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排序方式: 共有625条查询结果,搜索用时 15 毫秒
41.
Gol M Altunyurt S Cimrin D Guclu S Bagci M Demir N 《Journal of perinatal medicine》2004,32(4):342-345
Fetal gender has a significant effect on maternal and cord blood hCG levels, particularly during the last trimester of the pregnancy. However, the reason for this difference is obscure. The aim of the present study was to investigate whether term fetal hypophyseal - adrenal - gonadal axis differs between female and male fetuses thereby causing different hCG levels. The study consisted of 60 women with singleton pregnancies in the third trimester. Thirty-one pregnant women were carrying female fetuses, whereas 29 were carrying male. Human chorionic gonadotropin (hCG), estradiol, progesterone, testosterone, dehydro-epiandrosteron-sulfate (DHEAS), prolactin and growth hormone levels were measured in maternal serum and umbilical cord blood. In female bearing pregnancies maternal and cord blood hCG levels were significantly higher than in male bearing pregnancies (P<0.001). Maternal and cord blood estradiol, progesterone, testosterone, DHEAS, prolactin and growth hormone levels were not significantly different in either fetal gender. When all patients were considered as a group there were no correlations between fetal hCG levels and any of the measured hormones. Term fetal DHEAS, estrogen, progesterone, testosterone, growth hormone and prolactin levels do not contribute to different hCG levels between female and male fetuses. It is possible that fetal hypophyseal-adrenal gonadal axis does not play a central role as the cause of different hCG levels. 相似文献
42.
Altunyurt S Acar B Guclu S Saygili U Sakizli M 《The Journal of reproductive medicine》2002,47(12):1053-1054
BACKGROUND: Turner's syndrome (TS) is a sex chromosome disorder occurring in 1 in 2,500 female births and in approximately 50 in 100,000 adult females and is characterized by retarded growth, gonadal dysgenesis and infertility. The 45,X/46,XX chromosomal pattern is the most frequent mosaic type of this disease (36%). CASE: The mosaic form of TS was diagnosed in a 25-year-old, nulliparous woman whose major symptoms were menstrual irregularity and menorrhagia. She had normal development of secondary sexual characteristics and spontaneous menarche despite a very low amount (7%) of normal cells. CONCLUSION: Dysfunctional uterine bleeding is very uncommon in TS. Mosaic forms of TS may have very few features of TS despite a very low range of normal cells. 相似文献
43.
OBJECTIVE: To investigate the prognostic value of immunohistochemical detection of cathepsin D and the association between cathepsin D and established prognostic factors in endometrial carcinoma. METHODS: Cathepsin D immunoreactivity was determined by an immunohistochemical technique in a series of 79 patients with surgical stage I-III primary endometrial carcinoma. RESULTS: Of 79 tissue specimens, 48 (61%) showed a positive reaction for cathepsin D. A significant correlation between cathepsin D and histological grade was found (P < 0.05). The other established clinicopathological prognostic factors were not associated with cathepsin D. There was not any significant difference in prognosis between the positive cases and negative cases for cathepsin D (P > 0.05). In the univariate analysis cathepsin D immunoreactivity did not show significant prognostic value for overall survival (P > 0.05). The multivariate analysis also showed that cathepsin D was not related to patient outcome (P = 0.24, relative risk = 0.34, 95% confidence interval = 0.05-2.09). CONCLUSIONS: Our results suggest that cathepsin D immunoreactivity may not be of prognostic value but more studies are needed to evaluate the relationship between its immunoreactivity in tumor cells and in other cells. 相似文献
44.
Interventional radiology in the spleen 总被引:2,自引:0,他引:2
Despite the widespread use of interventional radiologic techniques, there has been reluctance to apply these to the spleen. Concern for bleeding and difficulty in negotiating around the colon and pleura have limited its use. The authors report their experience with interventional radiology of the spleen in 35 cases, including percutaneous biopsy (n = 5), diagnostic and therapeutic fluid aspiration (n = 14), and catheter drainage of abscesses (n = 9), hematomas (n = 2), intrasplenic pancreatic pseudocysts (n = 2), and necrotic tumor (n = 1). Transsplenic fluid aspiration and biopsy of the pancreas and adrenal gland were performed as well (n = 2). All procedures were performed under computed tomographic or ultrasound guidance. Biopsies were performed with 22- or 20-gauge needles only; no complications were encountered. Diagnoses included primary and secondary malignancies and an infectious process. Drainages were successful in 11 of 14 patients; pleural effusions occurred in two cases, but neither required specific therapy. Interventional radiologic procedures in the spleen are feasible, and the authors discuss methods to promote their safe application. 相似文献
45.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions. 相似文献
46.
Percutaneous cholecystography was performed on 13 children who had biliary system abnormalities: two had biliary hypoplasia, five had sclerosing cholangitis, three had cirrhosis, two had distal choledochal obstruction, and one had an obstructed portoenterostomy. In 12 patients transcholecystic cholangiography showed, without significant complications, the intra-and extrahepatic bile ducts. In one patient with primary sclerosing cholangitis, the intrahepatic bile ducts were not opacified satisfactorily; dilatation of the gallbladder required surgical drainage. The transcholecystic technique is indicated when the intrahepatic bile ducts are either mildly dilated or not dilated. 相似文献
47.
48.
49.
Kee F; McDonald P; Kirwan JR; Patterson CC; Love AH 《QJM : monthly journal of the Association of Physicians》1997,90(11):669-676
To determine the factors that influenced doctors' prioritization and
decisions on safe waiting time for coronary artery bypass surgery, 50
'paper patients', based on a random sample of cases who actually had
surgery, were assessed by 33 clinicians. We used linear regression models
to reflect the impact of clinical and non-clinical 'cues' on safe waiting
time and priority decisions. The benefits of surgery tended to be
over-estimated. For example, the average perceived gain in life expectancy
for patients with left main-stem disease was 6.74 years. However, models
incorporating only the perceptions of benefit as independent variables
(i.e. the anticipated symptom reduction, MI risk reduction and life
expectancy extension), had only modest explanatory power (mean R2 was 0.55
for safe waiting time, and 0.56 for priority decisions). Models which
incorporated perceptions of benefit and the cases' clinical and
non-clinical characteristics had generally much higher explanatory power
(mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables
had much less impact on the doctors' judgements than the major clinical
cues of angina severity and left main-stem stenosis. Demographic and
lifestyle cues had different impacts on safe waiting time and priority for
about 25% of doctors.
相似文献
50.
Thrombosis in inflammatory bowel disease: clinical setting, procoagulant profile and factor V Leiden 总被引:7,自引:0,他引:7
Jackson LM; O'Gorman PJ; O'Connell J; Cronin CC; Cotter KP; Shanahan F 《QJM : monthly journal of the Association of Physicians》1997,90(3):183-188
Patients with inflammatory bowel disease have an increased frequency of
thromboembolism, and microvascular thrombosis has been proposed as a
contributory pathogenic factor. The mechanism of enhanced procoagulant
activity is not understood. We examined the clinical setting of
thromboembolic events in 52 patients with Crohn's disease or ulcerative
colitis, and assessed the procoagulant laboratory profile, including Factor
V Leiden, in a subset of 20 patients to identify procoagulant risk factors.
Patients who developed thrombosis tended to be young; 60% of thrombotic
events occurred in patients under 50 years. Multiple thromboembolic
episodes occurred in 13% and unusual sites of thrombosis (e.g.
intracardiac, cerebral, inominate veins) in 11%. No risk factor was
identifiable in 52% of cases and two-thirds of thromboses occurred in an
out-patient setting. The mortality rate was 8%. Evidence for inflammatory
disease activity was found in only 45% of patients with ulcerative colitis
at the time of the thromboembolic event, in contrast to 89% of those with
Crohn's disease. Assays for specific coagulation defects were negative in
all cases tested (protein S, C were normal in 17/17; anti-thrombin III,
anti-phospholipid antibodies and activated protein C resistance were
negative in 20/20, and only 1/20 patients was found to be heterozygous for
Factor V leiden. Thrombosis in inflammatory bowel disease is important
because it occurs in a young population, often in unusual sites, and has a
high mortality. The development of thrombosis is related to active
inflammatory disease in most patients with Crohn's disease but apparently
not in those with ulcerative colitis. Since approximately half of the
patients had no other identifiable risk factor, there remains a substantial
group of patients with IBD who develop thrombosis for unknown reasons.
相似文献