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21.
Atrophic chronic gastritis and Helicobacter pylori infection are considered possible causes of iron deficiency anemia, and sideropenic anemia is also frequent after subtotal gastrectomy. In this study, thirty-three patients who underwent subtotal gastrectomy for primary adenocarcinoma of stomach were follow-up for at least 3 years, and included in this analysis. The presence of atrophic gastritis and H. pylori infection were detected by biopsy sampling and endoscopy every year after surgery. The iron status was evaluated by the assay of serum ferritin, serum iron and hemoglobin level. Statistical analysis revealed that atrophic gastritis was associated with lower iron serum levels, and gastric stump H. pylori infection was related to lower serum ferritin levels; on the contrary, no correlation of these factors with sex, age, malabsorption symptoms and stage of tumor was found. Atrophic chronic gastritis and Helicobacter pylori infection seem to play an important role as possible causes of post gastrectomy anaemia.  相似文献   
22.
Nonocclusive intestinal ischemia in patients with acute aortic dissection   总被引:3,自引:0,他引:3  
BACKGROUND: In aortic dissection, visceral complications that result from aortic branch compromise have been described extensively, whereas intestinal ischemia not associated with the false lumen anatomy has rarely been discussed. The aim of this report is to identify clinical factors that may contribute to the development of this form of acute mesenteric ischemia, to profile the patients at greatest risk, and to review diagnostic and treatment methods that emerged from our experience. METHODS: With a computerized database, we identified 371 patients who underwent treatment in our institution with a diagnosis of aortic dissection between July 15, 1985, and January 10, 2001. Mesenteric ischemia was present in 73 patients (19%). In 36 patients (9%), bowel ischemia was not associated with a false lumen anatomy or an extension of the dissection process. From a general analysis of the determinants of mesenteric ischemia in aortic dissection, we investigated, with univariate and multivariate analysis, the specific characteristics of these patients with nonocclusive ischemia. A retrospective analysis of the oxygen metabolic profile of patients who underwent operation also was performed. RESULTS: The mortality rate in patients with nonocclusive mesenteric ischemia was 86%; sepsis and multiple organ failure were the causes of death in all nonsurvivors. Surgical treatment was beneficial only in the early phases of the disease. The results of the multivariate analysis showed the multifactorial origin of nonocclusive mesenteric ischemia; cerebral ischemia, thrombosis of the false lumen, severe coagulation disorders, chronic obstructive pulmonary disease, aortic calcinosis, prolonged hypotension, chronic renal insufficiency, and low cardiac output were independent predictors of the condition. In patients who underwent operation, the significant risk factors were severe coagulation disorders, postoperative cerebral ischemia, maximal oxygen extraction rate of more than 0.40, aortic calcinosis, chronic obstructive pulmonary disease, thrombosis of the false lumen, inotropic support, and chronic renal insufficiency. An oxygen extraction rate of more than 0.4 at 6 hours after operation was found to be an index of intestinal damage sufficient to initiate an evaluation for visceral ischemia. Significant differences with occlusive ischemia also were evidenced with this study. CONCLUSION: In aortic dissection, nonocclusive mesenteric ischemia shows some unique clinical and individual predisposing factors. Most instrumental investigations are of poor diagnostic value, and prognosis is poor, especially when mesenteric gangrene had already taken place. Prevention can be exercised only with a heightening of our awareness of this condition and with timely correction of metabolic disturbances. In suspected cases, an aggressive surgical attitude may represent the only means for reducing mortality.  相似文献   
23.
The present study aimed at investigating whether in gastric cancer patients stage migration occurs with extension of lymphadenectomy, when node metastases are staged according to the new pN classification (UICC 1997). The investigation involved 921 patients, who underwent R0 gastric resection for gastric cancer between 1988 and 1998 in three different Italian centres: Verona (n=236), Forlì (n=409), Siena (n=276). The relation among lymphadenectomy and pN category was assessed by Kendall's partial rank-order correlation coefficient, controlling for depth of tumour invasion. A direct evaluation of the Will Rogers phenomenon was accomplished in the Verona series, by comparing the number of positive nodes actually observed with the number of positive nodes which would have been retrieved by a less extended lymphadenectomy (D1). The number of positive nodes increased remarkably with the enlargement of lymphadenectomy, especially in pT2 patients (from 2.2+/-3.9 in D1 to 3.9+/-5.0 in D3) and in pT3/pT4 patients (from 5.1+/-5.9 in D1 to 11.3+/-12.6 in D3). Non-parametric statistics highlighted a weak (Kendall's partial T=0.128) but significant (P<0.001) correlation between pN category and extension of lymphadenectomy. In the direct analysis of the Verona series, 22 patients out of 230 (9.6%) migrated to a lower pN tier when ignoring positive nodes retrieved from the second and third level. This percentage increased to 39.1% (90 out of 230) when adopting the TNM 87 classification. In conclusion stage migration is of minor importance in gastric cancer patients, staged according to the new pN classification.  相似文献   
24.
The differential diagnosis between benign and malignant pancreatic cystic lesions may be very difficult. We recently found that F-18-.uorodeoxyglucose positron emission tomography (18-FDG PET) was useful for the preoperative work-up of pancreatic cystic lesions. This study was undertaken to confirm these results. From February 2000 to July 2003, 50 patients with a pancreatic cystic lesion were prospectively investigated with 18-FDG PET in addition to helical computed tomography (CT) and, in some instances, magnetic resonance imaging (MRI). The validation of diagnosis was based on pathologic findings after surgery (n = 31), percutaneous biopsy (n = 4), and according to follow-up in 15 patients. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). The accuracy of FDG PET and CT was determined for preoperative diagnosis of malignant cystic lesions. Seventeen patients had malignant cystic lesions. Sixteen (94%) showed increased 18-FDG uptake (SUV >2.5), including two patients with carcinoma in situ. Eleven patients (65%) were correctly identified as having malignancy by CT. Thirty-three patients had benign tumors: two patients showed increased 18-FDG uptake, and four patients showed CT findings of malignancy. Sensitivity, specificity, positive and negative predictive value, and accuracy of 18-FDG PET and CT in detecting malignant tumors were 94%, 94%, 89%, 97%, and 94% and 65%, 88%, 73%, 83%, and 80%, respectively. 18-FDG PET is accurate in identifying malignant pancreatic cystic lesions and should be used in combination with CT in the preoperative evaluation of patients with pancreatic cystic lesions. A negative result with 18-FDG PET may avoid unnecessary operation in asymptomatic or high-risk patients. Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004 (oral presentation). This study was supported by the Ministero Università e Ricerca Scientifica (Cofin 2001068593-001), Rome, Italy.  相似文献   
25.
By means of an autoradiographic technique employing 14C-2-deoxyglucose, abnormalities of local brain glucose utilization were studied 90 minutes following occlusion of the left middle cerebral and common carotid arteries in a series of pentobarbital-anesthetized cats. Sham-insulted control animals exhibited a normal pattern of regional glucose utilization. In animals with vascular occlusion, a zone of greatly suppressed glucose utilization occupied the caudate nucleus of the ischemic hemisphere, with variable extension, and was surrounded by a narrow rim of increased local brain glucose utilization, suggesting the occurrence of enhanced anaerobic glycolysis in the latter zones. The cerebral cortex, which was less constantly affected, showed alternating regions of increased and decreased glucose utilization. Quantitation of local brain glucose utilization values from the contralateral nonischemic hemisphere revealed a mild suppression of cortical glucose utilization relative to the control animals. This may be the metabolic equivalent of diaschisis.  相似文献   
26.
A method for quantifying the outcome of goal-directed postural pointing was presented and used for relating the tremor output to the oscillations of single arm landmarks. The displacement of reflective markers placed on shoulder, upper arm, forearm, and hand were measured by an optoelectronic motion capture system in nine subjects holding a laser penlight pointed at a target. The high signal-to-noise ratio of the measured displacement series (from 7:1 for shoulder marker to 30:1 for hand marker) demonstrated the feasibility of the proposed system to carry out tremor analysis. The track of the laser emission on the target, reconstructed from penlight displacements, was studied as the outcome of the pointing task. By measuring the length and the dispersion of the path covered by the target track in 30 s, a significant and comparable tremor amplitude was found in vertical and lateral directions. The correlation between target track and arm tremor was stronger for distal than for proximal markers. Spectral and cross-spectral analyses evidenced the presence of a dominant low frequency oscillation (1.5 Hz), along with a high frequency one (5-7 Hz), in the displacement of the target track. These two components were significantly linked to the oscillations of the hand, the forearm and the upper arm but not to those of the shoulder, suggesting that the oscillations in the overall tremor output during the pointing task are mainly generated by the arm segments.  相似文献   
27.
The stereochemical course of the biotransformation of 1,2-monoepoxides of 4-vinylcyclohexene (2 and 3) by liver microsomes from control and induced rats and by purified P4502B1 and P4502E1 has been determined. The epoxidation of monoexpodies cis-4-vinylcyclohexene 1,2-epoxide (2) and trans-4-vinylcyclohexene 1,2-epoxide (3) gives the corresponding eight isomeric diepoxides cis-4-vinylcyclohexene diepoxide (9) and trans-4-vinylcyclohexene diepoxide (10). The stereoselectivity of this process is affected by P450 induction. Phenobarbital is able to enhance the yield of epoxidation to give preferentially diepoxide (1R, 2S, 4R, 7R)-trans-10b. This enantiomer is also formed as nearly the sole product by P450-catalyzed epoxidation of (1R,2S,4R)-trans-3b, the monoepoxide that, as a consequence of the selective formation from 4-vinylcyclohexene and/or reduced elimination by epoxide hydrolase, tends to accumulate in rat. Also, the P4502B1 but not 2E1, in a reconstituted system, is able to perform the epoxidation of (1R,2S,4R)-trans-3b to produce selectively the same diepoxide. Diepoxides cis-9 and trans-10 are biotransformed by mEH catalyzed hydrolysis. Although the hydrolysis of diepoxides 9 is characterized by a lower substrate enantioselection, the reaction of diepoxides 10 occurs with a good substrate enantioselectivity favoring the hydrolysis of the epoxides (1R,2S,4R,7S)-trans-10b and (1S,2R,4S,7S)-trans-10a. Diepoxide (1R,2S,4R,7R)-trans-10b is therefore the isomer primarily formed by P450-catalyzed oxidation of monoepoxide trans-3, and it is also the compound showing the lower propensity to undergo mEH-catalyzed hydrolysis. On the basis of this result, the ovotoxicity of 4-vinylcyclohexene is expected to be due to the stereoisomer diepoxide (1R,2S,4R,7R)-trans-10b, whose biological reactivity, via cross-linking, may be strongly different to the other isomer diepoxides, being dependent by its specific conformation.  相似文献   
28.
Cystic neoplasms account for about 10% of all cystic lesions of the pancreas and less than 1% of all exocrine pancreatic neoplasms. The authors report 4 cases of pancreatic cystadenoma (3 women and 1 man; mean age 59 years; range: 41-72), 2 serous and 2 mucinous, treated over the period from 1999 to 2002. The main symptoms were hypochondrial pain in two patients and diffuse abdominal pain in one while the fourth patient was asymptomatic. The patients were studied clinically by CT, echotomography and angiography. In three cases the tumours were located in the pancreatic body-tail, and in one case in the head. Serum amylase, lipase and tumour markers were all in the normal range. Only in one case was there an accurate preoperative diagnosis of tumour; in the other cases, a histological diagnosis was possible after surgical resection. Surgical treatment depended on tumour localisation: duodeno-cephalopancreatectomy for tumours in the head and distal pancreatectomy with splenectomy for tumours located in the body-tail, Lymphadenectomy at levels I and II was performed in all cases. There was no postoperative mortality and only one female patient developed postoperative acute pancreatitis. During the follow-up CT scans showed no recurrence of the pancreatic tumours. In agreement with the international literature, we hold that all cystic tumours of the pancreas should be treated by surgical therapy, above all because of the major differential diagnosis problems they continue to present. Conservative treatment is justified only for well documented asymptomatic serous cystadenomas.  相似文献   
29.
4-Hydroxyphenylretinamide (4-HPR) is a synthetic retinoid with minimal toxicity and favorable pharmacokinetics during long-term administration to patients in clinical trials. Since 4-HPR binds poorly to the retinoic acid receptors, the issue of whether 4-HPR exerts its biological actions via classical retinoid receptor pathways remains to be resolved. We have previously reported that stable expression of a truncated retinoic acid receptor alpha, RARalpha403, transduced in NIH 3T3 cells by a retroviral vector, rendered the cells resistant to retinoic acid for growth inhibition and induction of tissue transglutaminase (TGase II). Here, we report that stable expression of the dominant negative construct RARalpha403 fails to blunt growth inhibition and TGase II induction by 4-HPR, a potent chemopreventive retinoid, in the same cells. These data show that retinoic acid receptors do not mediate either growth inhibition or induction of TGase II activity by 4-HPR in mouse fibroblast cells.  相似文献   
30.
Three cases of primitive suprasellar germinomas are reported: the tumors show typical clinical signs (diabetes insipidus, visual disturbances and anterior pituitary dysfunctions), but CT findings are not so specific. It is very important to reach a correct diagnosis based on clinical and radiological findings, because of a very high radiosensibility of the tumor. The accuracy of preoperative diagnosis has been enhanced by CT in addition to conventional neuroradiological examinations. Due to the possible risk of meningeal spreading following biopsy, some authors prefer to avoid biopsy and to treat directly the patient by radiotherapy; a rapid reduction of the tumor size at the dose of 30 Gy suggests a possible germinoma.  相似文献   
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