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991.
Specific binding of the synthetic androgen, [17 alpha-methyl-3H]methyltrienolone, to the cytosol fraction of the submandibular salivary gland (SMG) of male mice was studied in relation to the developmental profiles of testosterone and thyroid hormones in blood. The peak rise of serum triiodothyronine (T3) at prepubertal age was closely related to both the increase of maximal androgen-binding capacity in SMG and the conspicuous surge of proliferative activity as indicated by increased rate of glandular DNA content. Also, 2-month thyroidectomized mice had an age-related, strong reduction in the number of androgen-binding sites. On the other hand, the development of the secretory functions of the gland could be better related to the rise of circulating testosterone by days 25-30 of age. The results suggest that thyroid hormones play a very important role in the early induction and further maintenance of androgen receptors in the murine SMG.  相似文献   
992.
Summary This study was undertaken in order to compare the usefulness of three indices of tumour proliferation in detecting primary hepatocellular carcinoma (HCC) and in differentiating this neoplasm from liver cirrhosis. In 10 patients with HCC and in 63 with liver cirrhosis serum -fetoprotein (AFP), tissue polypeptide antigen (TPA) and ferritin were assayed. Increased levels of AFP but not of TPA and ferritin were observed in HCC as compared to liver cirrhosis. The receiver-operating characteristic curves demonstrated that AFP is more discriminating between HCC and liver cirrhosis than the other two markers. Correlations between liver function tests and serum markers were observed in liver cirrhosis but not in HCC. We can conclude that AFP is more useful than TPA and ferritin in detecting HCC in patients with liver cirrhosis, owing to the high frequency of false positive results of the latter two indices in liver cirrhosis. Liver dysfunction is probably involved in increasing all these markers of malignancy, thus reducing the specificity of these tests.Abbreviations AFP -tetoprotein - TPA tissue polypeptide antigen - HCC primary hepatocellular carcinoma Partially supported by a grant of the Italian National Research Council, Special Project Oncology, contract 87.01.541.04. Under the auspices of the R. Farini association for gastroenterological research  相似文献   
993.
CD49d/alpha4-integrin is variably expressed in chronic lymphocytic leukemia (CLL). We evaluated its relevance as independent prognosticator for overall survival and time to treatment (TTT) in a series of 303 (232 for TTT) CLLs, in comparison with other biologic or clinical prognosticators (CD38, ZAP-70, immunoglobulin variable heavy chain (IGHV) gene status, cytogenetic abnormalities, soluble CD23, beta2-microglobulin, Rai staging). Flow cytometric detection of CD49d was stable and reproducible, and the chosen cut-off (30% CLL cells) easily discriminated CD49dlow from CD49dhigh cases. CD49d, whose expression was strongly associated with that of CD38 (P<.001) and ZAP-70 (P<.001), or with IGHV mutations (P<.001), was independent prognosticator for overall survival along with IGHV mutational status (CD49d hazard ratio, HRCD49d=3.52, P=.02; HRIGHV=6.53, P<.001) or, if this parameter was omitted, with ZAP-70 (HRCD49d=3.72, P=.002; HRZAP-70=3.32, P=.009). CD49d was also a prognosticator for TTT (HR=1.74, P=.007) and refined the impact of all the other factors. Notably, a CD49dhigh phenotype, although not changing the outcome of good prognosis (ZAP-70low, mutated IGHV) CLL, was necessary to correctly prognosticate the shorter TTT of ZAP-70high (HR=3.12; P=.023) or unmutated IGHV (HR=2.95; P=.002) cases. These findings support the introduction of CD49d detection in routine prognostic assessment of CLL patients, and suggest both pathogenetic and therapeutic implications for CD49d expression in CLL.  相似文献   
994.
儿童Lowe综合征OCRL基因突变2例报告   总被引:1,自引:0,他引:1  
目的探讨儿童Lowe综合征的临床特点和基因特征。方法分析2例Lowe综合征患儿的临床资料和OCRL基因检测结果,并复习相关文献。结果 2例患儿均为男性,均存在小分子蛋白尿、高钙尿症、佝偻病和肾结石。例2患儿还有轻度代谢性酸中毒、糖尿和隐睾症。例1患儿生后不久发现有视力异常和先天性白内障,并行手术治疗,同时存在精神运动发育落后,头颅磁共振成像(MRI)示胼胝体发育不良。例2患儿就诊时肾外症状不明显,但眼科检查发现有先天性白内障,头颅MRI示脑发育低下、脑白质髓鞘化延迟,且随访过程中逐渐出现智力发育落后。OCRL基因检测发现2个突变,例1为剪切位点突变NG 008638.1:g.46846-46848del TAA/ins C,例2为缺失移码突变NM000276.3:c.321del C,两种突变以前文献均未报道。结论 Lowe综合征的诊断主要通过临床表现和OCRL基因检测,对于有先天性白内障、肾小管病变的患儿需要与Lowe综合征鉴别。本研究发现2个OCRL基因的新突变。  相似文献   
995.
Raynaud’s phenomenon in undifferentiated connective tissue disease (UCTD)   总被引:1,自引:0,他引:1  
The aim of this study was to ascertain which clinical and immunological factors are associated with Raynauds phenomenon (RP) in patients with undifferentiated connective tissue disease (UCTD) and to investigate microvascular involvement. A total of 78 patients were evaluated. They all showed symptoms suggestive of a connective tissue disorder (CTD), but did not fulfil the criteria for any of the defined CTDs. They all had a disease duration of at least 1 year. Nailfold capillaroscopy (NC) was performed using a computerised videomicroscope. We diagnosed RP in 52.5% of our patients. Patients with RP showed a higher occurrence of oesophageal dysmotility (p=0.001) and anti-ribonucleoprotein (RNP) antibodies (p=0.004) than those without RP. The distinguishing capillaroscopic characteristics of UCTD patients with RP were widened and irregularly enlarged loops (75 and 55%, respectively), giant capillaries (35%), and less than two haemorrhages per finger (40%). The combination of features indicative of a slow scleroderma pattern was present in 18 of 40 patients with UCTD and RP (p=0.0003). Only 3 of the original 78 patients (3.8%) developed a definite CTD. In none of our patients did we observe avascular areas or changes from the original capillaroscopic pattern during follow-up examination. Our study indicates that patients with UCTD would seem to have a benign form of RP, since they show the absence of cutaneous complications, the existence of a mild microvascular damage and a stable nailfold capillary pattern. Further examinations of these patients will be required in order to confirm our findings.  相似文献   
996.
Aims/hypothesis The aim of this study was to investigate the effects of lifestyle intervention on the levels of plasminogen activator inhibitor (PAI-1) and fibrinogen in subjects participating in the Finnish Diabetes Prevention Study (DPS).Methods In five DPS centres, 321 subjects with impaired glucose tolerance (intervention group, n=163; control group, n=158) had their PAI-1 and fibrinogen levels measured at baseline and at the 1-year follow-up. Additional 3-year follow-up assessments were carried out in a sample of 97 subjects in one of the DPS centres (Turku). The intervention programme included an intensive lifestyle intervention aiming at weight reduction, healthy diet and increased physical activity.Results During the first intervention year, PAI-1 decreased by 31% in the intervention group but showed no change in the control group (p<0.0001). In the Turku subgroup, the decrease in PAI-1 persisted throughout the 3-year follow-up. Changes in PAI-1 were associated with the number of lifestyle changes made during the first year (p=0.008). Weight reduction was the most important factor explaining the decrease in PAI-1. Changes in fibrinogen levels did not differ between the groups.Conclusions/interpretation In addition to the previously reported reduction in the risk of type 2 diabetes in DPS participants with impaired glucose tolerance, the intensive dietary and exercise intervention had beneficial long-term effects on fibrinolysis as indicated by the reduced levels of PAI-1. These results suggest that elevated PAI-1 levels in obese subjects with impaired glucose tolerance are mostly reversible by lifestyle changes, especially those geared to weight reduction.  相似文献   
997.
Aims/hypothesis. We have previously shown that lactate protects brain function during insulin-induced hypoglycaemia. An adaptation process could, however, not be excluded because the blood lactate increase preceded hypoglycaemia.¶Methods. We studied seven healthy volunteers and seven patients with Type I (insulin-dependent) diabetes mellitus with a hyperinsulinaemic (1.5 mU · kg–1· min–1) stepwise hypoglycaemic clamp (4.8 to 3.6, 3.0 and 2.8 mmo/l) with and without Na-lactate infusion (30 μmol · kg–1· min–1) given after initiation of hypoglycaemic symptoms.¶Results. The glucose threshold for epinephrine response was similar (control subjects 3.2 ± 0.1 vs 3.2 ± 0.1, diabetic patients = 3.5 ± 0.1 vs 3.5 ± 0.1 mmol/l) in both studies. The magnitude of the response was, however, blunted by lactate infusion (AUC; control subjects 65 ± 28 vs 314 ± 55 nmol/l/180 min, zenith = 2.6 ± 0.5 vs 4.8 ± 0.7 nmol/l, p < 0.05; diabetic patients = 102 ± 14 vs 205 ± 40 nmol/l/180 min, zenith = 1.4 ± 0.4 vs 3.2 ± 0.3 nmol/l, p < 0.01). The glucose threshold for symptoms was also similar (C = autonomic 3.0 ± 0.1 vs 3.0 ± 0.1, neuroglycopenic = 2.8 ± 0.1 vs 2.9 ± 0.1 mmol/l, D = autonomic 3.2 ± 0.1 vs 3.2 ± 0.1, neuroglycopenic 3.1 ± 0.1 vs 3.2 ± 0.1 mmol/l) but peak responses were significantly attenuated by lactate (score at 160 min C = 2.6 ± 1 vs 8.8 ± 1, and 0.4 ± 0.4 vs 4.8 ± 1, respectively; p = 0.02–0.01, D = 1.3 ± 0.5 vs 6.3 ± 1.7, and 2.3 ± 0.6 vs 5.7 ± 1.1 p = 0.07–0.02). Cognitive function deteriorated in both studies at similar glucose thresholds (C = 3.1 ± 0.1 vs 3.0 ± 0.1, D = 3.2 ± 0.1 vs 3.3 ± 0.2 mmol/l). Although in normal subjects a much smaller impairment was observed with lactate infusion (Δ four-choice reaction time at 160 min = 22 ± 12 vs 77 ± 31 ms; p = 0.02), in Type I diabetic patients lactate infusion was associated with an improvement in cognitive dysfunction (0.2 ± 0.4 vs –38 ± 0.2 Δ ms, p = 0.0001).¶Conclusion/interpretation. A blood lactate increase after the development of hypoglycaemic symptoms reduces counterregulatory and symptomatic responses to insulin-induced hypoglycaemia and favours brain function rescue both in normal and diabetic subjects. These findings confirm that lactate is an alternative substrate to glucose for cerebral metabolism under hypoglycaemic conditions. [Diabetologia (2000) 43: 733–741]  相似文献   
998.
We describe a case of ruptured aneurysm of the right coronary sinus of Valsalva (ASV) diagnosed by transthoracic two-dimensional echocardiography which allowed to quickly establish a correct diagnosis in a patient with a recent onset of continuous murmur and acute right congestive heart failure.  相似文献   
999.
Bio-based composites made of poly(L-lactic acid) (PLLA) and β-cyclodextrin/d-limonene inclusion complex (CD-Lim) were prepared by melt extrusion. Encapsulation of volatile d-limonene molecules within β-cyclodextrin cages was proven to be a successful strategy to prevent evaporation during high-temperature processing. However, small amounts of limonene were released upon processing, resulting in the plasticization of the polymeric matrix. Morphological analysis revealed good dispersion of the filler, which acted as a nucleating agent, favoring the growth of PLLA crystals. The composites′ lowered glass transition temperature upon the addition of CD-Lim was also proved by thermomechanical analysis (DMA). Moreover, DMA revealed constant stiffness of modified materials at room temperature, which is crucial in PLLA-based formulations.  相似文献   
1000.
AIM OF THE STUDY: To compare clinical and ultrasound (US) changes induced in cold thyroid nodules by US-guided percutaneous laser ablation (PLA) versus follow-up or levothyroxine (LT4) suppressive therapy. METHODS: 62 patients randomly assigned to a single PLA (Group 1), LT4 (Group 2), or follow-up (Group 3). Entry criteria: euthyroid patients with a solid thyroid nodule >5 mL and benign cytological findings. TREATMENT: Group 1: PLA was performed with a 1.064 mum neodymium yttrium-aluminum-garnet laser with output power of 3 W for 10 minutes; Group 2: the LT4 dose was adjusted to induce thyrotropin suppression; Group 3: no treatment. RESULTS: In Group 1 a significant nodule reduction was found 6 and 12 months after PLA (delta volume: -42.7 +/- 13.6%; p = 0.001). A reduction >50% was found in 33.3% of cases. In Group 2 a nonsignificant nodule shrinkage was observed. A nonsignificant volume increase was observed in Group 3. Improvement of local symptoms was registered in 81.2% of patients in Group 1 vs. 13.3% in Group 2 and 0.0% in Group 3 ( p = 0.001). No complications were noted. CONCLUSIONS: A single PLA induced significant volume reduction and improvement of local symptoms. PLA was more effective than LT4. Follow-up was associated with nodule growth and progression of local symptoms. PLA should be considered a potential mini-invasive alternative to surgery in symptomatic patients with benign cold thyroid nodules.  相似文献   
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