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排序方式: 共有2670条查询结果,搜索用时 15 毫秒
1.
Needle-localized breast biopsy: why do we fail?   总被引:10,自引:0,他引:10  
Jackman  RJ; Marzoni  FA  Jr 《Radiology》1997,204(3):677
  相似文献   
2.
ObjectiveWe examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).MethodThe TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder to 12 weeks of treatment with fluoxetine, cognitive–behavioral therapy, their combination, or pill placebo. The pill placebo group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at weeks 12 (acute phase remitters) and 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.ResultsAt week 36, the estimated remission rates for intention-to-treat cases were as follows: combination, 60%; fluoxetine, 55%; cognitive–behavioral therapy, 64%; and overall, 60%. Paired comparisons reveal that, at week 24, all active treatments converge on remission outcomes. The recovery rate at week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.ConclusionsMost depressed adolescents in all three treatment modalities achieved remission at the end of 9 months of treatment.  相似文献   
3.
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice.  相似文献   
4.
Targeted imaging requires site-specific accumulation of a contrast agent (CA), and the properties of that agent must be selected according to the abundance of the target to obtain a signal above the detection limit of the instrument. However, numerical estimates of receptors per cell are rarely found in the literature. Integrin receptors would be particularly promising targets because of their accessibility from the blood stream and expression on activated neovascular endothelial cells. We systematically estimated the number of integrin receptors of cell lines and primary cells by flow cytometry analysis. Since integrin receptors are heterodimeric molecules, and alpha(v) forms complexes with various beta subunits, the numbers of alpha(v) and beta(3) subunits are therefore dissimilar. The observed values are 3 . 10(3)-1.4 . 10(4)/cell for alpha(v), and 5.3 . 10(2)-1.1 . 10(4)/cell for beta(3). Despite the low number of exposed receptors, we show that up to single-cell MR visualization can be achieved with the use of iron oxide beads complexed with antibodies as CAs.  相似文献   
5.
This retrospective study was made to evaluate the significance of different sports activities that cause variable haemarthrosis with intraarticular lesions of the knee joint. Throughout 1984 to 1988 arthroscopy was performed in 337 patients with acute haemarthrosis. The average time between trauma and arthroscopy was 8 days. ACL rupture was diagnosed in most of these cases. Regarding the different types of sport activities ACL lesions were found in skiers (74%), other winter sports (47%), soccer (53%), tennis and squash (58%), athletics (41%) and indoor (61%). Peripheral meniscus tears associated with haemarthrosis were found in 36% and patellar dislocations in 8%. Isolated MCL ruptures were diagnosed clinically and arthroscopy was not performed in these cases. Throughout 1987 isolated ACL ruptures were fixed by reattachment. This technique was not continued any longer and ACL replacement by patellar tendon as bone-ligament-bone was performed routinely since 1988 in those patients, who required surgery. 56 patients required ACL reconstruction following conservative treatment because of ACL deficiency, when they went back to sports activities. Longitudinal peripheral meniscus tears were fixed by the scape in inside-out technique.  相似文献   
6.
From 1980 to the end of 1988, arthroscopy has been performed on 620 patients with acute hemarthrosis of the knee joint. Of all the intraarticular lesions, 89.4% required surgery. Arthroscopy has changed in the last decade from diagnostic screening to invasive instrumentation for exact operative planing and alternative operative techniques. Hemarthrosis in stable knee joints was caused by minor lesions (7.84%) that did not require surgical procedures. Seventy-three patients had traumatic patellar dislocations--in 33 cases associated with chondral or osteochondral fractures. In 54.8% of the isolated medial retinacular ruptures, simple suture was performed in 14 cases--3 times arthroscopically and 11 times open, combined with lateral retinacular release without redislocation following. Associated chondral fracture indicated surgery in all cases. Isolated meniscus pathology (12.48%) was treated by arthroscopy alone, and refixation of the medial meniscus was carried out using the inside-out technique in 27 cases. Arthroscopic elevation of lateral tibia plateau fracture--indicated by type II fracture according to the AO classification--was performed in 3 cases with excellent results, and was associated with screw fixation and image intensification in 2 patients. Intercondylar eminence fracture is an excellent indication for arthroscopic refixation in the presence of the mono- or two-fragment type of fracture. ACL rupture is the main intra-articular pathology (64.8%) for hemarthrosis of the knee joint, which was diagnosed as an acute injury within the 1st week following trauma (51.04%). Anterior instability can be detected clinically if a careful examination with the Lachman test, combined with the missing end-point and pivot-shift test, is performed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
Syndesmosis transfixation screw   总被引:1,自引:0,他引:1  
Instability of the distal tibia-fibular joint necessitates the implant of a fibular tibial transfixation screw. The screw should be placed 2 cm above the anterior syndesmosis. The angle of insertion is 30 degrees upwards from dorsal in relation to the frontal plane. If tibiofibular stability cannot be maintained following anatomical reconstruction of the fibula the transfixation screw must engage the medial tibial cortex. This is imperative, since the transfixation screw cannot withstand the biomechanical forces during motion and bearing of load if the screw penetrates only three corticals.  相似文献   
8.
Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.  相似文献   
9.
10.
Di Benedetto  P.  Giorgini  T.  Delneri  C.  Biasutti  E. 《Neurological sciences》2006,27(4):s320-s322
Neurological Sciences - Bladder and urethra are innervated peripherally by pelvic parasympathetic, lumbar sympathetic and pudendal nerves; but a complex of brain networks is involved in the...  相似文献   
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