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101.
Victoria KM Tay Robert Fitridge Mark LH Tie 《Journal of Medical Imaging and Radiation Oncology》2002,46(2):163-166
Demographic, clinical and laboratory data were retrospectively collected from records of 146 cases of CT fluoroscopy‐guided chemical lumbar sympathectomy for the palliation of inoperable peripheral vascular disease (PVD) between January 1997 and August 1999. Of these, 16% had claudication, 39% had rest pain and 44% had ischaemic ulcers or gangrene. Seventy‐three percent of elective cases were outpatients. At 3 months, 27 cases were lost to follow up, leaving 119 cases. Within 3 months, improvement, defined as doubling of the walking distance, cessation of rest pain or healing of ulcers, occurred in 30.3% of cases. No change was observed in 45.4% of cases and 24.3% of cases deteriorated. Patients with ulcers or gangrene had significantly poorer results than those without any ischaemic lesions, as only 19% versus 39% of patients improved (P < 0.05). The presence of hypertension, diabetes mellitus, hyperlipidaemia and smoking had no value in predicting clinical outcome (P > 0.05). There were no major complications noted. CT fluoroscopy‐guided chemical lumbar sympathectomy is safe and effective, with a complication rate of less than 1%, and efficacy of at least 30% measured within 3 months. It is a simple and minimally invasive procedure, easily performed on an outpatient basis. CT fluoroscopy‐guided chemical lumbar sympathectomy should be considered for all patients in the early stages of inoperable PVD. 相似文献
102.
The execution of meaningless movement sequences was studied in 12 patients with lesions of the parietal cortex in comparison to the performance of age- and sex-matched controls. Five sequences of increasing complexity had to be performed by imitation and after verbal instruction. The performance errors were qualitatively scored by means of four error categories (temporal or spatial error, addition or omission of movement components). This study examined whether the error scores depended on instruction modality, movement complexity or lesion side. Patients with left parietal lesions produced more errors than those with right parietal lesions and control subjects. While additions or omissions of movement components occurred almost equally in all groups, temporal and spatial errors were more frequent in patients with left parietal lesions only. In addition, only the latter group showed a significant increase of error rates with increasing movement complexity. There were no significant differences between the contra- and ipsilesional hand in any group. These results demonstrate that lesions in the left parietal lobe lead to a disturbed spatio-temporal organisation of movement that becomes increasingly prominent for more complex movements. 相似文献
103.
Wisbeck JM Huffman LC Freund L Gunnar MR Davis EP Reiss AL 《Journal of developmental and behavioral pediatrics : JDBP》2000,21(4):278-282
Evidence of neuroendocrine dysfunction, behavioral features of social anxiety and avoidance, and neuroanatomical abnormalities suggest that abnormal hypothalamic-pituitary-adrenal (HPA) function may be a component of the fragile X (fra X) syndrome. In this preliminary study, salivary cortisol levels of males (n = 8, mean age = 13.5 yr) and females (n = 7, mean age = 13.9 yr) with the fra X full mutation were studied for 3 days. Day 1 was an experimental day, during which subjects experienced a Social Stressor task midmorning. Days 2 and 3 were routine days, during which the subjects were engaged in their typical activities. Saliva samples were collected before breakfast, lunch, dinner, and bedtime. On the experimental day, the prelunch sample collection occurred 30 and 90 minutes after the Social Stressor task. Compared with children's norms, the combined group of males and females with fra X had significantly higher cortisol levels in the prelunch and the prebedtime samples for the routine days. Comparisons between the two fra X groups for the experimental day revealed similar diurnal patterns for cortisol level. However, compared with females with fra X, males with fra X had significantly higher cortisol levels at two points during the day: 30 minutes after the social stressor and at bedtime. These preliminary data suggest that individuals with fra X have abnormal HPA function. Understanding the relations among HPA dysfunction, abnormalities in brain structure and/or function, and maladaptive behavior and cognition in fra X could inform the design of early interventions using pharmacological or environmental measures designed to normalize neuroendocrine function. 相似文献
104.
Dietary zinc deficiency in rats induces hyperplasia in the esophagus and
increases N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor
incidence. Previous work showed a direct relationship between epithelial
cell proliferation and esophageal tumor incidence in rats given multiple
doses of NMBA. We investigated the effects of single low doses of NMBA in
zinc-deficient rats since a single dose of 5.0 mg/kg was reported to be
non-carcinogenic in rats. Zinc-sufficient and deficient rats received a
single i.g. dose of NMBA at 0.5 or 2.0 mg/kg. At week 14, tumor incidence
was 50% with 0.8 +/- 1.0 tumors/rat, and 80% with 2.2 +/- 1.9 tumors/rat,
in deficient groups, D(0.5) and D(2.0), that received the lower and higher
dose, respectively. In addition, two small papillomas were found in one out
of eight untreated zinc-deficient rats. None of the NMBA-treated or
untreated zinc- sufficient rats had any tumors. Esophageal cell
proliferation, as determined by proliferating cell nuclear antigen (PCNA)
immunohistochemistry, showed that, irrespective of NMBA treatment,
deficient esophagi had significant increases in the number of labeled
cells, the total number of cells, and the labeling index, as compared with
zinc-sufficient ones. Mutations in Ha-ras and p53 genes in esophageal
tumors were detected by single strand conformation polymorphism (SSCP)
analysis. DNA sequencing of variant conformers revealed a point mutation
(GGA-->GAA, codon 12) in Ha-ras in 4/5 (80%) and 5/8 (63%) tumors, from
D(0.5) and D(2.0) rats, respectively. Three out of eight tumors from D(2.0)
rats exhibited SSCP mobility shifts within p53 exons 5 and 7: two tumors
(2/8, 25%) had missense mutations and the third, a silent mutation. Of the
two tumors with p53 mutations, one had a double mutation (transition at
codon 164, TCA-->TTA; transversion at codon 241, AGT-->TGT), and the
other tumor, a transition at codon 172 (AGA-->GGA), with amino acid
changes in all cases. In parallel with PCNA expression, elevated p53
expression was associated with hyperplastic and dysplastic regions, as well
as with tumors, in deficient esophagi. In short, these data indicate that
dietary zinc deficiency, with its associated sustained increased cell
proliferation in the esophagus, can drive an otherwise non-tumorigenic dose
of NMBA into a highly tumorigenic one.
相似文献
105.
Recently, the beneficial role of steroids for acute laryngotracheobronchitis has been more clearly defined for both intubated and unintubated patients. However, corticosteroids also improve the clinical signs of airway haemangiomata. Two patients are described who illustrate how this can be a source of diagnostic confusion. 相似文献
106.
107.
Gene therapy of metastatic colon carcinoma: regression of multiple hepatic metastases by adenoviral expression of bacterial cytosine deaminase 总被引:11,自引:0,他引:11
Block A Freund CT Chen SH Nguyen KP Finegold M Windler E Woo SL 《Cancer gene therapy》2000,7(3):438-445
Colon carcinoma accounts for 20% of deaths due to malignancies in the Western world. Once metastases occur, therapeutic options are limited, with an approximate 5-year survival of only 5%. To investigate the potential of new gene therapeutic approaches, a hepatic micrometastasis model of colon carcinoma in BALB/c mice was established. Inoculation of syngeneic MCA26 colon carcinoma cells into the spleens of 18- to 20-week-old mice resulted in the formation of multiple hepatic metastases. Selective transduction of developing hepatic metastases was demonstrated using a beta-galactosidase-expressing recombinant adenovirus. Cytosine deaminase (CD) can metabolize 5-fluorocytosine into the chemotherapeutic reagent 5-fluorouracil (5FU). The antitumoral potential of this suicide gene therapy approach was explored by systemic application of a recombinant replication-deficient adenovirus encoding for the bacterial CD gene under the control of the cytomegalovirus promoter (Ad.CMV-CD). Injection into the tail vein of tumor-bearing mice resulted in delayed tumor growth with significant reduction in hepatic metastases. The potential of this experimental approach for possible future clinical applications was evaluated by investigating adenoviral transduction efficiency, 5FU sensitivity, and 5-fluorocytosine-dependent Ad.CMV-CD toxicity in a variety of human colon cancer cell lines. Although the murine cell lines MCA26 and CC36 were highly sensitive to 5FU, the human colon cancer cell lines showed a 1-100 times higher resistance to 5FU. Specific Ad.CMV-CD toxicity correlates with 5FU toxicity. Transduction efficiency in human colon carcinoma cell lines was shown to be 10-1700 times higher compared with murine cell lines, thus compensating for 5FU resistance. In conclusion, suicide gene therapy using CD may be promising as an adjuvant treatment regimen for hepatic micrometastases of human colon carcinoma. 相似文献
108.
Outplacement service (OPS) is a human resource service provided by organizations to terminated executives. In addition to assisting organizations with the mechanics of the termination process, OPS helps terminated executives cope with the trauma of job loss and find new employment. Given the frequent involvement of nurse executives in termination decisions and the risk of termination inherent in their own positions, nurse executives have a vested interest in OPS policies and programs. 相似文献
109.
Colorectal hemangioma: radiologic findings 总被引:1,自引:0,他引:1
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma. 相似文献
110.
KM FOCK JY KANG HS NG TM NG KA GWEE CC LIM 《Journal of gastroenterology and hepatology》1995,10(4):379-382
Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine. 相似文献