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61.
62.
Chromosome studies of peripheral blood lymphocytes in 25 subjects who had recovered from benzene hemopathy, in four subjects with bone marrow toxicity from benzene, and in three subjects who had recovered from acute benzene poisoning revealed significantly increased rates of “unstable” and “stable” chromosome aberrations which, In most cases, were still present several years after cessation of exposure to the toxic agent and recovery from the poisoning. The follow-up cytogenetic studies showed a tendency toward a decrease in unstable chromosome changes and, generally, a persistence or an increase in stable changes. Bn some cases there was evidence of abnormal clone formation in peripheral blood lymphocytes. Chromosomes of the G group seemed to be involved in stable changes with a frequency higher than expected.  相似文献   
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Antegrade scrotal sclerotherapy is a simple and easy technique for the treatment of varicocele.The success rate varies between87%and95%,The initlal reflux grade and the number of collateral vessels of the spermatic vein are the most important factors to predict the outcome of the technique.The postoperative complica-tion rate is about7%and the common ones are scrotal hematoma and epididymo-orchitis of slight severity.Testicular athrophy is a rare event(0.6%).This technique offers a considerable cost eduction compared to other therapeutic optione currently available for varicocele.  相似文献   
66.
Verocytotoxin-producing Escherichia coli(VTEC) infections cause most cases of hemolytic uremic syndrome (HUS); 10-30% of patients, however, are negative for VTEC infection. The etiology of HUS in VTEC-negative cases remains poorly understood. Before the association between VTEC infection and HUS was recognized, sporadic cases of HUS with enterovirus infection were reported in the literature. Since May 1988, most cases of HUS in Italy have been reported to the Italian surveillance system, and in 73% of these, evidence of VTEC infection was demonstrated. The aim of this study was to determine whether the frequency of enteroviral infections was different in the acute phase of VTEC-positive and VTEC-negative HUS. Eighty-nine patients were investigated for enteroviral infection, of whom 58 were VTEC positive and 31 VTEC negative. Two serum samples from each patient were examined for seroconversion to enterovirus (coxsackie, echovirus, and picornavirus) by a complement fixation test. Serological evidence of acute infection with non-polio enterovirus was found in 33 patients (37%) [20/58 (34.5%) VTEC positive and 13/31 (41.9%) VTEC negative]. There was no statistically significant difference between the two groups. These results demonstrate that there are no significant differences for enteroviral infection in VTEC-positive and VTEC-negative patients and, therefore, enteroviral infections should not be considered a cause of HUS in VTEC-negative children.  相似文献   
67.

Objective

Frey's syndrome is a frequent sequela of parotidectomy, causing facial sweating and flushing because of gustatory stimuli. Although botulinum toxin type A has become first-line therapy for Frey's syndrome, some patients become resistant. In this study, we investigated whether another serotype, botulinum toxin type B, might be an effective alternative.

Study Design

Case series with planned data collection.

Setting

Otolaryngology department in a university hospital.

Subjects and Methods

Seven patients aged 30 to 68 years, with severe Frey's syndrome, underwent the Minor test and had 80 U of botulinum toxin type B per cm2 (mean total dose, 2354 U) injected intracutaneously in the mapped area of gustatory sweating. All patients were followed up for 12 months.

Results

One month after treatment, six of the seven patients reported that gustatory sweating and flushing had resolved, and, in the remaining patient, these symptoms had decreased. The Minor test confirmed a significant improvement. The subjective benefits remained stable for six months in four patients and for nine months in the remaining three patients; 12 months after treatment, all patients still reported some improvement.

Conclusion

Botulinum toxin type B afforded symptomatic relief in a small sample of patients with Frey's syndrome and might be considered a potential alternative to botulinum toxin type A.  相似文献   
68.
Conditional mouse knock-outs provide an informative approach to drug target validation where no pharmacological blockers exist or global knock-outs are lethal. Here, we used the Cre-loxP system to delete BDNF in most nociceptive sensory neurons. Conditional null animals were healthy with no sensory neuron loss. However, pain-related behavior was substantially altered. Baseline thermal thresholds were reduced. Carrageenan-induced thermal hyperalgesia was inhibited. Formalin-induced pain behavior was attenuated in the second phase, and this correlated with abolition of NMDA receptor NR1 Ser896/897 phosphorylation and ERK1 and ERK2 activation in the dorsal horn; AMPA receptor phosphorylation (GluR1/Ser831) was unaffected. NGF-induced thermal hyperalgesia was halved, and mechanical secondary hyperalgesia caused by intramuscular NGF was abolished. By contrast, neuropathic pain behavior developed normally. Nociceptor-derived BDNF thus plays an important role in regulating inflammatory pain thresholds and secondary hyperalgesia, but BDNF released only from nociceptors plays no role in the development of neuropathic pain.  相似文献   
69.
Negative pressure wound therapy (NPWT) is becoming routine for the preparation of wounds prior to grafting for wound closure. We have been using both foam- and gauze-based NPWT to prepare wounds for closure prior to skin grafting and have obtained similar proportions of closed wounds; 7/7 for wounds treated with gauze-based NPWT and 11/11 for wounds treated with foam-based NPWT. In our follow-up consultations we observed that skin grafts on the foam-treated patients were less pliable than those on the gauze-treated patients. To assess what the mechanism of this effect might be, we compared the specific details of the treatments of both 11 foam and 7 gauze patients, including depth, location, patients' age and co-morbidity; biopsies of granulation and scar tissue were taken and stained with haematoxylin-eosin and by Masson's trichrome staining and conducted ultrasound analysis of the closed wounds, to see if there were features which explained those effects. All foam patients were treated at -125 mm Hg for an average of 25·9 days before skin grafts were applied. All gauze patients were treated at -80 mm Hg for an average of 24·7 days before skin grafts were applied. Biopsies of granulation tissue prior to skin grafting from five foam and four gauze-based NPWT patients did not reveal any obvious histological differences between the treatments. Ultrasound analysis of the skin-grafted wounds showed an average depth of scar tissue of 18 mm in the wound beds of the foam-treated wounds and 7 mm in the gauze-treated ones. Biopsies taken on the scar tissue after treatment with the gauze showed a minor tissue thickness and disorganisation and less sclerotic components. The findings of this preliminary analysis suggest that foam-based NPWT may induce a thicker layer of scar tissue beneath skin grafts than gauze-based NPWT which might explain a reduced pliability of the reconstructed bed. At present it is unclear which mechanism might be responsible for the difference in pressure (-125 versus -80 mm Hg), either the length of the time taken to reconstruct the wound bed or the intrinsic nature of the foam or gauze on the tissue surface. Prospective studies are necessary to investigate whether these preliminary observations are confirmed and to investigate what the mechanism might be.  相似文献   
70.
The objective of this study was to evaluate a percutaneous extravascular closure device (StarClose, Abbott Vascular, Redwood City, CA) after brachial endovascular approach. From 2004 to 2006, 29 patients received StarClose for brachial closure. Primary endpoints were successful deployment and absence of procedure-related morbidity, secondary endpoints were brachial artery patency on duplex and absence of late (> 30 days) complications. The device was successfully deployed in all patients. In two patients (6.8%) local complications occurred: one patient developed a large hematoma successfully treated with prolonged compression and a second patient presented with brachial artery occlusion requiring operative intervention. After a mean follow-up of 7.5+/-7.2 months, all patients had a palpable brachial/radial pulse; none had signs of infection, distal embolization or neurological deficits. On ultrasound b-mode imaging, the clip was visible as a 4 mm echolucent area at the outer anterior wall of the artery. Based on the peak systolic velocity ratios between the site of StarClose and proximal brachial artery (mean 1.08+/-0.2), none of the studied patients had a significant stenosis at the site of closure. StarClose is safe and effective in providing hemostasis following interventional procedures through the brachial artery; further advantages include patients comfort and early discharge.  相似文献   
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