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171.
The ontogeny of the behavioral effects of acute cocaine administration and behavioral sensitization to cocaine in rat pups was investigated. Acute behavior stimulating effects of cocaine were observed in pups as young as 7 postnatal days (PND) old, although they needed a higher dose of cocaine than adult rats to evoke the same motor effects. An adult dose-response curve pattern of stereotypy and locomotion to acute cocaine treatment was observed at PND 21, and of rearing at PND 28. Rats aged PND 7, 14, 21, 28, and 56 received repeated injections of saline or cocaine (15 mg/kg) twice a day for 5 consecutive days. After a 3-week period of abstinence, sensitization to a challenge dose of cocaine was assessed. Cocaine-induced stereotyped behavior was enhanced significantly only in rats in which cocaine pretreatment was initiated on PND 21, 28, and 56, but not earlier on PND 7 and 14. Adult female rats given repeated cocaine injections on PND 56–60 showed significantly greater sensitization than males, but no such sex difference was observed in pups given cocaine repeatedly on PND 21–25 or 28–32. These results show clearly that cocaine-induced behavioral sensitization in rats occurred only when subchronic cocaine administration was commenced on PND 21 or later.  相似文献   
172.
The relative importance of vitamin D deficiency, secondary hyperparathyroidism, nutritional deficiency and low bone mineral density (BMD) as risk factors for hip fracture is not definitely established. In the framework of a case-control study of risk factors for hip fractured, biochemical markers of bone metabolism and nutrition and femoral BMD data were compared in 136 female and 43 male hip fracture patients, 126 female and 44 male age-matched hospitalized controls, and 47 healthy elderly women (8 men). Patients with hip fracture had lower albumin (−10%9 and 25(OH)-vitamin D (25(OH)D; −19%) compared with hospitalized controls, and lower albumin (−28%) and 25(OH)D levels (−52%) compared with the elderly controls. Serum values of IGFBP-3 were also significantly lower (−33%) in hip fracture patients than in community controls. BMD of femoral neck was lower (p < 0.001) in patients than in hospitalized and community controls. In hip fracture patients, parathyroid hormone (PTH) correlated weakly with BMD (neck: r = −0.19, trochanter: r = −0.17; both p < 0.05). When all women were pooled (n = 233), albumin correlated significantly (age-adjusted) with BMD at all sites (neck: r = 0.27, trochanter: r = 0.25; all p < 0.001). Albumin, but not 25(OH)D, also correlated with skinfold thickness (r = 0.19, p < 0.0025) and with body mass index (BMI) (r = 0.14, p < 0.05). Male patients with hip fracture had lower BMD and albumin (both p < 0.001), 25(OH)D (p = 0.02) and IGFBP-3 levels (p <: 0.005) compared with the controls. When male patients and controls were pooled together, albumin, skinfold thickness and BMI were significantly correlated with each other, but not with BMD. IGFBP-3 was highly correlated with albumin (p < 0.0001), 25(OH)D (p < 0.005) and, less significantly, with PTH (p < 0.05), but not with BMI or skinfold thickness. IGFBP-3 was significantly correlated with BMD at all sites (neck: r = 0.27, p < 0.05); trochanter: r = 0.40, p < 0.0005). In conclusion, low albumin and low BMD were both important risk factors for hip fracture. Low serum albumin was the strongest independent variable correlated with hip fractures. In men, IGFBP-3 was correlated with BMD. The femoral BMD depended only weakly on PTH and 25(OH)D, but was correlated at all sites with albumin, a non-specific parameter of nutrition and general health.  相似文献   
173.
Summary Neurofibromatosis is sometimes complicated by impaired renal tubular reabsorption of phosphate, hypophosphatemia, and osteomalacia. Hyperparathyroidism has also been reported in patients with neurofibromatosis. When hypercalcemia and elevated levels of parathyroid hormone are found in osteomalacia, however, it may be difficult to determine if the hyperparathyroidism was primary or tertiary. We describe a patient with neurofibromatosis, hypercalcemic hyperparathyroidism, hypophosphatemic osteomalacia, vitamin D deficiency, and clear-cell hyperplasia of all four parathyroid glands. Serial biomechanical, bone biopsy, and densitometric studies confirmed that treatment with ergocalciferol, calcium, and phosphate supplements significantly improved the osteomalacia but caused increased parathyroid overactivity. After subtotal parathyroidectomy, the parathyroid hormone concentration became normal and the bone mineral content increased at the spine and hip, but inappropriate phosphaturia persisted. The findings indicate that hyperparathyroidism, osteomalacia, and vitamin D deficiency adversely affect each other.  相似文献   
174.
The clinical findings in 26 patients in whom hepatocellular carcinoma (HCC) was detected after the start of interferon (IFN) therapy for chronic hepatitis C were analysed. Histological study before IFN therapy showed that 34.6% of patients were categorized as stage 3 (septal fibrosis with architectural distortion; the 0–4 scale) and 80.8% demonstrated at least some evidence of septal fibrosis or more advanced features. The AFP levels examined before IFN therapy were more than 20 ng/mL in 13 patients (84.6% of those studied). One of 26 patients had a complete response to IFN therapy, while six of 26 patients had only a partial response. HCC was detected within 1 year after the start of IFN therapy in 76.9% of patients. Thus, the possibility of the early occurrence of HCC or its existence at the time of therapy should be seriously considered when IFN therapy is contemplated. Patients with stage 3 or 3–4 histology may already have a small undetectable HCC before IFN therapy. Thus, for this reason, every patient treated with IFN should be examined at short regular intervals for the development of HCC during and after IFN therapy.  相似文献   
175.
110例嗜酸细胞增多性非变应性鼻炎的液氮冷冻治疗山西医学院第二附属医院(030001)牛玉梅,刘学仁按Mggind将常年性鼻炎分为三类:一类常年性变态反应性鼻炎;二类非变态反应性鼻炎伴鼻分泌物嗜酸细胞增多综合征也叫嗜酸细胞增多性非变态反应性鼻炎(Eosinophilicnonalleraicrhinits,ENR);三类自主神经性常年性鼻炎[1]。我们将ENR中找不到致敏物,而与冷热空气有关与情绪无关的110例患者进行了液氮冷冻治疗。临床资料802例常年性鼻炎患者进行皮肤激发试验。437例找出了致敏物,进行特异性过敏诱因脱敏治疗或抗过敏药物治疗。365例试验阳性,其中有135例与冷热空气有关。ll0例行冷冻治疗。1l0例中男50例,女60例;年龄最大65岁,最小16岁。110例均有间歇性的连续喷嚏发作,浆液性或粘液性鼻分泌物增多和鼻粘膜非充血性肿胀引起的堵塞,无因吸入致敏原诱发症状的病史;血清IgE值不升高,特异性皮肤试验结果为阳性;鼻分泌物中嗜酸细胞阳性。方法:先将鼻腔内喷入1%地卡因溶液3次粘膜表面麻醉,用卷好的4厘米长、0.4~0.6厘米粗的棉棒沾上液氮在鼻镜直视下迅速插入鼻腔内。时间约1分钟左右(冷  相似文献   
176.
A total of 103 fragments in the STR D12S391 locus were sequenced. 24 different alleles were found which can be grouped into 12 allelic classes based on the total number of repeats. The structure of this compund STR consists of blocks of (AGAT) and (AGAC) repeats with a consensus structure (AGAT)8–l7 (AGAC)6–10 (AGAT)0–1. Whereas shorter alleles only have (AGAT) repeats, > 225 bp alleles are more complex, having two motifs (AGAT) and (AGAC). Population data showed that this to be a highly polymorphic STR with a heterozygosity of 0.9. This fact together with its simple structure make this STR very suitable for forensic and genetic purposes.  相似文献   
177.
Cyclin D1 in astrocytic tumours: an immunohistochemical study   总被引:1,自引:0,他引:1  
Forty-eight astrocytic tumours were stained immunohistochemically with antibodies to the cell cycle-regulating protein, cyclin D1, and to the proliferation marker MIB1 (Ki-67) using formalin fixed paraffin embedded tissue and a microwave antigen retrieval system. Cases were classified by the WHO system (1993). The labelling indices (LI) for both antibodies were compared with each other and with the tumour type. The mean labelling indices for both antibodies increased with the degree of malignancy, and a significant difference was seen between the pilocytic astrocytoma and diffuse astrocytoma together vs anaplastic astrocytoma and glioblastoma together. However, within each tumour type there was considerable variation in the labelling indices and a clear cut off value could not be demonstrated. There was a strong positive correlation between labelling indices for cyclin D1 and MIB1 in diffuse astrocytoma, but this correlation broke down increasingly in anaplastic astrocytoma and glioblastoma. There was poor correlation between cyclin D1 and MIB1 in pilocytic astrocytoma, a feature which appeared to separate them from the diffuse astrocytoma. Average labelling indices for cyclin D1 were higher than those of MIB1, which suggests that cyclin D1 positive cells represent a pool of cells from which proliferation and hence MIB1 expression can take place. In conclusion, cyclin D1 is overexpressed in astrocytic tumours, more so with increasing grade of malignancy and in a way which approximately correlates with MIB1 expression.  相似文献   
178.
179.
P16、Cyclin D1蛋白表达与胰腺癌生物学行为   总被引:2,自引:2,他引:0  
目的 探讨P16、CyclinD1蛋白表达水平与胰腺癌发生、发展及预后的关系。方法 应用免疫组织化学SP法结合微波抗原修复法对53例原发性胰腺癌和42例胰腺良性病变及正常组织中P16蛋白及CyclinD1蛋白进行检测。结果 胰腺癌组织、胰腺良性病变和正常组织中P16蛋白的阳性率分别为66.04%和87.71%(P<0.05);CyclinD1表达的阳性率分别为52.83%和23.81%(P<0.05),P16及CyclinD1蛋白表达与胰腺癌的组织分化、病理分期及术后生存期密切相关。结论 P16及CyclinD1蛋白在胰腺癌中的表达可判断胰腺癌的预后。  相似文献   
180.
目的:通过研究丙型肝炎病毒高变区1(HCV HVR1)准种复杂性与基因型之间的关系,探讨不同基因型HCV致病性差异的机制.方法:采用C区型特异性引物PCR法进行HCV基因分型,采用单链构象多态性聚合酶链反应法(SSCP法)检测HCV HVR1准种.结果:68例丙型肝炎患者中,Ⅱ型49例(72%),Ⅲ型13例(19%),Ⅱ、Ⅲ混合型6例(9%).Ⅱ型和Ⅱ、Ⅲ混合型HCV感染患者的HCV HVR1准种复杂性(SSCP条带数)明显高于Ⅲ型感染的患者,且与疾病严重程度关系密切.结论:HCV HVR1准种复杂性的差异可能是导致不同基因型HCV致病性差异的因素之一.  相似文献   
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