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141.
Decubital shoulder ulcers are lesions on the shoulders of sows kept in production systems, reported to have a relatively high prevalence, and to some extent be comparable with human pressure ulcers. In sows, the ulcers are caused by pressure inflicted by the flooring, leading to oxygen deficiency in the skin and the underlying tissue. This paper reviews existing knowledge about decubital shoulder ulcers in sows, focusing on the pathogenesis, classification and consequences in terms of pain and animal welfare. On the basis of available human as well as animal literature, we describe the primary causal factors, underlying mechanisms, suggested direction of progression as well as temporal development. We review suggested scales for the classification of decubital shoulder ulcers, and argue that none of these are useful for the classification of decubital shoulder ulcers in live sows. The knowledge of the welfare consequences of decubital shoulder ulcers is limited. On the basis of the tissue structures that are involved, we assume that the development and presence of decubital shoulder ulcers in sows are a painful and prolonged condition. It is concluded that the extent of the welfare problem related to decubital shoulder ulcers cannot be fully determined until a valid ante-mortem classification system is available, and knowledge about the duration of the condition (including the various stages), as well as the possible consequences in terms of pain or discomfort have been established.  相似文献   
142.
本文对出土于宁夏东汉时期的石砚子墓地中一例罕见颅骨病理性损伤个体进行了古病理学诊断分析,该男性个体颅骨上可见不规则形大面积骨质破坏,累及额骨、左侧顶骨、左侧颞骨以及右侧顶骨,缺损周缘可见成骨性、溶骨性反应混合特征,呈向内、外翻卷状,边缘伴有骨膜反应,颅内壁可见较深血管压迹。通过CT影像分析骨骼损伤形态、骨骼损伤区域特征,并结合临床医学资料进行鉴别诊断,排除了朗格汉斯细胞组织细胞增生症、骨血管瘤、Gorham-Stout综合征、骨髓瘤和非特异性感染,推测该病例的病理诊断为甲状腺癌导致的继发性颅骨转移癌。  相似文献   
143.
《朊病毒》2013,7(3):223-233
Aggregation-prone proteins associated with neurodegenerative disease, such as α synuclein and β amyloid, now appear to share key prion-like features with mammalian prion protein, such as the ability to recruit normal proteins to aggregates and to translocate between neurons. These features may shed light on the genesis of stereotyped lesion development patterns in conditions such as Alzheimer disease and Lewy Body dementia. We discuss the qualifications of tau protein as a possible “prionoid” mediator of lesion spread based on recent characterizations of the secretion, uptake and transneuronal transfer of human tau isoforms in a variety of tauopathy models, and in human patients. In particular, we consider (1) the possibility that prionoid behavior of misprocessed tau in neurodegenerative disease may involve other aggregation-prone proteins, including PrP itself, and (2) whether “prionlike” tau lesion propagation might include mechanisms other than protein-protein templating.  相似文献   
144.
N. Izadi‐Mood, S. Sarmadi and S. Sanii
Quality control in cervicovaginal cytology by cytohistological correlation Objective: Frequent studies attest to the correlation of cytological interpretations with defined histopathological entities. Nevertheless, as part of quality control, cytology laboratories are required to compare Papanicolaou smear reports with those of cervical biopsies to search for discrepancies. We have attempted to determine and categorize the causes of existing discrepancies in our laboratory in order to clarify the source of errors. Methods: We reviewed 670 cervical smears that were paired with subsequent punch biopsy or endocervical curettage samples, obtained within 2 months of the cytology, and found out that 60 smear‐biopsy pairs were discrepant regarding the diagnosis. These cases were categorized into four error groups after careful re‐evaluation of the original smear and biopsy slides. Results: In 51 (85%) of 60 cervical smear‐biopsy pairs with reports that disagreed, the initial diagnoses of both cervical smear and biopsy were confirmed by the review opinion; in these cases, cytology and biopsy ‘sampling errors’ were responsible for 40 and 11 instances of discrepancy, respectively. Seven cases (11.1%) were discrepant due to ‘smear interpretation errors’ and consisted of five cases with initial under‐diagnosis and two cases with initial over‐diagnosis. One case (1.7%) was due to ‘screener error’. In another case, discordance was due to cervical ‘biopsy interpretation error’, with initial over‐diagnosis as squamous intraepithelial lesion. Conclusion: In this retrospective study, we determined the causes of cytohistological discrepancies in cervical samples. The main explanation for discrepancy was ‘sampling error’.  相似文献   
145.
Oral mucoceles are the most common benign minor salivary gland lesions. It is of interest to document the prevalence of oral mucocele among outpatients at the Saveetha Dental Hospital, India. We used patient data (12 case records) with mucocele occurrence for this analysis. Data included age, gender, diagnosis, lesion duration and relevant dental history. Data shows that oral mucocele were seen predominantly in males (66%) when compared to females (34%). The most affected site in the oral cavity was the lower lip (58%). Thus, data shows that oral mucocele was predominantly seen in males compared to females. Data also shows that the lower lip is often affected.  相似文献   
146.
Determining best practices for managing free farrowing systems is crucial for uptake. Cross-fostering, the exchange of piglets between litters, is routinely performed amongst crate-housed sows. However, cross-fostering can increase fighting amongst the litter and may be more challenging within free farrowing systems as sows have more freedom to respond to cross-fostered piglets. This study compared the effect of either cross-fostering (FOS), or a control of sham-fostering (CON), of four focal piglets per litter on Day 6 postpartum in crates (CRATE) and free farrowing pens (PEN). The post-treatment behavioural responses of sows were recorded (Day 6 = 60 min; Day 7 = 300 min; n = 48), as were the average daily gain (ADG; g/day), total weight gain (TWG; kg) and body lesion scores of focal piglets and their littermates throughout lactation (Day 6, Day 8, Day 11 and Day 26; n = 539) and the post-weaning period (Day 29, Day 32 and Day 60; n = 108). On Day 6, though post-reunion latency to nursing did not differ, latency to successful nursing was longer amongst FOS than CON litters (P < 0.001), more so amongst CRATE FOS than PEN FOS (P < 0.01). On Day 7, PEN FOS sows had fewer successful nursing bouts (P < 0.05) and exhibited decreased lateral (P < 0.01) and increased ventral lying frequencies (P < 0.01) compared to all other housing and treatment combinations. Focal piglet ADG was lower for FOS than CON in the CRATE during Day 6 to Day 8 (P < 0.01) and lower in the PEN during Day 6 to Day 8 (P < 0.001), Day 8 to Day 11 (P < 0.01) and Day 11 to Day 26 (P < 0.05). The TWG of pre-weaned focal piglets (Day 6 to Day 26) was higher amongst CON than FOS litters (P = 0.01). Post-weaning, piglet ADG was higher for PEN than CRATE during Day 26 to Day 29 (P < 0.01) and higher for FOS than CON during Day 26 to Day 29 (P < 0.05), Day 29 to Day 32 (P < 0.001) and Day 32 to Day 60 (P < 0.01); thus, TWG was higher for FOS than CON during the weaner (P = 0.001) and the combined lactation and weaner periods (P = 0.09). In conclusion, sow behaviour was disrupted by cross-fostering in the crates and pens and continued to be disturbed on the following day amongst penned sows. FOS piglets exhibited reduced ADG after cross-fostering, which extended throughout lactation in the pens. However, the increased post-weaning weight gain of FOS piglets meant that their TWG was higher than CON piglets, irrespective of the farrowing system used.  相似文献   
147.
Class II photolyases ubiquitously occur in plants, animals, prokaryotes and some viruses. Like the distantly related microbial class I photolyases, these enzymes repair UV-induced cyclobutane pyrimidine dimer (CPD) lesions within duplex DNA using blue/near-UV light. Methanosarcina mazei Mm0852 is a class II photolyase of the archaeal order of Methanosarcinales, and is closely related to plant and metazoan counterparts. Mm0852 catalyses light-driven DNA repair and photoreduction, but in contrast to class I enzymes lacks a high degree of binding discrimination between UV-damaged and intact duplex DNA. We solved crystal structures of Mm0852, the first one for a class II photolyase, alone and in complex with CPD lesion-containing duplex DNA. The lesion-binding mode differs from other photolyases by a larger DNA-binding site, and an unrepaired CPD lesion is found flipped into the active site and recognized by a cluster of five water molecules next to the bound 3'-thymine base. Different from other members of the photolyase-cryptochrome family, class II photolyases appear to utilize an unusual, conserved tryptophane dyad as electron transfer pathway to the catalytic FAD cofactor.  相似文献   
148.
In positive serial conditional discrimination, animals respond during a target stimulus when it is preceded by a feature stimulus, but they do not respond when the same target stimulus is presented alone. Moreover, the feature and target stimuli are separated from each other by an empty interval. The present work aimed to investigate if two durations (4 or 16 s) of the same feature stimulus (light) could modulate the operant responses of rats to different levers (A and B) during a 5-s target stimulus (tone). In the present study, lever A was associated with the 4-s light, and lever B was associated with the 16-s light. A 5-s empty interval was included between the light and the tone. In the same training procedure, the rats were also presented with the 5-s tone without the preceding light stimuli. In these trials, the responses were not reinforced. We evaluated the hippocampal involvement of these behavioral processes by selectively lesioning the dentate gyrus with colchicine. Once trained, the rats were submitted to a test using probe trials without reinforcement. They were presented with intermediate durations of the feature stimulus (light) to obtain a temporal bisection curve recorded during the exposure to the target stimuli. The rats from both groups learned to respond with high rates during tones preceded by light and with low rates during tones presented alone, which indicated acquisition of the serial conditional discrimination. The rats were able to discriminate between the 4- and 16-s lights by correctly choosing lever A or B. In the test, the temporal bisection curves from both experimental groups showed a bisection point at the arithmetic mean between 4 and 16 s. Such processes were not impaired by the dentate gyrus lesion. Thus, our results showed that different durations of a feature stimulus could result in conditional properties. However, this processing did not appear to depend on the dentate gyrus alone.  相似文献   
149.
We conducted gross and microscopic characterizations of lesions in Cnidaria from Palmyra Atoll, Central Pacific. We found growth anomalies (GA) to be the most commonly encountered lesion. Cases of discoloration and tissue loss were rare. GAs had a focal or multi-focal distribution and were predominantly nodular, exophytic, and umbonate. In scleractinians, the majority of GAs manifested as hyperplasia of the basal body wall (52% of cases), with an associated absence or reduction of polyp structure (mesenteries and filaments, actinopharynx and tentacles), and depletion of zooxanthellae in the gastrodermis of the upper body wall. In the soft corals Sinularia sp. and Lobophytum sp., GAs exclusively manifested as prominent hyperplasia of the coenenchyme with an increased density of solenia. In contrast to scleractinians, soft coral GAs displayed an inflammatory and necrotizing component with marked edema of the mesoglea, accompanied by infiltrates of variably-sized granular amoebocytes. Fungi, algae, sponges, and Crustacea were present in some scleractinian GAs, but absent in soft coral GAs. Fragmentation of tissues was a common finding in Acropora acuminata and Montipora cf. dilatata colonies with tissue loss, although no obvious causative agents were seen. Discoloration in the zoanthid, Palythoa tuberculosa, was found to be the result of necrosis, while in Lobophytum sp. discoloration was the result of zooxanthellar depletion (bleaching). Soft corals with discoloration or tissue loss showed a marked inflammatory response, however no obvious causative organisms were seen. Lesions that appeared similar at the gross level were revealed to be distinct by microscopy, emphasizing the importance of histopathology.  相似文献   
150.
M. Ueno    A. Imaoka    J. Kihara    S. Arase 《Journal of Phytopathology》2007,155(4):228-235
The effective wavelength of light on Sekiguchi lesion formation, tryptamine accumulation, enzyme activities and hydrogen peroxide (H2O2) generation involved in light‐induced resistance of rice (cv. Sekiguchi‐asahi) infected with Magnaporthe grisea was determined by using band‐pass filters (BPF). When the M. grisea‐inoculated leaves were irradiated by BPF‐filtered lights from daylight fluorescent lamps, Sekiguchi lesion development was enhanced by increasing the wavelength of visible light. The longer the radiation wavelength, the greater the tryptamine accumulation, the tryptophan decarboxylase and monoamine oxidase activities, and the H2O2 generation. By contrast, the longer the radiation wavelength of radiation, the greater the inhibition of catalase (CAT) activity. Among the visible lights, red light was the most effective for tryptamine pathway activation and CAT inhibition involved in light‐induced resistance.  相似文献   
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