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91.
M. Anselmino G. Zaninotto M. Costantini M. Rossi C. Boccu' D. Molena E. Ancona 《Surgical endoscopy》1997,11(1):3-7
Background: The Heller-Dor operation has recently been proposed for the treatment of esophageal achalasia even via a laparoscopic approach.
Methods: To measure the medium-term effectiveness of this new minimally invasive technique, an evaluation of pre- and postoperative
symptoms, esophagogram, endoscopic findings, esophageal manometry, and pH monitoring was prospectively designed in 43 patients
with primary esophageal achalasia. The mean clinical follow-up for all the patients is 12 months (range 3–43), while the mean
radiological follow-up is 11 months (range 1–23). Endoscopic data 1 year after surgery are currently available for 27 patients
(63%), whereas a 12-month (range 1–26) functional follow-up (including manometric and pH-monitoring studies of the esophagus)
is currently available for 35 patients (81.4%).
Results: No dysphagia was reported in 38 cases (88.4%); two (4.6%) complained of occasional swallowing discomfort which regressed
spontaneously; two (4.6%) had persistent dysphagia which regressed with pneumatic dilatation. One patient (2.8%) reported
mild occasional dysphagia after a 1-year asymptomatic period. Preoperatively, esophagograms showed an average maximum diameter
of 40.6 ± 9.1 mm which decreased to 24.1 ± 6.0 mm after operation. Mean lower esophageal sphincter (LES) resting and residual
pressures decreased significantly from 28.6 ± 10.7 mmHg to 8.8 ± 4.1 mmHg and from 17.0 ± 9.7 mmHg to 4.7 ± 4.0 mmHg, respectively
(p < 0.0001). These effects on esophageal diameter and LES function seem to persist over time. The complete absence of any peristaltic
contractions recorded preoperatively in all cases remained unchanged after surgery in all but four patients. However, this
rare recovery of peristalsis proved to be transient, and patients revealed a manometric impairment of their esophageal body
function, but without complaining of dysphagia. Twenty-four-hour pH monitoring showed abnormal gastroesophageal reflux episodes
in two (5.7%) of the 35 patients who were monitored: one was asymptomatic; the other had heartburn and endoscopically demonstrated
grade II esophagitis.
Conclusions: Laparoscopic Heller-Dor operation achieves excellent medium-term results which, together with the already-demonstrated advantages
of a minimal surgical trauma and rapid convalescence, validate the use of such a minimally invasive approach to treat patients
with primary achalasia of the esophagus.
Received: 19 March 1996/Accepted: 15 May 1996 相似文献
92.
S Savastano G P Feltrin D Miotto M Chiesura-Corona A Torraco L Castellan E Roman A B el Khatib F Cannito P Sandri 《La Radiologia medica》1992,84(5):608-612
This study was aimed at evaluating the efficacy of chemoembolization (CE) to improve survival in patients with hepatocellular carcinoma (HCC). Our results were compared with the natural history of HCC. Sixty-two consecutive patients with HCC in Okuda's stages I and II underwent CE. Forty-seven patients were treated with CE alone; 9 patients had CE prior to surgery, and 6 patients had it after surgery because of recurrent HCC. One hundred and nine CEs (mean: 1.8 CEs/patient) were performed with Lipiodol UF, epirubicin and gelatin sponge. Actuarial survival was calculated considering Okuda's stage, neoplasm size, and evidence of pseudocapsule. The mean cumulative survival of the 47 patients treated with CE alone was 13.2 months; survival (+/- SE) at 12, 24 and 36 months was 0.75 (+/- 0.07), 0.46 (+/- 0.10) and 0.28 (+/- 0.12). Survival was not affected by Okuda's stage, neoplasm size, evidence of pseudocapsule (p > 0.05). Nevertheless, the patients with early HCC had better prognosis. Eighteen patients (42.9%) died during follow-up, 12 of whom (66.7%) from hepatic failure. The mean survival of patients with recurrence of HCC after surgery was 41 months (range: 24.8-74.9 months) since initial diagnosis of HCC, and 14.8 months (range: 7.1-29.6 months) since diagnosis of recurrence. Two of these patients died from hepatic failure. All the patients who underwent also surgery after CE are still alive (mean survival: 14.7 months). Histologic findings of resected specimens revealed viable neoplastic cells in all cases. Twenty-one major complications (20.2%) occurred in 18 patients (29%); the outcome of complications was favorable in all but one patient who died from sepsis. CE is a reliable and safe treatment for unresectable HCC. Small HCCs should be preferably treated with surgery or, alternatively, with percutaneous alcohol injection. 相似文献
93.
Giulio Jori 《Lasers in medical science》1990,5(2):115-120
The scope and potential of the photodynamic therapy of tumors can be enhanced through an adequate control of the factors which improve the selectivity of tumour targeting by the systemically injected photosensitizer and increase the efficiency of photosensitized tumour damage. Promising results are obtained by using hydrophobic photosensitizers which can be specifically transported and released to the tumour by serum lipoproteins, especially low-density lipoproteins. The photosensitizer molecule should possess those structural features which induce a high probability of photoactivation by 700–800 nm light, as well as a high yield of long-lived triplet state. The use of liposome-delivered Zn-phthalocyanine as a second generation phototherapeutic agent for tumours is proposed. 相似文献
94.
The effects of regular daily coffee consumption on liver enzymes were studied in a large number of subjects from the general population. In coffee drinkers, liver enzymes (gamma-glutamyl transferase, alkaine-amino transferase, and alkaline phosphatase) and serum bilirubin were lower than in non-coffee-drinking subjects or in those consuming less than 3 cups daily. The hypothesis proposed is that liver enzymes are a target for caffeine contained in coffee. 相似文献
95.
Sami Schiff Daniela Mapelli Antonino Vallesi Raffaele Orsato Angelo Gatta Carlo Umiltà Piero Amodio 《Clinical neurophysiology》2006,117(8):1728-1736
OBJECTIVE: This study aims to evaluate the efficiency of top-down and bottom-up processes in the extrastriate cortex of cirrhotic patients without overt hepatic encephalopathy (HE). METHODS: Reaction times (RTs), accuracy and event-related potentials (ERPs) were recorded during the execution of a visual Simon task in 17 cirrhotic patients and 10 healthy controls. Amplitude and latency of the P1 and N1 (indexes of bottom-up processes) and of the N2pc (index of top-down processes) were measured. RESULTS: Patients were slower than controls, and patients with minimal HE (MHE) were slower than patients without MHE. The distribution analysis of RTs showed that the Simon effect decays with slower RTs in all the groups and that the shape of the distribution was different in MHE patients. No differences were found between cirrhotic patients and controls for P1 and N1 amplitude and latency. In contrast, N2pc latency was delayed in cirrhotic patients compared to controls independently of MHE. CONCLUSIONS: In the extrastriate cortex of cirrhotic patients without HE, top-down processes are altered whereas bottom-up processes are preserved. SIGNIFICANCE: The analysis of exogenous and endogenous visual components of ERPs provides a model to study the functional dissociation between top-down and bottom-up processes inside the extrastriate cortex. 相似文献
96.
Liver uptake kinetics of 99mTc labelled millimicrospheres of human serum albumin (MM) was studied in 16 subjects. Every subject received four doses of MM intravenously. The uptake constant decreased progressively with increasing dose. The maximum liver removal capacity, a parameter which is independent of liver blood flow, was calculated according to the method of Iio and Wagner (1963). From these data we conclude that MM are taken up by the reticuloendothelial system (RES) with saturable kinetics, and they are suitable for clinical use to evaluate RES function in man. 相似文献
97.
98.
Caenazzo C.; Garbisa S.; Ceol M.; Baggio B.; Borsatti A.; Marchi E.; Gambaro G. 《Nephrology, dialysis, transplantation》1995,10(2):175-184
Glycosaminoglycan administration has favourable effects on morphologicaland functional renal abnormalities in different models. Thepossibility that exogenous glycosaminoglycans modulate glomerularmatrix synthesis was explored in both primary and SV40-MES13murine mesangial cell cultures. On both cell types, both low-molecular-weightheparin and different glycosaminoglycans showed dose-dependentinhibition of proliferation and increase of 35SO24 uptake.After 36 h the cell compartment contained a spectrum of 35S-moleculesof less than 200 kDa; under heparin treatment, the two main35SO24 components (high and medium MW) increased by 16and 37% respectively. Susceptibility to glycosidases revealedthat heparin promotes the expression of heparan sulphate andincreases that of chondroitin sulphate. Moreover, heparin modifiesthe expression of decorin and bigly-can, involved in adhesionand fibrillogenesis, while not affecting perlecan. The extracellularmatrix modulation in renal cells, for which the sulphation typeand ratio of heparin are crucial, may thus explain the beneficialrenal effects of heparin. 相似文献
99.
A 29-year-old man was admitted to the Department of Urology of the University of Padova with a diagnosis of prostatic adenocarcinoma. Cystourethrography showed a prostatic urethral obstruction, and CT scan demonstrated a low pelvic solid mass involving the prostate and the seminal vescicle. A radical prostatectomy was performed, and the prostate was found to be widely infiltrated by a neoplasia formed by tubules, papillary structures, and solid cords of cuboidal or flat elements, each having indistinct borders and scant cytoplasm, in a myxoid or fibrous stroma. "Schiller-Duval-like," PAS-diastase-resistant and alfa-fetoprotein hyaline bodies were present. An endodermal sinus (yolk-sac) tumor was diagnosed. There was infiltration of the periurethral prostatic ducts, prostatic urethra, and seminal vesicles and single lymph node metastasis. Testicular echotomography was negative. In spite of aggressive surgery and chemotherapy, the patient died 10 months after diagnosis. This is the third case in the literature after those presented by Benson and Michel. 相似文献
100.
A viscoelastic constitutive model for the periodontal ligament (PDL) capable of accounting for large strains, anisotropy, and inelastic time-dependent effects was developed. Anisotropy characteristics are determined by the composite nature of the tissue and, in particular, by the distribution of collagen fibres. Time-dependent viscous phenomena are due to microstructural modifications during loading, such as fluid fluxes moving through the solid matrix and the internal rearrangement of fibers and constitutive adaptation. The viscoelastic model presented here was implemented in a general purpose finite element code. In vitro experimental tests were carried out on the PDL specimens of adult pigs to obtain stress-relaxation and cyclic stress-strain curves. The comparison of experimental and numerical results revealed good correspondence and confirmed the capability of the formulation assumed to properly interpret the viscoelastic behavior of the PDL. 相似文献