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1.
Two cases of squamous cell carcinoma of the prepuce arising on balanitis xerotica obliterans are described. This event is unusual and not well known. The surgical treatment was a wide circumcision in which the prepuce and part of the shaft skin were removed, performing as well a decortication of the glans base. This technique seemed to be satisfactory in removing the carcinoma and obtaining a definite improvement in the clinical picture of balanitis xerotica obliterans as well.  相似文献   
2.
The solid-state photo-CIDNP (photochemically induced dynamic nuclear polarization) effect is studied in photosynthetic reaction centers of Heliobacillus mobilis at different magnetic fields by 13C MAS (magic-angle spinning) NMR spectroscopy. Two active states of heliobacterial reaction centers are probed: an anaerobic preparation of heliochromatophores (“Braunstoff”, German for “brown substance”) as well as a preparation of cells after exposure to oxygen (“Grünstoff”, “green substance”). Braunstoff shows significant increase of enhanced absorptive (positive) signals toward lower magnetic fields, which is interpreted in terms of an enhanced differential relaxation (DR) mechanism. In Grünstoff, the signals remain emissive (negative) at two fields, confirming that the influence of the DR mechanism is comparably low.  相似文献   
3.
Abstract

As a part of an ongoing nationwide programme focused on finding novel strains of Bacillus thuringiensis (Bt) that are toxic to some of the major pests that impact economically important crops, we initiated a search for Bt isolates native to Syria. We succeeded in assembling a collection of 40 Bt isolates recovered from infected larvae of Galleria mellonella, Helicoverpa armigera and Ephestia kuehniella. Light microscopy showed that all isolates produce bipyramidal and cuboidal crystal proteins. The 50% lethal concentration of the spore-crystal mixture of the 40 isolates against E. kuehniella larvae varied from 3 to more than 200 µg g?1. A comparison of the LC50 values of the tested isolates with the reference strain Bt kurstaki HD-1 (20.55 µg g?1), showed that some of these isolates have a similar or up to six times higher toxicity potential. PCR screening revealed that all obtained isolates contain cry1 and cry2 genes, whereas only four contain cry9. Moreover, the proteins of 130 and 65/70 Kda encoded by these genes were detected in the SDS-PAGE of the purified parasporal bodies. Flagellar serotyping classified 30 as serovar kurstaki, six isolates serovar aizawai, one isolate cross-reacted with more than one H3 antisera and three were not typeable. Assays of toxicity of the aizawai isolates against third instar of G. mellonella showed that four, which contain cry9, have almost similar toxicity to the commercial strain Bt aizawai B401. Therefore, these isolates could be adopted for future applications to control G. mellonella. Moreover, this study contributes to our knowledge of Bt diversity in Syria where to date very few collections have been described.  相似文献   
4.

Background

The Centers for Disease Control and Prevention recommends nontargeted opt-out HIV screening in healthcare settings. Cost effectiveness is critical when considering potential screening methods. Our goal was to compare programmatic costs of nontargeted opt-out rapid HIV screening with physician-directed diagnostic rapid HIV testing in an urban emergency department (ED) as part of the Denver ED HIV Opt-Out Trial.

Methods

This was a prospective cohort study nested in a larger quasi-experiment. Over 16 months, nontargeted rapid HIV screening (intervention) and diagnostic rapid HIV testing (control) were alternated in 4-month time blocks. During the intervention phase, patients were offered HIV testing using an opt-out approach during registration; during the control phase, physicians used a diagnostic approach to offer HIV testing to patients. Each method was fully integrated into ED operations. Direct program costs were determined using the perspective of the ED. Time-motion methodology was used to estimate personnel activity costs. Costs per patient newly-diagnosed with HIV infection by intervention phase, and incremental cost effectiveness ratios were calculated.

Results

During the intervention phase, 28,043 eligible patients were included, 6,933 (25%) completed testing, and 15 (0.2%, 95% CI: 0.1%–0.4%) were newly-diagnosed with HIV infection. During the control phase, 29,925 eligible patients were included, 243 (0.8%) completed testing, and 4 (1.7%, 95% CI: 0.4%–4.2%) were newly-diagnosed with HIV infection. Total annualized costs for nontargeted screening were $148,997, whereas total annualized costs for diagnostic HIV testing were $31,355. The average costs per HIV diagnosis were $9,932 and $7,839, respectively. Nontargeted HIV screening identified 11 more HIV infections at an incremental cost of $10,693 per additional infection.

Conclusions

Compared to diagnostic testing, nontargeted HIV screening was more costly but identified more HIV infections. More effective and less costly testing strategies may be required to improve the identification of patients with undiagnosed HIV infection in the ED.  相似文献   
5.

Aims

To describe and to characterize clinical features of latent autoimmune diabetes in adults (LADA) compared to type 1 and type 2 diabetes in the UAE.

Methods

In this cross-sectional study a dataset including 18,101 subjects with adult-onset (>30 years) diabetes was accessed. 17,072 subjects fulfilled the inclusion/exclusion criteria. Data about anthropometrics, demographics, autoantibodies to Glutamic Acid Decarboxylase (GADA) and to Islet Antigen 2 (anti-IA2), HbA1c, cholesterol and blood pressure were extracted. LADA was diagnosed according to GADA and/or anti-IA2 positivity and time to insulin therapy.

Results

437 (2.6%) patients were identified as LADA and 34 (0.2%) as classical type 1 diabetes in adults. Mean age at diagnosis, BMI, waist circumference, systolic blood pressure and HbA1c significantly differed between, LADA, type 2 and type 1 diabetes, LADA showing halfway features between type 2 and type 1 diabetes. A decreasing trend for age at diagnosis and waist circumference was found among LADA subjects when subdivided by positivity for anti-IA2, GADA or for both antibodies (p=0.013 and p=0.011 for trend, respectively). There was a gradual downward trend in autoantibody titre in LADA subjects requiring insulin within the first year from diagnosis to subjects not requiring insulin after 10 years of follow-up (p<0.001).

Conclusions

This is the first study describing the clinical features of LADA in the UAE, which appear to be different from both type 1 and type 2 diabetes. Furthermore, we showed that the clinical phenotype of LADA is dependent on different patterns of antibody positivity, influencing the time to insulin requirement.  相似文献   
6.
The global human population is expected to reach ∼9 billion by 2050. Feeding this many people represents a major challenge requiring global crop yield increases of up to 100%. Microbial symbionts of plants such as arbuscular mycorrhizal fungi (AMF) represent a huge, but unrealized resource for improving yields of globally important crops, especially in the tropics. We argue that the application of AMF in agriculture is too simplistic and ignores basic ecological principals. To achieve this challenge, a community and population ecology approach can contribute greatly. First, ecologists could significantly improve our understanding of the determinants of the survival of introduced AMF, the role of adaptability and intraspecific diversity of AMF and whether inoculation has a direct or indirect effect on plant production. Second, we call for extensive metagenomics as well as population genomics studies that are crucial to assess the environmental impact that introduction of non-local AMF may have on native AMF communities and populations. Finally, we plead for an ecologically sound use of AMF in efforts to increase food security at a global scale in a sustainable manner.  相似文献   
7.
This article is a summary report of the international conference "Forest ecosystem genomics and adaptation" organized by the EVOLTREE Network of Excellence in San Lorenzo de El Escorial (Madrid), Spain, from 9 to 11 June 2010. Main achievements and results of the network are presented for the eight thematic sessions and a stakeholder session. The conference has shown that adaptive responses of trees to biotic or abiotic selection pressures can now be investigated at the gene level for traits of adaptive significance. Candidate genes have been catalogued for phenological and drought-related traits in important tree families (Salicaceae, Fagaceaea and Pinaceae), and their variation in natural populations is being explored. Genomics can now be integrated in ecological research to investigate evolutionary response to climate changes in a wide range of species. New avenues of research were also highlighted as the exploration of gene networks involved in adaptive responses and the combination of experimental and modelling approaches to disentangle components of evolutionary changes triggered by climate change. The main focus of the conference was the adaptation of trees to environmental changes. The conference was organized in eight thematic sessions ranging from genomic approaches aiming at identifying genes of adaptive significance to practical issues regarding mitigation options for combating climate change. A dialogue between scientists and end users took place in the form of an ad hoc stakeholder session. A panel of end users from various forest and policy-making institutions expressed their expectations, and the discussions with the scientists addressed the potential applications of research findings to the management of genetic resources in the context of climate changes. The conference was introduced by two keynote speakers Dr. Pierre Mathy from the European Commission, Directorate General of Research, and Dr. Allen Solomon, former National Program Leader for Global Change, US Forest Service. All the thematic sessions were introduced by high-level invited speakers from the respective fields.  相似文献   
8.
Hurricane‐caused tree mortality in tropical dry forests occurs predominantly in early successional species. Consequently, hurricanes may accelerate succession in these forests. Forest regeneration, however, must be measured over an extended posthurricane time period to demonstrate this pattern. In this study, we recorded tree seedlings in 19 Florida Keys forests during May–August 1995, 3 years after Hurricane Andrew. For these forests—spanning a chronosequence from 14 to over 100 years since the most recent clearing—we used weighted averaging regression on relative abundances of pre‐hurricane trees to calculate a successional age optimum for each species; and used weighted averaging calibration to calculate inferred successional ages for stands based on pre‐hurricane trees and on posthurricane seedlings. To test the hypothesis that successional stage of seedlings exceeded successional stage of pre‐hurricane trees, we compared inferred stand ages based on posthurricane seedlings with those based on pre‐hurricane trees. Across the study area, inferred stand ages based on posthurricane seedlings were greater than those based on pre‐hurricane trees (P < 0.005); however, more seedlings in the youngest stands were early successional than in older stands. Of 29 species present both as pre‐hurricane trees and posthurricane seedlings, 23 had animal‐dispersed seeds. These results provide evidence that: (1) hurricanes do not ‘reset’ succession, and may accelerate succession; and (2) a strong legacy of stand successional age influences seedling assemblages in these forests.  相似文献   
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