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71.
The sympathetic cardiac nerves originating from the cervical and upper thoracic sympathetic ganglia in the house musk shrew (Suncus murinus) were examined using macroscopic and whole‐mount immunohistochemical methods. Based on the results, the nerves were macroscopically classified into the following three groups: nerves innervating the cervical sympathetic ganglia mainly to the arterial porta of the heart; nerves supplying the stellate and thoracic sympathetic ganglia at the level of T2–T5 or T6 for both the arterial and venous portae of the heart; and nerves innervating the thoracic sympathetic ganglia at the level of T4–T9 to the esophagus and lung and then the heart via the blood vessels within the mediastinal pleura. These findings in the house musk shrew suggest a possible primitive morphological pattern of the cervical and thoracic sympathetic nervous system that may be related to those in other mammals, including humans. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
72.
用免疫组化双标记法研究了29例不同胎龄人胎儿垂体前叶P物质免疫反应阳性神经纤维与促甲状腺素免疫反应阳性细胞的关系。人胎儿垂体前叶存在少量粗细不等的P物质反应神经纤维,多成丛分布于前叶的中央区及其与外侧部的交界区。随着发育,P物质反应纤维增多、增长,分布趋于集中。促甲状腺素反应细胞在早期多有短粗突起,中期增长、增多,晚期又减少;细胞主要位于背腹缘及中央区,晚期较密集。在P物质反应纤维与促甲状腺素反应细胞的分布重叠区域内可有较密切接触,随发育其接触数量及其密切程度均有增加。结果提示人胎儿垂体前叶内P物质反应神经纤维与促甲状腺素反应细胞可能存在功能方面的联系。  相似文献   
73.
The diagnosis of mycobacterial infection depends on the Ziehl-Neelsen (ZN) stain, which detects mycobacteria because of their characteristic acid-fast cell wall composition and structure. The histological diagnosis of tuberculosis (TB) comprises various aspects: (1) sensitive detection of mycobacteria; (2) precise localization of mycobacteria in the context of granulomatous lesions; (3) 'staging' of disease according to mycobacterial spread and granulomatous tissue integrity. Thus, detection of minute numbers of acid-fast bacteria in tissue specimens is critical. The conventional ZN stain fails to identify mycobacteria in numbers less than 10(4) per ml. Hence many infections evade diagnosis. PCR is highly sensitive, but allows neither localization within tissues nor staging of mycobacterial disease, and positive findings frequently do not correlate with disease. In this study, an anti-Mycobacterium bovis bacille Calmette-Guérin polyclonal antiserum (pAbBCG) was used to improve immunostaining, which was compared to the ZN stain in histological samples. Screening of tissue samples including lungs, pleural lesions, lymph nodes, bone marrow, and skin for mycobacterial infection revealed that pAbBCG staining detects infected macrophages harbouring intracellular mycobacteria or mycobacterial material as well as free mycobacteria that are present at low abundance and not detected by the ZN stain. The positive pAbBCG staining results were confirmed either by PCR analysis of microdissected stained tissue or by culture from tissue. This immunostaining approach allows precise localization of the pathogen in infected tissue.  相似文献   
74.
目的 了解杏仁体中多巴胺(DA)能神经末梢和7-氨基丁酸(GABA)能神经元之间的相互关系、探索两者在精神分裂症中作用的神经解剖学机制。方法 用免疫电镜双标技术,分别以抗DA和抗谷氨酸脱羧酶(GAD、GABA的合成酶)标记大鼠杏仁体基底外侧核中DA能神经末梢和GABA能神经元,在电镜下观察DA能神经末梢和GABA能神经元之间的突触联系。结果 由DA免疫阳性神经末梢形成的突触中,有43%直接或间接形成于DA免疫阳性神经末梢与GAD免疫反应阳性树突结构之问,其中单一性突触为38%、汇聚性突触为30%、连续性突触为20%、末梢间突触样联系为12%。另外的57%由DA免疫阳性神经末梢与未标记的神经结构形成,其中在未标记的神经元胞体形成10%、树突上82%、轴突末梢上8%。由DA免疫反应阳性末梢形成的所有突触均为对称性即抑制性突触。结论 在大鼠杏仁体基底外侧核中,DA能神经末梢系统以对称性突触支配着GABA能中间神经元,同时,又与核内的谷氨酸能投射神经元形成突触联系.并影响其活动。  相似文献   
75.
In the septal complex, both parvalbumin and calbindin neurons cocontain GABA. In the same area, a large number of GABA-GABA synaptic connections can be observed. In order to further characterize their neurochemical nature, as well as the extrinsic and/or intrinsic origin of these GABA terminals, the following experiments were performed: (1) correlated light- and electronmicroscopic double immunostaining for calbindin and parvalbumin on septal sections of control rats; (2) light microscopic parvalbumin immunostaining of septal sections after surgical isolation (5 days) of the septum from its telencephalic or (3) hypothalamic afferents; and (4) parvalbumin immunostaining of sections prepared from the entire brain 2 days following horseradish peroxidase injection into the border between the lateral and medial septum. The results demonstrated that: (1) in a well-circumscribed, vertically longitudinal area located between the lateral and medial septum, 0.1–0.6 mm anterior to the bregma, a group of calbindin-containing, nonsomatospiny neurons are surrounded by parvalbumin-immunoreactive baskets; (2) these basket-forming axon terminals establish symmetric synaptic contacts with their targets; and (3) their cells of origin are not in the medial septum, but in the angular porition of the vertical limb. These observations indicate that a portion of the septal complex GABA-GABA synaptic connections represent functional interaction between two different types of GABAergic neurons. The presynaptic GABAergic neurons contain parvalbumin, and the postsynaptic GABAergic cells are immunoreactive for calbindin. Furthermore, a population of the medial septum/diagonal band parvalbumin neurons promect only to the hippocampus, while others, which may also send axons to the hippocampus, terminate on lateral septum calbindin cells as well.  相似文献   
76.
We report the pathologic finding of a multinucleated foreign body giant cell reaction to squames and fetal hair in the placental membranes in a 37-week 1-day intrauterine gestation. This reaction appeared to have developed in association with repeated intrauterine procedures performed in the third trimester, including cordocentesis for fetal blood sampling, intrauterine blood transfusion, and amnioreduction for polyhydramnios. This type of reaction most likely was directed to prolonged amniotic fluid leakage that occurred spontaneously or after intrauterine procedures in the second half of the second trimester and the third trimester. Careful examination of the placental membranes and recognition of the foreign body giant cell reaction may provide etiologic insight in cases of unexplained oligohydramnios.  相似文献   
77.
Terminal deoxynucleotidyl transferase (TdT) is a DNA polymerase located in the cell nucleus which catalyses the polymerization of deoxynucleotides at the 3′ hydroxyl ends of oligo- or polydeoxynucleotide initiators without a template. TdT is known as a useful marker for the diagnosis of acute lymphoblastic leukaemia/lymphoma, but its detection usually requires fresh tissue specimens or cell suspensions, using either an enzyme analysis or immuno-fluorescence or -peroxidase staining. Until the recent development of the use of microwave-treated paraffin sections for immunoperoxidase staining, detection of TdT in paraffin sections required rather complicated processes. This new simple technique was applied to paraffin sections from the tumour tissue specimens of 16 patients with lymphoblastic lymphoma and of seven patients with non-endemic Burkitt's lymphoma, which is sometimes difficult to differentiate from lymphoblastic lymphoma because of their similar clinicopathological characteristics. In addition, as a control, ten cases each were examined of adult T-cell leukaemia/lymphoma (ATLL) and angioimmunoblastic lymphoma (AILD), which are both peripheral T-cell lymphomas. The tumour cells from 15 of the 16 (94 per cent) patients with lymphoblastic lymphoma were found to be TdT-positive. The specificity of the anti-TdT antibody used was confirmed by immunoblot and the specific 60 kD band was detected only in a specimen of lymphoblastic lymphoma. These results show that the immunostaining of TdT on paraffin-embedded sections is a useful method for differentiating lymphoblastic lymphoma from other lymphomas. This method is applicable to a routine diagnostic service. © 1997 John Wiley & Sons, Ltd.  相似文献   
78.
A large number of septal neurons express α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate (AMPA)-type excitatory glutamate receptors. It has been demonstrated that in the mediolateral part of the rat lateral septum, calbindin-containing neurons are heavily innervated by hypothalamic, enkephalinergic fibers forming exclusively asymmetric synaptic contacts. This connection was suggested to be excitatory. In order to further elucidate this hypothesis, the aim of the present study was to determine whether these enkephalinoceptive neurons express GluR1 and GluR2/3 AMPA receptor subunits. Correlated light and electron microscopic analysis, using single immunostaining for GluR1 and GluR2/3, and double immunostaining for Leu-enkephalin and GluR1 or GluR2/3, was performed on vibratome sections of the rat lateral septal area. The studies revealed that while GluR1 is mainly associated with dendritic and somatic spines, GluR2/3 is mostly present in the perisomatic area. Leu-enkephalin boutons establish asymmetric synaptic contacts at the level of the soma and initial dendrites of both of these cells. A semiquantitative analysis showed that these enkephalin-targeted cells represent 50% of the total number of both GluR1 and GluR2/3-containing lateral septal neurons. These results suggest that: (1) AMPA receptor-expressing neurons appear to be the exclusive recipient of hypothalamic Leu-enkephalin boutons; (2) these enkephalinoceptive neurons contain both GluR1 and GluR2/3 AMPA receptor subunits; however, (3) only the GluR2/3 subtype, located in the perisomatic area, may be associated with Leu-enkephalin-containing inputs. Synapse 25:263–271, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
79.
Malignant melanomas are known to present diverse patterns and this can result in considerable difficulties for an interpretation of malignancy type from cytohistologic material. Such difficulties are further compounded, if melanin pigment cannot be demonstrated by conventional histochemical stains; unfortunately many cases do exhibit this feature, especially in its metastases. This study was designed to review cases of amelanotic metastatic malignant melanomas in a variety of cytologic samples which were received from 40 patients with a known history of malignant melanoma. Cytomorphologically, the cases were classified as classical, carcinoma-like, spindle cell type, lymphoma-like, and undifferentiated type (Table I). While in 36 of the cases, the diagnosis of metastases from a melanoma was confirmed based on an immunopositivity to a variety of melanoma markers (Table III), in four of the cases, the immunostaining indicated metastases from another primary source, which was subsequently found. Based on our study, we are of the opinion that an immunologic characterization is useful to conclusively diagnose the majority of cases of metastatic amelanotic malignant melanomas. Furthermore, we feel that a reliance on a single melanoma marker is not justified, and a panel of antibodies should be used to distinguish a metastatic amelanotic malignant melanoma from other metastatic neoplasms. Diagn. Cytopathol. 16:238–241, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
80.
Because follicular thyroid carcinoma is extremely difficult to diagnose, several cases were encountered which have been rediagnosed as carcinoma due to distant metastasis. In the search for a method of correctly diagnosing 'benign' thyroid tumor, dipeptidyl peptidase (DPP) IV immunostaining was applied to 10 cases whose diagnoses had been corrected to follicular thyroid carcinoma because of distant metastases. The positive rate of immunostaining using paraffin sections in the rediagnosed follicular thyroid carcinoma group (7/10) was much higher than that of the control group (1/29), which consisted of 15 cases of follicular thyroid adenoma and 14 cases of nodular hyperplasia. These results suggested that pre- or postoperative DPP IV staining is useful for predicting distant metastasis of 'benign' thyroid tumor.  相似文献   
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