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121.
A surgical case of proliferative funiculitis (pseudosarcomatous myofibroblastic proliferation of the spermatic cord) with a prominent mast cell infiltration is reported. A 67-year-old man with a history of right inguinal herniorrhaphy 7 years earlier was operated on for diffuse swelling of the inguinal region and scrotum. A large lipoma was found in the inguinal region, and a nodular lesion, measuring 2.7 cm in maximal dimension, was firmly attached to the right spermatic cord. The nodular lesion showed diffuse proliferation of fibroblasts and myofibroblasts associated with the deposition of collagen. A diffuse infiltration of numerous mast cells was found throughout the lesion. Lesions that belong to the group of inflammatory pseudotumors are rarely accompanied by a prominent mast cell infiltration, and the differentiation from mast cell neoplasms is often problematic in such cases. The present case is the first example of proliferative funiculitis associated with this rare phenomenon.  相似文献   
122.
The urethral duct and vagina are formed from the urogenital sinus (UGS) during the early neonatal period in mice. Neonatal estrogen exposure results in hypospadias, or the malpositioning of vaginal and urethral openings, with wide cleft clitoris. We sought to characterize diethylstilbestrol (DES) influence on UGS morphogenesis and hypospadias formation. Newborn (day 0) and 1–4‐day‐old female mice (ICR/Jcl) were given (s.c.) oil or 3.0 μg DES. Animals were killed 24 hr later; then hypospadias formation and epithelial apoptosis and proliferation within the developing UGS were assessed. DES did not alter normal UGS morphogenesis by day 1, in comparison with controls. However, hypospadias formation was observed in DES‐treated mice by day 3. In these mice, the distal dorsal urethral duct appeared to fuse with and open into the lower vaginal solid cord region. Further, DES treatment produced a gradual significant increase in dorsal urethral epithelial apoptosis (P < 0.05) just prior to and during fusion and hypospadias formation. DES‐induced urethral epithelial and sinus cord proliferation appeared significantly increased (P < 0.05) and unchanged, respectively, just prior to fusion. By day 5, DES‐treated mice exhibited wide cleft clitoris. In addition, if DES was given on day 3 or 5, a gradual, distinct caudal shift in the vaginal‐urethral junction was observed compared to mice treated on days 0–2. Although hypospadias was not induced when neonates were given DES on day 7, these mice continued to display early vaginal opening. Dose‐response analysis indicated that 0.03 μg DES for 5 days is the lowest known critical dose for hypospadias induction. We have shown for the first time that DES‐induced hypospadias onset may primarily be the result of changes in developing dorsal urethral epithelial cell apoptotic and proliferative activity, and that the location of DES‐induced hypospadias formation is dependent on age at time of exposure. Anat Rec 266:43–50, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
123.
腰骶部SPR术中脊神经前后根定位的应用解剖   总被引:13,自引:6,他引:13  
目的:为SPR提供可靠的术中脊神经前、后根鉴别的解剖学依据。方法:在20例成人脊柱标本上,去除后部结构,暴露整个马尾神经,对L1~S2节段的前后根进行形态学观察和测量。结果:脊神经后根位于马尾的后半部,前根则位于前半部。脊神经后根较相应的前根粗大,后根从L1~S1逐渐增大,以S1为最粗大;前根则以L3最粗大。相应前后根出硬脊膜前,有一段相互贴附并紧贴硬脊膜侧壁。结论:在多椎板切除SPR术中前、后根的定位及鉴别,暴露时可根据前、后根出硬脊膜前的相互贴附;在限制性椎板切除时则可通过脊髓外侧索和L1前、后根之间的最下端的齿状韧带加以鉴别  相似文献   
124.
在手术显微镜下观察了37例婴幼儿脊髓前(正中)动脉和脊髓后(外侧)动脉的分支,其主要结果如下:婴幼儿脊髓平均长度为14.08±1.49cm,脊髓前(正中)动脉外侧分支平均为76.17±18.64支,中央动脉平均为169.78±25.51支.中央动脉分布到灰质前角、侧角和后角底部及邻近灰质的深层白质,而白质浅层和后角大部,则由软膜动脉网发出的穿支供应.此外.还讨论了与临床应用有关的问题.  相似文献   
125.
126.
Summary To better comprehend somatotopic development of the corticospinal projection system, wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was injected into cervical or lumbar enlargement of the spinal cord of postnatal rats. The cervical projecting neurons appeared first in the middle of the lateral surface of the posterior frontal and anterior parietal cortex on the second postnatal day (postnatal day one, P1). By P3, labeled neurons were distributed in the rostral two-thirds of the cortex, with concentrations both on the same cortex as in P1 and on the dorsomedial part of the frontal cortex. Size of the labeled area was gradually reduced between P3 and P12 to attain an adult organization: three discrete clusters of labeled neurons were isolated in the dorsomedial part of the frontal cortex, the middle of the lateral surface of the posterior frontal and anterior parietal cortex, and in the temporal cortex. The lumbar projecting neurons first appeared in the dorsomedial part of the parietal cortex, on P4. Size of the lumbar projecting area increased by P6 and decreased by P12 to attain the pattern seen in adult animals.Our findings suggest that 1) potential pioneer fibers reaching the cervical enlargement originate from the middle of the lateral surface of the posterior frontal and anterior parietal cortex, and those reaching the lumbar enlargement, from the dorsomedial part of the parietal cortex, and 2) transiently projecting areas consist of less densely distributed neurons compared to the areas destined to become the corticospinal projecting area in adult.  相似文献   
127.
 The effects of a protein kinase C (PKC) activator, 12-O-tetradecanoylphorbol-13-acetate (TPA), on the activity and periaqueductal gray (PAG)-induced inhibition of rat dorsal horn neurons of the lumbar spinal cord were tested. A microdialysis fiber was placed through the dorsal horn for the purpose of local application of pharmacological agents. Extracellular single-unit recordings from dorsal horn neurons were made near the microdialysis fiber. TPA was tested on nociceptive dorsal horn cells. There was a significant increase in the background activity and responses to ”brush”, with no changes in responses to pressure and pinch stimuli. TPA also significantly blocked the PAG-induced inhibition of responses to brush, press, and pinch. These effects were eliminated by coadministration of the PKC inhibitor NPC-15437. The solvent, which contained dimethyl sulfoxide, was also tested for its effect on the responses to peripheral mechanical stimuli and PAG-induced inhibition of the dorsal horn neurons. There were no significant changes. This experiment suggests that activation of the PKC second messenger system might increase the activity of dorsal horn neurons and their responses to peripheral stimuli; in addition, the phorbol ester attenuated the PAG-induced descending inhibition of the dorsal horn neuron activity. Received: 15 May 1996 / Accepted: 14 November 1996  相似文献   
128.
Summary The patterns of regional changes of sympathetic efferent activity evoked by thermal stimulation of the spinal cord and by arterial and primary tissue hypoxia were investigated in decerebrated, anesthetized and immobilized rabbits. Decerebration was performed either at the mid- or infracollicular level. The responses of the decerebrated rabbits evoked by spinal thermal stimulation were the same as those of intact rabbits, i.e., splanchnic and cardiac sympathetic activity increased and cutaneous sympathetic activity decreased during warming, while the reverse response was elicited by cooling. It is concluded that the typical thermoregulatory response pattern of the sympathetic nervous system can be produced also after the loss of hypothalamic integration, i.e., by integrative mechanisms in the lower brain stem and the spinal cord. In contrast, the responses of decerebrated rabbits to arterial and primary tissue hypoxia differed from those of intact rabbits in that they consisted in an overall activation in all investigated sympathetic branches. It is confirmed by this result that suprabulbar integration is essential for the generation of the inhibitory components in the differential sympathetic responses to hypoxia, which typically consist in cutaneous and cardiac sympathetic inhibition with splanchnic activation during arterial hypoxia and in cutaneous sympathetic inhibition with cardiac and splanchnic sympathetic activation during primary tissue hypoxia.  相似文献   
129.
目的:探讨小陷胸汤加味中药方对血管内皮细胞的保护作用。方港:建立ox-LDL损伤人脐静脉内皮细胞株(ECV-304)模型,用小陷胸汤加味含药血清处理模型,并用放免和硝酸酶还原法在药物干预6h和24h后检测细胞上清液中ET-1和NO含量。结果:100 μg/ml的ox-LDL可损伤血管内皮细胞并导致其分泌NO和ET-1功能失调,小陷胸汤加味含药血清通过影响NO/ET-1的分泌而明显改善此失调状态。结论:小陷胸汤加味中药通过调节NO/ET-1水平显著拮抗ox-LDL对血管内皮细胞损害,具有防治AS的作用。  相似文献   
130.
大鼠延髓网状背侧亚核下行投射终末在脊髓灰质的分布   总被引:5,自引:1,他引:5  
本研究应用PHA-L顺行追踪技术研究了大风延髓网状背测亚核(SRD)至脊髓灰质下行投射的终止部位。结果表明:SRD发出的下行纤维走行于脊髓的背外侧京中,从高位至低位,脊髓灰质中的PHA-L顺标终末的密度逐渐降低。SRD的下行投射终未在脊髓中具有明显的同侧分布优势,主要终止在同侧脊历灰质的Ⅳ~Ⅶ层和X层,Ⅰ、Ⅱ层中只有少量的标记终末,对侧脊髓灰质中除了在Ⅳ层和X层中有中等密度的颁标终末分布外,其余各层中几乎无标记终未、PHA-L顺标终未与BSI-B4标记的初级传入C纤维终末在Ⅰ.Ⅱ层内重叠公布.本研究为SRD在调控脊髓的伤害性信息传递方面也起重要作用这一论点提供了直接的形态学依据.  相似文献   
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