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991.
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1. 1.|The brain (BR), suboesophageal ganglion (SOG), metathoracic ganglion mass (TG3) or fourth free abdominal ganglion (AG4) were selectively warmed from room temperature (23°C) to 3°C and the effects of elevated ganglion temperature on abdominal ventilatory pumping rate were observed.

2. 2.|Warming the SOG or BR almost always induced a strong increase in ventilatory pumping rate while warming TG3 or AG4 had no consistent effect, inducing about equally often a slight increase, decrease or no change.

3. 3.|It is concluded that the most temperature sensitive elements associated with the ventilatory rhythm generating system are localized within the head ganglia.

Author Keywords: Insect; Gryllus bimaculatus; abdominal ventilation; CNS thermosensitivity  相似文献   

995.
Carp muscle calcium binding parvalbumin, crystallized in 2.9 m-ammonium sulfate, can bind two Tb3+ ions, which displace the two Ca2+ ions normally present. The Ca2+ co-ordinated in the loop between the E and the F α-helices is displaced at low Tb3+ concentrations; whereas the Ca2+ at the CD site is replaced only at higher Tb3+ concentration. There is not a third Tb3+ site as had been suggested in interpretations of Tb3+ fluorescence experiments performed without ammonium sulfate. A third electron density peak in the difference Fourier maps is tentatively assigned to a sulfate ion co-ordinating the EF site Tb3+ ion.  相似文献   
996.
PRP-hexapeptide possessing the azo-bridge between Tyr1 and Phe5 residues, called azo-PRP-hexapeptide: (formula; see text), was synthesized and tested for immunoregulatory activity. High biological activity of the synthesized azo-PRP-hexapeptide suggests that the biologically active conformation of PRP-hexapeptide must be such that both aromatic rings (Tyr and Phe) are apparently close to each other.  相似文献   
997.
DNA double-strand breaks (DSBs) are a serious threat to the cell, for if not or miss-repaired, they can lead to chromosomal aberration, mutation and cancer. DSBs in human cells are repaired via non-homologous DNA end joining (NHEJ) and homologous recombination repair pathways. In the former process, the structure of DNA termini plays an important role, as does the genetic constitution of the cells, through being different in normal and pathological cells. In order to investigate the dependence of NHEJ on DSB structure in normal and cancer cells, we used linearized plasmids with various, complementary or non-complementary, single-stranded or blunt DNA termini, as well as whole-cell extract isolated from normal human lymphocytes, chronic myeloid leukemia K562 cells and lung cancer A549 cells. We observed a pronounced variability in the efficacy of NHEJ reaction depending on the type of ends. Plasmids with complementary and blunt termini were more efficiently repaired than the substrate with 3' protruding single-strand ends. The hierarchy of the effectiveness of NHEJ was on average, from the most effective to the least, A549/ normal lymphocytes/ K562. Our results suggest that the genetic constitution of the cells together with the substrate terminal structure may contribute to the efficacy of the NHEJ reaction. This should be taken into account on considering its applicability in cancer chemo- or radiotherapy by pharmacologically modulating NHEJ cellular responses.  相似文献   
998.

Background

Clinical progression of colorectal cancers (CRC) may occur in parallel with distinctive signaling alterations. We designed multidirectional analyses integrating microarray-based data with biostatistics and bioinformatics to elucidate the signaling and metabolic alterations underlying CRC development in the adenoma-carcinoma sequence.

Methodology/Principal Findings

Studies were performed on normal mucosa, adenoma, and carcinoma samples obtained during surgery or colonoscopy. Collections of cryostat sections prepared from the tissue samples were evaluated by a pathologist to control the relative cell type content. The measurements were done using Affymetrix GeneChip HG-U133plus2, and probe set data was generated using two normalization algorithms: MAS5.0 and GCRMA with least-variant set (LVS). The data was evaluated using pair-wise comparisons and data decomposition into singular value decomposition (SVD) modes. The method selected for the functional analysis used the Kolmogorov-Smirnov test. Expressional profiles obtained in 105 samples of whole tissue sections were used to establish oncogenic signaling alterations in progression of CRC, while those representing 40 microdissected specimens were used to select differences in KEGG pathways between epithelium and mucosa. Based on a consensus of the results obtained by two normalization algorithms, and two probe set sorting criteria, we identified 14 and 17 KEGG signaling and metabolic pathways that are significantly altered between normal and tumor samples and between benign and malignant tumors, respectively. Several of them were also selected from the raw microarray data of 2 recently published studies (GSE4183 and GSE8671).

Conclusion/Significance

Although the proposed strategy is computationally complex and labor–intensive, it may reduce the number of false results.  相似文献   
999.
BACKGROUND: Amniotic rupture sequence (ARS) is a disruption sequence presenting with fibrous bands, possibly emerging as a result of amniotic tear in the first trimester of gestation. Our comparative study aims to assess whether there is a difference in the clinical pattern of congenital limb and internal organ anomalies between ARS with body wall defect (ARS‐BWD) and ARS without BWD (ARS‐L). METHODS: Among 1,706,639 births recorded between 1998 and 2006, 50 infants with a diagnosis of ARS were reported to the Polish Registry of Congenital Malformations. The information on 3 infants was incomplete, thus only 47 cases were analyzed. These infants were classified into groups of ARS‐L (38 infants) and ARS‐BWD (9 infants). RESULTS: The ARS‐BWD cases were more frequently affected by various congenital defects (overall p < 0.0001), and in particular by urogenital malformations (p = 0.003). In both groups, limb reduction defects occurred in approximately 80% of cases; however, minor and distal limb defects (phalangeal or digital amputation, pseudosyndactyly, constriction rings) predominated in the ARS‐L group (p = 0.0008). The ARS‐L group also had a higher frequency of hand and upper limb involvement. CONCLUSIONS: This observation suggests that amniotic band adhesion in ARS‐L takes place at a later development stage. Although limited by a small sample size, our study contributes to the growing evidence that both ARS entities represent two nosologically distinct conditions. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
1000.
The purpose of this study was to compare hybrid capture assay with PCRs using different primers for the L1, E6-E7 regions for the detection of human papillomavirus (HPV) genome. One hundred twenty-five cervical smears with normal (n=42) and abnormal (n=83) cytology were investigated. Those at high-risk for HPV were studied by hybridization antibody capture assay and PCR with the pU-1M/pU-2R primers. Target DNA from the HPV L1 region was amplified by SPF10 primer set and home-PCR with MY09/MY11 primers. The presence of HPV DNA in cervical smears was detected by SPF10 (in 72% of cases), MY09/MY11 (58%), hybrid capture (55%) and pU-1M/pU-2R (39%). Results obtained with the SPF10 and MY09/MY11 consensus primer sets as well as hybrid capture and pU-1M/pU-2R specific for high-risk types differed significantly (chi2, P<0.0005). The correlation between assays with the use of SPF10 and MY09/MY11 was 86% and between hybrid capture and the pU-1M/pU2R technique--78%. In 49% of samples HPV DNA was detected by the four methods, whereas in 12% only by the SPF10 primers. The most sensitive technique was found to be PCR with the use of SPF10 primers, while the most specific--the MY09/11 PCR method. It seems that home-PCR with MY09/MY11 primers could be applied in screening tests.  相似文献   
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