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61.
We compared the efficacy of a single dose of an oral solution of levodopa methyl ester (ME) to that of standard levodopa, in the form of a single dose of Madopar, in reversing afternoon "off" periods in 12 patients with Parkinson's disease (PD). The highly soluble ME solution led to a significantly more rapid reversal of "off" periods. This preparation may therefore convey a clinical advantage in patients experiencing motor fluctuations whilst taking multiple daily dosages of levodopa, particularly in those with long or highly variable latency to the next "on" period.  相似文献   
62.
BACKGROUND: Conjugated linoleic acid (CLA) is a mixture of isomers of linoleic acid with conjugated double bonds that constitutes the most abundant fatty acid with conjugated dienes (CDs) in humans. CLA, erroneously considered in the past as a product of lipoperoxidation, has a dietary origin and has shown to possess anticarcinogenic and anti-atherogenic activity, mainly in animal studies. CLA can be metabolized to conjugated linolenic acid (CD18:3) and to conjugated eicosatrienoic acid (CD20:3) and these metabolites may be implicated in CLA activity. Because of the presence of dyslipidemia and the high incidence of cardiovascular and neoplastic diseases in uremic patients, we evaluated CLA and its metabolites in these patients in order to evaluate their metabolism and site distribution. METHODS: We measured CLA, CD18:3, CD20:3, CD fatty acid hydroperoxides (lipoperoxidation products), and linoleic acid in the plasma, adipose tissue, and red blood cell (RBC) membranes by using high-pressure liquid chromatography in the following groups: (1) 23 chronic renal failure (CRF) patients with creatine clearance (CCr)> 10 mL/min (26.2 +/- 16.7); (2) 21 end-stage CRF patients in conservative treatment with CCr <10 mL/min (6.8 +/- 1.8); (3) 30 hemodialysis (HD) patients; and (4) 30 healthy controls. RESULTS: The incorporation of CLA, CD18:3, and CD20:3 in RBC membranes was significantly reduced in group 1 and was even more reduced in groups 2 and 3. CLA significantly increased both in the plasma and adipose tissue of end-stage CRF patients only. CD18:3 and CD20:3 did not change in the plasma and adipose tissue of any group. No significant changes in linoleic acid and CD fatty acid hydroperoxides were found. CONCLUSIONS: The alterations of CD in CRF patients are not due to lipoperoxidation. The increased levels of CLA in plasma and adipose tissue of end-stage CRF patients may be due either to a reduced metabolization of CLA to CD18:3 and CD20:3, or to an altered site distribution with reduced incorporation in cellular membranes and accumulation in the plasma and adipose tissue. The clinical significance of these changes remains to be investigated.  相似文献   
63.
Purpose: To evaluate whether or not an intermediate dose of preoperative external radiation therapy intensified by systemic chemotherapy could improve the tumor response, sphincter preservation, and tumor control.

Methods and Materials: Between March 1990 and December 1995, 83 consecutive patients with resectable extraperitoneal adenocarcinoma of the rectum were treated with preoperative chemoradiation: bolus i.v. mitomycin C (MMC), 10 mg/m2, Day 1 plus 24-h continuous infusion i.v. 5-fluorouracil (5FU) 1000 mg/m2, Days 1–4, and concurrent external beam radiotherapy (37.8 Gy). All but 2 patients had T3 disease. Surgery was performed 4–6 weeks after the end of chemoradiation.

Results: Total Grade 3–4 acute toxicity during chemoradiation was observed in 11 (13%) patients: hematological Grade 3 toxicity was recorded in 8 (10%) patients, and Grade 4 toxicity was recorded in 2 (2%) patients. Grade 3 diarrhea was seen in 2 (2%) patients. No patient had major skin or urological acute toxicity. Two patients had no surgery: 1 died before surgery from septic complications after Grade 4 hematological toxicity; 1 refused surgery and is still alive after 6 years. There was no postoperative mortality and the overall perioperative morbidity rate was 25%. The analysis of tumor response involved 81 patients. Overall, 9% [7] of 81 patients had a complete pathologic response. Comparing the stage at the diagnostic workup with the pathologic stage, tumor downstaging was observed in 46 (57%) patients. We had 7 (9%) pT0, 5 (6%) pT1, 33 (41%) pT2, and 36 (44%) pT3. Nodal status downstaging was detected in 46 patients (57%). No evidence of nodal involvement was observed in 59 patients (73%). The incidence of tumor response was affected significantly by the number of quarters of rectal circumference involved (p = 0.03) and, marginally, by the length of the tumor (p = 0.09). The distance between the lower pole of the tumor and the anorectal ring had no influence. Of the patients, 63 (78%) had a sphincter-saving surgical procedure. In 12 (44%) of 27 patients candidate for an APR, the sphincter was preserved, as it was in 19 (95%) of 20 probable candidates. Lengthening of the distance between the anorectal ring and the lower pole of the tumor > 20 mm was observed in 21 patients (26%). Of 63 patients, 4 (6%) had moderate soilage after the sphincter-saving procedure.

Conclusion: Preoperative combined modality therapy seems to afford some potential advantages in nonrandomized trials: patients are able to tolerate higher chemotherapy doses and they experience a lower acute toxicity. Tumor downstaging and resectability rates are high; sphincter preservation is feasible. Larger T3 tumors remained less influenced by this treatment; thus, taking into account the low toxicity rate recorded, a more aggressive schedule should be applied in these resectable tumors.  相似文献   

64.
Laparoscopic management of urachal cysts in adulthood   总被引:3,自引:0,他引:3  
PURPOSE: Managing persistent and symptomatic urachal anomalies requires wide surgical excision. Such intervention is recommended to prevent symptom recurrence and complications, most notably malignant degeneration. However, traditional open excision is associated with significant morbidity and prolonged convalescence. We report our experience with the laparoscopic excision of urachal remnants as a less morbid, minimally invasive surgical alternative. MATERIALS AND METHODS: Between October 1993 and December 1999, 4 patients with a mean age of 43.3 years who had a symptomatic urachal cyst underwent laparoscopic radical excision of the urachal remnant. Using 2, 10 mm. and 1 or 2, 5 mm. ports the urachus and medial umbilical ligaments were divided at the umbilicus cephalad to the cyst. The specimen, which included the urachus, cyst and medial umbilical ligaments, was then separated from the bladder dome with or without the bladder cuff and removed intact. We reviewed the perioperative records to assess morbidity, recovery and outcome. RESULTS: All 4 procedures were completed successfully. No intraoperative or postoperative complications were reported at a mean followup of 15 months (range 2 to 24). Mean operative time was 180 minutes (range 150 to 210) and average hospital stay was 2.75 days (range 1 to 4). Pathological evaluation confirmed a benign urachal remnant in each case. All patients resumed normal activity within 2 weeks. CONCLUSIONS: To minimize the morbidity of radical excision the laparoscopic management of benign urachal remnants in adulthood is efficacious and our preferred method of management.  相似文献   
65.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
66.
Macrolides are widely used antibacterial agents. Although generally well tolerated, they have a number of important additional pharmacological effects, which can sometimes result in significant adverse reactions. This review focuses on three of these side effects: the prokinetic action associated with stimulation of motilin receptors, the proarrhythmic effect due to prolongation of the QT interval of the electrocardiogram and the potential for drug interactions due to inhibition of drug metabolising enzymes. For macrolides that have obtained marketing authorisation in Italy, United Kingdom or United States of America, we also considered whether these actions are properly reported in the approved summaries of the product characteristics and tried to provide strategies to identify patients at risk of significant side effects when macrolides are administered.  相似文献   
67.
AIM: To assess the efficacy and safety of a heavy silicone oil (Densiron 68) in the management of inferior retinal detachment recurrence. METHODS: A retrospective non-comparative consecutive case series study. Forty-nine cases of complex inferior retinal detachment were treated using Densiron 68 heavy silicone oil (HSO) as the endotamponade. Our main purpose was anatomic reattachment following Densiron 68 removal. Functional outcomes, rate of recurrences, the presence of inflammatory complications and intraocular pressure alterations were evaluated. RESULTS: Forty-nine patients affected by complex retinal re-detachment were recruited. The mean follow-up was 7.6 (±1.5) mo. The mean best corrected visual acuity after Densiron 68 removal was 0.95 logMAR, standard error (SE: 0.068). Retinal reattachment was 61.2% after first surgery and 81.6% after second surgery. Nineteen cases (38.8%) had recurrences when intraocular heavy silicon oil was in situ, 26.3% (5 cases) of which involved the inferior retina. CONCLUSION: Densiron 68 ef?ciently fills the inferior retinal periphery and might lower the risk of inferior proliferative vitreoretinopathy development, in particular after a standard silicon oil tamponade that reduces the proliferative process in the upper quadrants of the retina.  相似文献   
68.
Cotard's syndrome is a neuropsychiatric disease characterized by a variety of nihilistic delusions, commonly associated with several psychotic and major affective disorders, and neurological diseases, including stroke, dementia, and mental retardation. A 39-year-old male with mental retardation developed Cotard's syndrome, following an important episode of fear. During admission to our neurological unit, the patient underwent an accurate assessment, including neuroradiological, clinical, and neuropsychological examinations. At the psychiatric evaluation, he presented nihilistic delusions, in which he negated the existence of his body parts and the existence of his family members. The neuropsychological assessment ruled out other possible causes of misidentification, including the post-traumatic stress disorder. Thus, since also organic causes of Cotard's syndrome were excluded, the correlation between fear and the syndrome has been postulated and the patient opportunely treated, using a multidisciplinary approach. Our case suggests that in predisposed individuals negative emotions, including fear, may lead to delusional syndromes.  相似文献   
69.
Adjuvant chemotherapy and endocrine therapy can induce early iatrogenic menopause or worsen pre-existing menopausal symptoms in breast cancer survivors (BCS). The second most frequent menopausal symptom after hot flushes is the genitourinary syndrome (GSM). Since hormone replacement therapy is contraindicated in BCS, vaginal laser might represent a new nonhormonal option for GSM. This study aims at evaluating the effectiveness of the fractional CO₂ vaginal laser for GSM in BCS compared with healthy women. This is a retrospective study on 135 postmenopausal women (45 BCS and 90 healthy women) who underwent fractional CO2 laser for GSM. Objective (VHI and VVHI) and subjective outcomes (VAS for dyspareunia and vaginal dryness and a pain questionnaire) were evaluated at baseline visit and at every follow-up visit. Subjective and objective parameters improved significantly in both groups after laser therapy. The improvement was progressive and long-lasting up to 12 months after the end of the treatment. No severe adverse events were observed during the treatment. Fractional CO₂ vaginal laser induces a significant and long-lasting improvement on GSM symptoms in BCS. However, this improvement is slower than in healthy women undergoing the same treatment. Laser therapy turns out to be safe and well-tolerated.  相似文献   
70.
A dysregulated response of the neuroimmune system is a main contributor to the progression of neurodegeneration in Parkinson’s disease (PD). Recent findings suggest that protracted activating stimuli including α-synuclein, drive microglia to acquire maladaptive functions and to assume a harmful phenotype that prevail over a restorative one. Based on this concept, disease-modifying drugs should be aimed at targeting suppression of harmful-activated microglia and the associated production of neurotoxic molecules as pro-inflammatory cytokines, while sparing or inducing beneficial-activated microglia. In this study, we review current evidence in support of the beneficial effect of targeting peroxisome-proliferator-activated receptor (PPAR)-γ to achieve neuroprotection in PD. PPAR-γ agonists as rosiglitazone and pioglitazone are currently gaining increasing attention as promising disease-modifying drugs in this disorder. Early in vitro studies, followed by studies in in vivo models of PD, have provided convincing evidence that these drugs inhibit neuronal degeneration likely by selectively targeting the expression of neurotoxic factors in reactive microglia. Potential therapeutic application has been corroborated by recent report of pioglitazone neuroprotective activity in a non-human primate model of PD. All together, preclinical evidence have prompted the translation of pioglitazone to a phase II clinical trial in early PD.  相似文献   
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