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91.
Infant cranial sonography   总被引:1,自引:0,他引:1  
Sonography is well recognized as an excellent method of imaging the infant brain. A detailed discussion of the sonography of the preterm patient forms the first portion of this article. The numerous other clinical situations in which sonography can be used either alone or in conjunction with CT follow.  相似文献   
92.
The differentiation of intracerebral and intraspinal transplants of fetal (E14-E15) rat spinal cord was studied to determine the extent to which myelin-free zones in these embryonic grafts exhibit cytological features and immunocytochemical characteristics of the substantia gelatinosa (SG) of the normal spinal cord. Immunocytochemical staining with antiserum to myelin basic protein (MBP) revealed myelin-free areas of varying proportions within fetal spinal cord grafts. These regions were identified in both newborn and adult recipients regardless of whether donor tissue was grafted to heterotopic (intracerebral) or homotopic (intraspinal) sites. As in the SG of the intact spinal cord, the myelin-free regions consisted mainly of small (7-15 microns) diameter neurons. At the ultrastructural level, these cells were surrounded by a neuropil composed of numerous small caliber, unmyelinated axons and intermediate-sized dendrites. Synaptic terminals in these areas were primarily characterized by the presence of clear, round vesicles, although granular vesicles were occasionally found within these terminals. Immunocytochemical staining demonstrated met- and leu-enkephalin-, neurotensin-, substance P-, and somatostatin-like immunoreactive elements within these myelin-free areas. Thus, regions within embryonic spinal cord grafts undergo some topographical differentiation which parallels that of the normal superficial dorsal horn. The presence of SG-like regions illustrates the potential capacity of fetal spinal cord transplants for replacing some intraspinal neuronal populations at the site of a spinal cord injury in neonatal and adult animals. These graft regions may serve as a source of intersegmental projection neurons or establish an extensive intrinsic circuitry similar to that seen in the normal SG. In addition, the definition of these areas provides a useful model to study the innervation patterns of host axons that typically project to the substantia gelatinosa of the normal spinal cord.  相似文献   
93.
94.
Because the eye is involved in about 25% of patients with active sarcoid, the ophthalmologist is often the first physician to see these patients. Although clinical findings may suggest sarcoid, laboratory tests (e.g., x-ray, skin tests, blood chemistries, etc.) may be normal or inconclusive. Thus, it is important that the ophthalmologist be aware of the availability and limitations of the various biochemical, immunological, radiological, and histopathological tests that contribute to the early diagnosis of sarcoidosis. The authors review diagnostic procedures and present a flowchart detailing indications for each.  相似文献   
95.
The purpose of this study was to determine what happens to normal aqueous lysozyme levels during experimentally induced uveitis. Horse-serum-induced uveitis increased the average rabbit aqueous lysozyme value (0.9 mug per milliliter) to 13.8 mug per milliliter, but did not elevate the average serum lysozyme value (4.0 mug per milliliter). These findings suggest that ocular inflammation alone is not sufficient to elevate the serum lysozyme level.  相似文献   
96.
97.
The purpose of this study is to separate out the effects of number of siblings and birth order on children's use of physician services. Prior research has consistently revealed an inverse relationship between family size and physician visits, but the possible confounding influence of the child's ordinal position in the family has been ignored. Later born children may be taken to the doctor less often than first and other early borns because of their parents' increasing knowledgeability in regard to child care as well as their growing understanding of the uses and limitations of physician visits. On the assumption that part of the family size effect observed in prior research may have been due to the clustering of first and early borns in small families, an inverse relationship between birth order and physician utilization is hypothesized. Support for this hypothesis comes from an empirical study of 1,665 children from 587 families in which variation in family size is statistically controlled.  相似文献   
98.
本实验对8条犬进行小肠肌电测定,并在记录期间分别静注胆碱能神经阻断剂,阿托品和六甲季胺,以及5-羟色胺(5-HT)M受体阻断剂,灭吐灵,以观察其对红霉素所致肠道副作用的影响。结果发现阿托品和六甲季胺不仅能明显地抑制空腹时正常传播性肌电综合波(MMC)的发生和传播,降低红霉素促进小肠动力的作用,还能减轻红霉素所致饱腹动物的快波数增加,但对呕吐无明显影响。灭吐灵的实验结果显示红霉素的致吐作用是由5-HTM受体介导的,与其促进小肠动力的作用无明显因果关系。  相似文献   
99.
100.
C W Herman  A N Tessler 《Urology》1983,22(1):49-50
A case report of extragenital tumor of müllerian type arising from the posterior peritoneum and compressing the kidney is presented. The embryologic basis for this type of tumor arising in the peritoneum is discussed.  相似文献   
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