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91.
Described in Switzerland in the early '60, the major features of hereditary non-polyposis colon cancer syndrome (HNPCCS) were established 20 years ago by H. T. Lynch. HNPCCS accounts for at least 60% of the colon cancer etiology. Cancer family syndrome is defined by the presence of extracolonic primary tumors in addition to colon cancer. Both syndromes are transmitted by an autosomic dominant pattern. None of the known biomarkers are specific and/or sensitive enough to rely on their predictive values of patient's risks. A typical Swiss family was investigated on the basis of the cancer-prone family history. 21% of the family members observed over 5 generations presented one or more (30% of the cases) colo-rectal neoplasms at the age of 50. 55% of the tumors were right sided. Histologically, half of the tumors were mucinous. 30% of metachronous cancer appeared within 10 years. Polyps (1-3) and flat adenomas were associated to the lesion in 57%. Extra-colonic tumors appeared in 18% of family members and in half of the colon cancer patients. The sites of these tumors were the urinary tract, ovary, small bowel, breast and stomach. Two fibroblast strains of affected individuals were established. No increased tetraploidy was noted. Preliminary results suggest that this two strains are rather sensitive to ionising radiation. Often neglected, family history of colon cancer remains the major diagnostic and decision-making tool of a such syndrome. It will necessitate special treatment of affected subjects and early screening of the relatives.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
92.
Cystic meningiomas. Report of seven cases 总被引:1,自引:0,他引:1
Seven patients with cystic meningioma are reported. The computerized tomography appearance of these meningiomas may mimic that of a glial or metastatic tumor with cystic or necrotic changes, and lead to an incorrect presumptive diagnosis. Radiological evaluation and recognition are important for the surgical removal of these potentially curable neoplasms. 相似文献
93.
The course of respiratory exchange through arterial blood gas analysis after coronary bypass-grafting and valvular replacement has been investigated in a cohort of 62 patients. Arterial blood gases were measured at baseline (the day before surgery), and then 1, 2, 3 and 9 days after surgery; in a subset of 18 patients, randomly selected from the same population, pulmonary function tests were also performed at baseline and repeated on day 9. Arterial blood gases showed a remarkable prevalence of hypoxaemia (as defined as arterial PaO2 less than 60 mmHg): 31% on the first, 50% on the second, and 40% on the third post-operative day; anemia and desaturated mixed venous blood were also prominent findings during the first two days. Arterial PO2 resulted higher afterward, although its mean value then was significantly lower than baseline (81.5 +/- 8.8 vs 93.1 +/- 9 mmHg, p less than 0.005). Pulmonary function tests evidenced widespread restrictive changes, with alterated thoraco-pulmonary mechanics (loss of more than 40% of vital capacity and one second forced expiratory flow) and parenchimal lung damage (residual volume and CO diffusion capacity decrease). Some differences in PaO2 course between coronary patients and valvular patients have been releaved; the mean basal PaO2 value of valvular was significantly lower then the other one (86.7 +/- 10.8 vs 94.7 +/- 10.9, p less than 0.05). 相似文献
94.
Hypercalcaemia and pancreatic ultrastructure in cats. 总被引:3,自引:0,他引:3
OBJECTIVE--To study the effects of local and systemic infusions of calcium on the ultrastructure of the pancreas in cats. DESIGN--Controlled study. INTERVENTIONS--Three groups of four cats each had local infusions (into the splenic artery) of calcium gluconate 0.6 mmol/kg.hour or potassium chloride 1.1 mmol/kg.hour, or sodium chloride 0.9%, for three hours. Two groups of eight cats each had systemic infusions (into the jugular vein) of either calcium gluconate 0.6 mmol/kg.hour or sodium chloride 0.9%, for twelve hours. In the group that was given calcium, the infusion rate was reduced after three hours to 0.3 mmol/kg.hour to maintain the hypercalcaemic state for a further nine hours. RESULTS--Local infusion of calcium caused destruction of acinar cells with hydropic degeneration of nuclei, discharge of cell organelles into the interstitial spaces, and extravasation of red blood cells but no apparent damage to the capillaries. There were no ultrastructural changes of any importance in the groups that received potassium or sodium chloride. Systemic infusion of calcium resulted in a 1.8 fold increase in the ionised calcium concentration in the serum, progressive signs of overstimulation of the Golgi apparatus with hypertrophy, fusion of condensing vacuoles, and disruption of the acinar cell polarization. This was followed by clumping of nuclear chromatin and destruction of acinar cells. CONCLUSION--Acute pancreatitis in cats can result from stimulation and destruction of acinar cells by hypercalcaemia. 相似文献
95.
P Barillari I A Muttillo I Cioè R Caronna M Ricci P Sammartino 《Minerva chirurgica》1992,47(20):1665-1670
Pleural mesotheliomas are rare, and their diagnosis and treatment not clear. The case observed in our Department leads us to an analysis of the literature. This showed that differential diagnosis with pulmonary carcinoma is very difficult, even in cases of parietal mesothelioma; however local treatment may be performed even in malignant mesothelioma. 相似文献
96.
H M Blottière A Menoret C Burg J Y Douillard J Le Pendu 《International journal of cancer. Journal international du cancer》1992,50(2):315-320
Sera from BDIX rats inoculated with 2 tumor clones derived from a single syngeneic colon carcinoma were assayed by Western blotting for the presence of antibodies against the grafted tumor. The PROb clone is progressive and produces metastases. We observed that rats bearing this tumor developed antibodies against an unglycosylated water-soluble protein of 105 kDa. The magnitude of this humoral response, as assessed by the intensity of the signal on immunoblots, was inversely correlated with survival of the rats. Furthermore, rats inoculated with the REGb clone, which is immunologically rejected, never developed detectable antibodies against the tumor. Antisera from rats injected with PROb tumor detected p105 antigen in cellular extracts from the REGb clone and from a series of rat and human cell lines. This protein was also detected in variable amounts in some normal adult and fetal tissues. Treatment of PROb or REGb cells by either interferon-gamma or heat shock did not significantly alter the expression of the p105 auto-antigen. 相似文献
97.
We investigated the effect of sex hormones on the sex-dependent response of rat kidney ornithine decarboxylase (ODC) activity to cadmium (Cd) administration and the involvement of the renin-angiotensin system in mediating stimulation of the liver enzyme by the metal. The response of renal ODC to Cd, which occurs in intact adult males but not in females, is also detectable in prepubertal and castrated males. Upon treatment with 17 beta-estradiol, the basal levels of enzyme activity in intact or castrated adult males were enhanced and Cd administration failed to increase them further. In adult females the kidney enzyme became responsive after ovariectomy. Also, in prepubertal females renal ODC was induced by Cd, and this was prevented by treatment with 17 beta-estradiol. Under the same conditions, changes in the levels of Cd accumulation within the kidney, that might account for variations in the response of ODC activity, did not occur. Cd caused an increase in renin activity starting minutes after its injection. Captopril, which specifically inhibits the conversion of angiotensin I to angiotensin II, prevented completely the induction of liver ODC by this metal; stimulation of the enzyme by Co was not affected by the drug. A similar inhibitory effect was exerted by propranolol. Adrenalectomy had no influence on the response of hepatic ODC to Cd; the decarboxylase was unaffected by aldosterone administration. It is suggested that Cd may induce liver ODC through the increase in angiotensin II following stimulation of renin by the metal. 相似文献
98.
D. le Nen O. Riot J. F. le Noach P. Caro C. Lefèvre 《Archives of orthopaedic and trauma surgery》1992,111(5):291-292
Summary A distally based posterior calf fasciocutaneous flap was successfully used to reconstruct a major ankle defect with exposed bones and joints. The flap, which reaches easily this region, can also be used as a free flap for coverage of heel and ankle when the forefoot is not involved in the injury. 相似文献
99.
M. Amgwerd M. Röthlin D. Candinas R. Schimmer H. P. Klotz F. Largiadèr 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(6):335-340
A number of studies have shown that ultrasound has an advantage over physical examination in the diagnosis of acute appendicitis. Most of these studies were conducted by experts in the field of ultrasonography. In this study the influence of experience on the results of the sonography of actue appendicitis were evaluated. All 203 patients admitted to our unit between December 1990 and December 1992 were examined physically and sonographically by a team of surgeons consisting of one experienced sonographer and six inexperienced surgical trainees. Laparotomy was performed in 136 patients (46%). Appendicitis was demonstrated histologically in 119 cases (39.4%). Initial clinical findings were positive in 87 (28.8%). Sonography was positive in 119 patients (39.4%). The 163 patients not operated on demonstrated other pathology on ultrasound in 60 cases (19.9%). The rate of negative laparotomies amounted to 7.2% in our study. Sensitivity and specificity for the sonographic diagnosis were 92% and 95%, respectively. They were only 81% and 80% for physical examination. Overall accuracy was 92% for sonography. Sensitivity and specificity for the inexperienced surgeons were 87% and 93%, respectively, while the experienced surgeon reached values of 97% and 98%, respectively. The results of both groups are comparable with values in the literature, suggesting that ultrasound evaluation of appendicitis is not a diagnostic tool limited to a few experienced sonographers. 相似文献
100.