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991.
Zusammenfassung Es wird eine Örtliche Einwirkung des Pituitrins gezeigt, die zu gesteigerter Wasseraufnahme durch das cutane Bindegewebe fÜhrt. Der Grad der Einwirkung des Pituitrins hängt von dem jeweiligen Zustand der Gewebe ab. Diese selbst scheinen unter dem Einflusse der Leber zu stehen. Der Bindegewebeapparat, welcher sich zwischen den kleinen und kleinsten Gefäßen befindet, reguliert den extravasalen FlÜssigkeitsumlauf.Vorgetragen in der Sitzung der Wiener biologischen Gesellschaft am 7. IV. 1930.  相似文献   
992.
Cell-matrix interactions are governed by a distinct set of proteins, with 2 nonintegrin laminin-binding proteins, galectin-1 and galectin-3, providing 1 aspect. The expression patterns of laminin and the 2 galectins and galectin binding sites were quantitatively determined by means of computer-assisted microscopy with the aim of differentiating between 16 leiomyomas and 10 leiomyosarcomas of the uterus. Three quantitative variables were computed for each of the 5 histochemical markers: labeling index, which describes the percentage of tissue area specifically stained by a given marker; mean optical density which reflects the concentration of the marker; and concentrational heterogeneity, which characterizes the degree of heterogeneity of the marker distribution in the tumor tissue areas. The results reveal evident differences in the galectin-3-related parameters in the 2 tumors groups. Whereas the concentration of galectin-3 binding sites was significantly (P = .01) weaker in the leiomyosarcomas than in the leiomyomas, the percentages of tumor tissue expressing galectin-3 (P = .02) and its binding sites (P = .002) were significantly higher in the leiomyosarcomas than in the leiomyomas. Although significantly (P = .02) higher, the concentration of laminin was more heterogeneously distributed (P = .01) in the leiomyosarcomas than in the leiomyomas. In contrast, the levels of expression of galectin-1 and its accessible binding sites remained similar for both the leiomyomas and the leiomyosarcomas. Finally we document how the levels of expression of galectin-3 and its binding sites can be of assistance in reliably differentiating leiomyomas from leiomyosarcomas.  相似文献   
993.
A reciprocal translocation, t(2;5) (p23; q31) was found in healthy individuals through two generations of a family. The balanced aberration resulted in a derivate chromosome 2 in two malformed offspring in the third generation. The family was ascertained through the two unbalanced carriers whose phenotype abnormalities resembled those of two other offspring who died prior to the cytogenetic examination.  相似文献   
994.
It was found that neurohypophysial peptides oxytocin and Lys-vasopressin selectively decreased the high voltage-activated component of the inward Ca-current in voltage-clamped Helix pomatia identified neurons in a dose- and time-dependent manner. This effect was unaffected or further enhanced applying phosphodiesterases inhibitors. It is suggested that suppression of high voltage-activated current was due to the activation of the adenylate cyclase system, likely protein kinase A.  相似文献   
995.
996.
CONTEXT: The differentiation between iron deficiency and a thalassemia syndrome is an important consideration in the investigation of microcytic anemia. OBJECTIVE: An established statistical method was used to demonstrate the importance of considering ethnic background in combination with mean cell volume (MCV) in the investigation of beta-thalassemia trait in a multicultural urban population. DESIGN: Posttest probabilities for beta-thalassemia trait were calculated using likelihood ratios for various microcytic MCV ranges in conjunction with published pretest probabilities for beta-thalassemia trait based on ethnic background. SETTING: Regional hemoglobinopathy laboratory, St Joseph's Hospital, Hamilton, Ontario, Canada. PATIENTS: Patient data were derived from a previously published study. The original study cohort consisted of 789 patients aged 18 years or older who had an MCV less than 80 fL and were referred for routine complete blood count during a 6-month period. MAIN OUTCOME MEASURES: Posttest probabilities. RESULTS: Simplified tables for the determination of posttest probabilities for beta-thalassemia trait in individual patients based on ethnic background and MCV are provided. An algorithm to assist in determining when thalassemia investigations are indicated is presented. CONCLUSIONS: A high index of suspicion based on ethnic background and low MCV can provide increased sensitivity and specificity for the detection of thalassemia trait in centers with multicultural populations similar to the study population.  相似文献   
997.
998.
The coagulation factor V Leiden mutation, leading to resistance to activated protein C (APC), is the most common inherited risk factor for venous thrombosis. In various systemic autoimmune diseases the hypercoagulable state was shown to be associated with the presence of antiphospholipid antibodies (aPL). Our aim was to determine the prevalence of both, Leiden mutation and aPL in autoimmune diseases and their impact on the occurrence of venous thrombosis. The dataset consists of results from 137 patients having Sj?gren's syndrome (n = 50), progressive systemic sclerosis (n = 43) (PSS), undifferentiated connective tissue disease (n = 24) (UCTD) and mixed connective tissue disease (n = 20) (MCTD) with or without venous thromboembolic complications. The Leiden mutation was detected with polymerase chain reaction (PCR), aPL, such as lupus anticoagulant (LA) with screening and confirmatory procedures and others with enzyme linked immunosorbent assay (ELISA). The prevalence of mutation ranged between 8.3% and 18.0% (13.1%). The thromboembolic risk was found to be increased in the presence of aPL. Eight patients (5.84%) (4 heterozygous) experienced thromboembolic events and 3 out of 4 heterozygous showed aPL positivity, too. There were no difference between the frequencies of Leiden mutation in examined systemic autoimmune diseases and unselected populations.  相似文献   
999.
The authors analyzed several cytomorphonuclear parameters related to chromatin distribution and DNA ploidy in typical and atypical carcinoids and in small cell lung cancers. Nuclear measurements and analysis were performed with a SAMBA 200 (TITN, Grenoble, France) cell image processor with software allowing the discrimination of parameters computed on cytospin preparations of Feulgen-stained nuclei extracted from deparaffinized tumor tissues. The authors' results indicate a significant increase in DNA content--assessed by integrated optical density (IOD)--from typical carcinoids to small cell lung carcinomas, with atypical carcinoids showing an intermediate value. Parameters related to hyperchromatism (short and long run length and variance of optical density) also characterize the atypical carcinoids as being intermediate between typical carcinoids and small cell lung cancers. The systematic measurement of these cytomorphonuclear parameters seems to define an objective, reproducible "scale" of differentiation that helps to define the atypical carcinoid and may be of value in establishing cytologic criteria for differential diagnosis.  相似文献   
1000.
A testicular gonadal stromal tumor with Leydig cells and mesenchymal cells resembling to Sertoli cells is presented. At the ultrastructural level most of the tumor cells could only be classified as endocrine differentiated cells. Because of their uncharacteristic organelles no Sertoli cells could be demonstrated by means of electron microscopy. The labelling of fibrillary actin underlines the cellular heterogeneity and the different cellular functional state of the tumor cells. These findings are interpreted as an evidence of a multidirectional differentiation potential of the gonadal stroma mesenchyme. These observations support the classification of these neoplasia as gonadal stromal tumors particularly in light of the clearly visible differentiation. Problems of evaluating the malignant potential of gonadal stromal tumors are also discussed.  相似文献   
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