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Mumby PJ Harborne AR Williams J Kappel CV Brumbaugh DR Micheli F Holmes KE Dahlgren CP Paris CB Blackwell PG 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(20):8362-8367
Reduced fishing pressure and weak predator-prey interactions within marine reserves can create trophic cascades that increase the number of grazing fishes and reduce the coverage of macroalgae on coral reefs. Here, we show that the impacts of reserves extend beyond trophic cascades and enhance the process of coral recruitment. Increased fish grazing, primarily driven by reduced fishing, was strongly negatively correlated with macroalgal cover and resulted in a 2-fold increase in the density of coral recruits within a Bahamian reef system. Our conclusions are robust because four alternative hypotheses that may generate a spurious correlation between grazing and coral recruitment were tested and rejected. Grazing appears to influence the density and community structure of coral recruits, but no detectable influence was found on the overall size-frequency distribution, community structure, or cover of corals. We interpret this absence of pattern in the adult coral community as symptomatic of the impact of a recent disturbance event that masks the recovery trajectories of individual reefs. Marine reserves are not a panacea for conservation but can facilitate the recovery of corals from disturbance and may help sustain the biodiversity of organisms that depend on a complex three-dimensional coral habitat. 相似文献
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Sarcomatoid renal carcinoma represents 1-5% of primitive tumours of the kidney. MATERIALS AND METHODS. A young man aged 34 presented with left side colic pain, preceded two days earlier by hematuria without pain; no previous complaints. Echotomography was performed revealing a tumour lesion of the upper left renal pole, which was subsequently confirmed by computerized tomography scanning, with a maximum diameter of approximately 6cm, and evidence of multiple lymph nodes with increased volume. A left-side nephroadrenalectomy was performed with locoregional lymphadenectomy; a sarcomatoid renal carcinoma with massive metastases in 4/19 excised lymph nodes was shown through histological examination. IL-2 therapy was commenced but interrupted due to intolerance. After only three months the disease resumed locally with diffuse lymph nodes metastases and multiple encephalic metastases. A carboplatinum and vinorelbine therapy was started; the possibility of an allogeneic transplant with non-myeloablative conditioning ("miniallogeneic") was suggested, though being impossible to be performed due to the further rapid disease progression. The patient died after approximately 10 months. CONCLUSIONS. Sarcomatoid renal carcinoma is characterised histologically by closely interconnected epithelial and connective tissue elements; sarcomatous cells seem to originate from a phenotype conversion to carcinomatous cells, as they both belong to the same DNA clone. Their behaviour is very aggressive and the prognosis is unfavourable: 6-month average survival after diagnosis. Radical nephrectomy is still the main therapeutic approach, although it is has no significant influence on prognosis and survival rate. This case showed an approximately 10-month patient's survival, with some different chemotherapeutic approaches being followed (first IL-2 and then carboplatinum) after surgery. 相似文献
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Open reduction and internal fixation is the treatment of choice in distal humerus fractures. The aims of the treatment are
to obtain anatomic reconstruction and restoration of the elbow’s geometry followed by stable internal fixation that allows
immediate rehabilitation. The plates are pre-contoured to fit the natural anatomy of the elbow and in the case of complex
fractures they provide a guide for the anatomic restoration of the distal humerus. The two plates are placed parallel with
the screws locked together by interdigitation creating a fixed angle in the distal fragments that provides stability to the
entire distal humerus. Using this method we obtained good results according to the Mayo Elbow Performance Score (MEPS) and
we are able to reduce the incidence of complications. Our experience shows also that it can be useful to obtain an anatomical
reduction of distal humeral fractures using the pre-contoured plates in a parallel position recovering the anatomical antiversion
of the articular surface. 相似文献
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Giubilei G Mondaini N Minervini A Saieva C Lapini A Serni S Bartoletti R Carini M 《The Journal of urology》2007,177(1):159-165
PURPOSE: Chronic prostatitis/chronic pelvic pain syndrome is a major healthcare burden. Affected patient quality of life is poor and currently no investigated treatments have significant long-term benefit. We performed a preliminary investigation of the role of physical activity and its effects on select patients with chronic prostatitis/chronic pelvic pain syndrome. MATERIALS AND METHODS: Between 2002 and 2004 we recruited a volunteer sample of 231 eligible males 20 to 50 years old with chronic prostatitis/chronic pelvic pain syndrome who were unresponsive to conventional treatments and free of any contraindication for moderate intensity physical exercise. This group was screened and, if in accordance with study inclusion/exclusion criteria, patients were randomized into 2 groups. Participants were randomly assigned to the aerobic exercise group (52) and the placebo/stretching and motion exercises group (51). Main outcome measures were the Italian version of the National Institutes of Health Chronic Prostatitis Symptom Index, Beck Depression Inventory, State Anxiety Inventory-Y and a pain intensity visual analog scale administered at baseline, and 6 and 18 weeks. RESULTS: At 18 weeks 36 subjects (75%) in the aerobic exercise group vs 40 (81.63%) in the placebo/stretching and motion exercises group completed the 18-week program and evaluation. Differences between the 2 groups were found in total National Institutes of Health Chronic Prostatitis Symptom Index, pain and quality life impact subscales, and pain visual analog score (ANCOVA p = 0.006, 0.0009, 0.02 and 0.003, respectively). CONCLUSIONS: Improvements in the aerobic exercise group were significantly superior compared to those in the placebo/stretching and motion exercises group. Aerobic exercise represents a valid treatment option and it should be further investigated in a larger study with longer followup. 相似文献