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21.
用免疫细胞化学PAP法,对成年大白鼠隔-斜带(S-DB)复合体中,含小白蛋白(PV)神经元的分布和形态学进行了研究,并与含胆碱乙酚化酶(ChAT)神经元的观察进行了比较。含PV神经元主要位于内侧隔核(MS)、斜带垂直支(vDB)和斜带水平支(hDB)。PV免疫反应神经元的形状和大小在S-DB复合体的各个核区或同一核区都不相同,表明这些神经元具有多样的形态学特征。在整个S-DB复合体中,含PV和含ChAT神经元的比例,各占PV和ChAT阳性反应细胞总数的47/和53/,在MS、vDB和hDB中,PV免疫反应神经元的比例分别为38%、54%和59.5%,其余为含ChAT的胆碱能神经元。  相似文献   
22.
成人房室束、假腱索和节制索的亚显微构造   总被引:4,自引:0,他引:4  
本文研究了两例成人房室束、假腱索和节制索的亚显微构造。结果表明,在成人房室束、假腱索和节制索中均可见浦肯野细胞,细胞宽而短,肌原纤维和组成肌原纤维的肌丝均较少;核多为一个,核周肌浆中有大量线粒体,核附近偶见高尔基复合体;肌浆中亦见肌浆网、糖原颗粒和溶酶体等。另外在房室束中,还可见一般心肌细胞和介于浦肯野细胞与一般心肌细胞之间的过渡细胞(或称移行细胞)。胶原纤维和毛细血管等分布在几种肌细胞之间。房室束浦肯野细胞的端与端之间有不甚典型的闰盘。相邻并列的过渡细胞之间见两种连接形式:一种是一个过渡细胞的分支与另一个过渡细胞的外侧面形成闰盘样连接;另一种是并列相邻的两个过渡细胞,以短的分支几乎呈直角互相连接。  相似文献   
23.
The cells of origin of a neocortical cholinergic afferent projection have been identified by anterograde and retrograde methods in the rat. Horseradish peroxidase injected into neocortex labelled large, acetylcholinesterase-rich neurons in the ventromedial extremity of the globus pallidus. This same group of neurons underwent retrograde degeneration following cortical ablations. The region in which cell depletion occurred also showed significant decreases in the activities of choline acetyltransferase and acetylcholinesterase. Discrete electrolytic and kainic acid lesions restricted to the medial part of the globus pallidus each resulted in significant depletions of neocortical choline acetyltransferase and acetylcholinesterase. Hemitransections caudal to this cell group did not result in such depletions. Taken together these observations suggest that the acetylcholinesterase-rich neurons lying in the ventromedial extremity of the globus pallidus, as mapped in this study, constitute the origin of a major subcortical cholinergic projection to the neocortex. The utility of acetylcholinesterase histochemistry in animals pretreated with di-isopropylphosphorofluoridate in identifying cholinergic neurons is discussed in the light of this example; specifically, it is proposed that high acetylcholinesterase activity 4–8 h after this pretreatment is a necessary, but not sufficient, criterion for the identification of cholinergic perikarya.The neurons in question appear to be homologous to the nucleus basalis of the substantia innominata of primates, and are thus termed ‘nucleus basalis magnocellularis’ in the rat. No evidence was obtained to support the hypothesis that nucleus of the diagonal band projects to neocortex. However, striking similarities in size and acetylcholinesterase activity were observed among the putative cholinergic perikarya of the nucleus basalis magnocellularis, the nucleus of the diagonal band, and the medial septal nucleus.Kainic acid lesions of the neocortex produced uniform and complete destruction of neuronal perikarya. These lesions decreased neocortical glutamic acid decar?ylase activity, suggesting that there are GABAergic perikarya in the neocortex. However, the same lesions did not affect neocortical choline acetyltransferase. This observation suggests that there are no cholinergic perikarya in the neocortex, a conclusion that is consistent with the absence of intensely acetylcholinesterase-reactive neurons in the neocortex.  相似文献   
24.
The neurochemical identity of ascending putative cholinergic pathways from the rat basal forebrain was investigated employing a method for simultaneously visualizing choline acetyltransferase immunoreactivity and retrogradely transported horseradish peroxidase-conjugated wheatgerm agglutinin. This histochemical procedure revealed three distinct populations of neurons: (1) cells which stained only for choline acetyltransferase immunoreactivity; (2) cells which stained only for retrograde tracer and (3) cells which stained simultaneously for choline acetyltransferase immunoreactivity and retrograde tracer. The results demonstrated that this projection is topographically organized and consists of both cholinergic and noncholinergic components. The relative contribution of each component varied with the telencephalic target area as follows: the olfactory bulb receives a projection from cells of the horizontal limb nucleus, 10-20% of which are cholinergic (Ch3); the hippocampal formation receives afferents from cells of the medial septal and vertical limb nuclei, 35-45% of which are cholinergic (Ch1 and Ch2); and the cortical mantle receives afferents primarily from cells within the substantia innominata-nucleus basalis complex, 80-90% of which are cholinergic (Ch4). The topographical organization of Ch4 projections is not as completely differentiated as we have previously observed in the primate.  相似文献   
25.
R.P. Vertes 《Neuroscience》1984,11(3):651-668
The origins of projections within the medial forebrain bundle from the lower brainstem were examined with the horseradish peroxidase technique. Labeled cells were found in at least 15 lower brainstem nuclei following injections of a conjugate or horseradish peroxidase and wheat germ agglutinin at various levels of the medial forebrain bundle. Dense labeling was observed in the following cell groups (from caudal to rostral): A1 (above the lateral reticular nucleus); A2 (mainly within the nucleus of the solitary tract); a distinct group of cell trailing ventrolaterally from the medial longitudinal fasciculus at the level of the rostral pole of the inferior olive; raphe magnus; nucleus incertus; dorsolateral tegmental nucleus (of Castaldi); locus coeruleus; nucleus subcoeruleus; caudal part of the dorsal (lateral) parabrachial nucleus; and raphe pontis. Distinct but light labeling was seen in raphe pallidus and obscurus, nucleus prepositus hypoglossi, nucleus gigantocellularis pars ventralis, and the ventral (medial) parabrachial nucleus. Sparse labeling was observed throughout the medullary and caudal pontine reticular formation. Several lower brainstem nuclei were found to send strong projections along the medial forebrain bundle to very anterior levels of the forebrain. They were: A1, A2, raphe magnus (rostral part), nucleus incertus, dorsolateral tegmental nucleus, raphe pontis and locus coeruleus. With the exception of the locus coeruleus, attention has only recently been directed to the ascending projections of most of the nuclei mentioned above. Evidence was reviewed indicating that fibers from lower brainstem nuclei with ascending medial forebrain bundle projections distribute to widespread regions of the forebrain.It is concluded from the present findings that several medullary cell groups are capable of exerting a direct effect on the forebrain and that the medial forebrain bundle is the major ascending link between the lower brainstem and the forebrain.  相似文献   
26.
Bariatric surgery is an effective intervention for management of obesity through treating dysregulated appetite and achieving long-term weight loss maintenance. Moreover, significant changes in glucose homeostasis are observed after bariatric surgery including, in some cases, type 2 diabetes remission from the early postoperative period and postprandial hypoglycaemia. Levels of a number of gut hormones are dramatically increased from the early period after Roux-en-Y gastric bypass and sleeve gastrectomy—the two most commonly performed bariatric procedures—and they have been suggested as important mediators of the observed changes in eating behaviour and glucose homeostasis postoperatively. In this review, we summarise the current evidence from human studies on the alterations of gut hormones after bariatric surgery and their impact on clinical outcomes postoperatively. Studies which assess the role of gut hormones after bariatric surgery on food intake, hunger, satiety and glucose homeostasis through octreotide use (a non-specific inhibitor of gut hormone secretion) as well as with exendin 9–39 (a specific glucagon-like peptide-1 receptor antagonist) are reviewed. The potential use of gut hormones as biomarkers of successful outcomes of bariatric surgery is also evaluated.  相似文献   
27.
目的通过总结克氏针钢丝单张力带内固定治疗四肢不稳定性骨折的手术方法与疗效,探讨四肢不稳定性骨折的有效治疗措施.方法对46例髌骨、肱骨外科颈、尺骨鹰嘴、锁骨远端骨折和肩锁关节脱位的患者采用克氏针钢丝单张力带内固定.结果46例患者关节功能完全恢复,无明显后遗症.结论应用克氏针钢丝单张力带内固定技术治疗四肢不稳定性骨折,简单易行,稳定可靠.  相似文献   
28.
Congenital constriction band syndrome has varied clinical presentations ranging from small, incomplete skin deep constriction band to in utero amputation. Pseudarthrosis of underlying bone most commonly tibia has been reported by many authors. We report the first case of congenital pseudarthrosis of the femur with congenital constriction band syndrome. Nine-day-old female presented with the constriction band in the left thigh with open pseudarthrosis of the femur. The left femur had gross recurvatum deformity and the posterior apex of the pseudarthrosis was exposed via skin ulceration. She had an ipsilateral paralytic clubfoot. She was treated with single-stage excision of constriction band and Z-plasty. Spontaneous union of the femur was achieved at 3 months. Procurvatum deformity of the femur improved gradually over 3 years. This happens to be the first and only reported case of congenital pseudarthrosis of the femur with sciatic nerve palsy due to congenital constriction band.  相似文献   
29.
BackgroundThe long-term safety results of the REALIZE (Ethicon Endo-Surgery, Inc., Cincinnati, OH) adjustable gastric band collected in this prospective, multicenter study in patients with morbid obesity are presented.ObjectivesTo determine the reoperation rate, including band revisions, replacements, and explants, resulting from a serious adverse device-related event through years 4 and 5. Various efficacy measures were also assessed as secondary objectives.SettingNine academic and/or private institutions.MethodsThe participating institutions enrolled 303 patients, who were then assessed on an annual basis, with 231 patients completing 5 years of follow-up. The study parameters included reoperation rates, changes in percentage of excess weight loss (%EWL), and changes in body mass index (BMI), as well as parameters of diabetes and dyslipidemia. Quality of life was assessed using the Short Form (SF)-36 and the Impact of Weight on Quality of Life-Lite questionnaires.ResultsThe reoperation rate due to a serious adverse event in this population at 5 years after implantation with the REALIZE gastric band was 8.9%. The most common serious adverse event was band slippage, which affected 6.9% of the study population. The mean %EWL was 35.6% ± 26.84%, and the decrease in mean BMI was ?7.01 ± 5.45 kg/m2 at 5 years. Patients experienced improvements in mean glycated hemoglobin and serum lipid levels, in addition to improvements in the quality of life measures.ConclusionNo new safety concerns were identified during the 5 years of follow-up. Although the results of this study did not meet the predefined safety criteria of 8% or less, the safety profile and long-term effectiveness observed in this study are consistent with those in the current literature.  相似文献   
30.
BackgroundPostbariatric hypoglycemia (PBH) can be a devastating complication for which current therapies are often incompletely effective. More information is needed regarding frequency, incidence, and risk factors for PBH.ObjectivesTo examine hypoglycemia symptoms following Roux-en-Y gastric bypass (RYGB) and laparoscopic adjustable gastric banding (LAGB) and baseline and in-study risk factors.SettingMulticenter, at 10 US hospitals in 6 geographically diverse clinical centers.MethodsA prospective, longitudinal cohort study of adults undergoing RYGB or LAGB as part of clinical care between 2006 and 2009 were recruited and followed until January 31, 2015, with baseline and annual postoperative research assessments. We analyzed baseline prevalence and post-operative incidence and frequency of self-reported hypoglycemia symptoms as well as potential preoperative risk factors.ResultsIn all groups, postoperative prevalence of hypoglycemia symptoms was 38.5%. Symptom prevalence increased postoperatively from 2.8%–36.4% after RYGB in patients without preoperative diabetes (T2D), with similar patterns in prediabetes (4.9%–29.1%). Individuals with T2D had higher baseline hypoglycemia symptoms (28.9%), increasing after RYGB (57.9%). Hypoglycemia symptoms were lower after LAGB, with 39.1% reported hypoglycemia symptoms at only 1 postoperative visit with few (4.0%) having persistent symptoms at 6 or more annual visits. Timing of symptoms was not restricted to the postprandial state. Symptoms of severe hypoglycemia were reported in 2.6–3.6% after RYGB. The dominant risk factor for postoperative symptoms was preoperative symptoms; additionally, baseline selective serotonin (SSRI) and serotonin-norepinephrine (SNRI) reuptake inhibitor use was also associated with increased risk in multivariable analysis. Weight loss and regain were not related to hypoglycemia symptom reporting.ConclusionHypoglycemia symptoms increase over time after RYGB, particularly in patients without diabetes. In a small percentage, symptoms can be persistent or severe and require hospitalization. Preoperative hypoglycemia symptoms and SSRI/SNRI use in RYGB patients without diabetes is associated with increased risk of symptoms.  相似文献   
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