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111.
目的:比较腹腔镜阑尾切除术和开腹阑尾切除术治疗急性阑尾炎的临床疗效。方法:选取2012年3月-2014年3月我院收治的急性阑尾炎患者127例,按照随机数字表法分为两组,观察组63例行腹腔镜阑尾切除手术,对照组64例行开腹阑尾切除手术,比较两组的手术效果及术后并发症情况。结果:两组的手术时间差异无统计学意义(P0.05),观察组术中出血量、肛门排气时间及住院时间均低于对照组,差异有统计学意义(P0.05)。两组治疗后VAS评分较治疗前有不同程度的降低,且观察组低于对照组,差异有统计学意义(P0.05)。观察组切口感染、肠梗阻以及腹腔脓肿发生率均低于对照组,差异有统计学意义(P0.05),而两组腹腔内出血、阑尾残端瘘的发生率比较,差异无统计学意义(P0.05)。结论:腹腔镜阑尾切除术治疗急性阑尾炎具有手术效果好、预后快及术后并发症少等特点,值得临床推广使用。 相似文献
112.
Lortat-Jacob H Burhan I Scarpellini A Thomas A Imberty A Vivès RR Johnson T Gutierrez A Verderio EA 《The Journal of biological chemistry》2012,287(22):18005-18017
Heparan sulfate proteoglycans are critical binding partners for extracellular tranglutaminase-2 (TG2), a multifunctional protein involved in tissue remodeling events related to organ fibrosis and cancer progression. We previously showed that TG2 has a strong affinity for heparan sulfate (HS)/heparin and reported that the heparan sulfate proteoglycan syndecan-4 acts as a receptor for TG2 via its HS chains in two ways: by increasing TG2-cell surface trafficking/externalization and by mediating RGD-independent cell adhesion to fibronectin-TG2 matrix during wound healing. Here we have investigated the molecular basis of this interaction. Site-directed mutagenesis revealed that either mutation of basic RRWK (262-265) or KQKRK (598-602) clusters, forming accessible heparin binding sequences on the TG2 three-dimensional structure, led to an almost complete reduction of heparin binding, indicating that both clusters contribute to form a single binding surface. Mutation of residues Arg(19) and Arg(28) also led to a significant reduction in heparin binding, suggesting their involvement. Our findings indicate that the heparin binding sites on TG2 mainly comprise two clusters of basic amino acids, which are distant in the linear sequence but brought into spatial proximity in the folded "closed" protein, forming a high affinity heparin binding site. Molecular modeling showed that the identified site can make contact with a single heparin-derived pentasaccharide. The TG2-heparin binding mutants supported only weak RGD-independent cell adhesion compared with wild type TG2 or mutants with retained heparin binding, and both heparin binding clusters were critical for TG2-mediated cell adhesion. These findings significantly advance our knowledge of how HS/heparin influences the adhesive function of TG2. 相似文献
113.
Three ternary zinc complexes of the open chain polycarboxylic acid, tricarballylic (1,2,3-propane-tricarboxylic) acid (PTCH3) have been isolated and characterized with crystallographic and physicochemical techniques. [Zn(PTCH)(phen)(H2O)]2 · 4H2O (1) (where phen = 1,10-phenanthroline) has a unique dinuclear structure, while [Zn(PTCH)(bpy)]n · 3nH2O (2) and [Zn(PTCH)(epy)]n · 4nH2O (3) (where bpy = 4,4′-bipyridine and epy = 1,2-bis(4-pyridine)ethane) have 2D polymeric structures. The bis-deprotonated ligand, in all three complexes, uses for coordination only two oxygen atoms, which belong to the same carboxylate in 1, and to two different carboxylates in 2 and 3. 相似文献
114.
Chung HJ Jung JD Park HW Kim JH Cha HW Min SR Jeong WJ Liu JR 《Plant cell reports》2006,25(12):1369-1379
The complete nucleotide sequence of the chloroplast genome of potato Solanum tuberosum L. cv. Desiree was determined. The circular double-stranded DNA, which consists of 155,312 bp, contains a pair of inverted repeat regions (IRa, IRb) of 25,595 bp each. The inverted repeat regions are separated by small and large single copy regions of 18,373 and 85,749 bp, respectively. The genome contains 79 proteins, 30 tRNAs, 4 rRNAs, and unidentified genes. A comparison of chloroplast genomes of seven Solanaceae species revealed that the gene content and their relative positions of S. tuberosum are similar to the other six Solanaceae species. However, undefined open reading frames (ORFs) in LSC region were highly diverged in Solanaceae species except N. sylvestris. Detailed comparison was identified by numerous indels in the intergenic regions that were mostly located in the LSC region. Among them, a single large 241-bp deletion, was not associated with direct repeats and found in only S. tuberosum, clearly discriminates a cultivated potato from wild potato species Solanum bulbocastanum. The extent of sequence divergence may provide the basis for evaluating genetic diversity within the Solanaceae species, and will be useful to examine the evolutionary processes in potato landraces. 相似文献
115.
Wen-hua ZHAO ;Shi-biao YANG ;Jian-qiang HAN ;Mei JIANG ;Hua-chun LI ;Nian-zu ZHANG ;Qi-han LI 《Virologica Sinica》2009,(6):573-578
This paper reports the confirmed diagnosis by nested RT-PCR of PPR cases in Tibet, China in 2007, and results of phylogenetic analysis. Results showed that the 11 tested samples were PPRV positive by nested RT-PCR, of which 2 samples were genetically close to the X7443 strain (Nigeria 75/1) of lineage I, and 3 samples close to the strain AY560591 (Sungri96) of linage IV with 96.6%, 97.3%, 97.6% and 98% nucleotide sequence homogeneity respectively, based on partial sequencing of the F gene from 5 samples and complete sequencing of the N/M/F/H genes from one sample. This study suggested that there are at least 2 origins of PPRV in China. 相似文献
116.
A.N. Al Yacoub 《Theriogenology》2010,73(8):1018-1023
This investigation addresses the question whether it is possible to apply the open pulled straw (OPS) vitrification method, found to be effective for cryopreserving caprine (Capra aegagrus hircus) blastocysts, to other embryonal stages. Morulae, blastocysts and hatched blastocysts were cryopreserved by way of OPS vitrification and blastocysts and hatched blastocysts by conventional freezing. Morulae were not included with conventional freezing because in our experience the survival rate is very low. To assess the viability of the cryopreserved embryos, they were transferred to synchronized does; in most cases, two embryos per doe. After OPS vitrification, of nine does receiving morulae, not a single one became pregnant; of 11 does receiving blastocysts, nine (82%) became pregnant (all of which kidded and gave birth to, on average, 1.8 kids); and of nine does receiving hatched blastocysts, three (33%) became pregnant (two of which [22%] kidded, giving birth to a single kid each). After conventional freezing, of 10 does receiving blastocysts, five became pregnant (four of which [40%] carried to term and gave birth to a pair of twins each); and of nine does receiving hatched blastocysts, three (33%) became pregnant (and gave birth to a single kid each). Embryo survival (kids born/embryos transferred) after vitrification for morulae, blastocysts, and hatched blastocysts was 0, 70% (16 of 23), and 13% (2 of 16), respectively, and after conventional freezing for blastocysts and hatched blastocysts was 42% (8 of 19) and 19% (3 of 16), respectively. The difference in pregnancy and kidding rate between vitrified and conventionally frozen blastocysts was significant, and so was the difference in pregnancy rate between hatched and nonhatched blastocysts, regardless whether OPS-vitrified or conventionally frozen. The results of the current study indicate that OPS vitrification is a very effective means of cryopreserving caprine blastocysts. Unfortunately, the superiority of OPS vitrification over conventional freezing does not apply to caprine morulae and hatched blastocysts. 相似文献
117.
Rein U. Kirss 《Inorganica chimica acta》2004,357(11):3181-3186
The edge-bridged open ruthenocenes bis(η5-6,6-dimethylcyclohexadienyl)ruthenium (1), bis(η5-2,6,6-trimethylcyclohexadienyl) ruthenium (2), bis(η5-3,6,6-trimethylcyclohexadienyl)ruthenium (3), bis(η5-2,4,6,6-tetramethylcyclohexadienyl)ruthenium (4) are prepared by reactions between di-μ-chlorodichlorobis[(1-3η:6-8η)-2,7-dimethyloctadienyl] diruthenium and the corresponding dienes. Compound 4 can also be prepared in lower yield by reduction of RuCl3 · nH2O with zinc in the presence of 2,4,6,6-tetramethylcyclohexadiene. Variable temperature 1H NMR studies of 1-4 reveal rapid rotation about the Ru-C bonds. The barrier to rotation in 4 is 7.7 kcal/mol with a gauche-eclipsed ground state conformation. Even lower barriers to rotation in 1-3 contribute to the inability to accurately measure their activation energies in toluene. 相似文献
118.
Birger?PuppeEmail author Peter-Christian?Sch?n Armin?Tuchscherer Gerhard?Manteuffel 《Acta ethologica》2003,5(2):123-129
The nursing vocalisation of lactating sows is an important part of the complex nursing and suckling behaviour of domestic
pigs (Sus scrofa). It helps to lead the young through the several phases of a nursing episode. A total of 135 suckling piglets were investigated
regarding their reactions to different vocalisations and sounds successively replayed in combined choice/open-field experiments.
Two piglet samples were used to determine the impact of age (sample 1: weeks 1 and 5, n=93) and previous test experience of naive older piglets (sample 2: week 5, n=42) on their behavioural responses. In the 1st week after birth, the nursing vocalisation of sows released an initial generalised
approach and contact response in the young, indicating high motivation to gain nutritional or social support. Close to the
sound source, the piglets then strongly preferred the nursing vocalisation produced by their own mothers compared to that
produced by another, unrelated and unfamiliar sow, or an artificial sound composed of similar frequencies as the nurse grunting,
or a control without sound. However, at the end of the suckling period (5-week-old piglets) no clear differences in the reactions
to the sounds could be identified. Moreover, the lack of a clear response at week 5 seems largely independent of any earlier
test experience of the piglets. As well in the 1st as in the 5th week the piglets showed a decrease in open-field activity
when sow grunting was present, indicating that the replay of the nursing vocalisation might have some calming effect.
Communicated by K. Kotrschal 相似文献
119.
Vitrification of immature and in vitro matured pig oocytes: study of distribution of chromosomes, microtubules, and actin microfilaments 总被引:15,自引:0,他引:15
Studies were conducted to compare viability of immature and mature porcine oocytes vitrified in ethylene glycol (EG) using open-pulled straws (OPS). Oocytes that had been allowed to mature for 12 h (germinal vesicle group; GV) and 40 h (metaphase II group; MII) were divided into three treatments: (1) control; (2) treated with cytochalasin B and exposed to EG; and (3) treated with cytochalasin B and vitrified by stepwise exposure to EG in OPS. After warming, a sample of oocytes was fixed and evaluated by specific fluorescent probes before visualization using confocal microscopy. The remaining oocytes were fertilized and cleavage rate was recorded. Exposure of GV oocytes to EG or vitrification had a dramatic effect on spindle and chromosome configurations and no cleavage was obtained after in vitro fertilization. When MII oocytes were exposed to EG or were vitrified, 18 and 11% of oocytes, respectively, maintained the spindle structure and either EG exposure or vitrification resulted in substantial disruption in microfilament organization. The cleavage rates of mature oocytes after being exposed to EG or after vitrification were similar (14 and 13%, respectively) but were significantly less than that of control oocytes (69%). These results indicate that porcine oocytes at different meiotic stages respond differently to cryopreservation and MII porcine oocytes had better resistance to cryopreservation than GV stage oocytes. 相似文献
120.
Kernel smoothing methods are applied to extend a modification of the closed population approach of Lloyd and Yip (1991, in Estimating Equations, 65-88) to open populations with frequent capture occasions. The method complements previous nonparametric methods and, when the parametric assumptions are met, simulations show the new method has a smaller integrated mean squared error than the previous fully nonparametric method. The method is applied to capture-recapture data on short-tailed shearwaters collected annually for 48 years. 相似文献