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哺乳动物卵巢中的细胞凋亡及其调节 总被引:3,自引:0,他引:3
细胞凋亡是近几年细胞生物学研究的热点。卵巢中发生的生殖细胞减少、卵泡闭琐和黄体退化都与细胞凋亡密切相关。就上述三个过程中的细胞凋亡进行了概述 ,并简要介绍了新近发现的几种因素对卵巢细胞凋亡的调节。 相似文献
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Sílvio Peixoto Greg Coman Stuart Arnold Peter Crocos & Nigel Preston 《Aquaculture Research》2005,36(7):666-673
Oocyte maturation and gonadosomatic index (GSI) of eyestalk ablated Penaeus monodon females collected from the wild and from two first‐generation domesticated lines were assessed. Frequency and diameter of the different oocytes, and the intensity of oocyte atresia, were compared among groups through histological assessments of the sections of the middle ovarian lobe. Digitized images from ovary sections were used to record the frequency and diameter of different oocyte types. Spawning performance of the three groups were expressed in terms of the percentage of females that spawned at least once (productive females), time from eyestalk ablation to first spawning (latency period) and the number of spawnings per female stocked. Final ovarian maturation was attained in all groups, as indicated by the presence of mature oocytes with cortical rods (cortical oocytes), dark‐green ovarian colour and high GSI values (5.83–6.86%). However, domesticated groups presented significant larger immature oocyte types (previtellogenic and yolky oocytes) and smaller cortical oocytes compared with wild females, indicating a reduced vitellogenic activity during final oocyte maturation. Additionally, the frequency of atresia was comparatively higher for both domesticated groups, which could be related to their inferior spawning performance. The implications of these results on the reproductive potential and development of domesticated P. monodon are discussed. 相似文献
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Robert N. White BSc BVetMed Nicholas J. Macdonald BVetMed Carolyn A. Burton BVetMed PHD 《Veterinary radiology & ultrasound》2003,44(5):514-521
A retrospective study of the use of intraoperative mesenteric portovenography (IOMP) in the surgical management of congenital portosystemic shunts in 100 dogs and cats was performed. Each portovenogram was scored using a subjective visual analogue scale (VAS) and was assessed for the presence of portal atresia or hypoplasia. VAS scores and portal hypoplasia assessments were obtained for portovenogram images obtained for each animal both before shunt manipulation (preligation) and following the temporary, complete ligation of the vessel (postligation). In each patient, surgical records were reviewed to ascertain the degree of shunt attenuation that was achieved at surgery. Hepatic portal vasculature was significantly different on postligation compared with preligation IOMP. Sixty-two percent of animals had apparent portal hypoplasia or atresia on their preligation IOMP. The majority of these (81%) had an improvement in portal vasculature on postligation IOMP. It was concluded that both preligation and postligation IOMP provided valuable information regarding the morphology of congenital portosystemic shunts. An accurate assessment of an animal's portal vasculature could only be made following the interpretation of a postligation portovenogram, and these findings significantly influenced the surgical management of the patient. Although individuals with high postligation VAS scores were more likely to achieve full shunt attenuation at surgery, there was no quantifiable relationship between IOMP findings and the degree of shunt attenuation achieved. 相似文献
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S. Skov Hansen C. Mattei H. Treffenberg Pettersson M. Grabski 《Equine Veterinary Education》2021,33(11):e433-e437
This report describes successful surgical correction and long-term survival of a case of large colon atresia in a 24-h-old Warmblood colt, referred with signs of unrelenting abdominal pain and a suspicion of meconium impaction. Radiographic and ultrasonographic examination was indicative of large colon meconium impaction with secondary ileus. Due to deterioration of the foal, surgery was recommended. An atretic segment was found between the left ventral and dorsal large (ascending) colon. A band of fibrous tissue with no identifiable lumen connected the segments. Surgical correction was done by performing a stapled side-to-side anastomosis. Twelve days after surgery, the foal was discharged. Twenty-two months after discharge, the owner reported the foal developing as expected compared with its peers, but had a mild, self-limiting episode of colic at 20 months of age. 相似文献
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A 2-month-old, male alpaca had a 1-month history of mucoid ocular discharge from the left eye. Signalment, history and clinical findings were suggestive of a congenital nasolacrimal outflow obstruction. A dacryocystorhinogram confirmed bilateral nasolacrimal duct atresia, which involved the distal half of both nasolacrimal ducts. In order to establish alternative outflow, a conjunctivomaxillosinusotomy and conjunctivorhinostomy were performed on the right and left eye, respectively. The surgical openings remain patent after 11 months, and there have been no clinical signs of nasolacrimal disease. 相似文献