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1.
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.  相似文献   
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用体内外实验模型,研究了新维A类化合物4-乙酰胺苯基维A酸酯(4-APR)对肿瘤侵袭、转移的抑制作用。4-APR 43.3mg·kg-1po即能减少小鼠Lewis肺癌的自发性肺转移瘤数。半体内实验证明4-APR10-5mol·L-1和10-6mol·L-1对B16-F10癌细胞的人工肺转移瘤数分别抑制67.9%和36.6%。体外实验显示,4-APR对B16-F10细胞侵袭重组基底膜的抑制率分别为54.2%和41.9%。  相似文献   
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Background:

Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.

Materials and Methods:

Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.

Results:

All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.

Conclusion:

Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group.  相似文献   
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BackgroundThe combination of preoperative deficiencies and the restrictions and malabsorption possibly induced by bariatric surgery could lead patients to experience important nutritional deficits during the late postoperative period. Our objective was to characterize the eating, anthropometric, and biochemical profiles of obese candidates for bariatric surgery at a bariatric surgery center of a university hospital.MethodsA retrospective study with the analysis of medical records of candidates for bariatric surgery from 2007 to 2008 was performed. A total of 80 adult patients, aged 45 ± 11 years, were included in the present study.ResultsThe mean patient weight was 145 ± 24 kg, and the mean body mass index was 54 ± 8 kg/m2. Of the 80 patients, 78% had ≥1 co-morbidities related to obesity. The reported daily energy intake before surgery was 1981 ± 882 kcal, with 48% ± 11% consisting of carbohydrate, 29% ± 8% of lipids, and 23% ± 8% of protein. The mean number of daily meals was 4 ± 1. Patients with a greater body mass index ingested a smaller amount of calories per kilogram of current weight. The occurrence of hyperglycemia, hyperuricemia, and dyslipidemia and of nutritional deficiencies, among them magnesium (19%), vitamin A (15%), vitamin C (16%), iron (9%), β-carotene (3%), and vitamin B12 (3%), was high.ConclusionThe high occurrence of micronutrient deficiency detected by biochemical analysis in morbidly obese candidates for bariatric surgery, representing a disabsorptive process, might involve a poorer prognosis during the late postoperative period. A preoperative evaluation of the nutritional parameters and the food intake pattern is recommended for these patients, together with the necessary interventions.  相似文献   
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The secret is comprised in three words – work, finish, publish.’Michael FaradayThere are many reasons doctors want to publish their work. For most at an early stage in their career, this may be to add a line to their curriculum vitae and advance their careers but for academics, publishing is an expectation. Many will believe they have something important to say, and wish to provoke debate and discussion; others wish to share knowledge and experiences, which in medicine can lead to a satisfying change in clinical practice. All serve to register one’s idea and educate others. However, for some, the reason is as basic as money. As we celebrate the 350th anniversary of the first academic publication, perhaps we have come full circle when it comes to why people publish?Publishing is a flourishing business. There were approximately 28,100 active scholarly peer-reviewed journals in mid-2012, collectively publishing about 1.8–1.9 million articles per year. The number of articles published each year and the number of journals have both grown steadily for more than two centuries, by about 3% and 3.5% per year respectively.1 Journals have a responsibility to refine and define information and act as a scientific filter. Many of us will receive daily invitations in our email inbox from eclectic and new journals that are likely to take anything – is the filter now too porous? But this industry is like any other commercial activity and the supply still far outstrips the demand. Perhaps the internet revolution has merely fuelled our hunger to publish more?The launch of this exciting and innovative series about publishing coincides with the 350th celebration of the publication of the first academic journal. In the age of social media, the first question is ‘What are journals for?’, which Simon Rallison sets out to answer. Simon is Director of Publications at the Physiological Society, and was previously a journal publisher with Earthscan, Springer and Blackwell.Writing is hard work and, through this series, I hope the reader will get some useful insight into this service industry for academia.Jyoti ShahCommissioning EditorIn an age of the internet and social media, why are we still using (admittedly with refinements and improvements) a form of publication dating from 1665? What exactly is a journal in the 21st century and what role does it have to perform? Surprisingly, the academic journal has not evolved since it was invented 350 years ago.1 The first issue of the Philosophical Transactions of the Royal Society was published in 1665, the brainchild of Henry Oldenburg and Robert Hooke. Since then, journals have digitised and now offer greater opportunity for research communication – but are authors taking advantage of what journals can offer? The academic and research community is generally very conservative about what it reads and how it views journals. There are, however, also frequent misunderstandings about the operation of journals.  相似文献   
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Fetal persistent middle cerebral artery reversed end diastolic flow is a rare and ominous finding. Previous cases have been associated with intracranial hemorrhage, growth restriction, anaemia, and hepatic anomaly. Intrauterine demise or early neonatal death is a common outcome. We report the case of persistent middle cerebral artery reversed end diastolic flow in a well-grown fetus at 32 weeks’ gestation resulting from acute, severe anaemia due to a large feto-maternal hemorrhage. An emergency cesarean section was performed and the neonate required advanced resuscitation and immediate blood transfusion. Postnatal magnetic resonance imaging confirmed a hemorrhagic parietal infarct and bilateral ischaemic changes in the basal ganglia. This provides further evidence that persistent middle cerebral artery reversed end diastolic flow in any fetus is an ominous finding warranting urgent diagnostic evaluation and/or delivery.  相似文献   
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Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
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