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141.
A 24 hour start-to-finish method is described for the preparation of three-micron-thick sections of decalcified hard tissues. Following acetone dehydration, the tissue to be embedded is infiltrated under vacuum with a series of graded clearing solutions which approach the content of the final methyl methacrylate mixture. After overnight in a 35 C oven, the plastic is polymerized by four hours heating at 42 C. Three-micron-thick sections are then easily prepared by using a Jung microtome for high resolution histologic or detailed autoradiographic procedures.  相似文献   
142.
R. C. Jee  S. K. De 《Plant and Soil》1968,29(2):335-337
Summary Phosphate fixation by kaolinite, muscovite, phlogopite, biotite and vermiculite from aqueous systems in presence of different quantities of ammonium sulphate, ammonium nitrate and ammonium chloride, have been studied. It is observed that the ammonium salts induce graeter phosphate fixation in presence of kaolinite and partly in presence of phlogopite, biotite and vermiculite.  相似文献   
143.

Purpose

To evaluate the prognostic impact of the lymph node ratio (LNR) in ypStage III rectal cancer patients who were treated with neoadjuvant chemoradiotherapy (NCRT).

Materials and Methods

We retrospectively reviewed the data of 638 consecutive patients who underwent NCRT followed by total mesorectal excision, and postoperative adjuvant chemotherapy for rectal cancer from 2004 to 2011. Of these, 125 patients were positive for lymph node (LN) metastasis and were analyzed in this study.

Results

The median numbers of examined and metastatic LNs were 17 and 2, respectively, and the median LNR was 0.143 (range, 0.02–1). Median follow-up time was 55 months. In multivariate analyses, LNR was an independent prognostic factor for overall survival (OS) (hazard ratio [HR] 2.17, p = 0.041), disease-free survival (DFS) (HR 2.28, p = 0.005), and distant metastasis-free survival (DMFS) (HR 2.30, p = 0.010). When ypN1 patients were divided into low (low LNR ypN1 group) and high LNR (high LNR ypN1 group) according to a cut-off value of 0.152, the high LNR ypN1 group had poorer OS (p = 0.043) and DFS (p = 0.056) compared with the low LNR ypN1 group. And there were no differences between the high LNR ypN1 group and the ypN2 group in terms of the OS (p = 0.703) and DFS (p = 0.831).

Conclusions

For ypN-positive rectal cancer patients, the LNR was a more effective prognostic marker than the ypN stage, circumferential resection margin, or tumor regression grade after NCRT, and could be used to discern the high-risk group among ypN1 patients.  相似文献   
144.
Calcineurin is a Ca2+/Calmodulin activated Ser/Thr phosphatase that is well conserved from yeast to human. In Caenorhabditis elegans, tax-6 and cnb-1 encode catalytic and regulatory subunits of calcineurin, respectively. We performed yeast two-hybrid screening using TAX-6 as a bait to identify calcineurin interacting proteins. KIN-29 is one of proteins that specifically interacted with TAX-6. KIN-29 is a Ser/Thr kinase previously shown to be involved in regulating gene expression of a subset of chemoreceptors in specific neurons. Both TAX-6 and KIN-29 are expressed in hypodermis, muscles, and neurons. Moreover, both calcineurin and kin-29 mutants exhibit similar phenotypes, namely small body size, small brood size, and slow growth. Here we describe specific genetic interaction between tax-6 and kin-29 in regulating body size, serotonin mediated egg laying, and chemoreceptor expression.  相似文献   
145.
Chae  Jae Jin  Park  Young Bae  Kim  Sung Han  Hong  Sung Soo  Song  Gyun Jee  Han  K. H.  Namkoong  Yong  Kim  Hyo Soo  Lee  C. C. 《Human genetics》1997,99(2):155-163
Twenty-eight unrelated persons heterozygous for familial hypercholesterolemia (FH) were screened to assess the frequency and nature of major structural rearrangements at the low-density lipoprotein (LDL) receptor gene in Korean FH patients. Genomic DNA was analyzed by Southern blot hybridization with probes encompassing exons 1–18 of the LDL receptor gene. Two different deletion mutations (FH29 and FH110) were detected in three FH patients (10.7%). Each of the mutations was characterized by the use of exon-specific probes and detailed restriction mapping mediated by long-PCR (polymerase chain reaction). Mutation FH29 was a 3.83-kb deletion extending from intron 6 to intron 8 and FH110 was a 5.71-kb deletion extending from intron 8 to intron 12. In FH29, the translational reading frame was preserved and the deducible result was a cysteine-rich A and B repeat truncated protein that might be unable to bind LDL but would continue to bind β-VLDL. FH110 is presumed to be a null allele, since the deletion shifts the reading frame and results in a truncated protein that terminates in exon 13. Sequence analysis revealed that both deletions have occurred between two Alu-repetitive sequences that are in the same orientation. This suggested that in these patients the deletions were caused by an unequal crossing over event following mispairing of two Alu sequences on different chromatids during meiosis. Moreover, in both deletions, the recombinations were related to an Alu sequence in intron 8 and the deletion breakpoints are found within a specific sequence, 27 bp in length. This supports the hypothesis that this region might have some intrinsic instability, and act as one of the important factors in large recombinational rearrangements. Received: 3 April 1996 / Revised: 19 August 1996  相似文献   
146.
The complete mitochondrial genome (mitogenome) of Saturnia jonasii (Lepidoptera: Saturniidae) was sequenced and compared to those of 19 other bombycoid species. Furthermore, the mitogenome sequences were used to infer phylogenetic relationships among bombycoid species. The 15,261-bp Saturnia jonasii mitogenome contained the typical sets of genes and gene arrangements found in majority of Lepidoptera. All Bombycoidea species, including Saturnia jonasii, have a 15–33-bp spacer sequence at the trnS2-ND1 junction. The phylogenetic reconstruction of bombycoid species consistently and strongly supported monophylies of the families, Saturniidae, Bombycidae, and Sphingidae, based on Bayesian inference (BI) and maximum-likelihood (ML) methods. Among these families, the Bombycidae and Sphingidae species consistently showed a sister relationship, regardless of data partitions; the BI method strongly supported this relationship, whereas it was moderately supported using the ML method.  相似文献   
147.
148.
To investigate the function of dimerization of the TRH receptor, a controlled dimerization system was developed. A variant FK506 binding protein (FKBP) domain was fused to the receptor C terminus and dimerization induced by incubating cells with dimeric FKBP ligand, AP20187. The TRH receptor-fusion bound hormone and signaled normally. Addition of dimerizer to cells expressing the receptor-FKBP fusion dramatically increased the fraction of receptor running as dimer on SDS-PAGE. AP20187 caused dimerization in a time- and concentration-dependent manner, acting within 1 min. Dimerizer had no effect on TRH receptors lacking the FKBP domain, and its effects were blocked by excess monomeric FKBP ligand. AP20187-induced dimerization did not cause receptor phosphorylation, inositol phosphate production, or ERK1/2 activation, and dimerizer did not alter signaling by TRH. Induced dimerization did, however, alter TRH receptor trafficking. TRH promoted greater receptor internalization in cells treated with AP20187 but not monomeric ligand, based on loss of surface binding sites and immunostaining. Dimerization increased the rate of internalization of TRH receptors and decreased the apparent rate of receptor recycling. AP20187 enhanced the small amount of TRH-induced receptor internalization when the receptor-FKBP fusion protein was expressed in cells lacking beta-arrestins. The results show that controlled dimerization of the TRH receptor potentiates hormone-induced receptor trafficking.  相似文献   
149.
IntroductionThe purpose of this research is to evaluate the prospects for the use of 4-(trans-18F-fluoranylmethyl)-N-[2-[4-(2-methoxyphenyl)piperazin-1-yl]ethyl]-N-pyridin-2-ylcyclohexane-1-carboxamide (18F-Mefway) in comparison to 18F-trans-4-fluoro-N-2-[4-(2-methoxyphenyl)piperazin-1-yl]ethyl]-N-(2-pyridyl)cyclohexanecarboxamide (18F-FCWAY) for the quantification of 5-HT1A receptors in human subjects.MethodFive healthy male controls were included for two positron emission tomography (PET) studies: 18F-FCWAY PET after the pretreatment with 500 mg of disulfiram and two months later, 18F-Mefway PET without disulfiram. Regional time-activity curves (TACs) were extracted from nine cortical and subcortical regions in dynamic PET images. Using cerebellar cortex without vermis as reference tissue, in vivo kinetics for both radioligands were compared based on the distribution volume ratio (DVR) calculated by non-invasive Logan graphical analysis and area under the curve ratio of the TACs (AUC ratio).ResultAlthough the pattern of regional uptakes in the 18F-Mefway PET was similar to that of the 18F-FCWAY PET (highest in the hippocampus and lowest in the cerebellar cortex), the amount of regional uptake in 18F-Mefway PET was almost half of that in 18F-FCWAY PET. The skull uptake in 18F-Mefway PET was only 25% of that in 18F-FCWAY PET with disulfiram pretreatment. The regional DVR values and AUC ratio values for 18F-Mefway were 17—40% lower than those of 18F-FCWAY. In contrast to a small overestimation of DVR values by AUC ratio values (< 10%) in 18F-FCWAY PET, the overestimation bias of AUC ratio values was much higher (up to 21%) in 18F-Mefway PET.ConclusionAs 18F-Mefway showed lower DVR values and greater overestimation bias of AUC ratio values, 18F-Mefway may appear less favorable than 18F-FCWAY. However, in contrast to 18F-FCWAY, the resistance to in vivo defluorination of 18F-Mefway obviates the need for the use of a defluorination inhibitor. Thus, 18F-Mefway may be a good candidate PET radioligand for 5-HT1A receptor imaging in human.  相似文献   
150.
One obstacle faced in the effective control of visceral leishmaniasis (VL) is the limited number of available treatment options. Furthermore, control efforts have been hindered further by the emergence of Leishmania resistance to many of the available drugs. In this study, we investigated the anti-leishmanial properties of 30 medicinally important plants from the VL endemic area of Bihar, India and compared them to two available anti-leishmanial drugs (sodium antimony gluconate and amphotericin B) and two plant lectins (phytohemagglutinin and concanavalin A) on Leishmania donovani promastigotes in vitro at 24 and 48 h after initiation of culture. We identified eight plant extracts in addition to phytohemagglutinin and amphotericin B that significantly inhibited the growth of promastigotes (p < 0.03). We further studied the minimum effective concentrations as well as the effect on axenic amastigotes viability and the cell cytotoxicity on human peripheral blood of four (Agave americana, Azadirachta indica, Eclipta alba and Piper longum) of the eight plant extracts that induced significant promastigotes killing (p = 0.00098). Effect-based dose finding analysis revealed that the threshold concentration of A. americana required to eliminate L. donovani after 24 h was 0.05 mg/ml. A. indica and P. longum plant extracts eliminated L. donovani promastigotes after 48 h at concentrations of 0.1 and 0.5 mg/ml, respectively. E. alba eliminated the promastigotes at a concentration of 0.5 mg/ml within 24 h. The axenic amastigote killing response was 1.90-, 2.52- and 1.3-fold higher than the promastigote killing response with A. indica, A. americana and E. alba plant extracts, respectively. A. americana and A. indica, respectively, led to approximate 2.5- and 1.3-fold declines in mitochondrial dehydrogenase activity compared with control. E. alba stimulation resulted in an up-regulation of dehydrogenase activity (p = 0.00329). The CSA from P. longum was found to be least cytotoxic; the observed difference in mitochondrial activity was insignificant (p = 0.16314). Further studies may reveal the pharmacological significance of many of the plants with anti-leishmanial properties identified in the present study.  相似文献   
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