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991.
The occurrence of pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 29-32 kd insulin-like growth factor binding protein, now termed type 1 or IGF-bp1, has been examined in the human ovary by monoclonal and polyclonal antibody based radioimmunoassay and immunohistological techniques. Follicular fluids aspirated from 51 follicles of 32 women undergoing hyperstimulation involving buserelin or clomiphene-based protocols contained 35.5-276.0 ng/ml (mean 101.0 mg/ml) of immunoreactive IGF-bp1. Mean fluid concentrations were three times the level of IGF-bp1 detected in paired serum samples, available for 21 women. Immunoreactive IGF-bp1 in follicular fluid exhibited similar dose-response curves to purified protein and amniotic fluid and immunoreactive IGF-bp1 coeluted in gel filtration with a peak of [125I]-IGF-1 binding corresponding to the elution profile of purified IGF-bp1. Gel filtration also revealed the presence in follicular fluid of a greater than 100 kd binding protein with a binding capacity equal to IGF-bp1 under the conditions employed. A highly significant correlation (P less than 0.001) was found between follicular fluid progesterone and IGF-bp1 and a correlation of lower significance was found between oestradiol and IGF-bp1 (P less than 0.05). However, only low levels of immunoreactive IGF-bp1 were detected in supernatant media of granulosa cells in culture (range undetectable to 2.3 ng/ml). Employing monoclonal antibody-based immunohistology, immunoreactive IGF-bp1 was consistently associated with luteinized granulosa cells of corpora lutea rather than paraluteal cells and its intensity of reactivity appeared to reflect luteal phase steroid hormone profiles. No consistent reactivity was detected in preovulatory follicles and granulosa cells in culture, although reactivity was associated with primordial oocytes. Immunoreactive IGF-bp1 was detected in six of nine supernatant media of explants of luteal tissue obtained from five corpora lutea, with levels ranging from undetectable to greater than 200 ng/ml. These observations suggest that IGF-bp1 is primarily related to luteinization of the granulosa and the resultant luteal cells, and if produced by the luteal cells, additional exogenous factors are required to induce production by granulosa cells in vitro.  相似文献   
992.
红细胞变形性的影响因素及测量方法   总被引:5,自引:0,他引:5  
红细胞的变形能力是一种重要的流变现象,是影响血液循环的主要因素,具有重要的生理学意义。红细胞的变形能力是某些疾病的重要特征。本文从内部因素、外部因素和其他因素三个方面,介绍了小同因素对红细胞变形性的影响,并比较、讨论了测量红细胞变形性的主要方法。  相似文献   
993.
Single-nucleotide polymorphisms (SNPs) within the genes of factor V (FV) (G1691A; exon 10), prothrombin (FII) (G20210A; 3'untranslated - region) and methylenetetrahydrofolate reductase (MTHFR) (C677T; exon 4) are associated with hypercoagulability, and systematic screening of individuals being at higher risk of thrombosis has been suggested. SNPs in the 2q33 region within the genes of CD28 (+17T/C; intron 3) and CTLA4 (-318C/T; promoter and +49A/G; exon 1) are likely to affect T-cell proliferation and antigen presentation signaling, which may lead to altered sensitivity of allograft or self-tissue recognition and affect the incidence of autoimmune diseases. We developed primers that allow specific amplification of these six SNPs at test conditions identical with those used for HLA typing with the CTS PCR-SSP reagents. One hundred ninety-six healthy German Caucasian individuals were tested for the six SNPs. The genotype frequencies for all SNPs were in Hardy-Weinberg equilibrium. There was no significant difference in the distribution of genotypes when compared to other published studies in which these SNPs were tested. The described PCR-SSP method can be used to screen large numbers of patients for these SNPs.  相似文献   
994.
大学生网络成瘾影响因素分析   总被引:5,自引:0,他引:5  
目的探讨大学生网络成瘾的原因。方法采用中文网络成瘾量表、自尊量表、孤独量表、大学生日常生活压力调查表、自编大学生网络使用行为调查问卷,对1450名大学生进行了调查,回收有效问卷1038份。结果对大学生网络成瘾的现状、网络使用特征及心理特征进行调查,建立大学生网络成瘾影响因素模型。结论①大学生网络成瘾呈轻度、重度两种水平,这两种水平总流行率达到14.84%;②网络使用时间、娱乐上网、交易上网、人际上网与网络成瘾存在着显著正相关关系;③自尊、孤独、大学生日常生活压力对网络成瘾有很好的预测作用;④网络成瘾是特定的个体心理特征与特定的网络使用行为、外部环境交互作用的结果。  相似文献   
995.
Cachexia is one of the prominent features of advanced tuberculosis (TB) seen in association with increased expression of the monokine TNF-alpha. Several mycobacterial proteins, including PPD, stimulate TNF-alpha secretion from monocytes. Host factors that may play a role in cytokine expression from monocytes remain largely unknown. One such factor is the opsonizing antibodies. Monocytes have high-affinity receptors (FcgammaI and FcgammaIII) for IgG1 and IgG3 antibodies that mediate antigen uptake. We have reported selective up-regulation of IgG1 (which bind to Fcgamma receptors) in advanced TB and have recently shown the ability of PPD-specific IgG1 antibodies to augment TNF-alpha expression in PPD-stimulated monocytes. These observations have now been extended to other cytokines with semipurified fractions from secreted antigens of Mycobacterium tuberculosis (containing 30 kD and 58 kD) that were devoid of lipids, glycolipids and carbohydrates. In the presence of heat-inactivated TB plasma containing known amounts of antigen-specific IgG1 antibodies, these fractions induced significantly increased TNF-alpha, IL-6 and IL-10 secretion. Absorption of IgG1 with Protein 'A' removed the augmenting activity for TNF-alpha and IL-6 secretion from the TB plasma samples. In the case of IL-10, removal of IgG1 resulted in increased rather than decreased IL-10 secretion. These results suggest a possible pathogenic role for antibodies in TB by enhancing proinflammatory and blocking down-regulatory cytokines such as IL-10 cytokines during the chronic phase of TB.  相似文献   
996.
rhTGF-β1及转染TGF-β1基因对兔角膜内皮细胞增殖的影响   总被引:1,自引:4,他引:1  
目的: 探讨不同浓度的重组人转化生长因子-β1(rhTGF-β1)及TGF-β1基因转染对体外培养兔角膜内皮细胞增殖的影响。方法: 用MTT法检测不同浓度rhTGF-β1作用下角膜内皮细胞的增殖。用脂质体介导转染方法,将TGF-β1基因转移入培养的兔角膜内皮细胞,HE染色法观察细胞组织形态学变化;ELISA法检测转染细胞培养上清中TGF-β1表达量;流式细胞仪检测细胞生长周期变化;DNA电泳法检测转染细胞凋亡情况。结果: MTT检测示5-20 μg/L rhTGF-β1抑制角膜内皮细胞增殖;0.5-1 μg/L组对增殖无影响;0.05~0.1 μg/L组促进细胞增殖。TGF-β1基因转染细胞形态无明显异常,细胞培养上清中TGF-β1的浓度约为(98±3)ng/L。流式细胞仪检测示,基因转染组S期和G2/M期细胞比例减少、PI值降低,但加入EGF后细胞生长基本正常。DNA电泳检测示基因转染组未见凋亡带。结论: rhTGF-β1对角膜内皮细胞增殖的影响具有剂量依赖性;TGF-β1基因转染影响角膜内皮细胞增殖、但不诱发凋亡,其抑制作用可被外源性EGF拮抗。  相似文献   
997.
Summary The existence of an endogenous natriuretic hormone and ouabain-like factors (OLF) has been postulated for many years. This postulate was based on our original observation that a small M.W. fraction in the serum after acute expansion of the extracellular fluid volume (ECFV) not only exhibited natriuretic activity but also inhibited the Na-K-ATPase enzyme in vitro similar to ouabain. Since then, numerous studies confirmed the presence of OLFs in serum, urine, cerebrospinal fluid, and various organs including the heart and hypothalamus. Some of these OLFs are well-known endogenous compounds, such as free unsaturated fatty acids, which inhibit in vitro transmembranous sodium transport, Na-K-ATPase and3H-ouabain binding to its membrane receptor or crossreact with digoxin antibodies. Chemically yet undefined OLFs of potentially hypothalamic origin were detected in various models of experimental and clinical hypertension and are suggested to play a pathophysiological role especially in salt- and volume-dependent forms of hypertension. Our results show that OLFs isolated from the urine of salt-loaded healthy subjects strongly enhance basal and vasopressin-stimulated release of calcium in vascular smooth muscle cells and platelets similar to the effects we had observed with endothelin. This urine fraction also exhibits natriuretic activity which increases in parallel with sodium intake. Further chromatographic separation and amino acid analysis confirmed the peptidic nature (M.W.<1000) of the natriuretic factor(s). However, the two biological activities, namely natriuretic and ouabain-like activities, reside in distinct and chemically different compounds. In face of the previous discovery of the atrial natriuretic peptides (ANP) it is of special interest that very recent observations strongly suggest a natriuretic factor of non-cardiac origin to play an important role in the natriuresis that follows ECFV expansion. In addition, numerous experimental data point to an interaction between the ANP and OLF systems. They should stimulate once again the final identification of these yet unknown endogenous natriuretic and ouabain-like factors.
Die in dieser übersicht zitierten eigenen Untersuchungen wurden von der Deutschen Forschungsgemeinschaft, Bonn, dem Ministerium für Wissenschaft und Forschung des Landes Nordrhein-Westfalen (FA-2914, FA-8871, IVA6-402-046-87), Düsseldorf, und der Konrad-Adenauer-Stiftung, Bonn, unterstützt  相似文献   
998.
Summary According to several reports of close correlations between pulmonary artery pressure and ANF plasma levels it would be convenient to replace invasive pressure monitoring by ANF determination.Mean pulmonary artery and right atrial pressures and pulmonary artery as well as peripheral venous ANF plasma concentrations were measured in 24 patients before and after coronary angioplasty (PTCA) continuously at rest and during exercise: At rest, both pressure and ANF-values remained unchanged before and after PTCA. At exercise, there was a decrease of mean pulmonary artery pressure (from 41.3±8.6 to 31.5±7.4 mmHg,p<0.001), mean right atrial pressure (from 11.9±3.0 to 9.0±2.3 mmHg,p< 0.001), pulmonary artery (282.5±191.0 to 207.3±157.2 pg/ml,p<0.05) and peripheral venous (112.7±48.0 to 97.1±53.2 pg/ml, n.s.) ANF concentration after PTCA. We found no correlation between PTCA-induced changes of right arterial pressures and ANF concentrations, while changes of pulmonary artery pressures were significantly correlated to changes of peripheral venous (r=0.79,p<0.001) as well as pulmonary artery (r=0.59,p<0.01) ANF concentrations at exercise. In 6 of the 24 patients, however there was an inverse relationship between changes of pulmonary artery pressures and ANF concentrations. — Our data demonstrate a significant correlation between changes of ANF plasma level and pulmonary artery pressure values at exercise after PTCA. In the individual case however invasive pressure monitoring cannot be replaced by determination of ANF plasma levels.

Abkürzungsverzeichnis ANF Atrialer natriuretischer Faktor - PTCA Perkutane transluminale Koronarangioplastie - PPa mittlerer pulmonalarterieller Druck - PPc mittlerer pulmonalcapillärer Druck - PRA mittlerer rechtsatrialer Druck Herrn Prof. Dr. med F. Scheler zum 65. Geburtstag gewidmet  相似文献   
999.
Hypercalcemia in breast cancer   总被引:1,自引:0,他引:1  
Hypercalcemia is relatively frequent in malignancy with or without osteolytic bone metastases. It is thought that neoplastic cells may secrete substances which not only stimulate osteoclastic activity but are also capable of modifying the absorption, excretion, and resorption of calcium and phosphate ions. Since 1987, we have studied 24 breast cancer patients with hypercalcemia (22 with bone metastases and two without). The group of 22 patients with bone metastases were divided into two subgroups. The first consisted of 10 patients with high serum levels of humoral factors, such as parathyroid hormone-related protein (PTHrP), and/or prostaglandin E2 (PGE2) and/or interleukin 1 (IL-1), and high levels of bone markers, such as alkaline phosphatase, bone Gla protein and urinary hydroxyproline. The second subgroup consisted of 12 patients with high levels of bone markers alone. Bone histologic analysis showed an osteoclastic activation surrounding metastatic tumor tissue in six out of 10 patients of the first subgroup, while an evident osteolysis caused by the tumor cells was noted in seven out of 12 patients of the second subgroup. The two patients without bone metastases showed normal biochemistry and bone histologic examination. The authors, having tried to explain the pathogenesis of hypercalcemia, emphasize the importance of humoral factors secreted by tumor cells as a direct or indirect cause of hypercalcemia. The origin of hypercalcemia remains unclear in two patients without bone metastases.  相似文献   
1000.
The aim of this study was to investigate whether corticotropin-releasing factor influences the plasma levels of somatostatin, gastrin or cholecystokinin when administered intracerebroventricularly to rats, and if such an effect could be vagally mediated, and dependent on the animals feeding states. Anaesthetized, freely fed rats were given 5 μl intracerebroventricular injections of corticotropin-releasing factor in four doses; 10 pmol-1.28 nmol. Immediately following death, trunk blood was collected for subsequent peptide analysis with radioimmunoassay (RIA). The three higher doses of corticotropin-releasing factor elevated the plasma levels of somatostatin (P < 0.01) after 20 min but left the plasma levels of gastrin and cholecystokinin unchanged. Intraperitoneal injections of 60 and 320 pmol of corticotropin-releasing factor did not influence the somatostatin levels. Further, intracerebroventricular injections of 60 pmol of corticotropin-releasing factor produced a peak increase in somatostatin after 20 min (P < 0.01). After 60 min the somatostatin levels were still increased (P < 0.05). Gastrin and cholecystokinin remained unaltered at these timepoints. Intracerebroventricular administration of 10 nmol of a-helical corticotropin-releasing factor 9–41 attenuated the basal levels of somatostatin and blocked the corticotropin-releasing factor-induced rise in somatostatin. Bilateral truncal vagotomy, as well as pretreatment with atropine (0.05 mg kg-1, subcutaneously) abolished the effects of corticotropin-releasing factor on somatostatin. In animals which were food-deprived for 24 h, corticotropin-releasing factor did not influence somatostatin, gastrin or cholecystokinin. Pretreatment with cholecystokinin did not potentiate corticotropin-releasing factor-induced somatostatin release in food-deprived rats. These findings suggest that corticotropin-releasing factor acting within the central nervous system may regulate gastrointestinal functions partially through a cholinergic, vagally mediated release of somatostatin in freely fed, but not in food-deprived rats.  相似文献   
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