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201.
A patient with the typical features of neuroacanthocytosis is reported. Chorea, tics, personality changes and caudate atrophy on cranial MRI resulted in an erroneous diagnosis of Huntington's disease elsewhere. Attention to other features viz., absence of ocular motility disturbances, amyotrophy, areflexia, EMG evidence of axonopathy, raised serum creatinine phosphokinase (CPK) levels and the typical erythrocytic acanthocytosis enabled us to establish the correct diagnosis. The typical features of the disease as seen in the patient are discussed. In view of the implications for genetic counseling, careful clinical and laboratory evaluation is always warranted to exclude neuroacanthocytosis in all suspected cases of Huntington's disease.  相似文献   
202.
Microtubule-stabilizing agents are increasingly studied for cancer treatment based largely on the prior success of paclitaxel and docetaxel. In this review, we focus on the clinical development of epothilones and discodermolide, and we discuss salient preclinical and clinical highlights of these two novel natural products. These agents are distinguished by their biochemical features making them poor P-glycoprotein substrates and capable of inducing cytotoxicity in cell lines or in vivo tumor models harboring mutations in tubulin. There is now considerable data regarding the efficacy of the epothilones in human beings and discodermolide holds such promise, as well.  相似文献   
203.
An important question in neuroscience is whether and how temporal patterns and fluctuations in neuronal spike trains contribute to information processing in the cortex. We have addressed this issue in the memory-related circuits of the prefrontal cortex by analyzing spike trains from a database of 229 neurons recorded in the dorsolateral prefrontal cortex of 4 macaque monkeys during the performance of an oculomotor delayed-response task. For each task epoch, we have estimated their power spectrum together with interspike interval histograms and autocorrelograms. We find that 1). the properties of most (about 60%) neurons approximated the characteristics of a Poisson process. For about 25% of cells, with characteristics typical of interneurons, the power spectrum showed a trough at low frequencies (<20 Hz) and the autocorrelogram a dip near zero time lag. About 15% of neurons had a peak at <20 Hz in the power spectrum, associated with the burstiness of the spike train; 2). a small but significant task dependency of spike-train temporal structure: delay responses to preferred locations were characterized not only by elevated firing, but also by suppressed power at low (<20 Hz) frequencies; and 3). the variability of interspike intervals is typically higher during the mnemonic delay period than during the fixation period, regardless of the remembered cue. The high irregularity of neural persistent activity during the delay period is likely to be a characteristic signature of recurrent prefrontal network dynamics underlying working memory.  相似文献   
204.
205.
OBJECTIVE: To determine the safety and efficacy of targeted antitumor therapy with cisplatin/epinephrine injectable gel in patients with advanced squamous cell carcinoma of the head and neck. DESIGN: Two prospective, double-blind, placebo-controlled phase III trials of identical design. Crossover from blinded to open-label phase was permitted for patients with disease progression. SETTING: Tertiary referral centers in North America and Europe. PATIENTS: One hundred seventy-nine intensively pretreated patients with recurrent or refractory squamous cell carcinoma of the head and neck. INTERVENTION: Cisplatin/epinephrine injectable or placebo gel was administered by direct intratumoral injection; up to 6 weekly treatments. Dose was 0.25 mL of active or placebo gel per cubic centimeter of tumor up to 10 mL total. Patient benefit after local tumor control of the most symptomatic tumor was assessed by patients and physicians using the Treatment Goals Questionnaire. MAIN OUTCOME MEASURES: Local tumor response and patient benefit attributable to improvements in tumor-related symptoms. RESULTS: Combined results for the 178 patients with evaluable data in the 2 trials confirmed objective tumor responses in 35 (29%) of 119 patients, including 23 (19%) complete responses achieved with cisplatin/epinephrine gel, vs 1 (2%) of 59 for placebo (P<.001). Tumor response and patient benefit were significantly correlated (P=.006): 47% (17/36) of patients with target tumor responses achieved a rigorously defined benefit based on a prospectively selected treatment goal vs 15% (22/142) of nonresponders. CONCLUSION: Cisplatin/epinephrine injectable gel reduces tumor burden, ameliorates tumor symptoms, and provides a new therapeutic option for treating patients with squamous cell carcinoma of the head and neck.  相似文献   
206.
Neonatal spinal cord injury (SCI) is well described in the literature, though its diagnosis is often delayed or missed in the neonatal period. We present a neonate who was referred with upper gastrointestinal bleed and a diagnosis of spinal cord injury was subsequently made clinically and confirmed radiologically.  相似文献   
207.
Renal cell carcinoma in peritoneal dialysis patients   总被引:1,自引:0,他引:1  
Renal cell carcinoma is a rare but serious complication in ESRD patients. In these patients the incidence of renal cell carcinoma (RCC) is 20-40 times higher than in the general population. We performed a retrospective study to measure the incidence rate, prevalence, characteristics and survival among our peritoneal dialysis (PD) patients diagnosed with renal cell carcinoma. The study was carried out among 607 patients who were on the PD program from January 1997 to June 2002. RCC was detected in eight patients (four males and four females) with mean age of 52.1 +/- 10.6 years. Among these eight patients four were new cases that were diagnosed before the patients were started on dialysis (three in native kidneys and one in a transplanted kidney). In the other four patients the RCC was diagnosed after they had been on dialysis for 33-204 months (mean 60.75 +/- 50.48). We found an incidence rate of 1.3 per 1000 patients per year and a prevalence of 1.3%. Six of the eight patients had renal cysts. Tumor size was less than 7 cm in seven patients and in the other patient it was 8.5 cm. Seven of eight patients were alive at the time of study with a survival time ranging from 3-138 months (mean 122.25 +/- 88.2) months. In one patient, the RCC metastasised to the scalp, and, in two other patients, the tumors subsequently involved the second kidney. A cardiovascular complication was the cause of one death. Two patients received a renal transplant 36 and 66 months after diagnosis. We conclude that despite the low rate of metastases and mortality in our study, regular ultrasonography should be added to the follow-up of PD patients. Renal transplantation can be considered in these ESRD patients with RCC; however, close follow-up for metastases is recommended.  相似文献   
208.
In the present study, a new series of 2,6-diaryl-3-methyl-4-piperidones was synthesized by Mannich reaction (condensation) of ethyl-methyl ketone, substituted aromatic aldehydes and ammonium acetate. Oximes and thiosemicarbazone derivatives of 2,6-diaryl-3-methyl-4-piperidones were synthesized by reaction with hydroxylamine hydrochloride and thiosemicarbazide respectively. The chemical structures were confirmed by means of IR, 1H-, 13C-NMR and mass spectral data. The compounds were screened for acute toxicity, analgesic, local anaesthetic and antifungal activity. 2-(4-Methylphenyl)-3-methyl-6-(4-chlorophenyl)-piperidin-4-one 2 exhibited the highest analgesic and local anaesthetic activity. The oximes and thiosemicarbazones were completely devoid of analgesic and local anaesthetic activity. 2-(4-Methylphenyl)-3-methyl-6-(4-hydroxyphenyl)-piperidin-4-oxime 21 and 2-(4-methoxyphenyl)-3-methyl-6-(4-chlorophenyl)-piperidin-4-oxime 17 exhibited potent antifungal activity against Aspergillus niger. Antifungal activity against Candida albicans was observed only with 2-(4-dimethylaminophenyl)-3-methyl-6-(4-chlorophenyl)-piperidin-4-oxime 20. 2,6-Diaryl-3-methyl-4-piperidones did not exhibit antifungal property.  相似文献   
209.
In the present study, a series of 1-ethyl/benzyl-6-fluoro-7-(substituted piperazin-1-yl)1,4-dihydro-4-oxo-quinoline-3-carboxylic acid were synthesized and characterized by IR, 1H-NMR, mass spectral and elemental analysis. The in vitro antibacterial and antifungal activities of the compounds were evaluated by paper disc diffusion method. The minimum inhibitory concentrations (MIC) of the compounds were also determined by agar streak dilution method. The in vivo antibacterial activity of the compounds against Escherichia coli was also evaluated by mouse protection test. All the compounds exhibited significant antibacterial and weak antifungal activities. The in vivo antibacterial activity (ED50) against E. coli was 50-160 mg kg(-1) in the order of 7<9<8<10. 1-ethyl-6-fluoro-7-(2,5-dioxo-piperazin-1-yl)1,4-dihydro-4-oxo-quinoline-3-carboxylic acid (7) was found to exhibit the most potent in vitro antimicrobial activity with MIC of 4.1, 3.1, 3.1, 2.4, 1, 1, 25 and >100 microg mL(-1) against Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Bacillus cereus, E. coli, Klebsiella pneumoniae, Candida albicans and Aspergillus niger.  相似文献   
210.
Vertebral hemangioma is a vascular tumor most oftenly asymptomatic and of casual radiological discovery. More rarely, it can be aggressive, causing neurological complications and therefore requiring a convenient and sustained therapy where vertebroplasty is of essential importance. In this context, we report a case of an aggressive vertebral angioma of L4 which was responsible for lumbocruralgy. She underwent verterbroplasty and then had a very good outcome. In this way we deal with the the different technics of vertebroplasty, their advantages compared to other therapeutic medical, and or surgical methods, as well as their complications.  相似文献   
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