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661.
Light-based technologies are applied in various fields of medicine: for example optical diagnostics, light-activated therapy and surgery. Although light-based surgical procedures had hardly been a novelty, the revolutionizing moment for surgery came with the first use of light to cut tissue. Nowadays, surgical lasers are routinely used across numerous medical specialties, including gynaecology and urology. They are a part of the surgical treatment of benign prostatic hyperplasia, prostate carcinoma, penis carcinoma, genital skin lesions and orchidectomy. While in human urology lasers continue to establish their position as one of the standard surgical tools, veterinary patients are rarely treated with what here is still considered a technical innovation. However, through research on laser treatment of the prostate hyperplasia conducted on a canine model, veterinary medicine has gained a massive portion of data. It may prove beneficial for our clinical patients. In this review, we introduce the very principles of laser surgery as well as its current and future applications in oncologic surgery of the canine prostate gland and the male reproductive system.  相似文献   
662.
A 12-year-old Belgian draft horse presented for a right eye third eyelid mass and red-tinged ocular discharge of 3 months' duration. The third eyelid was excised and submitted for histopathology. On histopathologic examination, the mass was composed of both hemangiosarcoma and squamous cell carcinoma. The horse developed thickened eyelids and hemorrhagic ocular discharge from the right eye approximately 16 months following surgery, and was euthanized. Necropsy and histopathology confirmed local recurrence and regional metastasis of the hemangiosarcoma. This was an unusual case because there were two distinct neoplastic processes composing the same mass that could not be differentiated grossly.  相似文献   
663.
目的 探讨细胞角蛋白(CK)、核抗原(Ki67)、磷脂酰肌醇蛋白聚糖3(Gly-3)及抑癌基因P53在肝细胞癌(HCC)组织中的表达。方法 收集16例肝细胞肝癌患者癌组织及癌旁组织,采用免疫组化染色技术,分别检测CK、Ki67、Gly-3及P53,分析其表达情况。结果 免疫组化检测16例HCC癌组织中CK7、CK8/18、CK19的阳性率分别为50%(8/16)、93.8%(15/16)以及62.5%(10/16),Ki67的阳性率为75%(12/16),Gly-3阳性率为87.5%(14/16),P53的阳性率为50%(8/16)。结论 HCC患者癌组织中CK、Ki67、Gly-3及P53的表达有不同程度的上调,其中以CK8/18阳性率最高,Gly-3及Ki67次之,P53及CK7相对较低。  相似文献   
664.
Abstract: A 12‐year‐old, neutered male, mixed‐breed dog was presented to The Ohio State University Veterinary Teaching Hospital with a history of weight loss and weakness. Laboratory abnormalities reported by the referring veterinarian during the past year included increased alkaline phosphatase (ALP) activity, hyperalbuminemia, and nonregenerative anemia. On referral, the dog appeared hydrated and had moderate muscle wasting and hepatomegaly. A large lobular hepatic mass was observed ultrasonographically. Laboratory results included mild to moderate nonregenerative anemia, urine‐specific gravity of 1.035, 3+ proteinuria, increased serum activities of alanine aminotransferase (229 U/L, reference interval 10–55 U/L), ALP (813 U/L, reference interval 15–120 U/L), and the steroid‐induced isoform of ALP (676 U/L, reference interval 0–6 U/L), marked hyperalbuminemia (5.3 g/dL, reference interval 2.9–4.2 g/dL), and an increased A/G ratio (1.7). Hyperalbuminemia was confirmed by reanalysis on 2 different analyzers and by agarose gel electrophoresis, and colloid osmotic pressure (COP) was markedly increased (42.5 mmHg, reference interval 20–25 mmHg). Cytologic examination of a fine‐needle aspirate of the hepatic mass indicated hepatocellular proliferation; histologic examination of an excisional biopsy confirmed hepatocellular carcinoma. Three weeks after surgery, the albumin concentration, A/G ratio, COP, and ALT activity had normalized, but ALP activities remained high. We hypothesized that hyperalbuminemia developed secondary to hepatocellular carcinoma due to increased synthesis of albumin by malignant hepatocytes or due to decreased negative feedback from impaired hepatocellular osmoreceptivity. Hepatocellular carcinoma has been associated with paraneoplastic secretion of other proteins, but hyperalbuminemia has been reported only once in a human patient and has not previously in dogs.  相似文献   
665.
采用单管法一步完成端粒重复序列扩增法检测人肝癌细胞株,经不同浓度JA1及不同时间的作用前后端粒酶活性的变化,并采用流式细胞仪分析细胞周期的变化。结果显示,JA1可显著抑制人肝癌细胞端粒酶活性,而且这种抑制效果有剂量依赖性和时间依赖性。流式细胞仪分析细胞周期的变化表明,端粒酶活性被抑制后,肝癌细胞被阻滞在G2/M。同时,在检测标本中显示有明显的DNA低含量颗粒(“亚G1期”峰),表明肝癌细胞凋亡的存在。  相似文献   
666.
18F‐fluorodeoxyglucose positron emission tomography combined with computed tomography (18FDG‐PET/CT) has been shown to be effective for staging human oral squamous cell carcinoma (SCC) but its application for cats with oral SCC is unknown. Twelve cats with biopsy‐proven oral SCC were imaged with whole body 18FDG‐PET/CT to determine its value as a diagnostic imaging and staging tool and fine needle aspirates were obtained of accessible regional lymph nodes. All tumors were FDG avid and conspicuous on 18FDG‐PET/CT images, with an average of the maximum standardized uptake value 9.88 ± 5.33 SD (range 2.9–24.9). Soft tissue infiltrative tumors that were subtle and ill defined on CT were highly visible and more extensive on FDG‐PET/CT. Tumors invading the osseous structures were more similar in extent on 18FDG‐PET/CT and CT although they were more conspicuous on PET images. Three cytologically confirmed metastases were hypermetabolic on PET, while two of those metastases were equivocal on CT.  相似文献   
667.

Background

Survival times and tumor responses associated with malignant neoplasia of the lower urinary tract are poor despite the vast array of current treatments. Therefore, the evaluation of alternative treatments, such as intraarterial administration of chemotherapy (IAC) should be considered.

Objective

To describe a technique for superselective catheterization for IAC and to evaluate initial tumor response by ultrasonography after both IAC and intravenous administration of chemotherapy (IVC).

Animals

Client‐owned dogs with lower urinary tract neoplasia treated with either IVC (n = 15) or IAC (n = 11).

Methods

Retrospective study. An arterial approach via the carotid or femoral artery was utilized to obtain superselective access and administer chemotherapy in the IAC cases. Medical record review was performed, data were recorded, and recorded variables were evaluated statistically.

Results

Intraarterial chemotherapy was successfully administered in all cases. There was a significantly greater decrease in longest unidimensional measurement in the IAC group as compared to the IVC group (P = .013). The IAC group was also significantly more likely to have a tumor response as assessed by modified RECIST guidelines (P = .049). Dogs in the IAC group were significantly less likely to develop anemia (P = .001), lethargy (P = .010) and anorexia (P = .024).

Conclusion and Clinical Importance

This study demonstrated the feasibility and efficacy of performing IAC for lower urinary tract neoplasia. Further investigation is necessary as the follow‐up time was short and the impact on long‐term outcome and survival was not determined.  相似文献   
668.
Transitional cell carcinoma (TCC) is the most commonly diagnosed neoplasm in the urinary bladder. Distant metastases to the regional lymph nodes, lungs, abdominal organs or bones are noted in up to 50% of dogs at time of death. Surgical excision is often not practical as TCC typically involve the trigone of the bladder and/or occurs multifocally throughout the bladder with field cancerization. Therapeutic approaches are very challenging and the requirement to evaluate alternative therapeutic protocols that may prolong survival times in dogs bearing these tumours is compelling. We assessed the immunohistochemical expression of HER‐2 in 23 cases of canine TCCs of the urinary bladder and compare it with non‐neoplastic urothelium in order to evaluate a rationale for targeted therapies and gene‐based vaccines. HER‐2 positivity was recorded in 13/23 (56%) neoplastic lesions. The receptor was significantly overexpressed in neoplastic than in non‐neoplastic samples (P = .015). According to our preliminary results, it would be of interest to further evaluate the role of HER‐2 in canine TCCs as a marker of malignancy and a therapeutic target for cancer vaccine and antibodies. Moreover, the significantly different overexpression of HER‐2 in TCCs than in non‐neoplastic urothelium further supports to investigate its role in the progression toward malignancy of non‐neoplastic lesions.  相似文献   
669.
AIM:To investigate the role of zinc finger protein 281 (ZNF281) in the proliferation of hepatocellular carcinoma (HCC) cells. METHODS:The mRNA expression levels of ZNF281 in peripheral blood mononuclear cells from 80 cases of healthy people and 206 cases of HCC patients were determined by real-time PCR. Statistical analysis were used to illustrate the relationship between the mRNA expression levels of ZNF281 in the peripheral blood mononuclear cells and the clinicopathologic parameters of HCC patients. Real-time PCR and Western blot were used to detect the mRNA and protein expression levels of ZNF281 in hepatoma cell lines and immortalized hepatocytes. The silencing of ZNF281 was conducted by transfection of small interfering RNA targeting ZNF281, and then the proliferation of HCC cells was analyzed by MTS assay. The DNA synthesis of HCC cells was tested by Cell-LightTM EdU Apollo®488 In Vitro Imaging Kit. The ability of colony formation of the HCC cells was measured by colony formation assay, and the ability of anchorage-indepen-dent growth was detected by soft agar test. RESULTS:The mRNA expression level of ZNF281 in the peripheral blood mononuclear cells from HCC patients was significantly increased compared with the healthy people, and the high expression level was positively correlated with tumor size, tumor stage and tumor vascular invasion. Concurrently, the expression level of ZNF281 in hepatoma cell lines was significantly higher than that in immortalized hepatocytes. More importantly, the silencing of ZNF281 inhibited the proliferation, DNA synthesis, colony formation and anchorage-independent growth of the HCC cells. CONCLUSION:ZNF281 promotes the proliferation of HCC cells.  相似文献   
670.
Dogs and cats of our society have outgrown their status as merely pets and are now considered our close companions and even family members. This shift in their roles has led to pet owners seeking improved preventative medicine for their four-legged friends. Subsequently, dogs and cats are living longer lives than ever before and developing more old-age-related diseases. One of the most devastating diseases of older animals is cancer. Once a veterinarian has detected cancer in a pet, pet owners seek advice on their next course of action. This article is intended to provide concise information regarding the diagnosis and treatment of intranasal tumors of the dog and cat. This article outlines the forms of nasal tumors that are the most common, the recommended imaging and biopsy techniques to diagnose the tumor, and the most appropriate treatments of them.  相似文献   
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