DISCUSSION OF A NATIONAL OBSERVATORY     

Newcomb S  Hall A  Young CA  Mendenhall TC  Woodward RS  Doolittle CL  Pickering WH  Searle A  Very FW  Todd DP  Myers GW  Fuertes EA  Elkin WL  Keeler JE 《Science (New York, N.Y.)》1899,9(222):467-476

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Temperature in the monkey: transmitter factors released from the brain during thermoregulation   总被引：2，自引：0，他引：2  

R D Myers  L G Sharpe 《Science (New York, N.Y.)》1968,161(841):572-573

When perfusate is collected from the anterior hypothalamus of a cooled donor monkey and is transfused to a corresponding hypothalamic site in a normal monkey, fever occurs in this recipient. Conversely, perfusate from a heated donor monkey lowers the recipient monkey's temperature when the same hypothalamic transfusion procedure is followed. These experiments provide direct evidence of a neurochemical "coding" within the specific anatomical region of the brain historically implicated in the control of body temperature.  相似文献   

Losartan, an AT1 antagonist, prevents aortic aneurysm in a mouse model of Marfan syndrome     

Habashi JP  Judge DP  Holm TM  Cohn RD  Loeys BL  Cooper TK  Myers L  Klein EC  Liu G  Calvi C  Podowski M  Neptune ER  Halushka MK  Bedja D  Gabrielson K  Rifkin DB  Carta L  Ramirez F  Huso DL  Dietz HC 《Science (New York, N.Y.)》2006,312(5770):117-121

Aortic aneurysm and dissection are manifestations of Marfan syndrome (MFS), a disorder caused by mutations in the gene that encodes fibrillin-1. Selected manifestations of MFS reflect excessive signaling by the transforming growth factor-beta (TGF-beta) family of cytokines. We show that aortic aneurysm in a mouse model of MFS is associated with increased TGF-beta signaling and can be prevented by TGF-beta antagonists such as TGF-beta-neutralizing antibody or the angiotensin II type 1 receptor (AT1) blocker, losartan. AT1 antagonism also partially reversed noncardiovascular manifestations of MFS, including impaired alveolar septation. These data suggest that losartan, a drug already in clinical use for hypertension, merits investigation as a therapeutic strategy for patients with MFS and has the potential to prevent the major life-threatening manifestation of this disorder.  相似文献   

Detecting reproductive system abnormalities of broiler breeder roosters at different ages          下载免费PDF全文

MA Lagares  R Ecco  NRS Martins  LJC Lara  JSR Rocha  DAR Vilela  VM Barbosa  PF Mantovani  JFV Braga  IS Preis  VA Gheller  PC Cardeal  NC Baião 《Reproduction in domestic animals》2017,52(1):67-75

The objective of this study was to detect the reasons of rooster's fertility decrease at 50 weeks of age. Therefore, the reproductive system of broiler breeder roosters was laparoscopic, macroscopic and histopathology evaluated, and a comparison of the anatomical aspect with the sperm analysis and birds’ age was realized. Cobb roosters (n = 59) were distributed into two groups (30 and 50 weeks). Evaluations were performed with laparoscopy, macroscopy and histopathology, and seminal quality, blood serum testosterone concentration and weight were also determined. The old roosters presented smaller testicle size, higher intensity epididymal lithiasis and lower testicle sperm production, compared to the young roosters. The use of the endoscope could easily distinguish a normal‐sized testicle than an atrophic one. Four old roosters with severe testicular atrophy did not show spermatogenesis, although three still had sperm in the ejaculate. This would falsely indicate a wrong diagnosis of normal fertility before the testicular atrophy took place. In conclusion, in addition to the weight increase with age, the testicular atrophy and impairment of sperm production seemed to be the main reason to the decrease in the rooster's fertility at 50 weeks of age. Therefore, the use of the laparoscopy as a way to detect the roosters with testicular atrophy before 50 weeks of age and their removal from them flock could be useful as a diagnostic tool to prevent the birds’ fertility loss.  相似文献   

Tetravalent uranium in calcite   总被引：1，自引：0，他引：1  

NC Sturchio  MR Antonio  L Soderholm  SR Sutton  JC Brannon 《Science (New York, N.Y.)》1998,281(5379):971-973

X-ray absorption spectroscopy and x-ray fluorescence microprobe studies of 35-million-year-old calcite from a Mississippi Valley-type zinc ore deposit indicate substitution of tetravalent uranium for divalent calcium. Thus, tetravalent uranium has a stable location in calcite deposited under reducing conditions. This result validates uranium-series dating methods (including uranium/lead dating) for ancient calcite and shows that calcite provides a sink for uranium in deep groundwater aquifers and anoxic lacustrine and marine basins.  相似文献   

Differences in benthic cover inside and outside marine protected areas on the Great Barrier Reef: influence of protection or disturbance history?     

Monique R. Myers  Richard F. Ambrose 《水产资源保护:海洋与淡水生态系统》2009,19(7):736-747

• 1. Marine protected areas (MPAs) are being used increasingly to manage and protect marine resources. Most studies of MPAs have focused on fish. In this study, the influence of MPA protection on coral reef benthic organisms on the Great Barrier Reef (GBR) was investigated. In addition, the interaction between protection and natural disturbance history was examined.
• 2. Differences in benthic cover inside and outside MPAs were assessed at 15 pairs of Protected and General Use reefs on the GBR using annual monitoring data from the Australian Institute of Marine Science's Long‐Term Monitoring Programme (LTMP). At each reef, benthic cover was determined using a benthic video survey at three sites, with each site consisting of five 50 m transect lines separated by at least 250 m running parallel to the reef crest at 6–9 m depth.
• 3. Benthic cover was related to both protection status and disturbance history, but natural perturbations exerted a stronger influence on benthic cover than did protection status. The influence of natural perturbation was most noticeable for hard coral.
• 4. Most reefs where no natural disturbance events had occurred (‘undisturbed reefs’) had higher hard coral cover and lower soft coral cover than General Use reefs. While the high levels of hard coral on Protected reefs may be a result of protection status, it might also have resulted from selection bias that occurred during the initial zoning of the Great Barrier Reef Marine Park (i.e. managers may have given protection status to reefs with high coral cover).
• 5. These results are likely influenced by the relatively low intensity of human use, both on the Great Barrier Reef in general and at the particular monitoring sites studied. Over time, as local populations and tourism increase, the effect of protection may become more evident at LTMP sites. Copyright © 2009 John Wiley & Sons, Ltd.

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