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1.
A unique N-linked glycosylation motif (Asn79-Tyr-Thr) was found in the sequence of type-A feruloyl esterases from Aspergillus spp. To clarify the function of the flap, the role of N-linked oligosaccharides located in the flap region on the biochemical properties of feruloyl esterase (AwFAEA) from Aspergillus awamori expressed in Pichia pastoris was analyzed by removing the N-linked glycosylation recognition site by site-directed mutagenesis. N79 was replaced with A or Q. N-glycosylation-free N79A and N79Q mutant enzymes had lower activity than that of the glycosylated recombinant AwFAEA wild-type enzyme toward α-naphthylbutyrate (C4), α-naphthylcaprylate (C8), and phenolic acid methyl esters. Kinetic analysis of the mutant enzymes indicated that the lower catalytic efficiency was due to a combination of increased K m and decreased k cat for N79A, and to a considerably decreased k cat for N79Q. N79A and N79Q mutant enzymes also exhibited considerably reduced thermostability relative to the wild-type.  相似文献   
2.
A firm, mobile, oblong mass was discovered as an incidental finding in the stomach of a chimpanzee (Pan troglodytes) during routine surgery. It was removed and determined to be a trichobezoar.  相似文献   
3.
Summary Stridulation of grasshoppers is controlled by hemisegmental pattern generator subunits which probably are restricted to the metathoracic ganglion complex (TG3-complex). The coordination of left and right pattern generator subunits depends on commissures of the TG3-complex (Ronacher 1989). The coordination of the stridulatory movements was studied in Chorthippus dorsatus males with partial mediosagittal incisions in the TG3-complex.Animals bearing anterior incisions in the TG3-complex, by which all commissures of the metathoracic neuromere and the first abdominal neuromere were transected, were still able to produce bilaterally coordinated species-specific stridulatory movements. Commissures of the T3- and A1-neuromere, thus, are not necessary, and the A2-, A3-commissures are sufficient for this coordination (Figs. 3, 4).Animals with partial posterior incisions, extending until A1, had deficits in their stridulation pattern; the coordination between the hindlegs was impaired though not completely lost (Fig. 6). This is discussed in view of the structure of stridulation interneurons identified in a related grasshopper species (Omocestus viridulus).These results indicate an unexpected substantial contribution of the abdominal neuromeres A2 and A3 to the control of stridulatory movements. This constitutes an interesting parallel to the flight control system of locusts where interneurons located in the first 3 abdominal neuromeres also appear to contribute to the flight pattern generator (Robertson et al. 1982).Abbreviations A1–A3 abdominal neuromeres 1–3 - T3 metathoracic neuromere - TG3-complex metathoracic ganglion complex including A1–A3  相似文献   
4.
Intracellular recordings and dye injections were used to examine mutual coupling among slow abdominal postural motoneurons in the 4th abdominal ganglion in crayfish (Procambarus clarkii). Intracellular current injection into one motoneuron altered the spike firing rate of some of its synergists. Depending on the polarity of the injected current, the premotor effect on the synergists was excitatory or inhibitory. The magnitude of the effect was intensity dependent. No dye coupling was found among the motoneurons following injection of Lucifer yellow. The morphological basis of the coupling was examined by differential filling of motoneuron pairs, one with horseradish peroxidase and the other with Lucifer yellow. The stained motoneurons were simultaneously visualized under light microscopy to determine the proximity of their differently colored dendrites. It was thus possible to locate the site of the presumed monosynaptic contacts between them. Combined physiological and morphological evidence suggests that these neurons are mutually coupled, forming part of an integrative system for abdominal posture control in crayfish.  相似文献   
5.
摘要 目的:探讨腹式呼吸训练联合短刺法针刺对气滞血瘀型腰椎间盘突出症(LDH)患者康复效果的影响。方法:将2020年1月至2022年6月湖南中医药大学第一附属医院收治的478例气滞血瘀型LDH患者,随机数字表法分为两组,对照组239例患者实施短刺法针刺治疗,观察组239例患者行腹式呼吸训练联合短刺法针刺治疗。比较两组治疗效果、治疗前后中医症候评分、肌电值(坐位、直立位、前屈位、后伸位)、疼痛因子水平[前列腺素E2(PGE2)、β-内啡肽(β-EP)、5-羟色胺(5-HT)、P物质(SP)]水平、视觉模拟量表(VAS)评分、Oswestry功能障碍指数(ODI)、日本骨科协会评估治疗分数(JOA)评分、腰椎关节活动度(左屈、左旋、右屈、右旋)及安全性。结果:治疗后,两组治疗效果分级经秩和检验差异具有统计学意义(P<0.05),且观察组治疗总有效率显著高于对照组(P<0.05)。治疗后观察组各中医症候评分低于对照组(P<0.05)。治疗后观察组坐位、直立位、前屈位、后伸位肌电值高于对照组(P<0.05)。治疗后观察组疼痛因子PGE2、5-HT、SP水平低于对照组,β-EP水平高于对照组(P<0.05)。治疗后观察组VAS评分、ODI低于对照组,JOA评分高于对照组(P<0.05)。治疗后观察组左屈、左旋、右屈、右旋活动度优于对照组(P<0.05)。两组不良事件发生率比较无显著差异(P>0.05)。结论:腹式呼吸训练联合短刺法针刺可提高气滞血瘀型LDH患者临床疗效,增强患者肌力,改善腰椎功能,恢复关节活动度,同时通过调控疼痛介质水平,减轻患者疼痛症状,且具有较好安全性,值得临床借鉴应用。  相似文献   
6.
K J Simansky  G P Smith 《Peptides》1983,4(2):159-163
Rats were tested two or three days after bilateral abdominal vagotomy or a laparotomy control procedure for their drinking responses to subcutaneous (1 mg-kg-1) or intracerebroventricular (100 ng) injections of angiotensin II. Vagotomy delayed the initiation of drinking and decreased 60-min water intake after subcutaneous, but not after intracerebroventricular, angiotensin II. This is the shortest postoperative interval in which the decrease in drinking after systemic injection of angiotensin II by abdominal vagotomy has been observed. The failure of vagotomy to decrease the response to intracerebroventricular angiotensin II demonstrates that the deficit after subcutaneous injection was not a nonspecific effect of recent vagotomy. These results, therefore, suggest that the abdominal vagus is necessary for normal drinking in response to circulating angiotensin II. Furthermore, the selective and acute onset of the deficit is consistent with the loss of a specific, rather than tonic facilitatory, vagal mechanism for drinking after elevation of circulating angiotensin II levels. Finally, the results imply that the physiological mechanisms which mediate the drinking responses to central and peripheral angiotensin are not identical.  相似文献   
7.
Summary Ovaries from 4-day-old female adults of Gryllus bimaculatus produce about 5 ng of free and conjugated ecdysteroids per hour during a 16-h incubation in Grace's medium. During incubation of pieces of the abdominal integument together with the adjacent segmental fat body, a net synthesis of moulting hormones is observed (2.3 ng per hour per animal), similar to that in the ovary. Separate incubations of disunited abdominal epidermis and segmental fat body tissue result in much lower rates of ecdysteroid synthesis. Ecdysteroid synthesis in ovarian homogenates is about one-third of that in intact organs. This reduction is due to a lack of conjugate formation in homogenates. Homogenates of the abdominal integument complex are no longer capable of synthesizing ecdysteroids. For both tissues, a de novo synthesis of ecdysteroids is corroborated by following the in vitro incorporation of [14C]-label from cholesterol and [3H]-label from 2,22,25-trideoxyecdysone (5-ketodiol), respectively, into free ecdysone. The rate of incorporation into ecdysone is only 0.0014% for cholesterol but 0.48% for 5-ketodiol. Both tissues represent primary sources of ecdysteroids in female adult crickets.Abbreviations HPLC high performance liquid chromatography - IU international units - NP normal phase - RIA radioimmunoassay - RP reversed phase - SEM standard error of mean  相似文献   
8.
Summary The research presented here was designed to investigate the mode of inheritance of fat and lean tissue deposition, and the relationship between them and body weight in Japanese quail. Heterotic effects were found for weight, size, and number of adipocytes in the abdominal fat depots, weight of the sartorial fat depot and percentage carcass fat with means for the hybrids being lower than those for the parental lines. General inferences concerning the importance of nonadditive genetic variation for lean and body weight were precluded due to inconsistencies observed among mating combinations. Thus, although heterosis and recombination effects were general for characteristics associated with fat deposition, the situation for body weight and lean was unique to the populations involved. It may be hypothesized that heterosis in the efficiency of feed utilization is reflected by the heterosis for fat deposition which explains why hybrids utilize feed better than their parental lines.  相似文献   
9.
Flap endonuclease 1 (FEN1) has emerged as an important enzyme in the maintenance of genomic instability and preventing carcinogenesis. The relationship between FEN1 −69G>A (rs174538)+4150G>T (rs4246215) polymorphisms and cancer susceptibility has been reported; however, results were inconclusive. In the present study, a meta-analysis of data from eligible reports was carried out to summarize the possible relationship between FEN1 polymorphisms and cancer risk. A total of 11 articles, including 20 studies with 7366 cases and 9028 controls and 18 studies with 6649 cases and 8325 controls for FEN1 rs174538 and FEN1 rs4246215 polymorphisms, respectively, were recruited for meta-analysis. Overall, meta-analyses showed that FEN1 rs174538 and rs4246215 polymorphisms are significantly associated with the decreased risk of cancer. The stratified analysis proposed that both variants were associated with protection against gastrointestinal cancer, breast cancer, hepatocellular cancer, esophageal cancer, gastric cancer, colorectal cancer, and lung cancer. In conclusion, this meta-analysis revealed an association between FEN1 polymorphisms and cancer risk. Additional studies in a larger study population that include subjects from a variety of ethnicities are warranted to further verify our findings.  相似文献   
10.
Gallstone ileus is a rare and potentially serious complication of cholelithiasis. It is defined as a mechanical intestinal obstruction secondary to the presence of a gallstone in the intestinal luz. The most frequent cause is impaction of the calculus in the ileum after passing through a bilioenteric fístula. It has a high morbidity and mortality rate, mainly due to the difficulty and delay in its diagnosis. A retrospective study is presented of 4 cases of gallstone ileus treated between 2013 and 2017 in the Hospital Nuestra Señora del Prado. An analysis was performed on the clinical characteristics, diagnostic tests, and surgical treatment.  相似文献   
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