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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.
Federico Venuta Susanna Sciomer Claudio Andreetti Marco Anile Tiziano De Giacomo Matilde Rolla Francesco Fedele Giorgio Furio Coloni 《European journal of cardio-thoracic surgery》2007,32(5):787-790
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.
4.
Matilde Valencia-Flores David N. Velázquez-Martínez Julían E. Villarreal 《Psychopharmacology》1990,102(1):136-144
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
5.
J. M. Gloor F. G. Cosio D. J. Rea H. M. Wadei J. L. Winters S. B. Moore S. R. DeGoey D. J. Lager J. P. Grande M. D. Stegall 《American journal of transplantation》2006,6(8):1841-1847
Recent protocols have allowed successful positive crossmatch (+XM) and ABO incompatible (ABOI) kidney transplantation, although their long-term outcome is not clear. To begin to assess this issue we compared protocol biopsies performed 12 months posttransplant in 37 +XM, 24 ABOI and 198 conventional allografts. Although the majority in all three groups had only minimal histologic changes, transplant glomerulopathy (TG) was significantly increased in +XM (22% vs. 13% ABOI vs. 8% conventional, p = 0.015), and correlated with prior humoral rejection (HR) by multivariate analysis (odds ratio 17.5, p < or = 0.0001). Patients with a prior history of HR also had a significant increase in interstitial fibrosis (No HR 54% vs. HR 86%, p = 0.045). In the absence of HR no difference in histologic changes was seen between groups, although all three groups had a demonstrable mild increase in interstitial fibrosis from biopsies performed at the time of transplant. Thus, although HR is associated with an increase in TG, in its absence allograft histology is similar in +XM, ABOI and conventional allografts 1 year posttransplant. 相似文献
6.
David A. Sloan David M. Fleiszer Geoffrey K. Richards David Murray Rea A. Brown 《Journal of surgical oncology》1993,52(2):77-82
Sixty Sprague-Dawley rats were pair-fed one of three nutritionally identical diets. One diet contained “low-fiber” (3.8% crude fiber); the others contained “high fiber” (28.7% crude fiber) composed of either cellulose or lignin. Although both “high fiber” diets had similar stool bulking effects, only the cellulose diet was associated with a reduction in 1,2-dimethylhydrazine (DMH)-induced colon neoplasms. The cellulose diet was also associated with distinct changes in the gut bacterial profile and with a lowered serum cholesterol. © 1993 Wiley-Liss, Inc. 相似文献
7.
Marco Montorsi Guido Torzilli Uberto Fumagalli Stefano Bona Riccardo Rosati Matilde de Simone Vittorio Rovati Franco Mosca Carlo Filice 《HPB surgery》1994,8(2):89-94
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
8.
J P Delalande D Sauvanaud J F Abgrall D Rea J P Egreteau 《Annales fran?aises d'anesthèsie et de rèanimation》1992,11(1):96-99
A case of unexpected cardiac arrest occurring in a 17-year-old male patient is reported. The patient had been admitted after sustaining hand trauma. A first emergency surgical procedure was carried out, followed about three weeks later by another one. No incidents occurred during or after either of these two operations. A third procedure was required about two months after the accident (free toe graft to the thumb of the left hand). The twelve-hour operation was carried out under general anaesthesia and axillary block. The patient was given intravenous heparin (800 IU.h-1) during the procedure on the arm. The patient recovered quickly, and was extubated before his transfer to the recovery room. Fifteen minutes later, the patient's heart rate decreased to 40 b.min-1, followed by a transient cardiorespiratory arrest. The suspicion of pulmonary embolism was confirmed by pulmonary scintigraphy. Thrombolysis was carried out with 2,000 IU.kg-1.h-1 of urokinase for a 72 h period, combined with continuous heparin administration (16 to 36 x 10(3) IU.day-1). The patient recovered after one week. No thrombophlebitis was found for origin of the emboli. Biological investigations carried out both before and after 10 minutes of anoxia revealed a normal fibrinolytic system, but a deficit in protein C (62% antigen, 64% activity). Two years after the episode of pulmonary embolism, the patient, still taking acenocoumarol, remained free from any sequela. Current perioperative management of patients with a known protein C deficit is discussed. 相似文献
9.
Stress signaling through Ca2+/calmodulin-dependent protein phosphatase calcineurin mediates salt adaptation in plants
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Jos M. Pardo Muppala P. Reddy Shuli Yang Albino Maggio Gyung-Hye Huh Tracie Matsumoto Maria A. Coca Matilde Paino-DUrzo Hisashi Koiwa Dae-Jin Yun Abed A. Watad Ray A. Bressan Paul M. Hasegawa 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(16):9681-9686
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
10.