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81.
82.
PURPOSE: This study examines the prognostic significance of circumferential margin involvement by tumor in resected specimens after potentially curative rectal cancer surgery. METHODS: During an eight-year period, all patients with rectal cancer were prospectively audited. For tumors of the middle and lower thirds of the rectum, a total mesorectal excision was performed; for tumors of the upper third, mesorectal excision proceeded at least 5 cm distal to the primary tumor. Resected specimens were subjected to careful histologic assessment, and patients undergoing curative procedures were entered into a surveillance program to detect both local and distant recurrence. RESULTS: Of 218 patients in the cohort, 9 had no resection, 14 underwent local excision, 1 had pre-operative radiotherapy, and 42 patients (20 percent) had palliative resections and were excluded from further analysis. This left 152 patients having a curative resection, of whom 20 (13 percent) had tumor within 1 mm of the circumferential margin. After follow-up until death or a median period of 41 months, recurrent disease was seen in 24 percent of patients with a negative margin and 50 percent with a positive margin. Both disease-free survival and mortality were significantly related to margin involvement (log-rank,P=0.01 andP=0.005, respectively). Local recurrence, however, was not significantly different in the two groups (11 and 15 percent, respectively; log-rank,P=0.38). CONCLUSIONS: When a mesorectal excision is performed, circumferential margin involvement is more an indicator of advanced disease than inadequate local surgery. Patients with an involved margin may die from distant disease before local recurrence becomes apparent.Read at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, June 22 to 26, 1997.Research was performed at the General Infirmary at Leeds, Leeds, United Kingdom.  相似文献   
83.
A 45-year-old male received wedge resection for his small hepatocellular carcinoma in April 1989 and extended right lobectomy for tumor recurrence 8 months later. Unfortunately, recurrent hepatic tumor with lung metastases were found 18 months after the second operation. Both the hepatic and pulmonary recurrent tumors were resected and transcatheter arterial embolization was added for the residual hepatic tumors. He remained symptom free for another 18 months. However, mediastinal lymphadenopathy, superior vena cava thrombus with superior vena cava syndrome, cardiac and brain metastases developed subsequently. He died of increased intracranial pressure. It is rare for hepatocellular carcinoma to have mediastinal metastases, superior vena cava thrombus and superior vena cava syndrome.  相似文献   
84.
SETTING: The treatment of severe acute respiratory syndrome (SARS) is at best controversial, although there is considerable anecdotal experience to show the benefits of corticosteroid therapy for selected patients. Some patients deteriorate relentlessly despite treatment with antibiotic, corticosteroid and mechanical ventilation. OBJECTIVE: To attempt to determine the clinical efficacy of pentaglobin, an IgM-enriched immunoglobulin preparation, on 12 severe SARS patients who continued to deteriorate despite corticosteroid and ribavirin therapy. DESIGN: Retrospective analysis of daily quantitative and radiographic data on the cohort in a regional teaching hospital. RESULTS AND CONCLUSION: There was significant improvement in radiographic scores, when compared with day 1, on days 5, 6 and 7 (P < 0.05) after commencement of pentaglobin treatment. Similarly, there was significant improvement in oxygen requirement, when compared with day 1, on days 6 and 7 (P < 0.05) after commencement of pentaglobin treatment. There were no reported adverse events attributable to pentaglobin administration. Ten patients made an uneventful recovery after treatment. One elderly man died from cardiorespiratory arrest despite clinical and radiological improvement, and another patient is making good progress. Pentaglobin is safe and probably effective in the treatment of steroid-resistant SARS. A double-blind placebo-controlled study should therefore be considered.  相似文献   
85.
The discordance between extremely high seroprevalence of Taenia solium antibodies in disease-endemic populations, relatively few symptomatic cases of neurocysticercosis, and high background levels of putatively inactive brain lesions (mainly calcifications) in seronegative controls have confused researchers, clinicians, and epidemiologists in the last decade. We reviewed longitudinal serologic data from general population serosurveys in 3 different disease-endemic areas of Peru and Colombia and found that approximately 40% of seropositive people were seronegative when resampled after 1 year (3 surveys) or after 3 years (1 survey). Transient antibodies may have significant implications for the epidemiology of and immunity to this disease.  相似文献   
86.
Diastolic dysfunction has been linked to 2 epidemics: atrial fibrillation (AF) and heart failure. The presence and severity of diastolic dysfunction are associated with an increased risk for first AF and first heart failure in patients with sinus rhythm. Furthermore, the risk for heart failure is markedly increased once AF develops. The evaluation of diastolic function once AF has developed remains a clinical challenge. The conventional use of Doppler echocardiography for the assessment and grading of diastolic dysfunction relies heavily on evaluating the relation of ventricular and atrial flow characteristics. The mechanical impairment of the left atrium and the variable cycle lengths in AF render the evaluation of diastolic function difficult. A few Doppler echocardiographic methods have been proved clinically useful for the estimation of diastolic left ventricular filling pressures in AF, but these appear to be underutilized. Several innovative methods are emerging that promise to provide greater precision in diastolic function assessment, but their clinical utility in AF remains to be established. In conclusion, this review provides an up-to-date discussion of the evaluation of diastolic function assessment in AF and how it may be important in the clinical management of patients with AF.  相似文献   
87.
Sodium-dependent intracellular pH (pHi) regulation was compared in granulosa cells from the three largest avian ovarian follicles by monitoring the pHi with biscarboxyethylcarboxyfluorescein, a dye whose fluorescence increases with alkalinity. Collagenase-dispersed granulosa cells obtained from the largest (F1), second largest (F2), and third largest (F3) preovulatory follicles about 2-3 hr prior to expected ovulation of F1 were used in the present study. The resting pHi measured in nominally bicarbonate free buffer with extra-cellular Na+ (Nao+ = 144 mM) and external pH (pHo) of 7.3 was about 6.8 in cells from F1, F2, and F3. There was no correlation between the stage of follicular development and the pHi whether the follicles were removed in the early or late preovulatory period. After acute cytoplasmic acidification by exposure of cells to nigericin in choline+ buffer, or by the abrupt removal of ammonium chloride, complete recovery of pHi occurred in 4-5 min. The rate and magnitude of the recovery were dependent upon the concentration of Nao+ and were abolished when Nao+ was replaced completely by choline+. Recovery in the presence of Nao+ was inhibited dose-dependently by amiloride (sodium-hydrogen exchange inhibitor). There was no difference between the rate and the extent of pHi recovery in acid-loaded cells obtained from F1, F2, and F3. Furthermore, by varying the concentration of Nao+ between 0 and 144 mM both young and matured granulosa cells extruded acid at the same rate. In addition, amiloride inhibited the Nao+ dependency of pHi recovery to a similar degree in F1, F2, and F3 cells. Our observations demonstrate in avian granulosa cells the existence of a Nao+-dependent, amiloride-sensitive pHi regulatory system that is equally effective in cells obtained from the three largest yolk-filled follicles.  相似文献   
88.
OBJECTIVES: Frequency occurrence of nonacidic and nonliquid reflux events in the pharynx has not been systematically studied. The aim of the present study was to characterize the physical (liquid, gas, and mixed gas/liquid) and pH properties of the gastroesophagopharyngeal refluxate. METHODS: We performed a total of 31 24-h simultaneous ambulatory pharyngoesophageal impedance and pH recordings in 11 GERD patients, 10 patients with reflux-attributed laryngitis, and 10 healthy controls. RESULTS: On average, the total number of reflux events (all kinds) in the pharynx was less than half of that in the proximal esophagus (18 +/- 4 vs 50 +/- 4, p < 0.01). Most of the pharyngeal reflux events were gas events and were observed in all three studied groups. Prevalence of these gas reflux events ranged between 0 and 74. The number of gas reflux events accompanied by a minor pH drop in laryngitis patients (1 (0-36)) was significantly higher than those in GERD and controls (0 (0-2) and 0 (0-1), respectively, p < 0.05). There was no significant difference in the number of nonacidic gas reflux events among the three groups (GERD: 10 (2-57), laryngitis: 11.5 (0-51), controls: 10.5 (0-27)). Impedance recording identified a total number of 566 events in the pharynx. Of these, a total of 563 events were compatible with gas reflux events, 101 events were accompanied by minor drops in intrapharyngeal pH, whereas 460 events were not accompanied by any pharyngeal pH change. CONCLUSIONS: Concurrent impedance and pH recordings detect significantly more events qualifying as reflux in the pharynx than pH recordings alone. A substantial majority of these events are gaseous refluxes both with and without minor pH drops. Gas reflux events with weak acidity appear to be more common among patients with reflux-attributed laryngeal lesions compared to GERD patients and controls.  相似文献   
89.
Abstract: Previous studies have shown that both plasma exchange (PE) and double filtration plasmapheresis (DFPP) are effective treatments in Guillain‐Barré syndrome (GBS). Whether PE and DFPP have similar effects in GBS is not clear. This report compares the therapeutic effectiveness of PE and DFPP in GBS patients treated in 3 major hospitals in northern Taiwan. A total of 102 patients were included in this survey, including 39 with PE (hereafter PE group) and 63 with DFPP (hereafter DFPP group). Both groups showed significant improvement of disability scores after treatment. However, time to onset of effect was shorter (5.6 ± 3.5 versus 7 ± 3.4 days, p < 0.05), and changes of disability scores were more prominent (1.3 ± 0.8 versus 0.8 ± 0.8, p < 0.05) in the PE group than the DFPP group. Mortality and outcome after 6 months were not different between the 2 groups. In conclusion, both PE and DFPP are effective treatments in GBS. PE was superior to DFPP in short‐term effectiveness. The long‐term effectiveness was not different.  相似文献   
90.
Mak JC  Ho SP  Leung RY  Ho PL  Ooi C  Tipoe GL  Yan C  Ip MS  Lam WK  Tsang KW 《Respiratory medicine》2005,99(10):1223-1228
Bronchiectasis is a chronic inflammatory and infective airway disease characterized by irreversible dilatation of the bronchi and persistent purulent sputum. Transforming growth factor-beta(1) (TGF-beta(1)) has been found to be increased in the lungs or bronchoalveolar lavage fluid of patients with inflammatory lung diseases. However, little is known on the serum TGF-beta(1) levels in patients with bronchiectasis. We aimed to determine the serum TGF-beta(1) concentrations in 95 patients with stable bronchiectasis (63 women; mean+/-sd age, 58.9+/-14.1 years) and 68 control subjects (23 women; 48.9+/-12.8 years) by ELISA, and to correlate with clinical parameters. The serum TGF-beta(1) levels were significantly higher in bronchiectatic patients compared with control subjects (median [range], 1812.5 pg/ml [1226.4-4114.5 pg/ml] vs. 1342.4 pg/ml [940.3-2371.7 pg/ml]; P<0.001). There was, however, no correlation between serum TGF-beta(1) levels with FEV(1) (% predicted), FVC (% predicted), 24h sputum volume, the number of bronchiectatic lung lobes or total white blood cell count (P>0.05). Our findings support previous indications that TGF-beta(1) may contribute to bronchiectatic airway inflammation. Further studies on the potential mechanisms and pathogenesis implications of this elevation should also be pursued in future.  相似文献   
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