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71.
The effect of iontophoretically applied cholecystokinin (CCK) on neurons of the neostriatum was studied in rats anaesthetized with urethane. The most frequently observed effect of the sulphated octapeptide (CCK-8S) on striatal neurons was excitation. Spontaneously active neurons responded more often to CCK-8S than quiescent cells. Silent, primarily non-responsive neurons could often be stimulated with CCK-8S using glutamate to induce an ongoing discharge. Thus, 45.8% of the 177 neurons studied changed their discharge rate by more than 30%. Certain CCK receptor antagonists could prevent the effect of CCK-8S, fully or at least partly, in the majority of CCK-responsive neurons. The data suggest that cholecystokinin modulates the firing of active neostriatal neurons via the CCKA or the CCKB receptor type. Furthermore, we compared neuronal responses to glutamate with those recorded during concomitant administration of CCK-8S in order to study the interaction of both transmitters, which may be colocalized in striatal afferents. CCK-8S mainly enhanced the excitatory effect of glutamate on striatal neurons, but in several neurons the response to glutamate was reduced. The CCKB receptor antagonist could prevent CCK-8S from increasing the glutamate-induced activation.  相似文献   
72.
Policy measures to reduce socioeconomic health differences (SEHD)must be preceded by an analysis of the possibilities and desirabilityof a reduction. This paper argues that it is necessary to pursueequality in health, conceived as equal opportunities to achievehealth. This principle is justified as part of the principleof maximizing individual freedom of choice, and requires thateveryone has the opportunity to be as healthy as possible. Bymeans of this principle a distinction can be made between unjust,unavoidable, and acceptable health inequalities. The determinantsof SEHD which lead to inequalities considered unjust must besubject to policy. These are living conditions (physical andsocial environment and health care) and conditions of choice(e.g. the knowledge of an individual about the health risksof a certain behaviour). Even if SEHD are considered inequities,sometimes conflicting interests will make it difficult to proposea health policy to redress these inequities. These are partlythe consequence of the intersectoral character of a policy aimedat equality of opportunities to attain health, in which theimportance of health has to be weighed against other goals.Moreover the impact of such a policy on the individual freechoice has to be critically weighed. Finally in the contextof health care policy, conflicts between the principle of equalityand maximizing health can be expected.  相似文献   
73.
Summary. During the course of sterility treatment semenograms of 271 IVF and 316 insemination patients were carried out by two automated semen analysers. The parameters of these analyses were correlated to pregnancies resulting from the treatment. Semen samples were analysed in the ejaculate and after swim-up preparation. In addition, the swim-up suspension of IVF patients was measured again 18 h after sperm preparation. Patients were divided into three groups: (1) couples who achieved a pregnancy, (2) couples who did not achieve a pregnancy, and (3) IVF patients with no fertilization of the oocytes. Because of large standard deviations in the quality of ejaculates, the results in the IVF group show no significant differences in the semen parameters of husbands of pregnant and non-pregnant women. In contrast husbands of women with no fertilization have a significantly lower sperm motility. After swim-up preparation these differences no longer occur. A further measurement, taken 18 h later, reveals that there are no differences in the sperm parameters between the pregnant and non-pregnant group. However, the semen quality in the group with no fertilization is significantly reduced. The results of the insemination patients are similar to those of the IVF group. Thus, the results from automated sperm analysers cannot replace either the microscopic or biochemical analysis of an ejaculate and, moreover, cannot be used as prognosis for the fertilization capacity of sperms or a following pregnancy.  相似文献   
74.
Abstract. Experimental evidence suggests that jejunal allografts are rejected as rapidly as are ileal grafts, despite their lesser content of lymphoid tissue as an immunologic stimulus. However, it may be possible to postpone the rejection of jejunal grafts more readily than that of ileal grafts by means of immunosuppressive therapy with cyclosporin (CyA). To test this, we used the rat model (BN-LEW) of orthotopic small-bowel transplantation. The proximal third of the small-bowel with one-third of the mesenteric lymph nodes (n= 20), or the distal ileal third with all of the mesenteric lymph nodes (n= 22), or the entire small-bowel (n= 23) was interposed after resection of an equivalent type and length of recipient bowel. CyA (15 mg/kg) was given to all of these rats for 5 days. Three additional control groups were not given CyA. The difference in graft/recipient survival among the groups receiving CyA and among those not on CyA therapy was not statistically significant. Antidonor hemagglutinin titers, the mixed lymphocyte culture (MLC) assay, and histologic examination of the allograft failed to show a mitigated rejection reaction for the recipients of jejunal grafts. The data show that short-term treatment with CyA prolongs graft survival. Equal doses of CyA, however, did not lead to prolonged survival of jejunal grafts or alter the course of rejection in comparison with that for ileal or whole-bowel transplants.  相似文献   
75.
Trenkwalder P, Plaschke M, Aulehner R, Lydtin H. Felodipine or Hydrochlorothiazide/Triamterene for Treatment of' Hypertension in the Elderly: Effects on Blood Pressure, Hypertensive Heart Disease, Metabolic and Hormonal Parameters.

The aim of the study was to compare the antihypertensive efficacy of either felodipine or the diuretic combination hydrochlorothiazide/triamterene in a group (n = 65) of elderly (≥70 years) hypertensives (office blood pressure ≥ 60/95 mmHg) with special regard to ambulatory blood pressure monitoring, hypertensive heart disease and metabolic parameters. This was a randomized, double-blind study with a treatment period of 6 months. Reduction of office and 24-hr ambulatory blood pressure was comparable with both treatment regimens; after 6 months, 18 of 29 patients in the felodipine group (62%) and 20 of 27 patients in the diuretic group (74%; p = 0.4) were controlled. While episodes of ischemic type ST-segment depression were significantly reduced in the felodipine group (from 49 to 9 episodes), there was no significant change in the diuretic group (from 24 to 21 episodes). Both regimens decreased left ventricular wall thickness, but the decline in left ventricular muscle mass index was significant only for felodipine. Felodipine did not induce any change in metabolic or hormonal parameters; the diuretic combination significantly increased serum creatinine, uric acid, plasma renin activity, and plasma prorenin. Thus, the antihypertensive efficacy of felodipine and the diuretic combination was comparable in elderly hypertensives; only felodipine, however, improved parameters of hypertensive heart diesease and showed a neutral metabolic and hormonal profile.  相似文献   
76.
Di(2-ethylhexyl) terephthalate (DEHT) is a commercially produced chemical (Kodaflex® DOTP) that is used as a general purpose, low-volatility plasticizer for polyvinyl chloride and other polymeric materials. Less than 30 million kilograms of DEHT are produced annually. DEHT is isomeric with di(2-ethylhexyl) phthalate (DEHP), a nongenotoxic rodent carcinogen whose mode of action has been suggested to derive from its ability to produce hepatocellular proliferation and/or hepatic peroxisome proliferation. Thus it is important to know the behavior of DEHT in genotoxicity assays in order to compare it with that of DEHP and other phthalate ester plasticizers. It is known from previously published studies that rats fed DEHT in the diet at 2,000 mg/kg produce urine that is negative in the Ames Salmonella bacterial mutagenicity assay in the presence and absence of induced rat liver S-9 and in the presence and obsence of β-glucuronidase/aryl sulfatase. Reported here are the results of direct testing of DEHT in the Ames plate incorporation assay, the Chinese hamster ovary/hypoxanthine guanine phosphoribosyl transferase (CHO/HGPRT) in vitro mammalian cell mutagenicity assay, and an in vitro chromosome aberrations assay using CHO cells. The results for mono(ethylhexyl) terephthalate (MEHT), a metabolite of DEHT, in the Ames Salmonella bacterial mutagenicity assay are also presented. All test results for both DEHT and MEHT were found to be negative, and it is therefore concluded that DEHT, like its isomeric relative DEHP, is not genotoxic. © 1994 Wiley-Liss, Inc.  相似文献   
77.
We report a case of an 81-year-old woman in whom lichenoid eruptions and Sjögren-like sicca syndrome developed 45 days after cholecystectomy. During surgery, one unit (130 ml) of unirradiated packed red blood cells from a male donor was transfused. The lichenoid eruptions cleared up with exfoliation; however, sicca symptoms remained during the follow-up period of four years. Histological examinations of both skin and lip biopsy specimens were in agreement with those of graft-versus-host disease (GVHD). A Y-chromosomal body was identified in the lymphocytes in the skin lesion by staining with quinacrine dihydrochloride and in the lip lesion by a method with in situ hybridization. The findings suggest that this case demonstrated the manifestations of non-fatal transfusion-associated GVHD.  相似文献   
78.
目的:观察老年大鼠不同脑区胆碱能M1亚型受体的变化和黄芪对其的调节作用。方法:采用放射自显影技术显示大鼠脑M1受体,并用图像分析仪进行灰度分析,以反映M1受体在不同脑区的相对定量分布。结果:所得脑切片自显影灰度层次清晰,主要分布在大脑皮质、海马、纹状体部位,非特异结合灰度很低,老年大鼠皮质、海马、纹状体的灰度显著低于青年鼠,分别降低1578%,869%,1236%(P<005),老年服黄芪组三个部位的灰度均明显高于老年对照组,分别升高1663%,981%,1032%,(P<005)。结论:黄芪对老年大鼠降低的脑胆碱能M1亚型受体具有上调作用。  相似文献   
79.
尼氏小体染色方法的改进及其在神经病理学研究中的应用   总被引:6,自引:0,他引:6  
组织或细胞的染色在病理学诊断、科学研究和教学工作中,都具有非常重要的意义和使用价值。组织切片染色的质量好坏对于医学诊断,科研和教学至关重要。为了更好的研究神经组织,使医学诊断、科研和教学工作更为方便,本文对Toluidine Blue(甲苯胺蓝)染色方法做了一些改进。在传统的甲苯胺蓝染色过程中,仅考虑对细胞核和尼氏小体进行染色,未考虑细胞浆和其他细胞器:而改进后的甲苯胺蓝染色方法在甲苯股蓝染色后用伊红再染色,既考虑对细胞核和尼氏小体进行染色,也对细胞浆进行了染色。结果显示传统的Toluidine Blue染色结果光镜下观察,细胞核和尼氏小体都可见,即尼氏小体为深蓝色,细胞核为蓝色,染色背景为淡蓝色;改进后的染色结果光镜下观察,尼氏小体为紫蓝色,细胞核为蓝色,染色背景为粉红色。可见,改进后的染色方法染出的组织切片比传统的要清晰、美观。随着科学技术的飞速发展,病理学的研究也随之发展,病理技术势必进一步提高,来适应科技的进步和医学的发展。改进的尼氏小体染色法能够使脑组织切片更清楚观察,更有利于医学工作者对神经组织及尼氏小体的研究。  相似文献   
80.
低剂量甲基汞在小鼠体内分布及其对细胞周期进程的影响   总被引:3,自引:0,他引:3  
连续90天饮用含甲基汞浓度为1/1000LD50、1/100LD50、1/50LD50和1/10LD50的自来水的雄性昆明小鼠,各脏器中总汞含量均高于对照组(P<0.05~0.005),并且随着染毒剂量增加,脏器中总汞含量也随之增高。同时采用FACScan流式细胞仪和“CellFIT”软件分析脾细胞周期进程,发现除1/1000LD50剂量组外,其余各剂量组从Go/G1时相进入S时相的脾细胞百分数均明显高于对照组(P<0.05),与染毒剂量呈明显正相关。表明连续经口摄入低剂量甲基汞小鼠脾细胞周期进程加快,细胞DNA复制增强。  相似文献   
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