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排序方式: 共有417条查询结果,搜索用时 20 毫秒
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3种甘蓝型油菜雄性不育系花药发育的细胞学研究 总被引:15,自引:0,他引:15
采用石蜡制片方法,对3种甘蓝型油菜雄性不育系及其恢复系的小孢子发生和花粉发育过程进行比较解剖学观察,以确定其花粉败育的时期和细胞学特点。研究结果表明:波里马雄性不育系花药发育受阻于孢原细胞分化期,雄蕊不能分化形成花粉囊。S43A雄性不育系花粉败育的时期发生在小孢子四分体至单核花粉期,败育的特点为小孢子细胞质液泡化,逐渐变形解体,不能进行有丝分裂形成二胞花粉,同时绒毡层细胞过度液泡化,并提早解体死亡。G022A不育系的花药在小孢子发生的不同阶段均出现败育现象,最早的败育表现为花粉母细胞的退化解体;有些因花粉母细胞减数分裂异常不能形成小孢子四分体;还有的因小孢子在四分体中不能正常释放而败育,并伴随着绒毡层细胞的畸形化、异常生长等现象。 相似文献
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Petterino C Guazzi P Ferro S Castagnaro M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):401-404
A 6-year-old, spayed, female, domestic shorthair cat was presented for decreased activity. A nodular lesion was found in the skin extending into the subcutaneous tissue of the right abdominal flank. On lateral and ventrodorsal radiographs of the thorax, an opacity involving the entire right caudal lung lobe and pleural effusion were noted. Cytologic evaluation of cells in the thoracic fluid and in the mass revealed a population of atypical epipthelial cells with marked anisocytosis and high N:C ratios, organized in acinar-like clusters. Multinucleated cells and several mitotic figures were found. The cytologic interpretation was carcinoma. Because of the progressive severity of clinical signs, the cat was euthanized. Histologic evaluation of tissues obtained at necropsy indicated a bronchogenic adenocarcinoma in the lung, with metastasis to the skin of the right flank, but no involvement of the digits. Based on immunohistochemical stains, the neoplastic cells strongly co-expressed cytokeratin and vimentin, and were negative for S-100 and actin-specific antigen. Bronchogenic adenocarcinoma is an uncommon neoplasm in cats, and the digits are the most common sites of metastasis. This case was unusual in that the skin of the abdominal wall was the primary site of metastasis, with no involvement of the digits. 相似文献
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Graves TK Barger AM Adams B Krockenberger MB 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):409-412
A 3-year-old Boxer was presented with progressive diarrhea, vomiting, and lethargy of 5-months duration. The dog had watery black feces, a mature neutrophilia, and microcytic anemia. Cytologic evaluation of a direct fecal smear stained with Wright's-Giemsa revealed numerous encapsulated, narrow-based, budding organisms consistent with Cryptococcus sp. Pyogranulomatous inflammation and Cryptococcus organisms also were observed in ultrasound-guided fine-needle aspirates of the small intestine and mesenteric lymph nodes, and in histologic sections of colonic biopsies obtained by endoscopy. Multifocal chorioretinitis by fundic examination was consistent with systemic mycosis, and the reciprocal antigen titer (1600) on a cryptococcal antigen latex agglutination test for Cryptococcus neoformans was markedly increased. Using immunohistochemistry, the organism was identified further as C neoformans var. grubii (C neoformans var. neoformans serotype A). After 3 weeks of antifungal treatment, ultrasound examination revealed urinary bladder wall thickening, and Cryptococcus organisms were found in a urine sediment preparation. After 4 months of treatment, the dog was clinically normal and had no abnormal findings on CBC, serum biochemistry, urinalysis, or fecal cytology; however, the antigen titer remained unchanged, mesenteric lymphadenomegaly and jejunal wall thickening were still evident, and cytologic evaluation of fine-needles aspirates of the jejunal wall revealed budding Cryptococcus organisms. Intestinal involvement in dogs with cryptococcosis is rare, and diagnosis by fecal cytology has not been documented previously. 相似文献
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Casimire-Etzioni AL Wellehan JF Embury JE Terrell SP Raskin RE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(1):43-46
A 4.5-year old, male African spur-thighed tortoise (Geochelone sulcata) was presented to the University of Florida Veterinary Teaching Hospital with a 2-week history of lethargy, anorexia, constipation, dyspnea, and coughing up fluid or vomiting. Laboratory results included an inflammatory leukogram and a marked increase in plasma uric acid concentration. Synovial fluid from multiple joints was thick, chalky white, and opaque, with a grainy consistency. Microscopically, the fluid contained numerous brown, needle-like crystals consistent with urates (gout). Gross necropsy findings and histopathology confirmed a diagnosis of systemic gout, with urate deposition, gout tophi, and underlying necrosis in multiple organs, including kidneys, lung, and liver. Dehydration with concurrent renal insufficiency may have impaired urate excretion and led to a build-up of urates in the blood and tissues of this tortoise. A high protein diet also may have contributed to the development of gout. Cytologic evaluation of synovial fluid can be used as a quick and definitive tool to diagnose gout in tortoises. 相似文献
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Bauer NB O'Neill E Sheahan BJ Cassidy J McAllister H 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(3):168-172
A 3-year-old Wirehaired Fox Terrier was presented to the University Veterinary Hospital, University College Dublin, for evaluation of chronic cough of 8-months duration. Bronchoscopy showed a severely dilated collapsed left principal bronchus filled with highly viscous white mucus. Cytologically, globular lipid-like material and round concentrically laminated crystalline structures were evident within the proteinaceous mucus. These findings resembled the calcospherites and granular caseous debris often observed in human tuberculous patients. A Ziehl-Neelsen-stained cytocentrifuged preparation of material obtained by bronchoalveolar lavage revealed a few acid-fast rods within macrophages, suggestive of tuberculosis. At necropsy, granulomas with caseous necrosis were present in the lung parenchyma, bronchial and mediastinal lymph nodes, liver, pancreas, and mesentery. Granulomas were adherent to both kidney capsules and to the diaphragm. Histologically, there was evidence of mild calcification within caseous granulomas, which was confirmed by von Kossa's stain. Using Ziehl-Neelsen stain, acid-fast rods were identified within granulomas; bacterial culture was positive for Mycobacterium bovis. The cytologic findings in this case have not been reported previously in dogs and demonstrate a possible correlation between tuberculosis and calcospherite-like bodies with caseous, globular material in bronchial mucus, similar to that described in human patients. 相似文献
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Megan N. Caudill Justin M. Stilwell Elizabeth W. Howerth Bridget Garner 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2019,48(1):67-70
A 4‐year‐old, spayed female French Bulldog was presented for respiratory distress and suspected aspiration pneumonia after oral administration of activated charcoal for possible ingestion of a suspected toxic dose of trazodone. The patient had a moderate volume of pleural effusion, which contained free and intracellular black particulate matter consistent with charcoal. Due to presumed charcoal aspiration with subsequent lung rupture, the right middle and right caudal lung lobes were surgically removed. Histology revealed abundant black debris consistent with charcoal and severe granulomatous inflammation. Based on the clinical, gross, and histologic findings, a diagnosis of severe, chronic, locally extensive, aspiration pneumonia and lung rupture with secondary pleuritis and mediastinitis due to charcoal aspiration was made. Aspiration pneumonia is the main complication of activated charcoal administration, which can incite extensive, granulomatous inflammation in the respiratory tract. To the authors’ knowledge, this is the first report describing the cytologic and histologic findings associated with inadvertent charcoal aspiration in a veterinary species. 相似文献