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41.
背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。  相似文献   
42.
Dopaminergic hyperfunction and N-methyl-D-aspartate receptor (NMDAR) hypofunction have both been implicated in psychosis. Dopamine-releasing drugs and NMDAR antagonists replicate symptoms associated with psychosis in healthy humans and exacerbate symptoms in patients with schizophrenia. Though hippocampal dysfunction contributes to psychosis, the impact of NMDAR hypofunction on hippocampal plasticity remains poorly understood. Here, we used an NMDAR antagonist rodent model of psychosis to investigate hippocampal long-term potentiation (LTP). We found that single systemic NMDAR antagonism results in a region-specific, presynaptic LTP at hippocampal CA1-subiculum synapses that is induced by activation of D1/D5 dopamine receptors and modulated by L-type voltage-gated Ca2+ channels. Thereby, our findings may provide a cellular mechanism how NMDAR antagonism can lead to an enhanced hippocampal output causing activation of the hippocampus-ventral tegmental area-loop and overdrive of the dopamine system.  相似文献   
43.
This analysis was performed to determine the effect of initial therapy on the outcomes of thyroid cancer patients. The study setting was a prospectively followed multi-institutional registry. Patients were stratified as low risk (stages I and II) or high risk (stages III and IV). Treatments employed included near-total thyroidectomy, administration of radioactive iodine, and thyroid hormone suppression therapy. Outcome measures were overall survival, disease-specific survival, and disease-free survival. Near-total thyroidectomy, radioactive iodine, and aggressive thyroid hormone suppression therapy were each independently associated with longer overall survival in high-risk patients. Near-total thyroidectomy followed by radioactive iodine therapy, and moderate thyroid hormone suppression therapy, both predicted improved overall survival in stage II patients. No treatment modality, including lack of radioactive iodine, was associated with altered survival in stage I patients. Based on our overall survival data, we confirm that near-total thyroidectomy is indicated in high-risk patients. We also conclude that radioactive iodine therapy is beneficial for stage II, III, and IV patients. Importantly, we show for the first time that superior outcomes are associated with aggressive thyroid hormone suppression therapy in high-risk patients, but are achieved with modest suppression in stage II patients. We were unable to show any impact, positive or negative, of specific therapies in stage I patients.  相似文献   
44.
Summary Nutritional status was studied over a period of 13 months in 34 patients with rheumatoid arthritis (RA). Seventeen patients fasted for 7–10 days, were then transferred to a gluten-free vegan diet for 3.5 months and finally to a lactovegetarian diet for 9 months. The remaining 17 patients followed a normal diet. After one month, the values for body mass index (BMI) and triceps skinfold thickness (TSF) were significantly reduced in the diet group compared with the values at inclusion (p<0.001), whereas upper arm muscle area (UAMA) was not significantly reduced. Evaluation of the whole study course revealed a significantly lower BMI (p=0.04) and TSF (p<0.01) in the diet group compared with the control group. The concentration of insulin-like growth factor 1 (IGF1) was significantly reduced in the diet group after one month compared with the value at inclusion (p=0.01), but the overall difference between the two groups was not significant. There were no overall significant differences with regard to VAMA, concentration of serum albumin, haemoglobin, ferritin, zinc and copper between the two groups. Thus fast, followed by diet manipulations for one year, had a minor impact on nutritional status in patients with RA.  相似文献   
45.
Summary We have recently reported that fetal BD IX-rat brain cells (FBC), transferred to long-term culture after a transplacental pulse of EtNU on the 18th day of gestation, undergo neoplastic transformation in vitro (BT-cell lines). Tumors developed upon s.c. reimplantation of BT-cells into baby BD IX-rats, appeared histologically as neurinoma-, glioma- or glioblastoma-like, and frequently as pleiomorphic neoplasms. In spite of a more atypic cellular morphology, these tumors grossly resembled the different types of neuroectodermal rat neoplasms induced by EtNU in vivo. Like the neoplastic cell culture lines derived from EtNU-induced, neuroectodermal BD IX-rat tumors (V-cell lines), the BT-lines contained multipolar glia-like cells, but also flat cells with fewer and shorter cytoplasmic processes, and occasionally giant cells. Both the V- and BT-lines showed different levels of aneuploidy. They contained multiple subpopulations of cells, as reflected, e.g., by plurimodal pulse-cytophotometric DNA distributions. All lines contained, to varying degrees, the nervous system specific protein S-100, a marker not yet expressed in FBC. There was no indication of more than borderline neurotransmitter activity, suggesting that proliferating (precursor) cells of glial lineages may preferentially undergo malignant transformation after exposure to EtNU during this stage of brain development.
Zusammenfassung Gehirnzellen der fetalen (18. Tag der Gravidität) BD-IX-Ratte, nach einem transplacentaren N-Äthyl-N-Nitrosoharnstoff (ÄNH)-Puls in vivo in ein Langzeit-Zellkultursystem überführt, durchlaufen den Prozeß der neoplastischen Transformation in vitro (BT-Zellinien). Die nach s.c. Rückimplantation von BT-Zellen in neugeborene BD IX-Ratten entstandenen Tumoren (histologisch vom Neurinom-, Gliomoder Glioblastomtyp, häufig auch pleomorph) waren insgesamt den verschiedenen Arten neuroectodermaler Neoplasmen vergleichbar, die bei BD IX-Ratten nach ÄNH-Applikation in vivo beobachtet werden. Ebenso wie Zellkultur-Linien (V-Zellinien), die von ÄNH-induzierten Tumoren des Nervensystems der BD IX-Ratte abgeleitet wurden, enthielten die BT-Linien multipolare, gliaähnliche Zellen, neben wenigen Riesenzellen aber auch flache Zellen mit vergleichsweise wenigen, kürzeren cytoplasmatischen Fortsätzen. Die V- und BT-Linien waren verschiedengradig aneuploid und aus multiplen Subpopulationen von Zellen zusammengesetzt, widergespiegelt u.a. durch plurimodale impulscytophotometrische DNS-Verteilungen. Alle Linien enthielten das vorwiegend gliaspezifische Marker-Protein S-100, welches im fetalen Gehirn noch nicht exprimiert ist. Eine nennenswerte Neurotransmitter-Aktivität wurde nicht gefunden. Nach Applikation von ÄNH während der perinatalen Phase der Gehirnentwicklung werden offenbar vorwiegend proliferative Zellen glialer (Vorläufer-) Populationen neoplastisch transformiert.

Abbreviations EtNU N-ethyl-N-nitrosourea - i.V. intravenous - s.c. subcutaneous - FBC fetal BD IX-rat brain cells - PBS phosphate buffered saline - BSA bovine serum albumin This is communication No. 14 on a research program devoted to molecular and cellular mechanisms in pulse-carcinogenesis by N-ethyl-N-nitrosourea in the rat nervous systemResearch supported by the Deutsche Forschungsgemeinschaft (Ra 119/5-6; SFB 51/E-13), the C. Bohnewand-Foundation and by the Norwegian Cancer SocietyOn leave from the Institute of Pathology, Sect. B., University of Oslo, Rikshospitalet, Oslo 1, Norway.  相似文献   
46.
Nash  GB; Johnson  CS; Meiselman  HJ 《Blood》1986,67(1):110-118
Although the rheological behavior of sickle cell suspensions and of hemoglobin S solutions is known to be strongly dependent on oxygen tension (PO2), little data exist concerning the influence of PO2 on the viscoelasticity of individual HbSS RBC. We have used micropipette aspiration techniques to test the deformation response of both HbSS and control HbAA RBC over a wide range of PO2 at 23 degrees C. Sickled, spiculed HbSS cells were present for PO2 approximately less than 35 mm Hg; for a number of these cells, the deformation response was essentially elastic and an effective membrane rigidity (EMR) was calculated. EMR increased with decreasing PO2 and was approximately 5 to 50 times higher than the equivalent rigidity of oxygenated HbSS RBC. In addition, the rate of membrane deformation was very slow for sickled cells; the half-time for the deformation process increased as PO2 was lowered and was about two orders of magnitude longer than the equivalent time for normal RBC. Other sickled cells exhibited plastic deformation when subjected to comparable deforming forces and experienced irreversible membrane deformation and budding. At all PO2 levels tested, some HbSS RBC remained as discocytes; these cells had normal membrane elasticity and membrane viscosity. Furthermore, changes in PO2 did not affect the membrane properties of HbAA RBC. Thus, gross abnormalities in the deformation response of HbSS RBC were only detected after morphological sickling had occurred. These abnormalities most likely arose from changes in the cytoplasmic HbS viscoelasticity and, if present in vivo, would be expected to impair the flow of HbSS cells in the microcirculation.  相似文献   
47.
Ehninger  G; Schuler  U; Renner  U; Ehrsam  M; Zeller  KP; Blanz  J; Storb  R; Deeg  HJ 《Blood》1995,85(11):3247-3249
In a canine model we investigated the toxicity and pharmacokinetics of a water soluble busulfan preparation. Busulfan was dissolved in dimethylsulfoxide (DMSO) and administered either orally or intravenously in a single dose of 1 mg/kg. The application in either preparation was well tolerated. In seven dogs, peak levels in the range of 730 ng/mL to 1,000 ng/mL were measured after intravenous injection with an area under curve (AUC) of 75 ng.h/kg.mL to 146 ng.h/kg.mL. It was of note that even the oral administration of the same busulfan preparation resulted in AUC values in the same range as observed after parenteral application. The absorption rate of busulfan tablets in our model was as unpredictable as documented in clinical trials. On the basis of the present study, clinical trials using busulfan dissolved in DMSO given either intravenously or orally appear warranted. This approach should lead to predictable blood levels, reduced toxicity, and increased efficacy of busulfan-containing regimens.  相似文献   
48.
CD40 was originally described as a B-cell-restricted antigen and was subsequently found to be a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 is also expressed on dendritic cells, thymic epithelium, monocytes, and some carcinoma cell lines, and plays a critical role in cell contact-dependent activation. Primary and cultured Hodgkin and Reed-Sternberg (H-RS) cells, the presumed malignant cells of Hodgkin's disease (HD); were found to express high levels of cell surface CD40. We found that recombinant CD40 ligand (CD40L) induced interleukin-8 (IL-8) secretion and enhanced IL-6, TNF, and lymphotoxin-alpha (LT-alpha/TNF-beta) release from cultured H-RS cells. These cytokines play a significant role in the clinical presentation and pathology of HD, a tumor of cytokine-producing cells. CD40L had no mitogenic activity for HD-derived cell lines. In contrast, CD40L enhanced expression of costimulatory molecules intracellular adhesion molecule-T and B7-1 on cultured H-RS cells, both of which are overexpressed on primary H-RS cells. In addition, CD40L induced a 40% to 60% reduction of the expression of the HD-associated CD30 antigen, another member of the TNF receptor superfamily. Primary and cultured H- RS cells express not only CD30, but also CD40. CD40L has pleiotropic biologic activities on H-RS cells, and the CD40-CD40L interaction might be a critical element in the deregulated cytokine network and cell contact-dependent activation cascade typical for HD.  相似文献   
49.
Members of the platelet-derived growth factor (PDGF) ligand family are known to play important roles in wound healing and fibrotic disease. We show that both transient and stable expression of PDGF-C results in the development of liver fibrosis consisting of the deposition of collagen in a pericellular and perivenular pattern that resembles human alcoholic and nonalcoholic fatty liver disease. Fibrosis in PDGF-C transgenic mice, as demonstrated by staining and hydroxyproline content, is preceded by activation and proliferation of hepatic stellate cells, as shown by collagen, alpha-smooth muscle actin and glial fibrillary acidic protein staining and between 8 and 12 months of age is followed by the development of liver adenomas and hepatocellular carcinomas. The hepatic expression of a number of known profibrotic genes, including type beta1 TGF, PDGF receptors alpha and beta, and tissue inhibitors of matrix metalloproteinases-1 and -2, increased by 4 weeks of age. Increased PDGF receptor alpha and beta protein levels were associated with activation of extracellular regulated kinase-1 and -2 and protein kinase B. At 9 months of age, PDGF-C transgenic mice had enlarged livers associated with increased fibrosis, steatosis, cell dysplasia, and hepatocellular carcinomas. These studies indicate that hepatic expression of PDGF-C induces a number of profibrotic pathways, suggesting that this growth factor may act as an initiator of fibrosis. Moreover, PDGF-C transgenic mice represent a unique model for the study of hepatic fibrosis progressing to tumorigenesis.  相似文献   
50.
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