,抑菌效果越来越强,但同一浓度的氨苄西林对金黄色葡萄球菌,大肠杆菌,枯草芽孢杆菌的抑制效果差别不是很明显。【结论】氨苄西林通过抑制转肽作用使细菌的细胞壁解体而死亡。  相似文献   
60.
Morphofunctional characteristics of the large intestine are rarely explored to understand the physiology, behavior and ecology of neotropical primates. In this study, we analyzed the histometric parameters of the large intestine of hybrid marmosets (Callithrix sp.) captured in forest fragments of Viçosa-Brazil, under seasonal interference. These animals were predominantly insectivorous in the rainy season and gummivores in the dry season. Large intestine fragments were collected and processed according to histological methods and stained with toluidine blue for general analysis, periodic acid of Schiff (PAS) and Alcian blue (AB) for goblet cells, Grimelius and Masson Fontana for argyrophil and argentaffin endocrine cells. Several histometric parameters were more expressive in the large intestine of the rainy season marmosets: greater thickness of the parietal layers, greater number of argyrophil and argentaffin endocrine cells, and AB-positive goblet cells, characteristics favor secretomotor functions and reduce the passage time of the fecal bolus, which is consistent with an insectivorous diet. In contrast, parameters such as crypt width, height of the absorptive cells and striated border, and the number of PAS-positive cells were more expressive in the dry season marmosets, reflecting the need for longer passage time for digestion and absorption of food items from tree gum, which are more complex and demand the action of microorganisms present in the large intestine, as well as greater protection against the abrasive action of dietary fibers and against microorganisms. Thus, it can be said that the marmoset's large intestine has morphological adaptations to maximize energy intake from the diet, which alternates under the influence of seasonality.  相似文献   
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