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排序方式: 共有373条查询结果,搜索用时 15 毫秒
51.
M. Honkinen E. Lahti R. Österback O. Ruuskanen M. Waris 《Clinical microbiology and infection》2012,18(3):300-307
Few comprehensive studies have searched for viruses and bacteria in children with community-acquired pneumonia (CAP). We identified 76 children hospitalized for pneumonia. Induced sputum samples were analysed for 18 viruses by antigen detection and PCR, and for six bacteria by culture and PCR. Viruses were found in 72% of samples, bacteria in 91%, and both in 66%. Rhinovirus (30%), human bocavirus (18%) and human metapneumovirus (14%) were the most commonly detected viruses. Two viruses were found in 22% of samples and three in 8%. The most common bacteria found were Streptococcus pneumoniae (50%), Haemophilus influenzae (38%), and Moraxella catarrhalis (28%). Rhinovirus–S. pneumoniae was the most commonly found combination of virus and bacterium (16%). All six children with treatment failure had both viruses and bacteria detected in the sputum. Otherwise, we found no special clinical characteristics in those with mixed viral–bacterial detections. With modern molecular diagnostic techniques, there are high rates of both viral and bacterial identification in childhood CAP. The clinical significance of mixed viral–bacterial infections remains unclear, although we found a potential association between them and treatment failure. 相似文献
52.
Study Type – Diagnostic (retrospective cohort) Level of Evidence 2b What’s known on the subject? and What does the study add? The results of ICSI using fresh or frozen sperm on the site of sperm retrieval remains controversial with respect to outcome. The results of this study showed no difference in outcome using ICSI either with respect to the site of retrieval or whether the sperm used was fresh or frozen. It also showed that the outcome of ICSI is not related to the underlying cause of the azoospermia.
OBJECTIVES
? To compare the outcome of first‐attempt intracytoplasmic sperm injection (ICSI) ICSI–embryo transfer (ET) cycles using frozen‐thawed testicular sperm (FTTS), fresh testicular sperm (FTS), frozen‐thawed epididymal sperm (FTES) and fresh epididymal sperm (FES) so as to determine which of these has the most successful ICSI outcome with respect to fertilization rate (FR), pregnancy rate (PR) and birth rate. ? To assess the outcomes according to the underlying aetiology of azoospermia.PATIENTS AND METHODS
? The records of 493 patients undergoing first‐attempt ICSI between 1993 and 2008 were reviewed retrospectively. FTS was used in 112 cycles, FTTS in 43 cycles, FES in 279 cycles, and FTES in 59 cycles. ? Within each group, the aetiology of the azoospermia was recorded according to history, clinical examination and histological analysis (n= 316). ? The FR, clinical PR and delivery rate were calculated for each group with respect to the type of sperm retrieval used.RESULTS
? Analysis of the data showed no significant differences between any of the four groups in the FR, PR or delivery rate (P > 0.05). ? There were no significant differences seen between fresh sperm (FTS and FES) and frozen sperm (FTTS and FTES) or between epididymal sperm (FES and FTES) and testicular sperm (FTS and FTTS) in any of the outcomes measured (P > 0.05). However, sub‐set analysis showed a statistically higher FR and PR for FTTS over fresh sperm. ? When comparing aetiologies, there was no significant difference in the FR, clinical PR and delivery rate between obstructive azoospermia (OA) and non‐obstructive azoospermia (NOA) groups. However, sub‐set analysis showed a higher PR and birth rate for FTTS over fresh sperm in both OA and NOA groups.CONCLUSIONS
? The results of the present study suggest that using frozen sperm in ICSI cycles is a reliable and favourable method with the same outcome as fresh sperm. ? Testicular and epididymal sperm have similar ICSI outcomes for both fresh and frozen samples. However, results suggest a tendency for higher PRs and birth rates for frozen than for fresh testicular sperm in both OA and NOA aetiologies. ? The aetiology of azoospermia does not significantly affect the outcome of first‐attempt ICSI. The higher rates in the frozen groups suggest that these patients have had better quality semen when they were initially harvested and frozen. 相似文献53.
Emotional difficulties have been observed in individuals with eating disorders across awide range of studies, including poor interoceptive awareness, confusion of emotional states and difficulties with emotional language. Literature has linked these difficulties with emotional functioning as being an important factor related to the core aetiology ofeating disorders, however limited knowledge exists to how this impacts on professionalability to engage patients within treatment as a result of such dysfunction. Using aqualitative design this paper explores how facets of Emotional intelligence (EI) are related to the experience of an eating disorder. The study sampled a total of 32 participants with either a professional background working with eating disorders (n=27)or participants with personal lived experience (n=5), with a number of the participants (n=13) identified as having dual roles. The findings of the study show that aspects of EIsuch as emotional regulation and lack of an emotional language are considered to beat the core of the onset and maintenance of these disorders. Additional aspects of emotional awareness and expression were found to be related to treatment disengagement and difficulties. Building on previous literature, this paper found suchemotional deficits as a transdiagnostic issue rather than specifically anorexia nervosa. Furthermore, such dysfunction was seen by professionals to have a considerable impact on therapeutic relationships and successful treatment. These findings provide insight into the potential applications that EI may have in addressing aspects of theeating disorder to create better outcomes for treatment and intervention models. 相似文献
54.
Background
10% of patients who undergo a cholecystectomy go on to develop post-cholecystectomy syndrome (PCS). The majority of these patients may suffer from extra-biliary or unrelated organic disorders that may have been present before cholecystectomy. The numerous aetiological causes of PCS result in a wide spectrum of management options, each with varying success in abating symptoms. This systematic review aims to provide a summary of the causative aetiologies of post cholecystectomy syndrome, their incidences and efficacy of available management options.Methods
The Medline, Embase and Cochrane databases were searched for studies patients who developed PCS symptoms following laparoscopic cholecystectomy, published between 1990 and 2016. The aetiology, incidence and management options were extracted, with separate collation of randomised control trials and non-randomised studies that reported intervention. Outcomes included recurrent symptoms following intervention, unscheduled primary and secondary care attendances and complications.Results
Twenty-one studies were included (15 case series, 2 cohort studies, 1 case control, 3 RCTs). Five studies described medical treatment (nifedipine, cisapride, opiates); seven studies described endoscopic or surgical intervention. Early presentation of PCS (<3 years post-cholecystectomy) was more likely to be gastric in origin, and later presentations were found to be more likely due to retained stones. Sphincter of Oddi dysfunction (SOD) accounted for a third of cases in an unselected population with PCS.Conclusions
Causes of post cholecystectomy syndrome are varied and many can be attributed to extra-biliary causes, which may be present prior to surgery. Early symptoms may warrant early upper gastrointestinal endoscopy. Delayed presentations are more likely to be associated with retained biliary stones. A large proportion of patients will have no cause identified. Treatment options for this latter group are limited. 相似文献55.
Pathogenesis of myasthenia gravis 总被引:7,自引:0,他引:7
A. Marx A. Wilisch A. Schultz S. Gattenlöhner R. Nenninger H. K. Müller-Hermelink 《Virchows Archiv : an international journal of pathology》1997,430(5):355-364
Various studies over the last 25 years in Man and animal models have revealed many steps in the pathogenesis of myasthenia
gravis (MG) which is now considered the classical organ specific, autoantibody mediated and T cell dependent human autoimmune
disease. Though not a disease entity, MG is associated with pathological alterations of the thymus in about 80% of cases.
These are described here with reference to distinct models of autoimmunization against the acetylcholine receptor (AChR).
In MG with thymitis, intrathymic production of AChR-specific autoantibodies is the result of a classical antigen-driven immune
reaction that occurs completely inside the thymus and probably involves AChR on myoid cells as the triggering (myasthenogenic)
antigen. Genetic factors contribute essentially to the pathogenesis of this form of MG. In thymoma-associated MG genetic factors
are probably of marginal significance. Neither intratumour autoantibody production nor T cell activation seem to occur and
the AChR is not the myasthenogenic antigen. Instead, abnormal neurofilaments that share epitopes with the AChR and other autoantigen
targets in paraneoplastic MG are expressed in thymomas and may trigger autoantigen-specific, non-tolerogenic T cell selection
by molecular mimicry. These data support the hypothesis that initial steps in the pathogenesis of most MG cases take place
within abnormal thymic microenvironments, be they inflammatory or neoplastic. Where these initial steps occur in MG cases
without thymic pathology is not known. Likewise, the factors involved in the initial triggering of MG remain enigmatic in
all MG subtypes.
Received: 16 September 1996 / Accepted: 28 October 1996 相似文献
56.
Parental α 1-antitrypsin (PI) types and meiotic nondisjunction in the aetiology of Down syndrome 总被引:2,自引:0,他引:2
In 100 children with Down syndrome (DS), the parental origin of the supernumery chromosome 21 was investigated. In 76 out of the 100 cases the polymorphic regions were informative, i.e. the nondisjunction could be traced. Assessment of the alpha 1-antitrypsin/alpha 1-protease inhibitor (PI) types in these DS children revealed a significantly higher value of non-M PI variants (P less than 0.05). In their fathers the non-M PI variants were not increased, not even in those in whom nondisjunction had taken place. A clearly significantly higher value (P less than 0.001) of non-M PI variants was found in their mothers, particularly when only the MS and MZ types which are recognised as deficiency variants were considered. Most striking, however, is the almost 5-fold increased frequency of MS and MZ types found in mothers where the nondisjunction had occurred during the first meiotic division. This would suggest that PI deficiency interferes with some process leading to non-disjunction. If these findings are confirmed, application of Bayes' theorem enables us to estimate the risk for MZ and MS heterozygous women to have a DS child: this would be 3- to 4- fold higher than for MM homozygous women. This would be of interest for genetic counselling and enhance the benefits of prenatal diagnosis programmes. 相似文献
57.
58.
Pneumonia remains the major cause of childhood morbidity and mortality globally, despite improved preventative strategies. Increasing evidence also links early life pneumonia with the development of chronic non-communicable respiratory diseases into childhood and adulthood. The Drakenstein Child Health Study is a unique, multidisciplinary, South African birth cohort, investigating the incidence, risk factors, aetiology and long term impact of early life pneumonia on child health. The study provides novel data showing a high incidence of pneumonia despite excellent immunisation coverage; that pneumonia is due to multiple pathogens; that dysbiosis of the nasopharyngeal flora precedes and predisposes to pneumonia; and that early life pneumonia results in reduced lung function. 相似文献
59.
R. Dyrhovden R.M. Nygaard R. Patel E. Ulvestad Ø. Kommedal 《Clinical microbiology and infection》2019,21(8):981-986
ObjectivesThe view of pleural empyema as a complication of bacterial pneumonia is changing because many patients lack evidence of underlying pneumonia. To further our understanding of pathophysiological mechanisms, we conducted in-depth microbiological characterization of empyemas in clinically well-characterized patients and investigated observed microbial parallels between pleural empyemas and brain abscesses.MethodsCulture-positive and/or 16S rRNA gene PCR-positive pleural fluids were analysed using massive parallel sequencing of the 16S rRNA and rpoB genes. Clinical details were evaluated by medical record review. Comparative analysis with brain abscesses was performed using metagenomic data from a national Norwegian study.ResultsSixty-four individuals with empyema were included. Thirty-seven had a well-defined microbial aetiology, while 27, all of whom had community-acquired infections, did not. In the latter subset, Fusobacterium nucleatum and/or Streptococcus intermedius was detected in 26 patients, of which 18 had additional facultative and/or anaerobic species in various combinations. For this group, there was 65.5% species overlap with brain abscesses; predisposing factors included dental infection, minor chest trauma, chronic obstructive pulmonary disease, drug abuse, alcoholism and diabetes mellitus. Altogether, massive parallel sequencing yielded 385 bacterial detections, whereas culture detected 38 (10%) and 16S rRNA gene PCR/Sanger-based sequencing detected 87 (23%).ConclusionsA subgroup of pleural empyema appears to be caused by a set of bacteria not normally considered to be involved in pneumonia. Such empyemas appear to have a similar microbial profile to oral/sinus-derived brain abscesses, supporting spread from the oral cavity, potentially haematogenously. We suggest reserving the term ‘primary empyema’ for these infections. 相似文献
60.
M. Weber J. Gubler H. Fahrer M. Crippa R. Kissling N. Boos H. Gerber 《Clinical rheumatology》1999,18(5):417-421
Three cases of spondylodiscitis caused by viridans streptococci were observed within the course of 1 month. Although streptococci
have been reported as the third most frequent cause of spondylodiscitis after staphylococci and gram-negative bacteria, α-haemolytic
streptococci are rarely seen. The three patients presented with symptoms of low back pain; they felt well and did not have
a fever or chills. Laboratory examinations revealed inflammation. Further examinations such as scintigraphy, computed tomography
or magnetic resonance imaging were done. Bacteriological diagnosis was established by blood cultures in two cases and by needle
biopsy of the disco-vertebral space in one. In one patient endocarditis was also documented. Because the prevalence of endocarditis
was found to be higher in our cases of spondylodiscitis due to Streptococcus viridans than for other bacteria, the exclusion of this diagnosis must be pursued aggressively. These observations lead us to question
if the spectrum of bacteria causing spondylodiscitis is undergoing a change.
Received: 15 October 1998 / Accepted: 12 April 1999 相似文献