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1.
OBJECTIVE: To verify whether immunohistochemistry might be useful in the distinction between a true laterocervical metastasis of an undetected thyroid carcinoma and a primary tumor outside the gland. DESIGN: Galectin-3, cytokeratin 19, and HBME-1 were assessed in six cases (group A) of laterocervical masses harboring papillary thyroid carcinoma (PTC) but without a thyroid tumor, and in eight cases (group B) showing PTC both in the thyroid and in the laterocervical masses. In both groups, normal-looking follicles adjacent to the laterocervical neoplasia were present. MAIN OUTCOME: We found that the apparently normal follicles in group A were negative for all the antibodies, while group B showed strong and diffuse positive immunostaining. The neoplastic areas were always positive for all the antibodies in both groups. CONCLUSION: Even if immunohistochemical patterns of residual follicles of group B are very well differentiated that they resemble normal thyroid parenchyma, they may well be metastatic carcinomas. On the contrary, the presence of morphologically and immunohistochemically normal-looking follicles in group A, with no intrathyroid tumor, suggests that the primary PTC might possibly develop in the ectopic thyroid tissue. In cases showing morphologically and immunohistochemically normal-looking follicles in laterocervical masses, these findings might lead to a reduction of the overdiagnosis of metastatic disease of an undetected carcinoma.  相似文献   
2.
OBJECTIVE: The effects of major lung resections on cardiac function in the medium and long term have not been thoroughly evaluated. We have studied right heart function with serial Doppler echocardiography in patients undergoing lobectomy and pneumonectomy during 4 years of follow-up after surgery. METHODS: Thirty-six patients undergoing lobectomy and 15 receiving pneumonectomy were evaluated with one- and two-dimensional Doppler standard transthoracic echocardiography before surgery and 1 week, 3 months, 6 months, 1 year, and 4 years postoperatively. We have studied the right midventricular diastolic diameter (RVDD), the right ventricle free wall thickness, the tricuspid valve insufficiency (TVI) and regurgitation jet (TRJ), and the pulmonary artery systolic pressure (PASP). RESULTS: None of the patients died within the first postoperative year. After lobectomy there were no significant modifications of any variable at any time. RVDD progressively increased after pneumonectomy (26.5+/-2.2mm preoperatively vs 34.3+/-7.6 at 4 years; p<0.001). Four years after surgery all patients undergoing pneumonectomy had moderate TVI while only 55% of patients receiving lobectomy showed it (low grade in 50% and moderate in 5%). In this group of patients PASP increased from 26.1+/-2.6 mmHg preoperatively to 34.3+/-7.6 mmHg at 4 years (p<0.00001). CONCLUSIONS: Right ventricle modifications are clearly evident after pneumonectomy and even if they do not show a clear clinical impact they should not be neglected.  相似文献   
3.
The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine.  相似文献   
4.
The increased use of Ultrasonography (US) has led to increased detection of simple hepatic cysts. For symptomatic cysts treatment is necessary. Until some years ago surgery was the only therapy. We have treated a large number of patients with Percutaneous Alcohol Sclerotherapy (PAS) and evaluated retrospectively the efficacy of this approach.Data on 21 patients with symptomatic simple hepatic cysts were reviewed retrospectively. Cysts had a mean diameter of 9 cm (range: 7–15 cm). PAS was always performed under local anesthesia and US guidance. 25% of the volume was replaced with 95% ethanol and then completely aspirated after 20–30 minutes.No complications or deaths occurred. In all patients symptoms disappeared after treatment. In 15 out of 21 cases there was no evidence of residual cyst on US, computed tomography (CT) or magnetic resonance (MRI). In 6 patients with shorter follow-up, cysts showed a mean reduction in diameter of 50%. The mean follow-up was 18 months (range 6–60 months).We conclude that PAS is easy with low risk for the patients and with good long-term results; it should therefore become the procedure of choice for simple hepatic cysts.  相似文献   
5.
The paper report the case of a patient brought to the Authors' attention suffering from megaesophageal cardial achalasia who had already undergone gastroduodenal resection according to BII. It was considered worthwhile to report this case due to the problems which arose concerning the choice of a thoracic rather than abdominal route owing to the impossibility of associating cardiomyotomy with anti-reflux plastica surgery because of the reduced dimensions of the stomach.  相似文献   
6.
Prostatic endoscopic resection (TURP) is a reference method in the treatment of prostatic obstruction. In the past decades, the method used a monopolar resectoscope. In the last years, various technologies have been studied to improve the efficacy of endoscopic resection. As per our experience, we have thence ascertained the variations of the hematic crasis and of the mictional asset in TURP patients treated with bipolar knives. 20 patients underwent bipolar plasmakinetic resection of the prostate. Their age ranged between 58 yrs and 82 yrs (av.: 70.2 yrs), the adenoma volume, checked with TR ultrasound scanning, was between 33 and 44 cc (av.: 37.6), the Qmax was between 6.4 and 9.0 mL/min (av.: 7.42 mL/min). A 24Ch resectoscope and spinal anesthesia were used. Bleeding during resection was never relevant; therefore resection never had to be stopped. After about 36 hours from surgery, the patients' sanguification was checked again: a 6.53% reduction of the number of erythrocytes, compared to pre-surgery data, was observed, together with a 6.73% decrease of hemoglobin concentration, and a 6.3% decrease of hematocrit. Continuous irrigation was suspended during the first day, catheter was removed on the 48th hour in 15 cases, and on the 72nd in 5 cases: the patients were discharged on day 3 in 16 cases, and on day 4 in 4 cases. A flux evaluation was performed after 3 months, which showed a Qmax between 16.6 and 24 mL/min (av.: 19.11), with a significant increase in the maximum flow rate. The use of the new technologies in prostatic endoscopic resection has allowed us to improve the efficacy of such a method. Above all, the use of a bipolar electrosurgical knife enables us to associate a basal hemostasis with the resection of the prostatic tissue. Thus, the hematic loss is low, as we have been able to ascertain also in our own experience. This gave us the possibility to quickly stop continuous irrigation and to early remove the catheter. This way, hospitalization was sensibly reduced (av. 76.8 hours). The maximum flow rate, in the short term, has been good. We have been able, in our experience, to assess that this technology represents a useful guarantee to improve the results of prostatic endoscopic resection.  相似文献   
7.
The authors report their experience with the diagnosis and surgical correction of varicoceles in 20 patients. They stress the usefulness of the Doppler Ultrasound for the diagnosis of subclinical varicocele.  相似文献   
8.
Calcineurin (CaN) is a Ca2+- and calmodulin-dependent protein phosphatase (PP2B) that, in yeast, is an integral intermediate of a salt-stress signal transduction pathway that effects NaCl tolerance through the regulation of Na+ influx and efflux. A truncated form of the catalytic subunit and the regulatory subunit of yeast CaN were coexpressed in transgenic tobacco plants to reconstitute a constitutively activated phosphatase in vivo. Several different transgenic lines that expressed activated CaN also exhibited substantial NaCl tolerance, and this trait was linked to the genetic inheritance of the CaN transgenes. Enhanced capacity of plants expressing CaN to survive NaCl shock was similar when evaluation was conducted on seedlings in tissue culture raft vessels or plants in hydroponic culture that were transpiring actively. Root growth was less perturbed than shoot growth by NaCl in plants expressing CaN. Also, NaCl stress survival of control shoots was enhanced substantially when grafted onto roots of plants expressing CaN, further implicating a significant function of the phosphatase in the preservation of root integrity during salt shock. Together, these results indicate that in plants, like in yeast, a Ca2+- and calmodulin-dependent CaN signal pathway regulates determinants of salt tolerance required for stress adaptation. Furthermore, modulation of this pathway by expression of an activated regulatory intermediate substantially enhanced salt tolerance.  相似文献   
9.
Summary Monoclonal antibodies raised against the separated hemagglutinin subunits (HA1 and HA2) of influenza A/Vic/3/75 (H3N2) virus were tested against a large panel of human and avian strains. The epitopes recognized by most antibodies were conserved among subtype H3 viruses, but reactivity of some antibodies with members of other subtypes was also observed. Particularly, the H4 virus reacted with most antibodies directed against the HA2 subunit. These results are discussed in terms of sequence similarities between subtypes and application of these antibodies as subtyping reagents.  相似文献   
10.
Familial incontinentia pigmenti (IP) is a rare X-linked dominant disorder that affects ectodermal tissues. Over 90% of IP carrier females have a recurrent genomic deletion of exons 4-10 of the NEMO (IKBKG-IKKgamma) gene, which encodes a regulatory component of the IkB kinase complex, required to activate the NF-kB pathway. In IP, mutations in NEMOlead to the complete loss of NF-kB activation creating a susceptibility to cellular apoptosis in response to TNF-alpha. This condition is lethal for males during embryogenesis while females, who are mosaic as a result of X-inactivation, can survive. Recently, a second nonfunctional copy of the gene, DeltaNEMO, was identified, opposite in direction to NEMO in a 35.5-kb duplicated sequence tract. PCR-based detection of the NEMO deletion is diagnostic for IP disease. However, we present instances in which ex 4-10 DeltaNEMO pseudogene deletion occurs in unaffected parents of two females with clinically characteristic IP. These were missed by the currently standard PCR-based method, but can be easily discriminated by a new PCR-based test reported here that permits unambiguous molecular diagnosis and proper familial genetic counseling for IP.  相似文献   
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