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51.
Our knowledge of mitochondrial biology has advanced significantly in the last 10 years. The effects of mitochondrial dysfunction or cytopathy (MC) on the heart and neuromuscular system are well known, and its involvement in the pathophysiology of several common clinical disorders such as diabetes, hyperlipidaemia and hypertension, is just beginning to emerge; however, its contribution to renal disease has received much less attention, and the available literature raises some interesting questions: Why do children with MC commonly present with a renal phenotype that is often quite different from adults? How does a mutation in mitochondrial DNA (mtDNA) lead to disease at the cellular level, and how can a single mtDNA point mutation result in such a variety of renal- and non-renal phenotypes in isolation or combined? Why are some regions of the nephron seemingly more sensitive to mitochondrial dysfunction and damage by mitochondrial toxins? Perhaps most important of all, what can be done to diagnose and treat MC, now and in the future? In this review we summarize our current understanding of the relationship between mitochondrial biology, renal physiology and clinical nephrology, in an attempt to try to answer some of these questions. Although MC is usually considered a rare defect, it is almost certainly under-diagnosed. A greater awareness and understanding of kidney involvement in MC might lead to new treatment strategies for diseases in which mitochondrial dysfunction is secondary to toxic or ischaemic injury, rather than to an underlying genetic mutation.  相似文献   
52.
The effect of barium on blood in the gastrointestinal tract   总被引:2,自引:0,他引:2  
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54.
IntroductionWe assessed the practice of surgeons regarding venous thromboembolism (VTE) chemical prophylaxis for total hip replacement (THR) and total knee replacement (TKR), before and after issuing of updated National Institute for Health and Care Excellence (NICE) guidance in 2018.MethodsA survey, circulated through the British Hip Society and regional trainee networks/collaboratives, was completed by 306 UK surgeons at 187 units. VTE chemical prophylaxis prescribing patterns for surgeons carrying out primary THR (n=258) and TKR (n=253) in low-risk patients was assessed after publication of 2018 NICE recommendations. Prescribing patterns before and after the NICE publication were subsequently explored.ResultsFollowing the new guidance, 34% (n=87) used low-molecular-weight heparin (LMWH) alone, 33% (n=85) aspirin (commonly preceded by LMWH) and 31% (n=81) direct oral anticoagulants (DOACs: with/without preceding LMWH) for THR. For TKR, 42% (n=105) used aspirin (usually monotherapy), 31% (n=78) LMWH alone and 27% (n=68) DOAC (with/without preceding LMWH). NICE guidance changed the practice of 34% of hip surgeons and 41% of knee surgeons, with significantly increased use of aspirin preceded by LMWH for THR (before=25% vs after=73%; p<0.001), and aspirin for TKR (before=18% vs after=84%; p<0.001). Significantly more regimens were NICE guidance compliant after the 2018 update for THR (before=85.7% vs after=92.6%; p=0.011) and TKR (before=87.0% vs after=98.8%; p<0.001).ConclusionOver one-third of surveyed surgeons changed their VTE chemical prophylaxis in response to 2018 NICE recommendations, with more THR and TKR surgeons now compliant with latest NICE guidance. The major change in practice was an increased use of aspirin for VTE chemical prophylaxis.  相似文献   
55.

Background

Cryptosporidium is a worldwide protozoan parasite and one of the most common causes of infection and diarrhea in humans and cattle. The aim of the present study was determination of subtypes of Cryptosporidium among children with diarrhea in Tehran by sequence analysis of the highly polymorphic 60-kDa glycoprotein (GP60) gene.

Methods

Fecal samples were collected from 794 diarrheic children. Initial identification of Cryptosporidium was carried out on stool samples by Ziehl-Neelsen acid-fast staining method. DNA was extracted from positive microscopically samples and Cryptosporidium genotypes and subtypes were determined, accordingly.

Results

Out of 794 collected samples, 19 (2.40%) were positive for Cryptosporidium oocysts. Sequences analysis of GP60 gene showed that 17 (89.47%) of the positive isolates were Cryptosporidium parvum and 2 (10.52%) were C. hominis. All subtypes of C. parvum isolates belonged to allele families IIa (6/17) and IId (11/17). The most common allele in all 17 isolates belonged to IId A20G1a (41.18%). A22G1 (IF) subtype was detected in two C. hominis isolates of the children.

Conclusion

The predominancy of C. parvum species (specially, IId A20G1a subtype) in current study underlines the importance of zoonotic Cryptosporidium transmission in Iran.  相似文献   
56.
口服Carvedilol治疗心力衰竭多中心研究(MOCHA)   总被引:1,自引:0,他引:1  
标题 Carvedilol对慢性心力衰竭患者左心室功能的改善和存活的提高呈剂量相关性作者 BristowMR,GilbertEM,AbrahamWT,等  Circulation1996,94:2807~2816  研究疾病:充血性心力衰竭。目的:对Carvedilol治疗慢性心力衰竭患者剂量-疗效特征进行评价。  设计:随机、双盲、安慰剂对照的多中心研究,剂量效应关系研究。病人资料:共345名心力衰竭患者,年龄18~85岁,左室射血分数≤0-35,心力衰竭症状时间≥3月,研究前所有患者必须用利…  相似文献   
57.
Volumetric rendering of MR images   总被引:1,自引:0,他引:1  
The authors developed new techniques for three-dimensional display of magnetic resonance (MR) images that preserve soft-tissue definition, are fully automatic, and work with routinely used section thicknesses. MR images are segmented, selectively enhanced, and displayed by means of a volumetric rendering algorithm. These techniques were used to illustrate normal anatomy of the brain, knee, and liver. Three-dimensional rendering of balanced spin-echo images shows the ventricles and extracerebral veins and of T1-weighted images, the sulci and gyri. The large hepatic and portal vessels can be seen with these enhancement techniques. Three-dimensional views of the knee reveal articular surfaces of the tibia and clearly depict menisci and posterior and anterior cruciate ligaments. These techniques make it possible to image multiple soft tissues simultaneously while preserving the detail contained in the original images. Three-dimensional presentation of complex, overlapping anatomic regions is helpful in surgical planning and should lead to improved diagnosis.  相似文献   
58.
59.
Pulmonary manifestations of AIDS: review of 106 episodes   总被引:9,自引:0,他引:9  
Suster  B; Akerman  M; Orenstein  M; Wax  MR 《Radiology》1986,161(1):87-93
We reviewed the clinical records and chest radiographs of all patients admitted to our institution between 1982 and 1984 who had pulmonary disease and who were later proved to have acquired immunodeficiency syndrome (AIDS) (95 patients). Diffuse parenchymal lung disease was the most common finding. These infiltrates were usually interstitial and caused by Pneumocystis carinii pneumonia or P. carinii combined with cytomegalovirus infection. Focal, multilobar, interstitial infiltrates were also often seen and usually caused by P. carinii or P. carinii and cytomegalovirus infections. Rarely, well-defined, multiple, interstitial nodules less than 10 mm in diameter were the only or predominant characteristic and were seen only in association with Mycobacterium tuberculosis or Cryptococcus neoformans infections or Kaposi sarcoma. Hilar or mediastinal adenopathy occurred in 17 of the 21 patients with M. tuberculosis or C. neoformans infections. In contrast, only 4% of patients with P. carinii infections presented with these findings. We also found that hilar or mediastinal adenopathy was not significantly associated with peripheral adenopathy. Lung cavitation, pleural effusion, or a normal chest radiograph was uncommon.  相似文献   
60.
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