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排序方式: 共有633条查询结果,搜索用时 15 毫秒
1.
An anomalous pulmonary vein draining into the subdiaphragmatic inferior vena cava was initially demonstrated on computed tomographic (CT) scans. The diagnosis of scimitar syndrome was confirmed with digital subtraction angiography. In retrospect, the anomalous vein and dextroposition of the heart were shown on chest radiographs. 相似文献
2.
Dr. Gerold Wetscher MD Elizabeth Redmond MD Christine Watfah MD Galen Perdikis MD Michael Gadenstätter MD Rudolph Pointner MD 《Digestive diseases and sciences》1994,39(12):2511-2515
Bone disorders following gastrectomy were studied by measuring absolute and relative bone mineral density of the Wards triangle, serum 1,25-(OH)2-D, alkaline phosphatase, and total serum calcium. The subjects were 20 males who had undergone total gastrectomy not more than three months previously (group A1). Seventeen of these patients were reviewed three years later (group A2). Absolute and relative bone density were significantly lower in group A2 than in A1 (0.52 ± 0.011 g/cm2 versus 0.6 ± 0.014 g/cm2,P<0.01 and 85.5 ± 1.4% age-matched control versus 95 ± 1.3%,P<0.01). 1,25-(OH)2-D was significantly lower in group A2 than in group A1 (14.3 ± 0.97 pg/ml versus 20.6 ± 1.02 pg/ml,P<0.01). There was no difference in alkaline phosphatase and calcium serum concentration. The mean weight loss was 6.26 ± 0.57% over the follow-up period, and weight loss correlated with absolute and relative bone density (r=–0.74,P<0.01). There was a positive correlation between 1,25-(OH)2-D and absolute or relative bone density (r=0.67,r=0.62 andP<0.01). These data suggest that bone density decrease has already occurred three years after total gastrectomy and is positively correlated to 1,25-(OH)2-D deficiency. As no differences in serum alkaline phosphatase and serum calcium concentration were found, these factors are of little value for the early detection of postgastrectomy bone disorders, whereas weight loss is a valuable screening parameter. 相似文献
3.
D Mahalanabis H Ashraf MM Rahman GJ Fuchs 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(11):1113-1115
One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1 ) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea. 相似文献
4.
Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis 总被引:7,自引:2,他引:7
Li DY; Toland AE; Boak BB; Atkinson DL; Ensing GJ; Morris CA; Keating MT 《Human molecular genetics》1997,6(7):1021-1028
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular
disease that affects the aorta, carotid, coronary and pulmonary arteries.
Previous molecular genetic data have led to the hypothesis that SVAS
results from mutations in the elastin gene, ELN. In these studies, the
disease phenotype was linked to gross DNA rearrangements (35 and 85 kb
deletions and a translocation) in three SVAS families. However, gross
rearrangements of ELN have not been identified in most cases of autosomal
dominant SVAS. To define the spectrum of ELN mutations responsible for this
disorder, we refined the genomic structure of human ELN and used this
information in mutational analyses. ELN point mutations co-segregate with
the disease in four familial cases and are associated with SVAS in three
sporadic cases. Two of the mutations are nonsense, one is a single base
pair deletion and four are splice site mutations. In one sporadic case, the
mutation arose de novo. These data demonstrate that point mutations of ELN
cause autosomal dominant SVAS.
相似文献
5.
Profanter C Klingler A Strolz S Wetscher GJ Prommegger R Bodner E Riccabona G 《American journal of surgery》1999,178(5):374-376
BACKGROUND: In patients with primary hyperparathyroidism (HPTH) and previous thyroid operations, complications of parathyroidectomy are more frequent than in patients undergoing initial neck surgery. The aim of this study was to investigate the value of preoperative imaging with regard to its influence on the surgical strategy. METHODS: We retrospectively analyzed 17 patients with primary HPTH and previous thyroid surgery. Preoperatively 16 patients underwent sonography and/or scintigraphy. RESULTS: Sonography had an overall accuracy to correctly localize enlarged parathyroid glands of 80%, and scintiscanning had overall accuracy of 78.6%. The accuracy of localization was increased up to 84.6% if both diagnostic procedures were applied. In patients with normal thyroid residues the accuracy of sonography was 85.7%, and it was 100% if scintiscanning was used. CONCLUSIONS: Preoperative localization techniques in patients with primary HPTH and previous thyroid surgery have high accuracy. This allows for an imaging-directed operative strategy, thus preventing unnecessary bilateral neck explorations, which carry a high risk of recurrent laryngeal nerve injury. 相似文献
6.
The effect of medical therapy and antireflux surgery on dysphagia in patients with gastroesophageal reflux disease without esophageal stricture 总被引:11,自引:0,他引:11
Wetscher GJ Glaser K Gadenstaetter M Profanter C Hinder RA 《American journal of surgery》1999,177(3):189-192
BACKGROUND: Poor esophageal body motility and trapping of the hernial sac by the hiatal crura are the major pathomechanisms of gastroesophageal reflux disease (GERD)-induced dysphagia. There is only little knowledge of the effect of medical therapy or antireflux surgery in reflux-induced dysphagia. METHODS: Fifty-nine consecutive GERD patients with dysphagia were studied by means of a symptom questionnaire, endoscopy, barium swallow, esophageal manometry, and 24-hour pH monitoring of the esophagus. Patients had proton pump inhibitor therapy and cisapride for 6 months. After GERD relapsed following withdrawal of medical therapy, 41 patients decided to have antireflux surgery performed. The laparoscopic Nissen fundoplication was chosen in 12 patients with normal esophageal body motility and the laparoscopic Toupet fundoplication in 29 patients with impaired peristalsis. Dysphagia was assessed prior to treatment, at 6 months of medical therapy, and at 6 months after surgery. RESULTS: Heartburn and esophagitis were effectively treated by medical and surgical therapy. Only surgery improved regurgitation. Dysphagia improved in all patients following surgery but only in 16 patients (27.1%) following medical therapy. Esophageal peristalsis was strengthened following antireflux surgery. CONCLUSIONS: Medical therapy fails to control gastroesophageal reflux as it does not inhibit regurgitation. Thus, it has little effect on reflux-induced dysphagia. Surgery controls reflux and improves esophageal peristalsis. This may contribute to its superiority over medical therapy in the treatment of GERD-induced dysphagia. 相似文献
7.
We studied the relationship between nutritional status and infection due to specific enteropathogens in young children with diarrhoea. Overall, 26% of the children were severely underweight, 27% were severely wasted and 19% were severely stunted. Children with Shigellae and V. cholerae O1 were significantly more severely underweight, wasted and stunted than those with rotavirus diarrhoea ( p < 0:0001). Our results indicate that an effective nutrition programme for young children might have greater impact on diarrhoeal illness caused by Shigella and V. cholerae than by rotavirus diarrhoea. 相似文献
8.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
9.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
10.
马蓝的化学成分研究 总被引:15,自引:0,他引:15
Seven compounds have been isolated from the whole plant of Strobilanthes cusia (Nees) O. Ktze. Three of them are triterpenes (Ⅰ~Ⅲ), two are indole alkaloids (Ⅳ, Ⅴ), two are quinazolinone alkaloids (Ⅵ, Ⅶ). On the basis of spectral analysis and physicochemical properties, their structures were established as lupeol (Ⅰ), betulin (Ⅱ), lupenone (Ⅲ), indigo (Ⅳ), indirubin (Ⅴ), 4 (3H)-quinazolinone (Ⅵ), 2, 4 (1H, 3H)-quinazolinedione (Ⅶ). Ⅵ and Ⅶ were found from natural plant for the first time.The results of the pharmacological tests demonstrate that compound Ⅴ has anticancer activity and compound Ⅵ has hypotensive action. Compound Ⅶ can be quantitatively determined by HPLC, which may serve as a quality control standard for materia medica and its preparations. Compounds Ⅵ and Ⅶ have been confirmed by means of synthesis. 相似文献