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61.
Percutaneous biopsy in lung cancer   总被引:9,自引:0,他引:9  
This paper presents current indications, contraindications, technical aspects, complications and yield of diagnosis of percutaneous lung biopsy in the setting of lung cancer. Percutaneous lung biopsy should be performed each time that the therapeutic strategy can be significantly influenced, when the procedure is technically feasible and to patients for which the benefits outweigh the risks, that are pneumothorax and pulmonary haemorrhage. Factors identified as potentially favouring post-biopsy pneumothorax are numerous whereas the use of a needle size larger than 18 gauge is the major risk factor of bleeding. Although a coaxial system is highly suitable in any case, two categories of needles can be used; those providing aspiration and those for core biopsies. Both offer similar yields for the diagnosis of malignancy, but core biopsies are more efficient for the specific diagnosis of benignity and lymphoma. Technical improvements of guidance, needle design and pathological techniques may contribute to lower the size limit of the nodule to be biopsied, to decrease the complication rate and their severity and to increase the yield of diagnosis.  相似文献   
62.
The aim of this study was to investigate the work-rate of substitutes in professional soccer. A computerised player tracking system was used to assess the work-rates of second-half substitutes (11 midfielders and 14 forwards) in a French Ligue 1 club. Total distance, distance covered in five categories of movement intensity and recovery time between high-intensity efforts were evaluated. First- and second-half work-rates of the replaced players were compared. The performance of substitutes was compared to that of the players they replaced, to team-mates in the same position who remained on the pitch after the substitution and in relation to their habitual performances when starting games. No differences in work-rate between first- and second-halves were observed in all players who were substituted. In the second-half, a non-significant trend was observed in midfield substitutes who covered greater distances than the player they replaced whereas no differences were observed in forwards. Midfield substitutes covered a greater overall distance and distance at high-intensities (p < 0.01) and had a lower recovery time between high-intensity efforts (p < 0.01) compared to other midfield team-mates who remained on the pitch. Forwards covered less distance (p < 0.01) in their first 10-min as a substitute compared to their habitual work-rate profile in the opening 10-min when starting matches while this finding was not observed in midfielders. These findings suggest that compared to midfield substitutes, forward substitutes did not utilise their full physical potential. Further investigation is warranted into the reasons behind this finding in order to optimise the work-rate contributions of forward substitutes.  相似文献   
63.
ObjectiveTo evaluate the benefits, regarding prevention and clinical pregnancy rates, of embryos cryopreservation in patients at high risk of ovarian hyper-stimulation.Patients and methodsRetrospective study with 66 patients divided into two groups. Group 1 (n = 24), cryopreservation of all the embryos due to high risk of OHSS. Group 2 (n = 42), fresh embryo transfer despite of ovarian hyper-response (E2 > 4000/mL, hCG day). We performed a comparative analysis for group 1 and 2 regarding implantation, pregnancy, live birth and spontaneous abortion rates.ResultsNo case of OHSS was observed in group 1 and 40.5 % in group 2. Fresh embryo transfer in group 2 gave the following results: 12.9 % implantation rate, 21.4 % pregnancy rate per transfer and 22.2 % spontaneous abortion. Identical implantation and pregnancy rates after frozen ET cycles were observed in both groups. Whereas live birth rates were significantly better in group 1 (15.4 % vs. 67 %, P = 0.04) with a significant lower rate of spontaneous abortion (27 % vs. 11.4 %, P < 0,01).Discussion and conclusionThe negative impact of hyperestrogenic state seems to be limited to endometrial receptivity with no effect on oocyte or embryo quality. In situation of ovarian hyper-response, cryopreservation of all embryos with subsequent transfer of thawed embryos is an efficient strategy to avoid OHSS without decreasing pregnancy and live birth rates.  相似文献   
64.
Erdheim-Chester disease (ECD) is a rare, non-Langerhans form of histiocytosis of unknown etiology that affects multiple organs. We report 6 cases of ECD with neurological involvement and neuroradiological abnormalities on brain MRI. A literature review revealed 60 other cases of ECD with neurological involvement. We therefore analyzed 66 ECD patients with neurological involvement. Cerebellar and pyramidal syndromes were the most frequent clinical manifestations (41% and 45% of cases), but seizures, headaches, neuropsychiatric or cognitive troubles, sensory disturbances, cranial nerve paralysis or asymptomatic lesions were also reported. Neurological manifestations were always associated with other organ involvement, especially of bones (at least 86%) and diabetes insipidus (47%). Neurological involvement was responsible for severe functional handicaps in almost all patients and was responsible for the death of 6 of the 66 patients (9%). Neuroradiological findings could be separated into three patterns: the infiltrative pattern (44%), with widespread lesions, nodules or intracerebral masses, the meningeal pattern (37%), with either thickening of the dura mater or meningioma-like tumors, and the composite pattern (19%), with both infiltrative and meningeal lesions. Received in revised form: 21 October 2005  相似文献   
65.
Strong evidence shows that mitochondrial dysfunction is involved in amyotrophic lateral sclerosis (ALS), but despite the fact that mitochondria play a central role in excitotoxicity, oxidative stress and apoptosis, the intimate underlying mechanism linking mitochondrial defects to motor neuron degeneration in ALS still remains elusive. Morphological and functional abnormalities occur in mitochondria in ALS patients and related animal models, although their exact nature and extent are controversial. Recent studies postulate that the mislocalization in mitochondria of mutant forms of copper-zinc superoxide dismutase (SOD1), the only well-documented cause of familial ALS, may account for the toxic gain of function of the enzyme, and hence induce motor neuron death. On the other hand, mitochondrial dysfunction in ALS does not seem to be restricted only to motor neurons as it is also present in other tissues, particularly the skeletal muscle. The presence of this 'systemic' defect in energy metabolism associated with the disease is supported in skeletal muscle tissue by impaired mitochondrial respiration and overexpression of uncoupling protein 3. In addition, the lifespan of transgenic mutant SOD1 mice is increased by a highly energetic diet compensating both the metabolic defect and the motorneuronal function. In this review, we will focus on the mitochondrial dysfunction linked to ALS and the cause-and-effect relationships between mitochondria and the pathological mechanisms thought to be involved in the disease.  相似文献   
66.
67.
Abstract

Background: Thought content and its impact on sustained attention in individuals with attention deficit hyperactivity disorder (ADHD) are topics of growing interest in literature.

Objective: We hypothesised that subclinical obsessive thoughts may be correlated with attention lapses in individuals with ADHD.

Method: Thirty children diagnosed with ADHD participated in the study and their level of subclinical obsessive thoughts, attention, and executive function were measured using Children Yale-Brown Obsessive Scale and Conners’ Continuous Performance Test II.

Results: No significant correlation between sustained attention impairment and the level of obsessive thoughts in patients with ADHD was found. Nevertheless, patients with ADHD with subclinical obsessive thoughts showed more commission errors than those without (W?=?51.5; p?=?0.02).

Conclusion: The nature of thought content in individuals with ADHD should be linked to executive dysfunction rather than attentional impairment. This could be of importance in the therapeutic strategy choice, addressing the importance of executive function remediation in the specific context of subclinical obsessive thoughts.
  • Key points
  • ?Patients with ADHD, without OCD or ASD comorbidity, still present subclinical obsessive thoughts (36% of our sample). ??Subclinical obsessive thoughts could be a part of thought content in patients with ADHD.

  • ???Subclinical obsessive thoughts as measured by the CPT-II are not correlated with attention function in patients with ADHD.

  • ???ADHD patients with subclinical obsessive symptoms present more impairment in response inhibition than the ones without.

  • ???Results on subclinical obsessive thoughts are similar to those on another type of thought content called ‘mind wandering’.

  • ???A clinical improvement strategy for patients with ADHD could be using executive function remediation rather than classical attention function remediation, according to both to our and previous results.

  相似文献   
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