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71.
BACKGROUND: Despite the sophisticated cross sectional image techniques currently available, a number of biliary stenosis or obstructions remain of an uncertain nature. In these pathological conditions, an "intrinsic" parietal alteration is the cause of biliary obstruction and it is very difficult to differentiate benign from malignant lesions using cross-sectional imaging procedures alone. We evaluated the efficacy of different endoluminal techniques to achieve a definitive pathological diagnosis in these situations. METHODS: Eighty patients underwent brushing, and or biopsy of the biliary tree through an existing transhepatic biliary drainage route. A subcoort of 12 patients needed balloon-dilatation of the bile duct and the material covering the balloon surface was also sent for pathological examination (balloon surface sampling). Pathological results were compared with surgical findings or with long-term clinical and instrumental follow-ups. Success rates, sensitivity, specificity, accuracy, confidential intervals, positive predictive value and negative predictive value of the three percutaneous techniques in differentiating benign from malignant disease were assessed.The agreement coefficient of biopsy and brushing with final diagnosis was calculated using the Cohen's "K" value. RESULTS: Fifty-six patients had malignant strictures confirmed by surgery, histology, and by clinical follow-ups. Success rates of brushing, balloon surface sampling, and biopsy were 90.7, 100, and 100%, respectively. The comparative efficacy of brushing, balloon-surface sampling, and biopsy resulted as follows: sensitivity of 47.8, 87.5, and 92.1%, respectively; specificity of 100% for all the techniques; accuracy of 69.2, 91.7 and 93.6%, Positive Predictive Value of 100% for all the procedures and Negative Predictive Value of 55, 80, and 75%, respectively. CONCLUSIONS: Percutaneous endoluminal biopsy is more accurate and sensitive than percutaneous bile duct brushing in the detection of malignant diseases (p < 0.01).  相似文献   
72.
Checketts  MR; Wildsmith  JAW 《CEACCP》2004,4(2):48-51
The last few years have seen increasing concerns among anaesthetistsabout the risks of pharmacological prophylaxis for thromboembolicdisease. Increased bleeding during or after surgery is one concern,but of greater significance is the possibility of an increasedpredisposition to haematoma formation when regional block isused. Most of the recent consideration of this problem has beenin relation to vertebral canal haematoma formation after centralnerve block. Some thought must be given also to the possibilityof haematoma formation after peripheral techniques when thetarget nerve is deeply placed so that pressure cannot be usedto control bleeding after needle insertion. However, this reviewwill be focused on vertebral canal haematoma.  相似文献   
73.
PURPOSE: To evaluate the safety, predictability, and efficacy of sutureless synthetic keratophakia (SSK) with PermaVision intracorneal lens (Anamed) implantation. SETTING: Ophthalmic Hospital, Rome, Italy. METHODS: This retrospective study analyzed the refractive outcomes in 10 eyes of 6 patients who had SSK with PermaVision lens implantation for spherical hyperopia (cylinder less than 1.0 diopter [D]). Preoperatively, the mean spherical equivalent (SE) refraction was +4.33 D +/- 1.52 (SD) (range +3.00 to +6.37 D). All procedures were performed using the Hansatome microkeratome (Bausch & Lomb) with a superior hinge except in 1 eye in which the flap was cut using the Amadeus microkeratome (Allergan) with a nasal hinge. RESULTS: Six months after PermaVision lens insertion, the mean SE refraction was +0.03 +/- 0.36 D (range -0.50 to +0.38 D), the mean uncorrected visual acuity was 0.85 +/- 0.13 (range 0.63 to 1.00), and the mean best corrected visual acuity was 0.99 +/- 0.19 (range 0.63 to 1.25). No eye lost lines of visual acuity. In 1 eye, the lens was acutely decentered and had to be explanted. CONCLUSIONS: Sutureless synthetic keratophakia with the PermaVision intracorneal lens is a new technique for the correction of hyperopia. It is easy to perform as well as reversible, and the learning curve of the experienced laser in situ keratomileusis surgeon is short. The technique was safe and effective for spherical hyperopia, but longer follow-up and additional cases are needed to draw conclusions about the efficacy of the technique.  相似文献   
74.
Bothropstoxin-I from Bothrops jararacussu snake venom is a lysine-49 phospholipase A(2) with myotoxic and neurotoxic activities. In this study, we used mouse phrenic nerve-diaphragm preparations in the absence and presence of manganese (Mn(2+)), a presynaptic blocker, to investigate a possible presynaptic action of bothropstoxin-I. At concentrations of 0.9 mM and 1.8 mM, Mn(2+) produced 50% neuromuscular blockade in less than 4 min., which was spontaneously reversible at the lower concentration. Bothropstoxin-I (1.4 microM) irreversibly inhibited neuromuscular blockade by 50% in 31+/-4 min. (mean+/-S.E.M., n = 9). Pretreating preparations with 0.9 mM Mn(2+) prevented the blockade by bothropstoxin-I. When added after bothropstoxin-I, Mn(2+) produced its characteristic blockade and, after washing, the twitch tension returned to pre-Mn(2+) levels, indicating that bothropstoxin-I caused irreversible damage before the addition of Mn(2+). Electrophysiological measurements showed that a concentration of bothropstoxin-I (0.35 microM), which did not produce neuromuscular blockade, caused the appearance of giant miniature end-plate potentials with no change in the membrane resting potential but increased the quantal content. Preparations preincubated with Mn(2+) (0.9 mM, 30 min.) were protected against the depolarizing action of bothropstoxin-I (0.7 microM). These results show that, in addition to its well-known myotoxic effect, bothropstoxin-I also has a presynaptic action.  相似文献   
75.
The number of positive axillary lymph nodes involved by tumor is one of the main prognostic factors for women with locoregional breast cancer (BC) for whom adjuvant chemotherapy is being considered. The prognostic importance of the ratio (P/D) between positive lymph nodes (P) and total dissected lymph nodes (D), previously demonstrated in the high-dose chemotherapy (HDC) setting has not yet been tested, however, in the conventional adjuvant chemotherapy setting. The data of 168 patients who were from 2 institutions and who were treated with adjuvant chemotherapy for BC were retrospectively analyzed, and univariate and multivariate analysis were performed, including the other traditional prognostic factors and P/D ratio as possible predictors of disease free survival (DFS). Disease-free survival for quartile 4 of P/D ratio (ratio >0.30) was statistically different from that for the other quartiles (log-rank test p < 0.001). Mean DFS for this series was not reached as well as for quartiles 1, 2, and 3, while mean DFS for quartile 4 was 44.5 months. In univariate analysis, number of positive lymph nodes (r2 = 0.055; p = 0.023), P/D ratio (r2 = 0.213; p < 0.001), and stage (r2 = 0.105; p = 0.002) were predictive of relapse, while in multivariate analysis, only P/D ratio remained an independent predictor of relapse (r2 = 0.213; p < 0.001). It is concluded that P/D ratio could become a simple, inexpensive, and easily available prognostic factor for patients undergoing conventional chemotherapy for BC.  相似文献   
76.
Apert Syndrome, also called acrocephalosyndactylia type 1, is characterized by craniostenosis with early fusion of sutures of the vault and/or cranial base, associated to mid-face hypoplasia, symmetric syndactylia of the hands and feet and other systemic malformations. CNS malformations and intracranial hypertension are frequently observed in these patients. Early surgical treatment aims to minimize the deleterious effects of intracranial hypertension. Fronto-orbital advancement, the usual surgical technique, increases the intracranial Volume and improves the disposition of encephalic structures previously deformed by a short skull. This study analyzes CNS alterations revealed by magnetic resonance in 18 patients presenting Apert Syndrome, and the conformational alterations in the encephalic structures after surgical treatment. The patients' age in February 2001 ranged from 14 to 322 Months (m=107). Image study included brain magnetic resonance showing ventricular enlargement in five cases (27.8%), corpus callosum hypoplasia in five cases (27.8%), septum pellucidum hypoplasia in five cases (27.8%), cavum vergae in two cases (11.1%) and, arachnoid cyst in the posterior fossa in two cases (11.1%). Absence of CNS alterations was noted in 44.4% of cases. A corpus callosum morphologic index was established by dividing its height by its length, which revealed values that ranged from 0.4409 to 1.0237. The values of this index were correlated to the occurrence or absence of surgical treatment (p=0.012; t=2.83). Data analysis allowed the conclusion that the corpus callosum morphologic measure quantified the conformational alterations of the cerebral structures determined by the surgical treatment.  相似文献   
77.
Cystic Fibrosis is the most common life-shortening autosomal recessive disease of Caucasian population. The clinical expression of the disease is heterogeneous and the treatment of CF patients requires high qualification of medical and paramedical staff. In 1992 and 1993, in Italy, two national laws (104/92 and 548/93) were enacted in favour of people affected by CF. Data gathered in the Italian Registry for CF (started on 1.1.1988) allow us to monitor changes occurred in the age structure of patients and diagnosis methods. This also thanks to the laws mentioned above. Data here presented refer to 4,209 patients, 1,964 of whom were alive on 1.1.1988, and 2,245 were diagnosed afterwards. A remarkable increase in early diagnosis (within the 3rd month of life) was noticed (from 41% to 65%), together with an increasing percentage of subjects who underwent a neonatal screening program (+34%). An increase in late diagnoses is also apparent: the frequency for patients diagnosed after 18 years of life ranged from 8% to 12%. The proportion of adult patients is more than doubled between 1988 (17%) and 2000 (41%) and the number of patients over 30 is now about 400. 512 patients died during the study period. Median age at death increased from 14 (1988) to 22 (2000) years. This trend can be observed also for patients diagnosed within the first year of life. All these changes have contributed in modifying age structure of CF population. In late 80's, the latter was mostly composed by children, while now 50% of patients are adolescents or adults. Therefore, it is now necessary to involve specialists of adult diseases in CF care.  相似文献   
78.
79.
Selecting the appropriate abutment can be both complex and confusing with the ever-increasing number of implant choices and transepithelial abutments available. Many restorative dentists resort to fabricating costly custom abutments to avoid the selection process. Although custom abutments are at times necessary, prefabricated abutments are usually more desirable. This article will describe the various abutments available and how to select the correct abutment for a given clinical situation in an organized, systematic fashion. Criteria discussed include implant position, angulation, soft tissue height, and interocclusal space. The latest modifications and developments in implant abutments are reviewed along with an indirect method of selecting abutments in a laboratory setting.  相似文献   
80.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
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