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The immunoperoxidase-antiperoxidase method (PAP) was combined with immunofluorescence for simultaneous localization of glutamate decarboxylase (GAD)-and somatostatin-like immunoreactivity in rat hippocampal neurons growing in dissociated cell culture. A subpopulation of GAD-immunoreactive neurons additionally exhibited somatostatin-like immunostaining. GAD-negative somatostatin-positive cells could not be observed. It is discussed whether the cultured somatostatin-containing GAD neurons correspond to a certain subclass of basket cells as they occur in situ.  相似文献   
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Several lines of evidence indicate that mammalian fertilization is initiated via a binding process that is dependent upon the recognition of oligosaccharide sequences associated with zona pellucida (ZP) glycoproteins. Here, specific chemical and enzymatic methods were employed to modify human ZP and to test their effects on sperm binding in the hemizona assay system (HZA). Periodate oxidation of human ZP under very mild conditions (10 min, 0 degrees C, 1 mM sodium m- periodate) that attacks only terminal sialic acid resulted in a 30% loss of human sperm binding in the HZA [hemizona index (HZI) = 70.2 +/- 10.9, n = 22; P < 0.05]. Periodate oxidation under mild conditions (1 h, 23 degrees C, 10 mM sodium m-periodate) caused a 40% decrease in binding (HZI = 60.8 +/- 10.3; n = 24; P< 0.01). Treatment of human ZP with neuraminidase caused a substantial increase in sperm binding to human ZP (HZI = 297 +/- 45, n = 22; P < 0.01). These findings indicate that there are sialic acid dependent binding sites coexisting with binding sites that are obscured by sialic acid. To determine the periodate sensitivity of these obscured sites, hemizona were first digested with neuraminidase and subsequently subjected to mild periodate oxidation. The combined enzymatic and chemical treatments caused a 79% decrease in sperm binding compared to control hemizona (HZI = 20.7 +/- 4.4, n = 16; P < 0.001). Human sperm-ZP interaction was also increased by digestion of human ZP with endo-beta-galactosidase (HZI = 710 +/- 232, n = 14; P < 0.01), indicating that potential binding sites for spermatozoa are also obscured by lactosaminoglycan sequences. These studies support a definitive role for the involvement of ZP-associated glycans in the binding of human spermatozoa to oocytes.   相似文献   
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Fasciae are the connective tissue sheath of muscles, tendons and ligaments and are interesting for diagnostic and therapeutic approaches in many medical disciplines. Fasciae are the guiding structures for blood vessels, lymphatic ducts and the innervation of certain muscle groups. The interstice forms complex spaces which act as storage areas for fluids and transport passages for chemical and cellular signal pathways, particularly in connection with the immune system. Numerous ailments of the musculoskeletal system are reflected by changes in the fasciae of the muscle systems affected. Especially in the back and the abdomen but also in the extremities, fasciae are functionally and topographically closely related to tendons and aponeuroses which are connected with other muscle systems. They contain sensory organs which are important for proprioceptive perception and pain perception. These receptors, which are innervated by dorsal spinal ganglia, are probably involved in the control of reflexes of the corresponding muscle groups. Knowledge about these interactions can be helpful for various diagnostic and therapeutic approaches.  相似文献   
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Manometry of the alimentary tract is a valuable and widely used means to evaluate and diagnose the function of the alimentary tract. However, the measurement can be inconvenient due to the invasive method used, and the many factors affecting results. Research on colonic pressure data is even more insufficient. This paper deals with colonic pressure data via an improved method ensuring that pressure data of the whole colon is available. The data is analysed based on the learning vector quantization (LVQ) method. Testing results show that this method distinguishes the normal data and the abnormal data, consistently with the original diagnoses. This method can serve as an assistant diagnosis of colonic motility and contributes to further research on colonic motility based on pressure data.  相似文献   
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Gjerset  GF; Martin  PJ; Counts  RB; Fast  LD; Hansen  JA 《Blood》1984,64(3):715-720
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A.  相似文献   
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Background Acute myocardial infarction (AMI) is a common cause of heart failure (HF), which can develop soon after AMI and may persist or resolve or develop late. HF after an MI is a major source of mortality. The cumulative incidence, prevalence and resolution of HF after MI in different age groups are poorly described. This study describes the natural history of HF after AMI according to age. Methods Patients with AMI during 1998 were identified from hospital records. HF was defined as treatment of symptoms and signs of HF with loop diuretics and was considered to have resolved if loop diuretic therapy could be stopped without recurrence of symptoms. Patients were cate- gorised into those aged 〈 65 years, 65-75 years, and 〉 75 years. Results Of 896 patients, 311,297 and 288 were aged 〈 65, 65-75 and 〉75 years and of whom 24%, 57% and 82% had died respectively by December 2005. Of these deaths, 24 (8%), 68 (23%) and 107 (37%) oc- curred during the index admission, many associated with acute HF. A further 37 (12%), 63 (21%) and 82 (29%) developed HF that persisted until discharge, of whom 15, 44 and 62 subsequently died. After discharge, 53 (24%), 55 (40%) and 37 (47%) patients developed I-IF for the first time, of whom 26%, 62% and 76% subsequently died. Death was preceded by the development of HF in 35 (70%), 93 (91%) and 107 (85%) in aged 〈 65 years, 65-75 years and 〉75 years, respectively. Conclusions The risk of developing HF and of dying after an MI in- creases progressively with age. Regardless of age, most deaths after a MI are preceded by the development of HF.  相似文献   
10.
Gaetani  GF; Kirkman  HN; Mangerini  R; Ferraris  AM 《Blood》1994,84(1):325-330
The catalase within normal, intact human erythrocytes was completely inactivated with amino triazole. The rate of 14CO2 evolution, when the cells were subsequently incubated with 14C-labeled glucose, provided a measure of the rate at which NADPH was being oxidized by the glutathione peroxidase/reductase system for the disposal of H2O2. This rate was determined in control cells and in catalase-inactivated cells while the cells were exposed to H2O2, which was generated at various constant and predetermined rates by glucose oxidase. The results indicated that catalase handles approximately half of the generated H2O2. The glutathione peroxidase/reductase mechanism accounted for the other half. These results are in agreement with our earlier findings on erythrocytes of a subject with a genetic deficiency of catalase. However, an unexpected result with the present approach was the finding that the increased dependence on the glutathione peroxidase/reductase mechanism did not occur until greater than 98% of the catalase had been inactivated. The latter observation indicates that catalase and the glutathione peroxidase/reductase system function intracellularly in a manner very different from that previously ascribed to them. An explanation of the findings requires that the two methods of H2O2 disposal function in a coordinated way, such as a sequential action in which the glutathione peroxidase/reductase system is the rate-limiting step.  相似文献   
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