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91.
Distribution and morphology of the cells of origin of the descending spinal pathways and their axonal courses were studied in the himé salmon, using retrograde labelling with cobaltic lysine and horseradish peroxidase (HRP). Following application of the tracers to the cut end of the spinal cord or injection of the tracers at the 10th to 15th spinal segment, neurons mainly labelled via the axons of passage were distributed in the mesencephalon and the rhombencephalon. Mesencephalic cell groups consisted of the nucleus pretectalis, the nucleus fasciculi longitudinalis medialis, and the nucleus ruber. The former two cell groups sent their axons to the fasciculus longitudinalis medialis. The axons of the nucleus ruber formed a separate loose bundle, the "tractus rubrospinalis." The rhombencephalic cell groups consisted of the rhombencephalic reticular formation, the Mauthner cells (one cell for each side), and the octavolateral area. The rhombencephalic reticular formation could be further subdivided into the nucleus reticularis superior, nucleus reticularis medius, and nucleus reticularis inferior. The axons of these cell groups joined the fasciculus longitudinalis medialis and the "tractus bulbospinalis." The Mauthner cell had two main gigantic dendrites, and its giant axons formed a conspicuous fiber of Mauthner throughout the rhombencephalon down to the spinal cord. The octavolateral area could be subdivided into the nucleus vestibularis magnocellularis, nucleus tangentialis, nucleus vestibularis descendens and nucleus intermedius. The axons of the nucleus vestibularis magnocellularis and nucleus intermedius entered the fasciculus longitudinalis medialis and/or the tractus bulbospinalis. Those of the nucleus vestibularis descendens and nucleus tangentialis formed the "tractus vestibulospinalis". The descending spinal pathways of the himé salmon were compared with those of other fishes and other vertebrates. The significance of these descending spinal pathways in the control of locomotion and sexual behavior is also discussed.  相似文献   
92.
To investigate the relationship between the site of ruptured cerebral aneurysm and rCBF, 92 measurements of rCBF were conducted in 57 patients with ruptured cerebral aneurysm. Excluded from this study were patients with multiple aneurysms, intracerebral hematoma, and/or hydrocephalus. Twenty-four patients had the anterior communicating aneurysm (A-com), 20 patients had the internal carotid aneurysm (ICA), and 13 patients had the middle cerebral aneurysm (MCA). All patients underwent unilateral fronto-temporal craniotomy for clipping of the aneurysm and their rCBF measurements, using the xenon-133 inhalation method, were performed in the first three weeks after surgery. In each rCBF measurement, the hemispheric mean value of initial slope index (meanISI) was calculated in both cerebral hemispheres, that is, in the cerebral hemispheres ipsilateral and contralateral to craniotomy. The authors defined the "symmetry index of the meanISI (%): symmetry index" as the ratio of the meanISI in the cerebral hemisphere ipsilateral to craniotomy compared to the meanISI in the cerebral hemisphere contralateral to craniotomy. There was no significant relationship between the site of aneurysm and the meanISI in both hemispheres, and this result suggests that the site of aneurysm makes no difference in the incidence of vasospasm. In the postoperative first week, the "symmetry index" was 91.2 +/- 7.4% in MCA, 95.3 +/- 4.1% in ICA, and 97.9 +/- 8.2% in A-com; that is, MCA had significant asymmetry of meanCBF compared with A-com (p less than 0.05). In the second and third postoperative weeks, there was no significant relationship between the site of aneurysm and the asymmetry of meanCBF.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
93.
The role of each enkephalin-hydrolyzing peptidase in the inhibitory potency of exogenously added enkephalins in the myenteric plexus-longitudinal muscle preparation of guinea-pig ileum was studied by using the relatively specific inhibitor of each enzyme. Results showed that three distinct enzymes, bestatin-sensitive aminopeptidase(s), angiotensin converting enzyme, and thiorphan-sensitive "enkephalinase", played a critical role in the inactivation of enkephalins. Additionally, these enzymes are likely to be located close to opioid receptors, since they produce a significant concentration difference of enkephalin between the surrounding organ bath and the vicinity of opioid receptors. In contrast to these three enzymes, both L-tyrosyl-L-tyrosine-sensitive dipeptidyl aminopeptidase and D-phenylalanine-sensitive carboxypeptidase are indicated not to be involved significantly in the degradation of exogenously added enkephalins in the guinea-pig ileum.  相似文献   
94.
The natural killer (NK) activity of peripheral blood mononuclear cells and serum immunosuppressive acidic protein (IAP) levels were examined in patients with esophageal or gastric cancer, before and after surgery. Patients with stage IV esophageal or stage IV gastric cancer had significantly lower NK activity (39.5±14.8% and 37±11.6%, respectively), and also higher serum IAP levels (778±264 g/mL and 633±156 g/mL, respectively), than the corresponding control values (50±5.6% and 375±26 g/mL, respectively). Patients with esophageal or gastric cancer who underwent curative resection had high NK activity (54.8±11.6% and 54.8±8.0%, respectively), and low IAP levels (471±116 g/mL and 490±42 g/mL, respectively), compared with those who underwent non-curative resection. Patients who underwent non-curative resection had lower NK activity and higher serum IAP levels than those who underwent curative resection, even 1 month after surgery. Mononuclear cells in the regional lymph nodes and tumor specimens showed significantly lower NK activity than those in the peripheral blood and spleen. Thus, NK activity and the IAP level reflected the immunocompetence, clinical course, and surgical curability of those patients. NK cells appeared not to have any significant antitumor activity in the regional lymph nodes or in the tumor itself, although they were still active in the peripheral blood.  相似文献   
95.
Purpose. To clarify the mechanism of the renal clearance of recombinant human interleukin-11 (rhIL-11), we investigated the renal disposition characteristics of rhIL-11 in the perfused rat kidney. Methods. The disposition characteristics of 111In-labeled rhIL-11 were analyzed using a single-pass indicator dilution technique and statistical moment analysis in the perfused rat kidney under filtering and nonfiltering conditions. Results. Steady-state distribution volume (V d ) calculated from the venous outflow patterns of rhIL-11 at the doses of 0.3 to 10 g/kidney was between 0.35 and 0.40 ml/g kidney. However, V d at the highest dose decreased to a value almost identical to that of bovine serum albumin, suggesting that there is a reversible and saturable interaction between the capillary wall and rhIL-11 molecule. In filtering kidney, a remarkable accumulation of rhIL-11 was observed while its urinary excretion was highly restricted at all doses. In nonfiltering kidney, rhIL-11 showed a decreased but still significant renal uptake. Taken together, the marked renal uptake of rhIL-11 may be explained by both efficient tubular reabsorption and significant uptake from the capillary side. These processes were not saturable within the tested dose range. These characteristics of rhIL-11 are likely based on non-specific electrostatic interaction with the tissues due to its cationic charge in the cytokine. Conclusions. The renal disposition processes of rhIL-11 were clarified at organ level in a quantitative manner. These findings agree well with previous observations in an in vivo disposition study in mice.  相似文献   
96.
Interleukin-6 (IL-6) levels have been shown to correlate well with the magnitude of surgical stress. Serum IL-6 and plasma granulocytic elastase levels, 24 h after surgery, were determined in 12 patients who underwent open major surgery [MS group; esophageal carcinoma (n=5), gastric carcinoma (n=3), colorectal carcinoma (n=4) 5 patients who had open cholecystectomy [OC group] and 17 patients who had laparoscopic cholecystectomy [LC group]. IL-6 levels correlated significantly with the duration of surgery (r=0.685,P < 0.01) and with intraoperative blood loss (r=0.583,P < 0.02). However, there was no significant correlation between granulocytic elastase and the duration of surgery or blood loss. Plasma IL-6 levels in the LC group (21±3 pg/ml) were significantly lower than those in the OC group (47±5 pg/ml) and the MS group (186±36pg/ml) (P<0.05;P<0.01). However, there was no significant difference in granulocytic elastase levels between the LC group (318±8g/l), the OC group (360±130 gmg/ml), and the MS group (701±344 g/l). Increased IL-6 levels correlated well with increased duration of surgery. The lower IL-6 levels following laparoscopic cholecystectomy may therefore be indicative of lower surgical stress associated with laparoscopic cholecystectomy.  相似文献   
97.
The procedure of aspiration biopsy cytology by fine needle aspiration (ABC) is as option in establishing definitive diagnoses for breast cancers. In this series, a needle size of 21G was considered most suitable for ABC as well as flow cytometric DNA analysis. Histograms from fresh samples aspirated by fine needle clearly delineated a sharp peak in G&sup0;G(1) phases and also a better CV was obtained than with paraffin-embedded preparations. In addition, fresh samples gave more reliable DI and suggested the value of measuring nuclear DNA contents. It is believed that the prognoses of breast cancers are closely associated with DNA ploidy patterns. In this sense, flow cytometric DNA analysis of fresh samples of ABC is regarded as important in clinical use.  相似文献   
98.
Mechanical stimulation of one mammary tumor cell in culture induced an increase in its intracellular calcium concentration which spread to surrounding cells. The increase in calcium can also be induced by addition of a solution in which cultured mammary tumor cells were stimulated by repeated pipetting (solution after pipetting cells, SAPC). The activity of the SAPC was completely abolished by treatment with snake venom phosphodiesterase or pyrophosphatase. Uridine triphosphate (UTP), uridine diphosphate (UDP) and ATP (1 M each) were detected in the SAPC, whereas 5-UMP and 5-AMP were produced by phosphodiesterase digestion. A mixture of UTP, UDP and ATP (1 M each) elicited a calcium response which was comparable to that induced by SAPC, while UTP, UDP or ATP alone at 1 M elicited a small increase in calcium concentration in mammary tumor cells. Suramin, a competitive antagonist of P2 purinoceptors, diminished the spreading of the calcium wave induced by mechanical stimulation. It also blocked the responses to SAPC, UTP, UDP and ATP. These findings suggest that the mechanical stimulation results in the release of UTP, UDP and ATP into the extracellular space which mediates induction of the spreading calcium response via P2U-type purinoceptors.  相似文献   
99.
Splenic inflammatory pseudotumor is extremely rare and may mimic splenic neoplasms, such as lymphomas or hamartomas, clinically and radiologically. A case of a surgically proved splenic inflammatory pseudotumor is presented in which Tc-99m colloid SPECT and Ga-67 scintigraphy characterized the changes in the spleen, but the findings of ultrasound and unenhanced CT and MRI were nonspecific. This report indicates the utility of radionuclide imaging for diagnosing splenic inflammatory pseudotumor.  相似文献   
100.
In this paper we present a new technique for thymic cystectomy by video-assisted thoracic surgery. The thoracoscope was inserted using a Vein Harvest (Ethicon Endo-Surgery Co, Ltd, Cincinnati, OH) through a 5-cm subxyphoid incision. A Harmonic Scalpel (Ethicon Endo-Surgery) and Cherry Dissector (Ethicon Endo-Surgery) were used for dissection. The thymic cyst was successfully removed through the incision without thoracotomy. The advantage of this technique is that it is less invasive than video-assisted thoracic surgery through the thorax, removing the need for a thoracotomy.  相似文献   
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