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1.
Book Reviews     
Book reviewed in this article:
The Natural Historv of Antelopes By C. A. Spinage.  

Shorter notices


Towards Hazard Assessment: Properties and Effects of Endosulphan Applied Sequentially as Drift Spray for Tsetse Fly Control by R. J. Douthwaite.
WWF Yearbook 1985/86, Ed. by Cassandra Philips.
Evolutionary Biology (Second Edition) by D. J. Futuyma.
Community Ecology: Patterns and Process, Ed. by J. Kikkawa & D. J. Anderson.
Tropical Ecology by D. E. Pomeroy & M. W. Service (with contributions by J. K. E. Egunjobi & N. Dickinson).
Our Common Future: A Reader's Guide by D. Hinrischen.
Kora: An Ecolgical Inventory of'the Kora Nuriontal Reserve, Kenya, Ed. by M. Coe & N. M. Collins
Colonisation, Succession and Stability, Ed. by A. J. Gray, M. J. Crawley & P. J Edwards.
Mediterranean Marine. Avifauna: Population Studies.r and Conservation, Ed. By MEDMARAVIS & X. Monbailliu.  相似文献   

2.

Background

Eating disorders appear to be caused by a complex interaction between environmental and genetic factors, and compulsive eating in response to adverse circumstances characterizes many eating disorders.

Materials and Methods

We compared compulsion-like eating in the form of conditioned suppression of palatable food-seeking in adverse situations in stressed C57BL/6J and DBA/2J mice, two well-characterized inbred strains, to determine the influence of gene-environment interplay on this behavioral phenotype. Moreover, we tested the hypothesis that low accumbal D2 receptor (R) availability is a genetic risk factor of food compulsion-like behavior and that environmental conditions that induce compulsive eating alter D2R expression in the striatum. To this end, we measured D1R and D2R expression in the striatum and D1R, D2R and α1R levels in the medial prefrontal cortex, respectively, by western blot.

Results

Exposure to environmental conditions induces compulsion-like eating behavior, depending on genetic background. This behavioral pattern is linked to decreased availability of accumbal D2R. Moreover, exposure to certain environmental conditions upregulates D2R and downregulates α1R in the striatum and medial prefrontal cortex, respectively, of compulsive animals. These findings confirm the function of gene-environment interplay in the manifestation of compulsive eating and support the hypothesis that low accumbal D2R availability is a “constitutive” genetic risk factor for compulsion-like eating behavior. Finally, D2R upregulation and α1R downregulation in the striatum and medial prefrontal cortex, respectively, are potential neuroadaptive responses that parallel the shift from motivated to compulsive eating.  相似文献   

3.
The phagocytic activity of blood granulocytes can be quantitatively assayed by ingestion of opsonised paraffin oil droplets containing the dye Oil Red-O (Stossel, T. P., Mason, R. J., Hartwig, J., and Vaughan, M. (1972)J. Clin. Invest. 51:615–624). We have modified this assay by incorporating [3H]glycerol into the oil droplets which allows a more sensitive and reproducible measurement of the phagocytic competence of blood granulocytes even at very low cell counts. Comparative studies after one day storage of the blood at 4°C is feasible since they retain 84 % of the phagocytic capacity measured when isolated from fresh blood.  相似文献   

4.
Uptake kinetics of nitrogen derived from sewage–seawater mixtures (2.5–20% v/v effluent) were determined in the laboratory for Ulva rigida (Chlorophyceae) native from Bahía Nueva (Golfo Nuevo, Patagonia, Argentine). In terms of nitrogen concentration, experimental enrichment levels varied between 53.7 and 362.3M of ammonium and between 0.77 and 6.21M of nitrate+nitrite. Uptake rates were fitted to the Michaelis–Menten equation, with the following kinetic parameters: ammonium: Vmax = 591.2molg–1h–1, K s=262.3M, nitrate+nitrite: V max=12.9molg–1h–1, K s=3.5M). Both nutrients were taken up simultaneously, but ammonium incorporation was faster in all cases. The results show a high capability of Ulva rigida to remove sewage-derived nitrogen from culture media. In the field, most of the nitrogen provided by the effluent would be tied up in algal biomass, supporting low nitrogen levels found at a short distance away from the source.  相似文献   

5.

Book Review

Hormone action in plant development: A critical appraisalG.V. Hoad, J.R. Lenton, M.B. Jackson and R.K. Atkin (Eds.), London: Butterworths, 1987. 315 pages. £21.00. ISBN 0408 007966  相似文献   

6.

Book review

Plant analysis — as a guide to the nutrient requirements of temperate and tropical cropsP. Martin-Prevel, J. Gagnard and P. Gautier (Eds.), [translated from the French by M.R.J. Holmes]. New York: Lavoisier Publishing Inc., 1987. xx + 722 pages. US$112. ISBN 2-85206-364-6  相似文献   

7.
Myocardial apoptosis is primarily triggered during reperfusion (R). The aim of this study was to test the hypothesis that R-induced apoptosis develops progressively during the late phase of R, and that R-induced apoptosis is associated with changes in expression of anti- and pro-apoptotic proteins and infiltrated inflammatory cells. Thirty-one dogs were subjected to 60 min of left anterior descending coronary occlusion followed by 6, 24, 48, and 72 h R, respectively. There was no group difference in collateral blood flow, measured by colored microspheres during ischemia. Necrotic cell death (TTC staining) was significantly increased during R, starting at 27 ± 2% at 6 h R and increasing to 41 ± 2% at 24 h R. There was no further change at 48 (37 ± 3%) and 72 (36 ± 6%) h R, respectively. TUNEL positive cells (% total normal nuclei) in the peri-necrotic zone progressively increased from 6 (26 ± 2*) to 24 (38 ± 1*), 48 (48 ± 3*) and 72 (59 ± 4*) h R, respectively. The number of detected TUNEL positive cells at these time points was consistent with an increased intensity of DNA ladders, identified by agarose gel electrophoresis. Compared with normal tissue, western blot analysis showed persistent reduction in expression of anti-apoptotic protein Bcl-2 from 6 (16 ± 0.8%*) to 72 h R (78 ± 2%*), and increase in expression of pro-apoptotic proteins including Bax from 6 (30 ± 3%*) to 72 h R (66 ± 3%*), and p53 from 6 (12 ± 1%*) to 72 h R (91 ± 2%*), respectively. Immunohistochemical staining revealed that infiltrated neutrophils (mm2 myocardium) were significantly correlated with development of necrotic and apoptotic cell death from 6 to 24 h R, respectively (P < 0.05), while large macrophage infiltration seen during 48 to 72 h R were correlated with apoptotic cell death (P < 0.05). These results indicate that 1) necrosis peaked at 24 h R when apoptosis was still progressively developing during later R; 2) changes in Bcl-2 family and p53 proteins may participate in R-induced myocardial apoptosis; 3) inflammatory cells may play a role in triggering cell death during R. * P < 0.05 vs. normal nuclei and tissue; P < 0.01 vs. 6 h R.  相似文献   

8.

Book reviews

Improving vegetatively propagated cropsA.J. Abbott and R.K. Atkin (Eds.), London: Academic Press, 1987. xvii + 416 pages. £37.00. 0-12-041410-4  相似文献   

9.
Walter Gams 《Mycopathologia》2004,158(3):395-396

Book Review

Book Review:R.J. Cole, B.B. Jarvis and M.A. Schweikert eds.Handbook of Secondary Fungal metabolites, AcademicPress, UK, 2003. 2544 pp. $299.95.  相似文献   

10.

Aim

To investigate the influence of metformin use on liver dysfunction and hepatic encephalopathy in a retrospective cohort of diabetic cirrhotic patients. To analyze the impact of metformin on glutaminase activity and ammonia production in vitro.

Methods

Eighty-two cirrhotic patients with type 2 diabetes were included. Forty-one patients were classified as insulin sensitizers experienced (metformin) and 41 as controls (cirrhotic patients with type 2 diabetes mellitus without metformin treatment). Baseline analysis included: insulin, glucose, glucagon, leptin, adiponectin, TNFr2, AST, ALT. HOMA-IR was calculated. Baseline HE risk was calculated according to minimal hepatic encephalopathy, oral glutamine challenge and mutations in glutaminase gene. We performed an experimental study in vitro including an enzymatic activity assay where glutaminase inhibition was measured according to different metformin concentrations. In Caco2 cells, glutaminase activity inhibition was evaluated by ammonia production at 24, 48 and 72 hours after metformina treatment.

Results

Hepatic encephalopathy was diagnosed during follow-up in 23.2% (19/82): 4.9% (2/41) in patients receiving metformin and 41.5% (17/41) in patients without metformin treatment (logRank 9.81; p = 0.002). In multivariate analysis, metformin use [H.R.11.4 (95% CI: 1.2–108.8); p = 0.034], age at diagnosis [H.R.1.12 (95% CI: 1.04–1.2); p = 0.002], female sex [H.R.10.4 (95% CI: 1.5–71.6); p = 0.017] and HE risk [H.R.21.3 (95% CI: 2.8–163.4); p = 0.003] were found independently associated with hepatic encephalopathy. In the enzymatic assay, glutaminase activity inhibition reached 68% with metformin 100 mM. In Caco2 cells, metformin (20 mM) decreased glutaminase activity up to 24% at 72 hours post-treatment (p<0.05).

Conclusions

Metformin was found independently related to overt hepatic encephalopathy in patients with type 2 diabetes mellitus and high risk of hepatic encephalopathy. Metformin inhibits glutaminase activity in vitro. Therefore, metformin use seems to be protective against hepatic encephalopathy in diabetic cirrhotic patients.  相似文献   

11.

Introduction

Low-to-moderate intensity exercise improves muscle contractile properties and endurance capacity in multiple sclerosis (MS). The impact of high intensity exercise remains unknown.

Methods

Thirty-four MS patients were randomized into a sedentary control group (SED, n = 11) and 2 exercise groups that performed 12 weeks of a high intensity interval (HITR, n = 12) or high intensity continuous cardiovascular training (HCTR, n = 11), both in combination with resistance training. M.vastus lateralis fiber cross sectional area (CSA) and proportion, knee-flexor/extensor strength, body composition, maximal endurance capacity and self-reported physical activity levels were assessed before and after 12 weeks.

Results

Compared to SED, 12 weeks of high intensity exercise increased mean fiber CSA (HITR: +21±7%, HCTR: +23±5%). Furthermore, fiber type I CSA increased in HCTR (+29±6%), whereas type II (+23±7%) and IIa (+23±6%,) CSA increased in HITR. Muscle strength improved in HITR and HCTR (between +13±7% and +45±20%) and body fat percentage tended to decrease (HITR: -3.9±2.0% and HCTR: -2.5±1.2%). Furthermore, endurance capacity (Wmax +21±4%, time to exhaustion +24±5%, VO2max +17±5%) and lean tissue mass (+1.4±0.5%) only increased in HITR. Finally self-reported physical activity levels increased 73±19% and 86±27% in HCTR and HITR, respectively.

Conclusion

High intensity cardiovascular exercise combined with resistance training was safe, well tolerated and improved muscle contractile characteristics and endurance capacity in MS.

Trial Registration

ClinicalTrials.gov NCT01845896  相似文献   

12.

Background

Gastric cancer (GC) is the fifth most common malignancy and remains a considerable public health burden worldwide. Genetic variations in genes encoding cytokines and their receptors influence the intensity of the Helicobacter pylori associated inflammatory response, which may contribute to individual differences in the outcome and severity of the disease. Interleukin4 is a typical pleiotropic T helper 2 (Th2) cytokine and is a critical mediator of Th1/Th2 balance. It is involved in the regulation of inflammation-mediated carcinogenesis in human organs, including gastric cancer.

Objective

The present retrospective case control study was undertaken to evaluate the association of IL4 intron 3 VNTR polymorphism with the susceptibility to GC in a south Indian population from Telangana state.

Materials and Methods

A total of 182 patients with diagnosed GC and 326 randomly selected healthy controls were enrolled in the present study. Genomic DNA was extracted from peripheral leukocytes and genotyping was determined by PCR-based assay. Association between genotypes and gastric cancer was examined by unconditional logistic regression analysis.

Result

The variant 3R/2R and 2R/2R genotypes of IL4 exon3 VNTR polymorphism had about 1.9 fold and 3fold increased GC risk, respectively, when compared with 3R/3R genotype [3R/2R vs. 3R/3R: adjusted odds ratio (AOR) = 1.90, 95% confidence interval (CI) = 1.23–2.95 P = 0.004 and 2R/2R vs. 3R/3R: AOR (95%CI) = 2.96 (1.29–6.82), P = 0.011]. Furthermore, a significant increased risk of GC was found for the 2R allele carriers (3R/2R + 2R/2R) compared with the 3R/3R genotype (AOR (95%CI) = 2.04 (1.35–3.10), P = <0.000). The IL4 2R allele frequency was 0.28 among the GC group and 0.18 among the controls, and the difference was statistically significant (P = <0.000).

Conclusion

The present study revealed an association of 2R allele and 2R carrier genotypes in the etiopathogenesis of GC in south Indian population.  相似文献   

13.

Background

Activation of ATP-gated P2X7 receptors (P2X7R) in macrophages leads to production of reactive oxygen species (ROS) by a mechanism that is partially characterized. Here we used J774 cells to identify the signaling cascade that couples ROS production to receptor stimulation.

Methods

J774 cells and mP2X7-transfected HEK293 cells were stimulated with Bz-ATP in the presence and absence of extracellular calcium. Protein inhibitors were used to evaluate the physiological role of various kinases in ROS production. In addition, phospho-antibodies against ERK1/2 and Pyk2 were used to determine activation of these two kinases.

Results

ROS generation in either J774 or HEK293 cells (expressing P2X7, NOX2, Rac1, p47phox and p67phox) was strictly dependent on calcium entry via P2X7R. Stimulation of P2X7R activated Pyk2 but not calmodulin. Inhibitors of MEK1/2 and c-Src abolished ERK1/2 activation and ROS production but inhibitors of PI3K and p38 MAPK had no effect on ROS generation. PKC inhibitors abolished ERK1/2 activation but barely reduced the amount of ROS produced by Bz-ATP. In agreement, the amount of ROS produced by PMA was about half of that produced by Bz-ATP.

Conclusions

Purinergic stimulation resulted in calcium entry via P2X7R and subsequent activation of the PKC/c-Src/Pyk2/ERK1/2 pathway to produce ROS. This signaling mechanism did not require PI3K, p38 MAPK or calmodulin.

General significance

ROS is generated in order to kill invading pathogens, thus elucidating the mechanism of ROS production in macrophages and other immune cells allow us to understand how our body copes with microbial infections.  相似文献   

14.

Book Review

Proteasome Inhibitors in Cancer Therapy (J. Adams (ed.), Humana Press, Totowa-New Jersey, 2004, 313 p., $ 155.0)  相似文献   

15.

Correction to: The EMBO Journal (2021) 40: e107786. DOI 10.15252/embj.2021107786 | Published online 8 June 2021The authors would like to add three references to the paper: Starr et al and Zahradník et al also reported that the Q498H or Q498R mutation has enhanced binding affinity to ACE2; and Liu et al reported on the binding of bat coronavirus to ACE2.Starr et al and Zahradník et al have now been cited in the Discussion section, and the following sentence has been corrected from:“According to our data, the SARS‐CoV‐2 RBD with Q498H increases the binding strength to hACE2 by 5‐fold, suggesting the Q498H mutant is more ready to interact with human receptor than the wildtype and highlighting the necessity for more strict control of virus and virus‐infected animals”.to“Here, according to our data and two recently published papers, the SARS‐CoV‐2 RBD with Q498H or Q498R increases the binding strength to hACE2 (Starr et al, 2020; Zahradník et al, 2021), suggesting the mutant with Q498H or Q498R is more ready to interact with human receptor than the wild type and highlighting the necessity for more strict control of virus and virus‐infected animals”.The Liu et al citation has been added to the following sentence:“In another paper published by our group recently, RaTG13 RBD was found to bind to hACE2 with much lower binding affinity than SARS‐CoV‐2 though RaTG13 displays the highest whole‐genome sequence identity (96.2%) with the SARS‐CoV‐2 (Liu et al, 2021)”.Additionally, the authors have added the GISAID accession IDs to the sequence names of the SARS‐CoV‐2 in two human samples (Discussion section). To make identification unambiguous, the sequence names have been updated from “SA‐lsf‐27 and SA‐lsf‐37” to “GISAID accession ID: EPI_ISL_672581 and EPI_ISL_672589”.Lastly, the authors declare in the Materials and Methods section that all experiments employed SARS‐CoV‐2 pseudovirus in cultured cells. These experiments were performed in a BSL‐2‐level laboratory and approved by Science and Technology Conditions Platform Office, Institute of Microbiology, Chinese Academy of Sciences.These changes are herewith incorporated into the paper.  相似文献   

16.
The natural remobilization of an initially static mixed dense non-aqueous phase liquid (DNAPL) pool due to dissolution was demonstrated by (Roy et al. 2002 Roy, J. W., Smith, J. E. and Gillham, R. W. 2002. Natural remobilization of multicomponent DNAPL pools due to dissolution. J. Contam. Hydrol., 59: 163186. [Crossref], [PubMed], [Web of Science ®] [Google Scholar], 2004 Roy, J. W., Smith, J. E. and Gillham, R. W. 2004. Laboratory evidence of natural remobilization of multicomponent DNAPL pools due to dissolution. J. Contam. Hydrol., 74: 145161. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]) using a compositional mathematical model and laboratory experiments with open pools over a porous medium. The purposes of this study were to: a) demonstrate natural remobilization for a pool within porous media (as opposed to an open pool); and b) analyze the capillary effects associated with residual formation, a changing saturation profile, hysteresis, and aging, as these processes may reduce the potential for natural remobilization of pools in porous media. DNAPL pools comprised of tetrachloroethene and benzene were created within a zone of larger glass beads overlying smaller glass beads, in a water-saturated 2-D flow cell. In one case, remobilization occurred in the form of a DNAPL finger, after 56 days of flushing. In another case, no remobilization had occurred after 64 days of flushing, though the density increased by 430 kg m ?3 and remobilization was predicted by the compositional model. Comparison of observations with model predictions suggest that contact angle hysteresis, related to an observed change in wettability, was the most significant contributing factor causing overprediction of the potential for natural remobilization.  相似文献   

17.
《Plant Growth Regulation》1991,10(2):174-175

Book Review

Molecular and genetic aspects of nitrate assimilationJ.L. Wray and J.R. Kinghorn (Eds.), Oxford, New York, Tokyo: Oxford Science Publications, 1989. xv + 410 pages. £45.00. ISBN 0-19-857696-X  相似文献   

18.

Book Review

Photosynthesis: Molecular biology and bioenergeticsG.S. Singhal, J. Barber, R.A. Dilley, Govindjee, R. Haselkorn and P. Mohanty (Eds), Proceedings of the International Workshop on Application of Molecular Biology and Bioenergetics of Photosynthesis. Berlin, Heidelberg, New York, London, Paris, Tokyo, Hong Kong and Narosa: Springer-Verlag, 1989. xiv+441 pages. DM 148,00. ISBN 3-540-50451-6  相似文献   

19.
Summary The structure of the basement membrane of Saccoglossus horsti has been examined with the electron microscope. The membrane consists of two lamellae each of two layers. An outer amorphous layer 150 nm across and an inner fibrillar layer 1–3 m across. The fibrils of the fibrillar layer are two sizes, the majority are 5–9 nm in diameter and at least 2 m long. The thicker 30 nm fibrils occur in small patches and have striations with a 30 nm period.Within the lamellae of the basement membrane are blood spaces. The only regularly found structures in these spaces are blood particles some 12–16 nm in diameter.Nerve fibres of varying diameters traverse all the layers of basement membrane. These fibres run longitudinally and obliquely through the basement membrane, and emerge amongst the muscle cells inserted into the coelomic side of the membrane. No motor end plates have been seen. Preliminary observations suggest that many of the nerve fibres have no sheath other than the cell membrane of the fibre itself.The muscle cells are attached to the basement membrane by structures that resemble hemidesmosomes. The blood vessels of Saccoglossus have a basement membrane on the lumenal side of the endothelial cell cytoplasm.I wish to thank Professor J. Z. Young, F. R. S. for continuous encouragement and advice. To Dr. R. Newell I am indebted for the collection and identification of the specimens. I am pleased to acknowledge my debt to Dr. R. Bellairs for the use of electron microscope facilities, and to Mrs. J. Hamilton and Mr. R. Moss for skillful technical assistance.  相似文献   

20.

Background

Riemerella anatipestifer is one of the most important pathogens of ducks. However, the molecular mechanisms of R. anatipestifer infection are poorly understood. In particular, the lack of genomic information from a variety of R. anatipestifer strains has proved severely limiting.

Results

In this study, we present the complete genomes of two R. anatipestifer strains, RA-CH-1 (2,309,519 bp, Genbank accession CP003787) and RA-CH-2 (2,166,321 bp, Genbank accession CP004020). Both strains are from isolates taken from two different sick ducks in the SiChuang province of China. A comparative genomics approach was used to identify similarities and key differences between RA-CH-1 and RA-CH-2 and the previously sequenced strain RA-GD, a clinical isolate from GuangDong, China, and ATCC11845.

Conclusion

The genomes of RA-CH-2 and RA-GD were extremely similar, while RA-CH-1 was significantly different than ATCC11845. RA-CH-1 is 140,000 bp larger than the three other strains and has 16 unique gene families. Evolutionary analysis shows that RA-CH-1 and RA-CH-2 are closed and in a branch with ATCC11845, while RA-GD is located in another branch. Additionally, the detection of several iron/heme-transport related proteins and motility mechanisms will be useful in elucidating factors important in pathogenicity. This information will allow a better understanding of the phenotype of different R. anatipestifer strains and molecular mechanisms of infection.  相似文献   

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