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51.
肺部炎性假瘤(附28例误诊分析)   总被引:1,自引:0,他引:1  
1978年9月至1994年7月,我科对肺炎性假瘤30例施行手术治疗,术前误诊高达28例,占93.3%。30例中男21例,女9例,平均年龄53.4岁,这与文献报道有显著不同。本文从IPL临床表现,X线征象及手术所见等方面对可引起误诊的因素进行了仔细分析。提出了减少误诊的措施,并对IPL的预防和治疗作了讨论。  相似文献   
52.
【目的】了解猪圆环病毒2型(PCV-2)感染对PK-15细胞抗病毒相关因子转录时相的影响,探讨宿主-病毒之间的作用关系。【方法】运用荧光定量PCR技术,测定和分析PCV-2感染PK-15细胞后0(未接种病毒),1,6,12,24,48,72 h时病毒DNA含量及细胞因子IFN-βI、FN-γI、FNAR-1I、FNAR-2、MHC-Ⅰ、MHC-Ⅱ、MX1、NOS、RNaseL和IRF-3 mRNA转录水平的变化。【结果】PCV-2感染PK-15后1 h就可以检测到病毒DNA,在感染后24 h病毒开始大量迅速增殖,于感染72 h时达到最高峰。与0 h相比,PCV-2感染后IFN-βI、RF-3的表达量在感染12 h时显著增加,其他时间表达量下降;IFN-γ、MHC-Ⅱ的表达量在感染12 h时增加不明显,其他时间表达量下降;感染PCV-2后IFNAR-2、MHC-Ⅰ、MX1的表达量下降;RNaseL的表达量在感染12 h时显著减少,其他时间表达量增加,48 h时表达量增加显著;IFNAR-1的表达量在感染72 h时显著增加,其他时间表达量下降;未检测出NOS的表达。【结论】随着PCV-2病毒含量的增加,以上几种主要抗病毒因子的表达量不明显或有所下降,表明PCV-2感染PK-15细胞后可逃避机体的抗病毒作用机制。  相似文献   
53.
The purpose of our study was to investigate changes in immunological parameters induced by weaning stress (including milk restriction) in calves. Fifteen Holstein calves were subjected to weaning at 6 weeks of age. Blood samples were collected at -14, -7, -2, 1, 3, and 5 days post-weaning (DPW; 0 DPW = 42 days). Weaning caused significant (p < 0.01) increases in the neutrophil (NE):lymphocyte (LY) ratio at 5 DPW with a significant (p < 0.05) reduction of LYs. The concentration of acute-phase proteins (haptoglobin and serum amyloid A) also increased significantly (p < 0.05) at 3 and 5 DPW compared to -2 DPW. Levels of the iron-binding protein lactoferrin decreased significantly (p < 0.05) after weaning. Serum tumor necrosis factor-α and cortisol levels were elevated (p < 0.05) at 3 DPW, while those of serum interferon-γ decreased (p < 0.05) at 1 and 3 DPW compared to levels observed before weaning. Weaning significantly (p < 0.05) decreased the percentage of CD25+ T cells in the peripheral blood. In conclusion, weaning stress affected the NE:LY ratio along with the levels of acute phase proteins, lactoferrin, cortisol, and inflammatory cytokines in the peripheral blood of calves. Weaning stress may induce an acute phase response possibly through the elevation of cortisol production and modulation of inflammatory cytokines.  相似文献   
54.
ObjectiveTo determine the lowest efficacious dose of oral meloxicam for relieving pain in cats with a sodium urate (SU)-induced acute inflammatory synovitis.Study designRandomized, blinded, controlled, and four-way crossover study.AnimalsEight surgically neutered cats (four males, four females) paired according to sex.MethodsEach pair of cats was treated with 0 (placebo), 0.025, 0.05, or 0.075 mg kg?1 oral meloxicam once daily for 4 days prior to injection, into alternating stifles, of 1 mL of 20 mg mL?1 SU crystals, beginning with the right stifle. Each cat received each of the four treatments, separated by at least 21 days. Analgesic efficacy was evaluated based on objective (e.g., pressure mat data total force, contact pressure, and contact area) and subjective (e.g., scores for Analgesia Scale [AS], Lameness Scale [LS], and Visual Analog Scale [VAS]) outcome measures for pain assessment. All outcome measures were recorded before and during 30 hours after SU injection. The pre-defined primary outcome measure was the area under the response–time curve (AUC0–30 hours) of the total force of the injected limb. Data were analyzed by analysis of variance. A sequential test procedure was applied and the test sequence stopped in case of a nonsignificant result.ResultsMeloxicam at doses of 0.05 and 0.075 mg kg?1 day?1 PO was significantly different from placebo for the pre-defined primary outcome measure (i.e., AUC0–30 hours of total force). All tested meloxicam doses were lower than placebo for the subjective outcome measures (i.e., AUC0–30 hours of AS, LS, and VAS).Conclusions and clinical relevanceThe lowest efficacious dose of meloxicam for relieving pain in cats with an SU-induced synovitis was 0.05 mg kg?1 day?1 PO according to the pre-defined primary outcome measure. However, lower doses may also be effective as seen in the subjective outcome measures.  相似文献   
55.
The purpose of this study was to determine the impact of the non-steroidal anti-inflammatory drug tepoxalin on canine tumour cell growth and describe the changes associated with tepoxalin treatment. In vitro experiments were performed to assess tepoxalin-associated alterations in tumour cell growth. Clinically achievable tepoxalin concentrations did not significantly alter tumour cell growth in vitro. Vascular endothelial growth factor (VEGF) production and hypoxia-inducible factor-1α dose-dependently increased in vitro in the presence of tepoxalin. A canine osteosarcoma xenograft was used to determine in vivo effects of tepoxalin on tumour growth and angiogenesis. Despite increased VEGF in vitro, there was a significant growth delay associated with tepoxalin treatment. Normal dogs were administered tepoxalin to assess effects on systemic VEGF production, but not found to have significantly increased VEGF. These data suggest that tepoxalin may moderately inhibit tumour growth and may be administered as an analgesic to tumour-bearing dogs.  相似文献   
56.
BACKGROUND: The cytologic diagnosis of ear canal tumors is difficult or impossible by swab alone because cell exfoliation may be poor and neoplastic cells may be masked by associated inflammation. Fine-needle biopsy (FNB) can be used to obtain a higher yield of cells for diagnosis. OBJECTIVE: The purpose of this study was to assess the efficacy and diagnostic value of FNB and cytologic examination in providing an accurate diagnosis of masses growing in the external ear canal of cats. METHODS: Cytologic specimens from masses in the external ear canal, taken under inhaled, general anesthesia, were classified into 4 groups: 1) ceruminous gland hyperplasia or adenoma, 2) ceruminous gland adenocarcinoma, 3) inflammatory polyps, and 4) other neoplastic and non-neoplastic masses. Cytopathologic diagnoses were compared with the final histopathologic diagnoses, and indices of diagnostic test accuracy (sensitivity, specificity, likelihood ratios, diagnostic-odds ratios) were calculated. RESULTS: Twenty-seven masses (from 25 cats, including 2 cats affected bilaterally) were included in the study. The results showed good correspondence between cytologic and histologic diagnoses with an overall agreement index (kappa) of .74, a diagnostic odds ratio of 22, and 100% (27/27) agreement in the diagnosis of inflammatory polyps versus neoplasia (both benign and malignant). CONCLUSIONS: FNB cytopathology of external ear masses in the cat was sufficiently accurate for distinguishing inflammatory polyps from neoplasia. For differentiation of benign proliferation and malignant neoplasia, however, histopathologic confirmation is recommended.  相似文献   
57.
Immunopathology of Chlamydophila abortus infection in sheep and mice   总被引:3,自引:0,他引:3  
Chlamydophila abortus targets the placenta, causing tissue damage, inflammation and abortion (enzootic abortion of ewes). It is one of the main infectious causes of abortion in ewes, resulting in major economic losses to agricultural industries worldwide. Although ruminants and pigs are the principal hosts, humans are also susceptible to infection. Control of disease requires a host inflammatory response, which is likely to contribute to pathology and abortion. Mouse models have been widely used to provide insight into the role of specific immune cells in controlling infection and disease. The use of such model systems for investigating the mechanisms of abortion, latency, persistence, and immunity to reinfection will result in the identification of novel vaccine control strategies for sheep.  相似文献   
58.
59.
The intestine is the primary organ responsible for digestion and absorption of nutrients and is frequently subjected to external environmental stimulations leading to the development of inflammatory bowel disease (IBD), which can cause serious harm to intestinal health in animals. Dietary amino acids play important roles in promoting intestinal development and maintaining intestinal health and exert diverse effects through multiple signaling pathways on the prevention and treatment of IBD, including affecting the physiological activities of intestinal epithelial cells, improving intestinal barrier function, reducing intestinal oxidative damage, regulating the production of inflammatory cytokines, and promoting the expression of endogenous antimicrobial peptides, and involved in main signaling pathways including AMP-activated kinase (AMPK), mammalian target of rapamycin (mTOR), mitogen-activated protein kinase (MAPK), Toll-like receptors (TLRs), nucleotide binding oligomerization domain (NOD)/nuclear factor kappa-B (NF-κB). In this review, basic characteristics of IBD, effects and involved signaling pathways of the amino acids on IBD, and effects and applications of amino acids in maintaining intestinal health in livestock and poultry production were reviewed, so as to provide effective clues and strategies for dietary nutrients in the prevention and treatment of IBD.  相似文献   
60.
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