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21.
Radiographic studies of three cases of hypoplasia of the humeral trochlea were done. Several other anomalies were also detected, including a hypoplastic capitellum in case 2, a hyperplastic radial head in cases 2 and 3, and bulging of the loose joint capsule in case 3. Operations in cases 1 and 3, disclosed that ganglions and fibrous septa compressed the ulnar nerve. The cause of ulnar nerve palsy in patients with hypoplasia of the humeral trochlea is thought to be associated with the high incidence of ganglions in hypoplastic elbow joints. The ganglion may play a role.  相似文献   
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Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors ( P <0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer.  相似文献   
24.
Primary extranodal malignant lymphoma frequently occurs in the gastrointestinal tract; however, it is rarely encountered in the rectum. We report herein the case of an 85-year-old man who underwent abdominoperineal resection for primary malignant lymphoma of the rectum, and 1 year later, developed hematemesis caused by gastric metastasis. To our knowledge this is the first case report of such distant metastasis developing from malignant lymphoma of the rectum.  相似文献   
25.
The activity of phrenic motor neurons is influenced by the cardiovascular control system of the supraspinal structures. In order to obtain the basic data for analyzing the anatomical relations between the cardiovascular and the pulmonary control system, supraspinal structures projecting to the phrenic motor nucleus of the cat spinal cord were studied using a horseradish peroxidase method. A double-barrel coaxial electrode was employed. To determine the site of the phrenic motor neurons, the inner barrel electrode, filled with 3 M NaCl solution, was used for recording the activity of these neurons. The outer barrel electrode, filled with a 20% HRP solution, was used for injecting HRP iontophoretically into the phrenic motor nucleus. Out of 13 experiments, 5 showed that the HRP-injection sites were centered in and almost confined to the phrenic motor nucleus. Some 1798 HRP-labeled cells were thus identified in the selected 5 experiments. They were distributed in the medulla oblongata (93.5%), pons (6.0%) and midbrain (0.5%). The majority were concentrated in the nucleus para-ambiguus (48.9%), nucleus tractus solitarii (21.5%) and in or around the nucleus retrofacialis (9.8%). A few labeled cells were scattered throughout the nucleus raphe (1.1%) and the parabrachial and Koelliker-Fuse nuclei (0.3%), suggesting that these nuclei may be, if any, only minor sources of input to the phrenic motor nucleus.  相似文献   
26.
To examine species differences in the distribution pattern of guanosine triphosphate (GTP)-binding protein (Go) within the vertebrate retina, paraffin-embedded retinae from a number of vertebrate species, including the goldfish, frog, turtle, chicken, monkey, and human, were immunohistochemically stained with affinity-purified antibody against the alpha-subunit of Go. Go-immunoreactive products were found to be located in the neuropil, but not in the cell bodies of neurons, in the retina of all these species. However, some species differences were observed. In the frog, monkey and human, the inner plexiform layer (IPL) was homogeneously stained with this antibody, but in the goldfish, turtle and chicken, the IPL was heterogeneously stained. In the frog, chicken, turtle and human, the outer plexiform layer (OPL) was densely stained with this antibody, but in the goldfish and monkey, the OPL was rather faintly immunoreactive to the antibody. In the goldfish, monkey and human, the outer nuclear layer (ONL) was not immunoreactive to the Go-antibody, whereas in the frog, turtle and chicken, the ONL was immunoreactive to it. The implications of these species differences in Go localization in the vertebrate retina are discussed.  相似文献   
27.
LD78 is a cDNA newly isolated from human stimulated tonsillar lymphocytes. The expression of LD78 is related to inflammatory responses and its structure has a homology with macrophage inflammatory protein 1-alpha, which is known to have an inhibitory effect on murine CFU-S. Using a colony assay technique, we examined the effects of LD78 on human hemopoietic progenitors. The addition of doses of 100 ng/ml or more of LD78 suppressed the colony formation of KMT-2, a factor-dependent myelomonocytic cell line established from cord blood cells; this suppressive activity was neutralized by the addition of antibody against LD78. The same doses of LD78 suppressed the formation of neutrophil, macrophage, and megakaryocytic colonies which were supported by human interleukin-3 and erythropoietin; however, LD78 did not affect colony formation by either non-phagocytic mononuclear cells or sorted CD34+ cells. The conditioned medium of KMT-2 cells or peripheral blood mononuclear cells cultured with LD78 suppressed colony formation by CD34+ cells. From these findings, it is suggested that LD78 affects phagocytic cells and induces factors that are inhibitory for hemopoiesis. We consider LD78 to be a new cytokine that plays an inhibitory role in hemopoiesis.  相似文献   
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29.
Male F344 rats were treated with lead nitrate and changes inthe expression and induction of P450IA subfamily enzymes anda placental form of glutathione-S-transferase (GST-P) in theliver were assessed by means of a bacterial mutation test, immunoblottingwith a monoclonal antibody reactive to P450IA1/IA2 and anti-GST-Psera and Northern blotting with P450IA2 cDNA as a probe. Treatmentof rats with lead nitrate (20, 50 or 100 µmol/kg bodywt) decreased P450IA2 mRNA and protein in the liver in the dose-dependentfashion and also decreased the microsomal activity for P450IA2-dependentmutagenization of aromatic amines. Pretreatment of rats withlead nitrate suppressed the inductions of both P450IA2 mRNAand protein by an inducer of P450IA subfamily enzymes in theliver. In addition, amount of the induced P450IA2 was decreasedalong with increase in that of the induced GST-P.  相似文献   
30.
To investigate how alveolar macrophages adapt themselves to oxidative pollutants in the long term, rats were exposed to a strong oxidant, ozone (O3), or a weak oxidant, nitrogen dioxide (NO2), for a maximum duration of 12 wk. After exposures, alveolar macrophages were collected by pulmonary lavage. Throughout 11 wk of exposure to 0.2 ppm O3, the specific activities of glucose-6-phosphate dehydrogenase (G6PDH) and glutathione peroxidase of the peroxidative metabolic pathway and pyruvate kinase and hexokinase of the glycolytic pathway were 40-70% elevated over the controls in alveolar macrophages. The population of alveolar macrophages was consistently 60% higher than the controls. The small-sized macrophages, immature macrophages, preferentially increased. To the contrary, the thymidine incorporation per cell was always 20-30% lower than in the controls, although the total incorporation remained unchanged. No infiltration of polymorphonuclear leukocytes occurred. By 12 wk of exposures to 1.2 and 4.0 ppm NO2, the population of alveolar macrophages increased 30% over the control. Among the enzymes examined, however, only the G6PDH activity increased 10% for 4.0 ppm NO2. No increase in the enzyme activities occurred for 1.2 ppm NO2. Based on these results, alveolar macrophages adapt themselves to the long-term exposure of O3 or NO2 by recruiting immature macrophages through an apparent influx of monocytes. During the exposure to O3, the peroxidative metabolic and glycolytic pathways are enhanced persistently in alveolar macrophages, whereas both pathways were not enhanced by the exposures to NO2.  相似文献   
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