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1.

Synthesis of 2,2,3-tris(hydroxymethyl)methylenecyclopropane analogues 16a, 16b, 17a, and 17b is described. Diethyl ester of Feist's acid 18b was hydroxymethylated via carbanion formation using formaldehyde under simultaneous isomerization to cis diester to give intermediate 19. Reduction followed by acetylation gave triacetate 22. Addition of bromine afforded reagent 23, which was used for alkylation-elimination of adenine and 2-amino-6-chloropurine to provide Z,E-isomeric mixtures of 24a and 24b. Deacetylation and separation furnished the Z-isomers 16a, 16c and E-isomers 17a, 17c. Hydrolytic dechlorination of 16c and 17c gave guanine analogues 16b and 17b. None of the analogues exhibited a significant antiviral activity. Adenosine deaminase is refractory toward adenine analogues 16a and 17a.  相似文献   

2.
ABSTRACT

Background: Pallenis spinosa (Asteraceae) produces both winged and wingless achenes. Both achene morphs are non-dormant and show a similar embryo size, rendering dispersal ability as their only apparent functional difference.

Aims: We studied morph-specific release and spatial dispersal patterns to ascertain whether the common view of seed dimorphism as a mixed strategy, that is functionally fully differentiated morphs, is appropriate for this system.

Methods: For three years, at the onset of achene release, in early autumn, we placed achene traps at different distances from source plants, censusing achene arrival at 3–4 day intervals. We constructed morph-specific dispersal kernels and related release intensity to prevailing meteorological conditions in census intervals. Selected kernel models were used to describe dispersal effects of observed changes in the proportion of winged achenes (pw) in successive released fractions.

Results: Achene release extended up to early-mid winter, peaking in rainy, windy intervals. Throughout the season, pw decreased progressively. Unexpectedly, the wingless morph produced the longest dispersal tails and it only showed ability for fat-tailed dispersal. Consequently, maximum dispersal distances steadily increased throughout the season.

Conclusions: Achene dimorphism in P. spinosa appears to allow a within-season continuous reshaping of the seed-dispersal kernel instead of representing a mixed strategy.  相似文献   

3.
Abstract

In this work the expression of functional ribonuclease T1 on the surface of the filamentous Escherichia coli phage M13 is described. Ribonuclease T1 was fused to the phage coat protein pIII and functionally displayed on the phage surface as shown by a negative staining zymogram and RNase indicator plates.  相似文献   

4.
Summary

The subtidal marine algal flora of Sullom Voe was reassessed in 1983 after an interval of ten years. Only a few changes in communities were detected; these, not surprisingly, were at sites of major coastal engineering works.  相似文献   

5.
Abstract

This paper deals with the synthesis of a new type of N-labeled peptidyl AMP, which would be used as a good substrate for analysis of the peptidyl transfer reaction on ribosome and for co-crystallization with ribosome. 4-(Dimethylamino)azobenzene-4′-sulfonyl (Dabsyl) was selected as the labeling group. (N-Dabsylglycyl)-L-leucyl AMP was synthesized from glycyl-L-leucine via a three-step procedure.  相似文献   

6.
《Plains anthropologist》2013,58(11):13-20
Abstract

In the literature various theories of culture change have been developed relevant to the Dakota Indians. These theories of change can be grouped under the headings of psychological, social, and cultural change.

Psychologically the changes in Dakota personality are seen as developing from the child-rearing process. Social change has been regarded as reflecting the changing values within the family circle due to pressure from white culture. Culture change has been hypothesized as due to indoctrination in the Dakota value system during childhood. It is this persistence of Dakota values which is the main deterrent to the acceptance of many non-Indian skills.  相似文献   

7.
Abstract

The preparation of monomers for the synthesis of phosphonate analogues of peptide nucleic acids containing the four natural nucleobases: thymine, cytosine, adenine and guanine, has been ccomplished. The monomers obtained were used for the automated online solid phase synthesis of pure phosphono-PNA oligomers as well as chimeras consisting of phosphono-PNA and PNA resudies. The hybridization properties of these oligonucleotide mimics to complementary DNA and RNA fragments were studied.  相似文献   

8.
《Plains anthropologist》2013,58(73):225-229
Abstract

A computer encoding device known as a RAND Tablet can be applied in archeological researchto read off of an artifact, such as a flint projectile point, certain points of data that when used by a computer program to provide measurements from the artifact, can provide a basis for classification.  相似文献   

9.
ABSTRACT

Reaction of glycosyl isothiocyanate 1a-c with 3-indolylaminomethyl-ketone hydrochloride(2) yielded glycosylthiourea derivatives 3a-c. Cyclodehydration of 3a-c with acetic anhydride afforded 5-(indol-3-yl)-2-[N-per-O-acetyl-D-glycopyranosyl)amino]thiazoles 4a-c. Deacetylation of 4a-c gave 5-(indol-3-yl)-2-[N-(D-glycopyranosyl) amino]thiazoles 5a-c.  相似文献   

10.
《Endocrine practice》2015,21(3):275-279
ObjectiveInjectable osteoporosis drugs are increasing in popularity due to their efficacy and convenient administration. In this retrospective comparison of the two available treatments, denosumab (Prolia®) and zoledronic acid (ZA, Reclast®), we aimed to determine and compare the efficacy and tolerability of denosumab and ZA.MethodsThe charts of patients who received denosumab and ZA at Loyola Hospital were reviewed, and adverse events were noted. Of primary interest were myalgias, flu-like symptoms, back pain, and fractures. A questionnaire regarding the efficacy, tolerability, and treatment cost supplemented this chart review in a subset of study participants. Bone mineral density (BMD) changes, bone turnover markers, and questionnaire results were also compared.ResultsThe study cohort consisted of 107 patients (51 denosumab, 56 ZA). The denosumab group had a greater mean increase in spine BMD at 1 year (0.060 g/cm2) than the ZA group (0.021 g/cm2; P = .04). The change in femur and spine BMD at 1 year were not significantly different between the 2 groups. The ZA group had a significantly greater incidence of mild flu-like symptoms (29% ZA group vs. 0% denosumab group; P = .04).ConclusionThe denosumab group had a higher mean increase in spine BMD, and the ZA group had a higher incidence of flu-like symptoms, but the study groups were statistically similar in terms of patient satisfaction. As denosumab is still a relatively new therapy, there were a limited number of patients with posttreatment data available for comparison. As more posttherapy data become available, it can be further investigated. (Endocr Pract. 2015;21:275-279)  相似文献   

11.
《Endocrine practice》2004,10(3):199-202
ObjectiveTo describe two cases of human immunodeficiency virus (HlV)-infected patients who had diabetes mellitus, which resolved after initiation of antiretroviral therapy.MethodsWe present the clinical and laboratory findings and describe the clinical course of these two patients.ResultsA 48-year-old HIV-infected black woman presented with multiple infections and hyperglycemia. After her acute infections were treated and she was feeling well, she continued to have diabetes that necessitated insulin therapy. Administration of a protease inhibitor-based antiretroviral regimen resolved her diabetes and eliminated the need for insulin or oral therapy. Our second patient, a 37-year-old HIV-infected black man, presented with polyuria and polydipsia and a hemoglobin A1c value of 11%. He received antiretroviral therapy, and his diabetes resolved after a period of months.ConclusionProtease inhibitor-based antiretroviral therapy is associated with diabetes mellitus in up to 6% of HIV-infected patients. Although most HIV-infected patients in whom diabetes develops have this disorder after initiation of protease inhibitor therapy, the current two cases illustrate patients in whom diabetes resolved after use of antiretroviral therapy. This finding supports the presence of other mechanisms that affect glucose metabolism in patients infected with HIV and suggests that control of HIV infection may have a role in controlling diabetes. (Endocr Pract. 2004;10:199-202)  相似文献   

12.
《Endocrine practice》2008,14(8):1020-1022
ObjectiveTo describe a case of severe neuropathy associated with hypertriglyceridemia.MethodsWe describe the clinical and laboratory findings of the study patient and review the relevant literature.ResultsA 45-year-old woman presented to the emergency department with recurrent abdominal pain and severe peripheral neuropathy. Her laboratory data revealed elevated lipase and a very high triglyceride concentration (> 10 000 mg/dL), consistent with a diagnosis of recurrent hypertriglyceridemia-induced pancreatitis. Workup for peripheral neuropathy showed normal concentrations of thyrotropin, fasting blood glucose, vitamin B12, and creatinine, as well as a normal hemoglobin A1c level, serum protein electrophoresis, and urine protein electrophoresis. Rapid plasma reagin antibodies, antinuclear antibodies, and lyme antibodies were not detected. In the absence of other identifiable causes, hypertriglyceridemia was deemed the likely etiology of severe neuropathy in this patient.ConclusionsPeripheral nerve conduction abnormalities can be identified in patients with mild hypertriglyceridemia in the absence of symptoms. Early recognition and aggressive management of hypertriglyceridemia may prevent the complications of severe peripheral neuropathy.(Endocr Pract. 2008;14:1020-1022)  相似文献   

13.
《Plains anthropologist》2013,58(19):52-60
Abstract

Quillwork among the Indian tribes of the Northwest as practised by the women embodied features of religious significance of a restrictive nature, Only a few women had the right to do this work and it was they who gave permission for others to be initiated into the religious pattern. The symbolisms, while varying between tribes, included specific prayers, face and hand painting and the wearing of specific ornaments, such as necklaces, while quilling. Quill work was done in return for gifts and the finished product could not be sold. Designs could be used only by the owner unless they were given away.  相似文献   

14.
《Endocrine practice》2008,14(7):832-839
ObjectiveTo assess the safety, adverse effects, and radioactive iodine uptake (RAIU) of recombinant human thyrotropin (rhTSH) using a range of doses in patients with multinodular goiters.MethodsIn this open-label study conducted between June 2002 and December 2004, euthyroid patients with small nontoxic multinodular goiters and normal thyrotropin concentrations were recruited from 4 sites in the United States. Baseline assessments included thyroid function tests, electrocardiogram, Holter monitoring, hyperthyroid symptom scale, flow-volume loop, and measurement of thyroglobulin and thyroperoxidase antibodies. Patients had a baseline 24-hour scan and thyroid iodine I 123 (123I) uptake evaluated at 6, 24, and 48 hours after rhTSH administration. Each patient received a single intramuscular injection of 0.03-mg, 0.1-mg, or 0.3-mg rhTSH followed 24 hours later by 400 μCi 123I orally. Iodine 123 uptakes were again measured 6, 24, and 48 hours later, and a scintigram scan was performed at 24 hours. Thyroid function tests, flow-volume loop, Holter monitoring and/or electrocardiograms, and thyroid ultrasonography to assess thyroid size were performed serially.ResultsTwenty-eight patients participated. Median goiter size was 20 mL (range, 7-79 mL). After each rhTSH dose, the radioiodine uptake approximately doubled at each time point compared with baseline uptake. Small rises in serum thyroxine and triiodothyronine were seen in some patients, especially after 0.3-mg rhTSH, and mild symptoms of hyperthyroidism developed in several patients. Flow-volume loop showed transient, mild asymptomatic worsening in 1 patient with a 35.2 mL goiter, although thyroid volume measurements were unchanged. Minor electrocardiogram and/or Holter changes were seen in several patients.ConclusionsA flat dose-response curve exists over the range of rhTSH doses tested, with an approximate doubling of thyroid RAIU. All patients tolerated rhTSH well, but the rise in thyroid hormone levels and adverse effects after rhTSH doses of 0.1 mg or higher theoretically might not be well tolerated in older or sicker patients and appear unjustified given the lack of a greater rise in RAIU compared with the 0.03-mg dose. Future studies evaluating rhTSH doses less than 0.1 mg in patients with multinodular goiter are justified. (Endocr Pract. 2008;14:832-839)  相似文献   

15.
《Plains anthropologist》2013,58(83):35-38
Abstract

The assumption of complexity seems to dominate much of anthropological thinking. This is clearly indicated by the frequency of use of complex multivariate statistics such as factor analysis. It is argued here that human behavior may often be much simpler than assumed and that the optimal approach to data analysis is to assume simplicity until demonstrated otherwise. It is also argued that when multivariate statistics are used, they are most effectively used in a deductive framework.  相似文献   

16.
《Plains anthropologist》2013,58(73):187-197
Abstract

The Hutterites of North America are often envied by their rural neighbors as being efficient and productive agriculturalists who combine twentieth century technology with a life stylereminiscent of an earlier age. A closer examination of Hutterice culture reveals that a tension exists between these two elements.  相似文献   

17.

The influence of incubation time and Fenton reagent concentrations was investigated on the oxidation of 2′-deoxyguanosine. The compounds identified and quantified, through use of an LC-MS/MS system, were 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and 8,5′-cyclo-2′-deoxyguanosine (8,5′cyclodG) and the secondary oxidation products guanidinohydantoin and dehydro-guanidinohydantoin. 8-oxodG and 8,5′cyclodG formed very quickly, reaching a maximum rapidly, but with 8-oxodG a rapid decline occurred thereafter due to its further oxidation into the secondary products, which formed more slowly. Due to the better stability, 8,5′cyclodG correlated better with the general level of oxidation than 8-oxodG. The results emphasize the advantages of measuring other oxidation adducts than 8-oxodG alone.  相似文献   

18.
Abstract

The discovery of interferon in 1957 by Drs. Alick Isaacs and Jean Lindenmann led to major revisions in the concepts of man's defenses against viral infections. Interferons are well known as inhibitors of virus replication. This inhibition is accomplished by acting on the host cell rather than on the virus (Figure 1). The proposed biological mediator of the antiviral action of interferon is not interferon, but an antiviral protein, which is produced by a cell after that cell has come into contact with interferon.  相似文献   

19.
Summary

The discovery of the fern Cystopteris dickieana Sim in Kincardineshire (the type locality of the species) during the mid- nineteenth century, an its supposed extirpation only twelve years after being first brought to public notice is described. The background to its apparent disappearance and subsequent reappearance are examined.  相似文献   

20.
For EPR measurements of RNA, DNA, or proteins, the occurrence of the paramagnetic species is necessary. The aim of this work is to improve the synthesis of two different EPR spinlabels 2,2,6,6-tetra methyl-3,4-dehydro-piperidin-N-oxyl-4-acetylene (TEMPA) 6 and 15N-labeled TEMPA 6* and their coupling to uridine. The yield of the synthesis of TEMPA could be increased to 40% and the second nitroxide 2,2,6,6-tetramethyl-3,4-dehydro-piperidin-15N-oxyl-4-acetylene 6* could be synthesized with a yield of 11%.  相似文献   

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