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41.
Waterston–Cooley anastomosis may be carried out in patients with tricuspid atresia to provide pulmonary perfusion. It is associated with several complications, including preferential blood flow to the right lung, hypoplasia of the left pulmonary artery, obstruction of the anatomosis or rupture of pulmonary aneurysms. We study a patient with thrombosis in the pulmonary arteries following surgical construction of a Waterston shunt in childhood. Imaging findings and clinical symptoms are discussed with emphasis on echocardiogram‐gated multislice spiral CT. 相似文献
42.
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
43.
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
44.
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
45.
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
46.
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
47.
Thomasse Y Arends JP van der Heide PA Smit LM van Weerden TW Fock JM 《Nederlands tijdschrift voor geneeskunde》2005,149(15):826-831
Two previously healthy infants, a boy of 10 weeks and a girl of 4 months presented with apathy and muscle weakness. A third previously healthy child, a girl of 6 weeks old was admitted with respiratory insufficiency. None of the three had had a bowel movement for a number of days. After extensive investigations which revealed few abnormalities Clostridium botulinum toxin was obtained in serum from all three children. Type-B-toxin was shown in the faeces of the older girl and boy; both recovered quickly. The other girl had type-A toxin; she died. Two of the three children were given honey to comfort them. Infantile botulism must be considered in every infant with symptoms of constipation and hypotonia. The diagnosis can quickly be confirmed by electromyography with repetitive 50-Hz-stimulation. Honey is a well-known source of the C. botulinum spore and should not be given to children under the age of 12 months. These three children are the first cases to be described in the Netherlands. 相似文献
48.
49.
Rump P Lemmink HH Verschuuren-Bemelmans CC Grootscholten PM Fock JM Hayflick SJ Westaway SK Vos YJ van Essen AJ 《Neurogenetics》2005,6(4):201-207
Mutation analysis was performed in four apparently unrelated Dutch families with pantothenate kinase-associated neurodegeneration,
formerly known as Hallervorden-Spatz syndrome. A novel 3-bp deletion encompassing the nucleotides GAG at positions 1,142 to
1,144 of exon 5 of the PANK2 gene was found in all patients. One patient was compound heterozygous; she also carried a novel nonsense mutation (Ser68Stop).
The other patients were homozygous for the 1142_1144delGAG mutation. The 1142_1144delGAG mutation was also found in a German
patient of unknown descent. We used polymorphic microsatellite markers flanking the PANK2 gene (spanning a region of approximately 8 cM) for haplotype analyses in all these families. A conserved haplotype of 1.5 cM
was found for the 1142_1144delGAG mutation carriers. All the Dutch families originated from the same geographical region within
the Netherlands. The results indicate a founder effect and suggest that the 1142_1144delGAG mutation probably originated from
one common ancestor. It was estimated that this mutation arose at the beginning of the ninth century, approximately 38 generations
ago. 相似文献
50.
van der Heide JC Fock JM Otten B Stremmelaar E Hadders-Algra M 《Pediatric research》2005,58(3):586-593
The relationships between kinematic characteristics of sitting posture during reaching movements of the dominant arm and 1) the kinematics of the reaching movement itself and 2) functional performance during daily life activities (PEDI) were assessed in 51 sitting preterm children with cerebral palsy (CP). The children were 2-11 y, 33 had spastic hemiplegia (SH) and 18 bilateral CP (Bi-CP). The data were compared with those of 26 typically developing children (TD). Sitting posture before the onset of reaching of children with CP differed from that of TD children: they sat with a more reclined pelvis and a more collapsed trunk. The more reclined pelvic position was associated with a better quality of reaching movements. The different sitting postures of pelvis and trunk were not related to functional performance during daily life activities. Displacement of the head, trunk, and pelvis of the children with CP did not differ from that of the TD children. Nevertheless, in the children with CP a more stable head, a more mobile trunk, and a more stable pelvis were related to better functional performance and/or a better quality of reaching. This suggests that physiotherapeutic guidance of children with CP should focus rather on the latter postural parameters than on the different sitting posture of pelvis and trunk. 相似文献