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排序方式: 共有638条查询结果,搜索用时 31 毫秒
41.
Anatomy and pathology of the kidney by gray scale ultrasound 总被引:1,自引:0,他引:1
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OBJECTIVE: To determine the relative importance of thyroid hormones and human chorionic gonadotropin in the etiology of hyperemesis gravidarum. DESIGN: A prospective study comparing the hormonal status in women with hyperemesis gravidarum (5-18 weeks), with healthy pregnant controls, matched for gestational age. Sensitive thyroid stimulating hormone, free thyroxine, free triiodothyronine and total beta human chorionic gonadotropin were measured by immunoassays. The hormone results for hyperemesis gravidarum group (n=58) were compared with pregnant control women (n=58) using the Mann Whitney test. Stepwise logistic regression analysis was performed to determine which variables were significantly associated with hyperemesis gravidarum and to estimate the probability of each woman having hyperemesis gravidarum. The strength of the resulting association was tested by generating a receiver operating characteristic curve for predicting hyperemesis gravidarum using these probabilities. RESULTS: Maternal age and all hormones were significantly different between the hyperemetic and control groups. However, logistic regression analysis demonstrated that only maternal age, free thyroxine and thyroid stimulating hormone were significant independent variables. The area beneath the receiver operating characteristic curve for prediction of hyperemesis gravidarum was 0.84. CONCLUSION: Human chorionic gonadotropin is not independently involved in the etiology of hyperemesis gravidarum but may be indirectly involved by its ability to stimulate the thyroid. Differences in maternal age and thyroid function are highly discriminatory with regard to hyperemesis gravidarum. 相似文献
47.
McCullough JA Evoy D Sweeney KJ Meyers C Ravi N Keeling N Byrne PJ Reynolds JV 《Irish journal of medical science》2003,172(3):132-135
Background Gastric carcinoma is a significant cause of death in Ireland. Surgery offers the best option of cure, but the five-year survival
following resection remains dismal at 10–15%. Experience from Japan and from some Western units suggest that an extended (D2)
lymphadenectomy in association with gastrectomy increases the prospect of cure, but concern about the morbidity and mortality
of this operation and lack of evidence from randomised studies has limited its acceptance.
Aims This study reports the experience of a specialist upper gastrointestinal unit with D2 gastrectomy in a four-year audit.
Methods Sixty-two resections were performed for gastric cancer. Results Nineteen patients were deemed unsuitable for the D2 procedure
and underwent a more limited lymphadenectomy (DO or D1). Forty-three patients underwent D2 resection, 12 with an oesophagogastrectomy,
22 with total gastrectomy and nine with a sub-total distal resection. Eight patients undergoing D2 resection had extended
resections, five with splenectomy and three with a distal pancreatectomy. Post-operative complications occurred in 31% of
patients. Thirty-day and 90-day mortality were zero. Median survival was 822 days in the D2 group (range 120–1,320).
Conclusions These results show that a D2 gastrectomy can be performed with a low morbidity and mortality and a median survival of greater
than two years. 相似文献
48.
We used an optical technique to study haemodynamic changes associated with acoustically driven activity in auditory cortex of the chinchilla. Such changes are first detectable c. 0.5 s after stimulation, peak at 2-3 s, and decay within a further 3-6 s. This intrinsic signal imaging reveals activity in separate cortical areas, including primary auditory cortex (AI), secondary auditory cortex (AII) and an anterior auditory field (AAF). We have measured the timing of haemodynamics associated with each area, and find that AI has a different time course from AII and AAF; its haemodynamic change recovers more rapidly. We also show that within AI and AII, place specific activity related to acoustic stimulus frequency can be resolved by this optical imaging method. Our results show the close association between blood flow change and the local metabolic demands of neural activity. The data provide information about the potential of other functional imaging methods (e.g. PET, fMRI) which rely on activity related haemodynamic events. 相似文献
49.
KM RAI KJ PHILIPOSE VSM P TAKKAR RR BHONDE KK MAUDAR NK PANICKER 《Medical Journal Armed Forces India》1999,55(2):119-122
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts 相似文献
50.
Cloning of cDNA coding for connective tissue activating peptide III from a human platelet-derived lambda gt11 expression library 总被引:1,自引:1,他引:0
We report here the cloning of the cDNA coding for platelet connective tissue-activating peptide-III (CTAP-III) from a lambda gt11 expression library prepared using messenger RNA (mRNA) isolated from human platelets. The open reading frame of the clone coded for a protein with 128 amino acid residues. Since the precursor of CTAP-III, platelet basic protein (PBP is 94 amino acids long, the 5'-translated region of the cDNA codes for a leader sequence 34 amino acids long. This leader sequence, like the sequence of mature CTAP-III, shows significant homology to the sequence of platelet factor 4 (PF4), the only other platelet specific alpha-granule protein cloned until now, from a human erythroleukemic (HEL) cell line-derived cDNA library. These leader sequences are probably critical for targeting such proteins to the alpha-granule. Northern blot hybridization with platelet and megakaryocyte mRNA shows a single species mRNA of approximately 0.8 kb, suggesting that the corresponding cDNA is full length. The cloning of platelet specific CTAP-III provides additional evidence for the platelet specificity of the cDNA library used. 相似文献