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71.
72.
We have isolated the cDNA and corresponding genomic DNA encoding citrate synthase in Neurospora crassa. Analysis of the protein coding region of this gene, named cit-1, indicates that it specifies the mitochondrial form of citrate synthase. The predicted protein has 469 amino acids and a molecular mass of 52002 Da. The gene is interrupted by four introns. Hybridization experiments show that a cit-1 probe binds to two different fragments of genomic DNA, which are located on different chromosomes. Neurospora crassa may have two isoforms of citrate synthase, one in the mitochondria and the other in microbodies.  相似文献   
73.

Introduction

Gastro-oesophageal reflux disease (GORD) is a common problem in the Western countries, and the interest in the minimal access surgical approaches to treat GORD is increasing. In this study, we would like to discuss the presentations and management of complications we encountered after Laparoscopic Nissen's fundoplication in our District General NHS Hospital. The aim is to recognise these complications at the earliest stage for effective management to minimise the morbidity and mortality.

Methods

301 patients underwent laparoscopic treatment for GORD by a single consultant surgeon in our NHS Trust from September 1999. The data was prospectively collected and entered into a database. The data was retrospectively analysed for presentations for complications and their management.

Results

Surgery was completed laparoscopically in all patients, except in five, where the operation was technically difficult due to pre-existing conditions. The complications we encountered during surgery and follow-up period were major intra-operative bleeding (n = 1, 0.33%), severe post-operative nausea and vomiting (n = 1, 0.33%), wound infection (n = 3, 1%), port-site herniation (n = 1, 0.33%), wrap-migration (n = 2, 0.66%), wrap-ischaemia (n = 1, 0.33%), recurrent regurgitation (n = 4, 1.32%), recurrent heartburn (n = 29, 9.63%), tension pneumothorax (n = 2, 0.66%), surgical emphysema (n = 8, 2.66%), and port-site pain (n = 4, 1.33%).

Conclusion

Minimal access approach to treat GORD has presented with some specific and unique complications. It is important to recognise these complications at the earliest possible stage as some of these patients may present in an acute setting requiring emergency surgery. All members of the department, and not just the members of the specialised team, should be aware about these complications to minimise the morbidity and mortality.  相似文献   
74.
The effect of in vitro incubation on the level of the intracellular nucleophile, glutathione (GSH), in adult Schistosoma mansoni was investigated. The GSH levels of freshly collected adult male and female parasites were 8.5 +/- 2.5 and 2.7 +/- 0.7 nmol/10 worms, respectively, as determined by an enzymatic assay. Twenty-four-hour incubation of unpaired males in RPMI-1640 medium at 37 C resulted in a 1.7-fold increase (P less than 0.001) in GSH level that remained elevated for at least 7 days. The increase was dependent on exogenous L-cystine, suggesting that it was due to biosynthesis of GSH. Biosynthesis in male S. mansoni was confirmed by isolating [3H] GSH from parasites incubated in medium containing L-[3H] cystine or [3H] glycine. In contrast to unpaired males, the GSH level of paired males as well as that of unpaired or paired females did not increase after 24 hr in vitro. When males that had been incubated unpaired for 24 hr were allowed to couple in vitro with freshly collected females, their GSH level fell to that of continuously paired males. These observations provide evidence that in vitro female schistosomes can influence the physiology of the male.  相似文献   
75.
Due to limited data available on the presence of antibiotic-resistant (ABR) bacteria in faeces of wild herbivores in South Africa, this study analysed resistance patterns for Escherichia coli isolates from wildebeest, zebra and giraffe in addition to pet and farm pig faeces. Total and faecal coliforms and E. coli were quantified in faecal matter using a most probable number (MPN) guideline procedure. Antibiotic resistance profiles against 12 selected antibiotics representing seven classes were determined for 30 randomly selected E. coli isolates from each animal using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) disk diffusion procedure. While log10 MPN values per gram of animal faeces for total/faecal coliforms ranged from 4.51/4.11 to 5.70/5.50, the E. coli MPN values were in a range of 3.43–5.14. The proportion of ABR E. coli isolates ranged from 43% (giraffe) to 93% (zebra). About 47% of E. coli isolates from zebra faeces were categorized as multidrug-resistant (MDR), while for wildebeest and giraffe, no MDR isolates were detected. In comparison, 10% of E. coli isolates from pet pig and about 7% from farm pig faeces were categorized as MDR. Although most MDR isolates were resistant to at least one β-lactam antibiotic, only one MDR isolate from farm pig faeces was resistant to both norfloxacin and ciprofloxacin, the two fluoroquinolones tested. However, no resistance was detected to the tested carbapenems and tigecycline. The results of this study indicate that indigenous South African herbivores may serve as potential reservoirs and vectors for the dissemination of ABR E. coli strains.  相似文献   
76.

Background

New HIV infections in men who have sex with men (MSM) have increased in Switzerland since 2000 despite combination antiretroviral therapy (cART). The objectives of this mathematical modelling study were: to describe the dynamics of the HIV epidemic in MSM in Switzerland using national data; to explore the effects of hypothetical prevention scenarios; and to conduct a multivariate sensitivity analysis.

Methodology/Principal Findings

The model describes HIV transmission, progression and the effects of cART using differential equations. The model was fitted to Swiss HIV and AIDS surveillance data and twelve unknown parameters were estimated. Predicted numbers of diagnosed HIV infections and AIDS cases fitted the observed data well. By the end of 2010, an estimated 13.5% (95% CI 12.5, 14.6%) of all HIV-infected MSM were undiagnosed and accounted for 81.8% (95% CI 81.1, 82.4%) of new HIV infections. The transmission rate was at its lowest from 1995–1999, with a nadir of 46 incident HIV infections in 1999, but increased from 2000. The estimated number of new infections continued to increase to more than 250 in 2010, although the reproduction number was still below the epidemic threshold. Prevention scenarios included temporary reductions in risk behaviour, annual test and treat, and reduction in risk behaviour to levels observed earlier in the epidemic. These led to predicted reductions in new infections from 2 to 26% by 2020. Parameters related to disease progression and relative infectiousness at different HIV stages had the greatest influence on estimates of the net transmission rate.

Conclusions/Significance

The model outputs suggest that the increase in HIV transmission amongst MSM in Switzerland is the result of continuing risky sexual behaviour, particularly by those unaware of their infection status. Long term reductions in the incidence of HIV infection in MSM in Switzerland will require increased and sustained uptake of effective interventions.  相似文献   
77.
78.
Traumatic injuries can be used as general indicators of activity patterns in past populations. This study tests the hypothesis that contemporaneous (10th–12th century) rural and urban populations in medieval Poland will have a significantly different prevalence of non-violent fractures. Traumatic injuries to the post-cranial skeleton were recorded for 180 adults from rural Giecz and for 96 adults from urban Poznań-Śródka. They were statistically analyzed by body region and individual skeletal element. Results reveal that Giecz had a significantly higher rate of trunk fractures than Poznań-Śródka (Fisher’s exact, p<0.05). In particular, rib and vertebral fractures were more common in Giecz males and females than in their Poznań-Śródka counterparts. Traumatic injuries in the extremities were comparable between the two samples, suggesting similar risks of trauma to these regions. These results indicate that in early medieval Poland, activities associated with a rural lifestyle resulted in more injuries. These stress or accidental fractures, which are related to a high-risk setting, were not consistent with an urban lifestyle. Overall, agricultural populations like Giecz were engaged in a laborious lifestyle, reflected in a variety of injuries related to repetitive, high-risk activities. Although urban populations like Poznań engaged in craft specialization participated in repetitive activities, their lifestyle resulted in lesser fracture-risk.  相似文献   
79.
The influence of plant interference and a mild drought on gas exchange and oxidative stress was investigated using potted plants of two cotton species (Gossypium hirsutum L. cv. Delta Pine 5415, and Gossypium barbadense L. cv. Pima S-7) and spurred anoda (Anoda cristata L. Schlecht.) of the Malvaceae. Without interference, cotton and spurred anoda had similar net photosynthesis (Pnet) but different pigment profiles. Stomatal conductance (gs) and transpiration rate (E) were greater in spurred anoda than cotton. Net photosynthesis and biomass in cotton were reduced more by spurred anoda interference than by intraspecific interference. With interference, the xanthophyll cycle conversion state and alpha-tocopherol levels increased in cotton, but remained unchanged in spurred anoda. Catalase, ascorbate peroxidase (APX) and glutathione reductase (GR) activities were not influenced by plant interference. Without interference, spurred anoda had lower APX, and similar catalase and GR activities compared with cotton. Mild drought increased APX activity more than 40% in cotton, and 26% in spurred anoda. Upon drought recovery, drought-induced APX activity was still higher in cotton, and GR activity was higher in previously drought-stressed cotton and spurred anoda plants compared with well-watered plants. The greater impact of spurred anoda interference than intraspecific interference on cotton biomass is due mainly to reduced carbon gain in cotton.  相似文献   
80.

Objectives

Several studies have investigated potential functional signals in the trabecular structure of the primate proximal humerus but with varied success. Here, we apply for the first time a “whole‐epiphyses” approach to analysing trabecular bone in the humeral head with the aim of providing a more holistic interpretation of trabecular variation in relation to habitual locomotor or manipulative behaviors in several extant primates and Australopithecus africanus.

Materials and methods

We use a “whole‐epiphysis” methodology in comparison to the traditional volume of interest (VOI) approach to investigate variation in trabecular structure and joint loading in the proximal humerus of extant hominoids, Ateles and A. africanus (StW 328).

Results

There are important differences in the quantification of trabecular parameters using a “whole‐epiphysis” versus a VOI‐based approach. Variation in trabecular structure across knuckle‐walking African apes, suspensory taxa, and modern humans was generally consistent with predictions of load magnitude and inferred joint posture during habitual behaviors. Higher relative trabecular bone volume and more isotropic trabeculae in StW 328 suggest A. africanus may have still used its forelimbs for arboreal locomotion.

Discussion

A whole‐epiphysis approach to analysing trabecular structure of the proximal humerus can help distinguish functional signals of joint loading across extant primates and can provide novel insight into habitual behaviors of fossil hominins.
  相似文献   
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