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1.

Background

A recent study argued, based on data on functional genome size of major phyla, that there is evidence life may have originated significantly prior to the formation of the Earth.

Results

Here a more refined regression analysis is performed in which 1) measurement error is systematically taken into account, and 2) interval estimates (e.g., confidence or prediction intervals) are produced. It is shown that such models for which the interval estimate for the time origin of the genome includes the age of the Earth are consistent with observed data.

Conclusions

The appearance of life after the formation of the Earth is consistent with the data set under examination.

Reviewers

This article was reviewed by Yuri Wolf, Peter Gogarten, and Christoph Adami.  相似文献   

2.
Psychromonas ingrahamii, named for John L. Ingraham, was isolated from sea ice from off Point Barrow, Alaska. This large rod-shaped bacterium belongs to the gamma-Proteobacteria. P. ingrahamii is a psychrophilic, heterotrophic bacterium that is gas vacuolate and nonmotile. P. ingrahamii is notable in that it grows at a temperature of –12°C with a generation time of 240 h. This is the lowest growth temperatures of any organism authenticated by a growth curve. Jim Staley has enjoyed exploring the diversity of the microbial world, especially that of the budding and prosthecate bacteria as well as polar microorganisms, alongside Peter Hirsch during many years of friendship and collaboration. Happy 75th, Peter!  相似文献   

3.
The larva of the hermit crab Diogenes nitidimanus Terao, 1913 was found in the ballast waters of the tanker Minotaur that arrived from the Chinese port of Laizhou (Bohai Bay, Yellow Sea). Earlier, an abundant population of mature adults of D. nitidimanus was found in Vostok Bay (Peter the Great Bay), this suggested the introduction and naturalization of this species in the Peter the Great Bay. The finding of its larva in ballast waters of a ship on the Russia-China route confirms the introduction of this species into Peter the Great Bay.  相似文献   

4.
This study of the deep-sea red snow crab Chionoecetes japonicus is based on materials that were collected from its poorly surveyed or earlier unknown habitats in the central Sea of Japan, including the KitaYamato Bank and the top of the Peter the Great Seamount, during a research cruise aboard the R/V Vladimir Safonov in April and May of 2012. The results are compared to the data of the previous studies aboard the fishing vessels Seisho-maru 68 (September and October 1992), Viera (May and June 2005), and the Arctic Orion (April and May 2007). The red snow crab stock on the Kita-Yamato Bank has declined by one-third within 2 decades. Both males and females formed the densest aggregations at depths of 800–1040 m. The total biomass of legal-sized males in 2012 is estimated at 7400 t. The first data on red snow crab that inhabit the top of Peter the Great Seamount show that its total biomass over the area of 1.5 km2 is 14 t. The mean carapace size of crabs from the Peter the Great Seamount is smaller (males, 83.0 mm and females, 58.6 mm) than that of individuals from the Kita-Yamato Bank (males, 99.9 mm and females, 65.0 mm).  相似文献   

5.
Research on the physiological mechanisms of finger temperature biofeedback with normal subjects and Raynaud's disease patients is reviewed. Studies conducted in the author's laboratory have shown that feedback-induced vasodilation is mediated through a non-neural, -adrenergic mechanism rather than through reductions in sympathetic nervous system activation. In contrast, feedback-induced vasoconstriction is mediated through the traditional, sympathetic nervous pathway. When used with primary Raynaud's disease patients, feedback-induced vasodilation has achieved reductions in reported symptom frequency ranging from 66% to 92% in controlled investigations. Future research directions are discussed.Research conducted by the author was supported by research grants Nos. HL-23828, HL-30604, and AG-05233 from NIH. I am grateful for the collaboration of the following colleagues during the 14 years of work reported here: Peter Ianni, Dena Norton, Paul Wenig, Subhash Sabharwal, Maureen Mayes, Nagraj Desai, Michael Morris, Peter Migály, and Stewart Vining.  相似文献   

6.
Cellularization of a precellular ancestral condition of life must have occured separately for each of the three domains of life resulting in a protoarchaeon, a protobacterium and a protocaryon. Accordingly, a first cell, ancestral to the three domains of life has never existed. This statement is based on a retrospective evaluation of the distribution patterns of membrane lipids and of cell wall polymers with their different chemical nature and modes of biosynthesis in a global phylogenetic tree based on 16S rRNA sequence comparison.Dedicated to Professor Peter Sitte on the occasion of his 65th birthday.  相似文献   

7.
《Endocrine practice》2014,20(5):461-462
Objective: BRAF mutations are the most common genetic alteration found in papillary thyroid carcinoma (PTC). Approximately, 90% correspond to BRAFV600E, although other less common BRAF mutations have been described. The aim of this study was to describe a new mutation on BRAF gene discovered on the previous thyroid cytology of a patient diagnosed with a follicular variant of PTC (FV-PTC).Methods: The mutation was identified by independent cloning of the 2 alleles and direct sequencing in the

Pheochromocytoma and Tetralogy of Fallot: a Rare But Potentially Dangerous Combination

Rajeev Kasaliwal; Vijaya Sarathi; Reshma Pandit; Sweta R. Budyal; Amol Bukan; Harshal Kakade; Varsha S. Jagtap; Anurag R. Lila; Tushar Bandgar; Padmavathy S. Menon; Nalini S. Shah

Hypercalcemia and Acromegaly – Clarifying the connections: A Case Report and Review of the Literature

Pooja Manroa; Subramanian Kannan; Betul Hatipoglu; Angelo Licata

A Case of “Late-Onset” Idiopathic Infantile Hypercalcemia Secondary to Mutations in the Cyp24a1 Gene

Peter Wolf; Thomas Müller-Sacherer; Sabina Baumgartner-Parzer; Yvonne Winhofer; Judit Kroo; Alois Gessl, Anton Luger; Michael Krebs
  相似文献   

8.
Concentrations of heavy metals Fe, Mn, Cu, Zn, Pb, Cd, and Ni were determined in the thalluses of the green alga Ulva fenestrata sampled from different locations in Peter the Great Bay (Sea of Japan). According to the metal concentrations in Ulva, the degree of pollution of the surveyed areas in Peter the Great Bay decreases in the following series: Amur Bay > Ussuri Bay > Nakhodka Bay > Vostok Bay > the water area of Far Eastern State Marine Nature Biosphere Reserve. The microelement composition of Ulva from open-shore stations reflects the heavy metal pollution level of water areas as a whole. The concentrations of trace elements in U. fenestrata from closed coastal areas are indicative of marine coastal water pollution from local sources. Generally, metal concentrations in U. fenestrata from Peter the Great Bay are similar to heavy metal levels in non-polluted or weakly polluted coastal areas of the world.  相似文献   

9.
In a series of works, Peter Carruthers has argued for the denial of the title proposition. Here, I defend that proposition by offering direct support drawn from relevant sciences and by undercutting Carruthers argument. In doing the latter, I distinguish an intrinsic theory of consciousness from Carruthers relational theory of consciousness. This relational theory has two readings, one of which makes essential appeal to evolutionary theory. I argue that neither reading offers a successful view.  相似文献   

10.
The spinning apparatus of the Haplogynae was studied in cribellate and ecribellate families of this group. Profound differences were encountered between the species investigated. It is concluded that the group of the Haplogynae is polyphyletic and can not be maintained in a phylogenetic system of the Araneae.

Sonderdruckanforderungen an: Prof. Dr. Peter Ax II. Zoologisches Institut und Museum der Universität D-3400 Göttingen Berliner Str. 28 Deutschland  相似文献   

11.
Kleger, Gian-Reto, Peter Bärtsch, Peter Vock, BernhardHeilig, L. Jackson Roberts II, and Peter E. Ballmer. Evidence against an increase in capillary permeability in subjects exposed tohigh altitude. J. Appl. Physiol.81(5): 1917-1923, 1996.A potential pathogenetic cofactor for thedevelopment of acute mountain sickness and high-altitude pulmonaryedema is an increase in capillary permeability, which could occur as aresult of an inflammatory reaction and/or free radical-mediatedinjury to the lung. We measured the systemic albumin escape byintravenously injecting 5 µCi of 125I-labeled albumin and theplasma concentrations of cytokines, F2-isoprostanes (products of lipidperoxidation), and acute-phase proteins in 24 subjects exposed to 4,559 m. Ten subjects developed acute mountain sickness, and four subjectsdeveloped high-altitude pulmonary edema. The transcapillary escaperate of albumin was 6.9 ± 2.0%/h (SD) at low (550 m) and 6.3 ± 1.9%/h at high (4,559 m) altitude (P = 0.23; n = 24). The subjects withhigh-altitude pulmonary edema had a modest but insignificant increasein the transcapillary escape rate of albumin (4.6 ± 1.9%/h at lowvs. 5.7 ± 1.9%/h at high altitude;P = 0.42;n = 4). Plasma concentrations offibrinogen, 1-acidglycoprotein, C-reactive protein, and interleukin-6 were unchanged inthe early phases and significantly increased by the end of theobservation period in the subjects with high-altitude pulmonary edema,whereas tumor necrosis factor- andF2-isoprostanes did not change atall. This suggests that the inflammatory reaction was rather aconsequence than a causative factor of high-altitude pulmonary edema.In summary, these data argue against a dominant role for increasedsystemic capillary permeability in the development of acute mountainsickness and high-altitude pulmonary edema.

  相似文献   

12.

Background

Due to significant limitations to the access to orthotropic liver transplantation, cell therapies for liver diseases have gained large interest worldwide.

Scope of review

To revise current literature dealing with cell therapy for liver diseases. We discussed the advantages and pitfalls of the different cell sources tested so far in clinical trials and the rationale underlying the potential benefits of transplantation of human biliary tree stem cells (hBTSCs).

Major conclusions

Transplantation of adult hepatocytes showed transient benefits but requires immune-suppression that is a major pitfall in patients with advanced liver diseases. Mesenchymal stem cells and hematopoietic stem cells transplanted into patients with liver diseases are not able to replace resident hepatocytes but rather they target autoimmune or inflammatory processes into the liver. Stem cells isolated from fetal or adult liver have been recently proposed as alternative cell sources for advanced liver cirrhosis and metabolic liver disease. We demonstrated the presence of multipotent cells expressing a variety of endodermal stem cell markers in (peri)-biliary glands of bile ducts in fetal or adult human tissues, and in crypts of gallbladder epithelium. In the first cirrhotic patients treated in our center with biliary tree stem cell therapy, we registered no adverse event but significant benefits.

General significance

The biliary tree stem cell could represent the ideal cell source for the cell therapy of liver diseases. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.  相似文献   

13.
The application of nondestructive methods such as video-transects and photo-quadrates to epifaunal communities of hard bottoms of Peter the Great Bay is analyzed in the present work. It was shown that video-transects gave more representative material than photo-quadrates for a greater area of scope. Two ways of transect shooting were considered, and a modified technique of counting the projective cover of the substrate by invertebrates with application of color segmentation and AutoCAD® software is suggested. The advantages and drawbacks of video- and photo-methods of epibenthos counting are considered.Original Russian Text Copyright © 2005 by Biologiya Morya, Tkachenko.  相似文献   

14.
Ohne ZusammenfassungAusgeführt mit Unterstützung der Universität zu Stockholm, der Stiftung Lars Hiertas Minnesfond, der Verwaltung für Peter Wahlbergs fond, der Königlichen Landwirtschaftsakademie und Längmanska Kulturfonden. Die Arbeit erscheint aus technischen Gründen in wesentlich gekürzter Form.  相似文献   

15.
The state of marine and estuary organisms living in the polluted coastal zone of Peter the Great Bay in the Sea of Japan has been estimated using molecular biomarkers of oxidative stress and biotransformation that characterize changes in animal metabolism under the effect of pollutants. The integral biochemical indices were calculated and graphically represented for mussels Crenomytilus grayanus collected at marine stations with different degrees of pollution and for the Japanese mitten crab Eriocheir japonica from the estuaries of rivers flowing into Peter the Great Bay, based on statistical processing of the results. It has been noted that the values of the indices correspond to the degree of pollution of animal sampling areas.  相似文献   

16.

Background

Autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis represent the three major autoimmune liver diseases (AILDs). Their management is highly specialized, requires a multidisciplinary approach and often relies on expensive, orphan drugs. Unfortunately, their treatment is often unsatisfactory, and the care pathway heterogeneous across different centers. Disease-specific clinical outcome indicators (COIs) able to evaluate the whole cycle of care are needed to assist both clinicians and administrators in improving quality and value of care. Aim of our study was to generate a set of COIs for the three AILDs. We then prospectively validated these indicators based on a series of consecutive patients recruited at three tertiary clinical centers in Lombardy, Italy.

Methods

In phase I using a Delphi method and a RAND 9-point appropriateness scale a set of COIs was generated. In phase II the indicators were applied in a real-life dataset.

Results

Two-hundred fourteen patients were enrolled and followed-up for a median time of 54 months and the above COIs were recorded using a web-based electronic medical record program. The COIs were easy to collect in the clinical practice environment and their values compared well with the available natural history studies.

Conclusions

We have generated a comprehensive set of COIs which sequentially capture different clinical outcome of the three AILDs explored. These indicators represent a critical tool to implement a value-based approach to patients with these conditions, to monitor, compare and improve quality through benchmarking of clinical performance and to assess the significance of novel drugs and technologies. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.  相似文献   

17.
Until COVID‐19, coronaviruses were largely overlooked by virologists. Yet, their abundance in mammalian species could cause new spillover events into humans. Subject Categories: Ecology, Microbiology, Virology & Host Pathogen Interaction

By now, coronaviruses have become notorious. Yet, before the SARS coronaviruses started wreaking havoc with human society, coronaviruses were largely overlooked, even amongst virologists. “When I told another virologist at a meeting what I was working on”, recalled Peter Rottier at Utrecht University, the Netherlands, who began his coronavirus research in 1979, “that person said they''d never heard of coronaviruses”. With plenty of other viruses such as influenza and HIV demanding attention, funders saw no reason to support research on the endemic human coronaviruses in the 1980s and 1990s since they caused mostly common cold.
With plenty of other viruses such as influenza and HIV demanding attention, funders saw no reason to support research on the endemic human coronaviruses in the 1980s and 90s…
Clinicians and virologists began taking much notice around 2003 and 2004 after the SARS coronavirus inflicted about 800 deaths before the outbreak receded, but the potential of this virus family to spillover into new species and mutate to more virulent strains had long been recognized by veterinarians, because coronaviruses inflict significant diseases in poultry, cattle and especially pigs. Virologists now are taking a closer look at some of these diseases to better understand coronaviruses and why they may be relevant for potential future pandemics.  相似文献   

18.
Comparison of the results of ichthyoplankton surveys conducted at 97 stations in the eastern part of the Peter the Great Bay of the Sea of Japan, in June–July 2007 with the similar research data of the 1950s shows that at present, as was the case 50 years ago, flatfish eggs belonging mainly to the yellowfin sole Limanda aspera and brown sole Pleuronectes herzensteini prevail in the local ichthyoplankton (up to 86%). The highest concentrations of these species’ eggs were recorded in the Vostok Bay and Strelok Bay. The spawning activity of flatfish in 2007 is found to be lower than in the mid 1900s, but the significance of the eastern part of the Peter the Great Bay for flatfish reproduction remains large. The importance of long-term monitoring in this area, which is being subjected to steadily growing anthropogenic impacts, is also proven.  相似文献   

19.
The distribution and growth of the bivalve mollusk Protothaca euglypta in Peter the Great Bay and at the northern boundary of its area were investigated. It is shown that in some biotopes P. euglypta biomass reaches 1–2 kg/m2, which exceeds the estimated values of abundance obtained for most associated species of mollusks. It has been established that local variability of P. euglypta growth rates can be compared with latitudinal variability, and the life span increases from the southern part of the area towards its northern boundary. It has been concluded that P. euglypta occupies a more prominent position in the malacofauna of shallow waters in its abundance, than it was considered earlier.  相似文献   

20.
The finding of the shortfin lizardfish Saurida microlepis Wu et Wang, 1931 in Peter the Great Bay of the Sea of Japan makes a contribution to the ichthyofauna of the Russian waters with a new family Synodontidae.  相似文献   

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