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朱宝亭  褚云鸿 《药学学报》1990,25(7):490-493
本文观察了[D-Ala6,Pro9-Ethylamide10]-LHRH(LHRH-A)对孕中期大鼠的抗妊娠作用。结果显示:在孕9~11d sc 200μg/d LHRH-A,血浆孕酮水平自第二次给药后明显下降(P<0.05),给药大鼠均流产终止妊娠;LHRH-A的抗妊娠作用可被醋酸甲地孕酮所拮抗;LHRH-A对体外培养的假孕大鼠和孕d 9大鼠黄体细胞分泌孕酮有明显的直接抑制作用。  相似文献   
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The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
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Parental and professional responses to questionnaires evaluating a paediatric disability service are reported and the viability of auditing structural, process, and outcome aspects of clinical practice are discussed. Expectations of waiting time to first appointment (met for only 52% of consumers) illustrate structural issues. Process issues are reflected in consumer reactions to outreach work (for example, 94% of parents and 84% of professionals found this supportive). Outcome measures such as consumer satisfaction with the service (76% of consumers reported being 'very satisfied' and 20% 'fairly satisfied') suggest that service aims are being met. Good concurrence of service aims with consumer needs is indicated by parental reasons for referral (for example, 75% for diagnostic help, 73% for a better understanding of the disorder, 88% for practical help), referrers' reasons (for example, 55% for a second diagnostic opinion, 45% due to lack of local expertise), and reports from most other professionals involved with the case that a similar service was not provided locally.  相似文献   
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Klebsiella pneumoniae is an important nosocomial pathogen causing severe pulmonary infections. The majority of clinical Klebsiella isolates produce a high-molecular-weight capsular polysaccharide (CPS) which is one of the dominant virulence factors. In the present study, we examined the potency of a murine immunoglobulin M monoclonal antibody (MAb) with specificity to Klebsiella type 2 CPS to protect rats against experimental Klebsiella pneumonia. The MAb did not prevent the invasion of virulent bacteria into the interalveolar space. However, the resolution of infection was accelerated in MAb-treated animals. This was demonstrated by (i) less severe weight loss and (ii) markedly reduced inflammatory reactions in the lung. The elimination of bacteria was significantly increased not only in the lungs but also in the livers of antibody-treated rats. This was reflected by reduced levels of circulating, soluble CPS and MAb-bound CPS. A mixture of human MAbs with specificity to CPS of clinically important Klebsiella serotypes may prove to be a useful tool for the prevention or supportive treatment of Klebsiella pneumonia.  相似文献   
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Held KS  Chen BP  Kuziel WA  Rollins BJ  Lane TE 《Virology》2004,329(2):251-260
The CC chemokine ligand 2 (CCL2, monocyte chemoattractant protein-1) is important in coordinating the immune response following microbial infection by regulating T cell polarization as well as leukocyte migration and accumulation within infected tissues. The present study examines the consequences of mouse hepatitis virus (MHV) infection in mice lacking CCL2 (CCL2(-/-)) in order to determine if signaling by this chemokine is relevant in host defense. Intracerebral infection of CCL2(-/-) mice with MHV did not result in increased morbidity or mortality as compared to either wild type or CCR2(-/-) mice and CCL2(-/-) mice cleared replicating virus from the brain. In contrast, CCR2(-/-) mice displayed an impaired ability to clear virus from the brain that was accompanied by a reduction in the numbers of antigen-specific T cells as compared to both CCL2(-/-) and wild-type mice. The paucity in T cell accumulation within the central nervous system (CNS) of MHV-infected CCR2(-/-) mice was not the result of either a deficiency in antigen-presenting cell (APC) accumulation within draining cervical lymph nodes (CLN) or the generation of virus-specific T cells within this compartment. A similar reduction in macrophage infiltration into the CNS was observed in both CCL2(-/-) and CCR2(-/-) mice when compared to wild-type mice, indicating that both CCL2 and CC chemokine receptor 2 (CCR2) contribute to macrophage migration and accumulation within the CNS following MHV infection. Together, these data demonstrate that CCR2, but not CCL2, is important in host defense following viral infection of the CNS, and CCR2 ligand(s), other than CCL2, participates in generating a protective response.  相似文献   
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Summary After 3H-lysine was applied to the Xth and XIIth cranial nuclei, radioactive protein synthesized in the nerve cell bodies of the hypoglossal and vagus nerves moved down the axons of these fibers at maximal rates of 6.3±1.2 and 16±3 mm per day, respectively. The distribution of radiolabeled protein at various periods indicated that other proteinaceous components moved at slower velocities.  相似文献   
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Zusammenfassung 1. Bei 24 Kranken mit chronischer Niereninsuffizienz und Urämie wurden die Hirndurchblutungsgröße quantitativ mit der Stickoxydulmethode und der cerebrale Stoffwechsel mit enzymatischen Methoden untersucht.2. Bei einem Harnstoff-N von 142 mg-% und einem arteriellen pH von 7,31 lag die Hirndurchblutungsgröße mit 63,0 ml/100 g · min gering über der Norm. Der cerebrale O2-Verbrauch (2,77 ml/100 g · min) und der cerebrale Glucoseverbrauch (3,75 mg/100 g · min) waren stark vermindert. Der Glucose-Oxydationsquotient war mit 1,13 gering reduziert. Die cerebrale Lactat- und Pyruvatabgabe unterschieden sich nicht sicher von der Norm. Der respiratorische Quotient lag mit 0,89 tiefer als normal.3. Die Aufschlüsselung des Materials in acidotische (pH<7,35) und nichtacidotische (pH>7,35) Urämien ergab unterschiedliche Resultate:a) Bei 15 acidotischen Urämien war die Hirndurchblutungsgröße mit 69,0 ml/100 g · min erhöht. Die Korrelationsberechnung zeigt, daß eine gesicherte negative Beziehung zwischen pH und Hirndurchblutungsgröße besteht: Je stärker die Acidose, desto höher die Durchblutung.Die cerebrale O2-Aufnahme war mit 2,62 ml/100 g · min und die Glucoseaufnahme mit 3,33 mg/100 g · min signifikant vermindert. Der Glucose-Oxydationsquotient war mit 0,98 sehr stark reduziert.b) Bei 9 nichtacidotischen Urämien lag die Hirndurchblutung mit 52,9 ml/100 g · min im Normbereich, während der O2-Verbrauch mit 2,96 ml/100 g · min und der Glucoseverbrauch mit 4,52 mg/100 g · min reduziert waren. Der Glucoseverbrauch war deutlich weniger vermindert als bei den acidotischen Urämien. Daher unterscheidet sich in dieser Gruppe der Glucose-Oxydationsquotient nicht signifikant von der Norm.4. Es besteht eine statistisch gesicherte positive Korrelation von pH und O2- bzw. Glucoseverbrauch, d.h. je stärker die Acidose, desto niedriger sind O2- und Glucoseaufnahme. Zur Höhe des Harnstoff-N besteht keine Korrelation.5. Unter der Therapie mit Abfall des Harnstoff-N und Anstieg des pH besserten sich cerebrale O2- und Glucoseaufnahme und normalisierte sich der Glucose-Oxydationsquotient.6. Es besteht eine Beziehung von cerebraler Funktion (Sensorium klar, getrübt, Praecoma, Coma) zu den cerebralen O2- und Glucoseutilisationswerten, nicht hingegen zur Durchblutungsgröße.7. Die urämische Encephalopathie ist Folge einer acidotisch-toxischen Stoffwechseldepression und geht nicht mit einer cerebralen Zirkulationsstörung einher.Meinen akademischen Lehrern Prof. Dr. Dr. G. Bodechtel und Prof. Dr. A. Bernsmeier zu ihren Geburtstagen im März 1972.  相似文献   
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Dermatoglyphic findings were compared in 42 patients (32 females, 10 males) with Congenital Adrenal Hyperplasia (CAH) and 110 normal controls (70 females, 40 males). In CAH males, an excess of whorls (p less than 0.001), an increased total finger ridge count (p less than 0.05), and an increased frequency of patterns in the fourth interdigital area (p less than 0.025) was found. A main line A terminating high in the hypothenar area (p less than 0.05), and a missing c-triradius or an abortive main line C (p less than 0.05) was observed in CAH females. Both sexes displayed an increase in the frequency of small radially directed hypothenar patterns (p less than 0.05) and sydney lines (p less than 0.01).  相似文献   
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