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Spontaneous malignant mesothelioma was found in a 104-week-old male Crj:CD(SD) rat. The tumor was scattered on the surface of the lung, heart, mediastinal pleura and thoracic wall and metastasized to the alveolar septa. Histopathologically, small flattened or cuboidal tumor cells proliferated with stroma, formed almost normal papillary structures and reacted positively to colloidal iron stain and immunohistochemical staining for mesothelin. Round hyalinous stromata were pronounced, which is a characteristic feature, and the possible reason for this is as follows; at first, a small amount of collagen fibers was formed in the center of the clusters of several tumor cells, and then the cell clusters expanded like balloons with an increase in the collagen fibers.  相似文献   
164.
Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.  相似文献   
165.
RNA silencing is a sequence-specific defense mechanism against viruses. As a counterdefense, viruses evolved silencing suppressors to interfere with host silencing. In analyses using protoplasts prepared from cultured cells (BY-2) and mesophyll cells of Nicotiana tabacum and N. benthamiana, viral suppressors differentially functioned in different cell types. This phenomenon has not been discussed in earlier papers on protoplast systems and RNA silencing. In investigations of the cellular activities of viral suppressors and their role in the RNA-silencing pathway, assays with host protoplasts offer many advantages and can complement other in planta assays such as Agrobacterium-mediated transient expression.  相似文献   
166.
The relationship between the growth of preantral and antral follicles and that of their oocytes in ovaries of domestic cats (Felis catus) was analyzed. Eight hundred and five pairs of follicles and oocytes from the ovaries of 51 female cats were collected, and only healthy and fresh follicles and oocytes with or without zona pellucida were used in this study. Immediately after collection, the diameters of follicles and their oocytes were measured. The relationship of the follicle diameter to the oocyte diameter was applied to four regression models and statistically analyzed. The best fitting model was found to be a hyperbolic regression (the coefficient of determination was 0.976 between the follicles and their oocytes with a zona pellucida, y=184x/(x+0.0738); the coefficient of determination was 0.983 between the follicles and their oocytes without a zona pellucida, y=122x/(x+0.0301)). The differentiated equations for the hyperbolic curves in the oocytes with or without a zona pellucida and the follicles were found to be y'=13.6/(x+0.0738)(2) and y'=3.67/(x+0.0301)(2), where y and x were the diameters of the oocytes (μm) and follicles (mm), respectively. When follicles grew to a size larger than 0.4 mm in diameter, the growth rates of their oocytes calculated by the differentiation equations showed an asymptotic depression around zero. Thus, it was suggested that when the follicles grew to a size larger than 0.4 mm in diameter, their oocytes reached full size and ceased to grow and that the zona pellucida stopped growing when the diameter of the follicles reached 0.3 mm in domestic cats.  相似文献   
167.
The secretion of prolactin (PRL) is under the dominant and tonic inhibitory control of dopamine (DA); however, we have recently found that salsolinol (SAL), an endogenous DA‐derived compound, strongly stimulated the release of PRL in ruminants. The aim of the present study was to clarify the inhibitory effect of DA on the SAL‐induced release of PRL in ruminants. The experiments were performed from late June to early July. Male goats were given a single intravenous (i.v.) injection of SAL (5 mg/kg body weight (BW)), a DA receptor antagonist (sulpiride, 0.1 mg/kg BW), or thyrotropin‐releasing hormone (TRH, 1 µg/kg BW) before and after treatment with a DA receptor agonist (bromocriptine), and the effect of DA on SAL‐induced PRL release was compared to that on sulpiride‐ or TRH‐induced release. Bromocriptine completely inhibited the SAL‐induced release of PRL (P < 0.05), and the area under the response curve (AUC) for a 120‐min period after the treatment with bromocriptine was 1/28 of that for before the treatment (P < 0.05). Bromocriptine also completely inhibited the sulpiride‐induced release (P < 0.05). The AUC post‐treatment was 1/17 that of pre‐treatment with bromocriptine (P < 0.05). Bromocriptine also inhibited the TRH‐induced release (P < 0.05), though not completely. The AUC post‐treatment was 1/3.8 that of pre‐treatment (P < 0.05). These results indicate that DA inhibits the SAL‐induced release of PRL in male goats, and suggest that SAL and DA are involved in regulating the secretion of PRL. They also suggest that in terms of the regulatory process for the secretion of PRL, SAL resembles sulpiride but differs from TRH.  相似文献   
168.
Yamada  Miwa  Yukita  Ai  Hanazumi  Yuta  Yamahata  Yuki  Moriya  Hiroki  Miyazaki  Masao  Yamashita  Tetsuro  Shimoi  Hitoshi 《Fisheries Science》2018,84(2):405-412
Fisheries Science - We isolated Burkholderia sp. AIU M5M02, which accumulates poly(3-hydroxybutyrate) [P(3HB)] homopolymer in a nitrogen-limiting mineral salt medium containing mannitol as a sole...  相似文献   
169.

Objective

To determine the effects of brimonidine tartrate ophthalmic solution on sedation, heart rate (HR), respiratory frequency (fR), rectal temperature (RT) and noninvasive mean arterial pressure (MAP) in healthy cats.

Study design

Randomized, blinded crossover study, with 1 week washout between treatments.

Animals

Six healthy purpose-bred cats.

Methods

Brimonidine tartrate ophthalmic solution 0.1% (one or two drops; 58.6 ± 3.3 μg per drop) or a control solution (artificial tear solution) was administered to six healthy cats. Behavioural observations and measurements of HR, fR, RT and MAP were recorded before and at 30, 60, 90, 120, 180, 240, 300 and 360 minutes after topical administration. Behavioural scores were analysed using Friedman’s test for repeated measures to evaluate the time effect in each treatment and treatment effect at each time point. Physiological variables (HR, fR, RT and MAP) were analysed using two-way analysis of variance for repeated measures to evaluate the time and treatment effects. The level of significance was set at p < 0.05.

Results

Dose-dependent behavioural and physiological responses were noted. A dose of two drops of brimonidine resulted in sedation in the cats and decreased HR and MAP. Significant sedative effects occurred between 30 and 120 minutes and for physiological responses up to 360 minutes. The most frequent adverse reaction was vomiting, occurring within 40 minutes in all six cats administered two drops and five of the six cats administered one drop of brimonidine.

Conclusions and clinical relevance

The results demonstrated that ocular administration of brimonidine 0.1% ophthalmic solution induced sedation in cats and some cardiovascular effects usually associated with α2-adrenoceptor agonists. Further studies should be performed to determine clinical applications for this agent in cats.  相似文献   
170.
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