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排序方式: 共有291条查询结果,搜索用时 31 毫秒
91.
John M van Ochten Marinka CE Mos Nienke van Putte-Katier Edwin HG Oei Patrick JE Bindels Sita MA Bierma-Zeinstra Marienke van Middelkoop 《The British journal of general practice》2014,64(626):e545-e553
Background
Persistent complaints are very common after a lateral ankle sprain.Aim
To investigate possible associations between structural abnormalities on radiography and MRI, and persistent complaints after a lateral ankle sprain.Design and setting
Observational case control study on primary care patients in general practice.Method
Patients were selected who had visited their GP with an ankle sprain 6–12 months before the study; all received a standardised questionnaire, underwent a physical examination, and radiography and MRI of the ankle. Patients with and without persistent complaints were compared regarding structural abnormalities found on radiography and MRI; analyses were adjusted for age, sex, and body mass index.Results
Of the 206 included patients, 98 had persistent complaints and 108 did not. No significant differences were found in structural abnormalities between patients with and without persistent complaints. In both groups, however, many structural abnormalities were found on radiography in the talocrural joint (47.2% osteophytes and 45.1% osteoarthritis) and the talonavicular joint (36.5% sclerosis). On MRI, a high prevalence was found of bone oedema (33.8%) and osteophytes (39.5) in the talocrural joint; osteophytes (54.4%), sclerosis (47.2%), and osteoarthritis (55.4%, Kellgren and Lawrence grade >1) in the talonavicular joint, as well as ligament damage (16.4%) in the anterior talofibular ligament.Conclusion
The prevalence of structural abnormalities is high on radiography and MRI in patients presenting in general practice with a previous ankle sprain. There is no difference in structural abnormalities, however, between patients with and without persistent complaints. Using imaging only will not lead to diagnosis of the explicit reason for the persistent complaint. 相似文献92.
93.
Dorsal onlay augmentation urethroplasty with small intestinal submucosa: Modified Barbagli technique for strictures of the bulbar urethra 总被引:1,自引:0,他引:1
IVO I DONKOV AZMAT BASHIR CHAVDAR HG ELENKOV PETAR K PANCHEV 《International journal of urology》2006,13(11):1415-1417
AIM: To present the results from one clinic's experience of using small intestinal submucosa (SIS) in augmentation urethroplasty for management of strictures of the bulbar urethra. METHODS: Urethral surgery was performed in nine men with strictures 4-6 cm. All of the patients were evaluated by history, physical examination, retrograde urethrogram, and uroflowmetry. Four layers of SIS were soaked in saline or Ringer's solution for 15 minutes at 37 degrees C, and the inner surface of the patch was gently fenestrated with a thin scalpel. The patch was spread-fixed onto the tunica albuginea. The mucosa was sutured to the submucosal graft first at 2-3 mm inwards from the SIS margins, then the spongiosum tissue was attached to the margins with interrupted absorbable sutures. RESULTS: Of the nine patients who underwent augmentation urethroplasty using SIS, only one had re-stricture at 6 months due to urethral infection. At 18 months after the surgery the uroflowmetry of the other eight patients was 20-21 mL/s. In terms of complications, six patients reported having post-micturition dribbling, and seven patients reported lack of morning erections for 35-69 days after surgery. CONCLUSIONS: Using SIS is a safe procedure; however, long-term follow-up is needed to substantiate the good short-term results. 相似文献
94.
Comparative evaluation of iohexol and inulin clearance for glomerular filtration rate determinations 总被引:2,自引:0,他引:2
We evaluated iohexol as a filtration marker in 150 children. The clearance of iohexol was compared with that of inulin or with a formula clearance. The single-sample clearance of iohexol showed a good correlation with the clearance of inulin ( r = 0.834). The clearance of iohexol correlated well ( r = 0.672) with the formula clearance. The optimal blood sampling time for iohexol clearance determinations appears to be between 120 and 180 min after injection, at least in patients with relatively normal filtration rates. We conclude that iohexol clearance is an accurate method of determining the glomerular filtration rate in clinical practice. 相似文献
95.
Activation of ras proto-oncogenes occurs frequently in vivo in chemically
induced rodent tumours, including rat hepatomas induced by aflatoxin B1.
This study examines the in vitro activation of a human ras gene by this
mycotoxin. A plasmid containing the human Ha-ras proto- oncogene, together
with a neomycin resistance gene (pECneo), was incubated in vitro with a
microsomal system generating aflatoxin B1 8,9- epoxide. Subsequent
transfection of the plasmid into mouse NIH 3T3 fibroblasts, followed by
G418 selection and s.c. injection of surviving cells into immunodeficient
mice demonstrated that the proto-oncogene had acquired transforming
capacity. Although a single tumour resulted from similar treatment of
incubated unconjugated plasmid, no tumours were produced by a secondary
round of transfections using DNA from this tumour. Selective PCR
amplification of the human Ha-ras gene in extracted tumour DNA followed by
sequencing demonstrated the presence of G-->T transversions either at
the first or middle base of codon 12 in tumours resulting from transfection
with the aflatoxin-B1-modified pECneo plasmid, but this was not detected in
the single tumour resulting from transfection with the unmodified plasmid.
Thus, although a mutation in the Ha-ras gene has not been reported for
human primary hepatomas occurring in aflatoxin-exposed populations,
metabolically activated aflatoxin B1 is capable of mutating this
proto-oncogene to its oncogenic form in vitro. No mutations were observed
in codon 61. It appears that, in contrast to the frequently reported
G-->T transversions in codon 249 of the p53 gene in primary hepatomas in
aflatoxin-exposed humans, the failure to detect Ha-ras mutations in these
tumours is not due to an inability of aflatoxin B1 to activate this
proto-oncogene. The G-->T transversions observed in this study contrast
with the most frequent aflatoxin B1 in vivo induced mutations, G-->A
transitions in the rat Ki-ras gene. Possible mechanisms for these
differences are discussed.
相似文献
96.
97.
98.
Evidence for naturally occurring recombination in the gene encoding the major outer membrane protein of lymphogranuloma venereum isolates of Chlamydia trachomatis. 总被引:1,自引:0,他引:1 下载免费PDF全文
L J Hayes P Yearsley J D Treharne R A Ballard G H Fehler M E Ward 《Infection and immunity》1994,62(12):5659-5663
The nucleotide sequence of the major outer membrane protein gene (omp1) was determined for three geographically distinct lymphogranuloma venereum isolates which were serologically untypeable. The three omp1 sequences were hybrids of serovars L1 and L2, containing a putative DNA recombination site in variable segment 2. Efforts to manipulate the chlamydial genome in vitro by recombination should be intensified. 相似文献
99.
Epstein-Barr virus-associated hemophagocytic syndrome: virological and immunopathological studies 总被引:5,自引:0,他引:5
The virus-associated hemophagocytic syndrome (VAHS) is a disorder characterized by a benign, generalized histiocytic proliferation, with marked hemophagocytosis associated with systemic viral infections. We have studied the virological and immunopathological events occurring in two children experiencing Epstein-Barr VAHS. Neither of the patients had an underlying immunodeficiency and both recovered from their disease and are completely well one year after follow-up. In each patient, evidence for primary Epstein-Barr virus (EBV) infection was documented with a typical humoral immune response, including IgM antibody directed against virus capsid antigen. EBV was demonstrated in lymphoreticular tissues by electron microscopy and molecular hybridization studies. Permissive EBV infection was suggested by the finding of mature virus particles and linear viral DNA in lymphoreticular tissues. Immunopathological studies demonstrated complete effacement of lymph node architecture by a marked proliferation of immunoblasts in patient 1 and infiltration and effacement of the lymph node architecture with benign-appearing histiocytes in patient 2. Atypical lymphocytes characteristic of acute EBV infection were notably absent in the peripheral blood of both patients and cytotoxic T cells, which normally lyse EBV-infected B cells, were also absent from the peripheral circulation. Our observations suggest that EBV-induced VAHS may be the result of an increased virus burden in the face of immunoregulatory cell imbalances. 相似文献
100.
Wilms tumor usually occurs as an abdominal mass arising from the renal parenchyma. A case was encountered in which the neoplasm filled the pelvicalyceal system of an 8-year-old boy as a botryoid mass, with minimal parenchymal involvement. The radiologic manifestations, pathologic features, and surgical implications are discussed. 相似文献