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41.
42.
Mary Ellen Morbeck Alison Galloway Adrienne L. Zihlman Kenneth M. Mowbray 《Primates; journal of primatology》1994,35(1):99-103
Skeletons of chimpanzees with recorded life stories allow assessment of the potential relationships among hard tissue features
and expressed behaviors. We analyze bone size, weight, and mineralization to assess osteological characters for identification
of laterality of expressed behaviors involving the upper body. Results show that associations are not yet clearly defined. 相似文献
43.
44.
The Bcl-2 family of proteins: regulators of cell death and survival 总被引:15,自引:0,他引:15
The Bcl-2 protein inhibits apoptosis induced by a variety of signals, in a range of cell types and in diverse organisms, and it is implicated in both normal development and oncogenesis. Despite this central role, the mechanism of action of Bcl-2 is not yet clear. Recent studies have uncovered a number of Bcl-2-related gene products that regulate apoptosis either negatively or positively, and Bcl-2 forms heterodimers with at least one of these proteins, Bax. This article discusses the role of the Bcl-2 family of proteins in the light of these findings. 相似文献
45.
Michael D. Browning Shuichi Endo Geoffrey B. Smith Ellen M. Dudek Richard W. Olsen 《Neurochemical research》1993,18(1):95-100
Previous work has shown that the GABAA-receptor (GABAA-R) could be phosphorylated by cAMP-dependent protein kinase (PKA), protein kinase C (PKC), and a receptor associated kinase. However, no clear picture has yet emerged concerning the particular subunit subtypes of the GABAA-R that were phosphorylated by PKA and PKC. In the present report we show that an antibody raised against a 23 amino acid polypeptide corresponding to a sequence in the putative intracellular loop of the 1 subunit of the receptor blocks the in vitro phosphorylation of the purified receptor by PKA and PKC. Moreover, N-terminal sequence analysis of the principal phosphopeptide fragment obtained after proteolysis of the receptor yielded a sequence that corresponds to the 3 subunit of the receptor. Such data provide additional support for our hypothesis (Browning et al., 1990, Proc. Natl. Acad. Sci. USA 87:1315–1317) that both PKA and PKC phosphorylate the -subunit of the GABAA-R.Special issue dedicated to Dr. Paul Greengard. 相似文献
46.
Book reviewed in this article:
White Justice . 1987. Directed by Morgane Laliberte and Françoise Wera .
Inughuit: The People at the Navel of the Earth . 1987. A film by Staffan Julen and Ylva Julen .
Uksuum Cauyaii : The Drums of Winter . 1988. A film by Sarah Elder and Leonard Kammerling .
In Irigu's Time . 1987. A film by Katrina Waters . 相似文献
White Justice . 1987. Directed by Morgane Laliberte and Françoise Wera .
Inughuit: The People at the Navel of the Earth . 1987. A film by Staffan Julen and Ylva Julen .
Uksuum Cauyaii : The Drums of Winter . 1988. A film by Sarah Elder and Leonard Kammerling .
In Irigu's Time . 1987. A film by Katrina Waters . 相似文献
47.
OBJECTIVE: To describe survival, disability, and morbidity after radiotherapy for malignant glioma. DESIGN: Two year prospective study with home interviews with patients and relatives. SETTING: Seven neurosurgical and radiotherapy centres in London. SUBJECTS: 105 patients aged 21 to 75: 59 had biopsy; 46 had partial macroscopic resection; 92 received radiotherapy; and 13 received steroids alone. MAIN OUTCOME MEASURES: Survival, time free from disability, and changes in disability after treatment. RESULTS: Six and 12 month survival for radiotherapy patients was 70% and 39%, respectively. Age, World Health Organisation clinical performance status, extent of surgery, and history of seizures before diagnosis each influenced survival. The Medical Research Council prognostic index was also significantly related to survival. Multivariate analysis showed that initial clinical performance status was the most important component of the index. Most (80%; 49/61) patients with a clinical performance status of 0, 1, or 2 lived at least six months before becoming permanently disabled. Most patients who had initially had a good clinical performance status (0-2) and who were alive six months after radiotherapy (68%; 36/52), however, had experienced either clinical deterioration or severe tiredness after treatment. In 17% (9/52) of these some permanent loss of function remained. These adverse effects were associated with increasing radiotherapy dose. Severely disabled patients (clinical performance status 3 or 4) gained little benefit. CONCLUSION: Severely disabled patients gain little physical benefit from radiotherapy, whereas those not so disabled may experience considerable adverse effects. 相似文献
48.
Kay Denyer Belinda Clarke Christopher Hylton Helma Tatge Alison M. Smith 《The Plant journal : for cell and molecular biology》1996,10(6):1135-1143
The aim of this work was to investigate the conditions required for amylose synthesis in starch granules. Although the major granule-bound isoform of starch synthase - GBSSI - catalyses the synthesis of amylose in vivo, 14C from ADP[14C]glucose was incorporated primarily into a specific subset of amylopectin chains when supplied to starch granules isolated from pea (Pisum sativum L.) embryos and potato (Solanum tuberosum L.) tubers. Incubation of granules with soluble extracts of these organs revealed that the extracts contained compounds that increased the incorporation of 14C into amylose. These compounds were rendered inactive by treatment of the extracts with α-glucosidase, suggesting that they were malto-oligosaccharides. Consistent with this idea, provision of pure malto-oligosaccharides to isolated granules resulted in a dramatic shift in the pattern of incorporation of 14C, from amylopectin chains to amylose molecules. Comparison of the pattern of incorporation in granules from wild-type peas and lam mutant peas which lack GBSSI showed that this effect of malto-oligosaccharides was specifically on GBSSI. The significance of these results for understanding of the synthesis of amylose and amylopectin in storage organs is discussed. 相似文献
49.
The voltage sensitivity of the fluorescent styrylpyridinium dye RH421 has been investigated in dimyristoylphosphatidylcholine vesicles by inducing an intramembrane electric field through the binding of the hydrophobic ion tetraphenylborate (TPB). To assess the probability of electrochromic and solvatochromic mechanisms for the dye response, the ground-state dipole moment of the dye in chloroform solution was determined from dielectric constant measurements to be 12 (+/- 1) Debye, and the change in dipole moment upon excitation was calculated from measurements of the Stokes shift in solvents of varying polarity to be 25 (+/- 11) Debye. As well as causing absorbance and fluorescence changes of membrane-bound dye, the TPB-induced electrical field was found to reduce significantly the pKa of the dye. The pH at which experiments are carried out is, thus, an important factor in determining the amplitude of the voltage-induced absorbance and fluorescence changes. The observed absorbance changes induced by the field are inconsistent with a pure electrochromic mechanism. A reorientation/solvatochromic mechanism, whereby the electrical field reorients the dye molecules so that they experience a change in polarity of their lipid environment is likely to make a significant contribution to both the spectral changes and to the field effect on the acid-base properties of the dye. 相似文献
50.