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61.
SUMMARY: Surgical outcomes for tethered spinal cord syndrome (TCS) associated with low-lying conus medullaris were evaluated. We investigated the long-term results of untethering the spinal cord and dural plasty in surgical patients with a wide age range. Improvement of bladder dysfunction and suppression of leg deformity progression were noted in two pediatric patients. However, severe urinary dysfunction generally remained postoperatively. Adult patients commonly showed low back or leg pain as clinical manifestations. In seven adult patients, urinary dysfunction also improved. Neurologic findings and urinary deficits showed a favorable improvement mostly in adult TCS in comparison with natal or juvenile onset of TCS. A short duration from onset to surgery and cranial movement of the conus medullaris as assessed by postoperative magnetic resonance imaging were factors indicating a favorable prognosis.  相似文献   
62.
This experiment was designed to test the hypothesis that endogenous corticotropin-releasing factor (CRF) contributes to the neurodegenerative process following an ischemic insult. To test this hypothesis, the effects of chronic intracerebroventricular administration of CRF or astressin, a CRF-receptor antagonist, on the decrease in the Schaffer collateral-CA1 field potential induced by hypoxia/hypoglycemia (ischemia), were tested in rat hippocampal slices. The chronic treatment with CRF had a significant exacerbating effect on the 10-min ischemia, a condition that did not affect the evoked synaptic response in the hippocampal CA1 area, as compared to vehicle-treated rats. On the other hand, astressin had a significant ameliorative effect on the 15-min ischemia-induced reduction of the evoked synaptic response in the hippocampal CA1 area. These findings suggest that CRF accelerates hippocampal ischemic vulnerability induced by hypoxia and hypoglycemia.  相似文献   
63.
To clarify the mechanisms underlying the antihypertensive effect of Luobuma (Apocynum venetum L. (Apocynaceae)) leaf extract (LLE), we investigated the vasodilator effect of LLE in the rat mesenteric vascular bed, which plays an important role in changes in peripheral resistance and thus the regulation of blood pressure. In the perfused mesenteric vascular bed with active tone and intact endothelium, perfusion of LLE (0.1 ng to 100 mg/ml for 15 min) caused dose-dependent vasodilation, which was abolished by chemical removal of the endothelial layer with perfusion of sodium deoxycholate, but not by N(G)-nitro-L-arginine-methyl ester (L-NAME), a competitive inhibitor of nitric oxide (NO), which instead increased the effect. The LLE-induced vasodilation was partially inhibited by high K(+)-containing Krebs solution and tetraethylammonium (a K(+) channel blocker) and completely by the combination of L-NAME and high K(+)-Krebs solution. However, atropine (a muscarinic acetylcholine receptor antagonist) did not affect the vasodilation. These results suggest that the vasodilation induced by LLE is endothelium-dependent and mediated by endothelium-derived hyperpolarizing factor, which involves the activation of K(+)-channels. The higher concentrations of LLE may enhance NO production/release to cause vasodilation.  相似文献   
64.
Use of dialysate as supplement fluid in hemodiafiltration requires controlling contamination by endotoxin of the dialysate. We thus aimed at developing an endotoxin monitoring system with complete exclusion of endotoxin contamination for simple, easy, and accurate measurement of endotoxin concentration in dialysate. In the present study, we used a 6 valve injector along with a high performance liquid chromatogram system. This new system showed a sensitivity of approximately 1 endotoxin units (EU)/L in the range of 0 to 30 EU/L endotoxin in dialysate and no trace of endotoxin contamination. In conclusion, the new endotoxin monitoring system showed high sensitivity and reproducibility, with easy operation.  相似文献   
65.
BACKGROUND: Anomalous union of the pancreatic and biliary ducts (AUPBD) is characterized by the intersection of these ducts proximal to the sphincter of Oddi. Thus, the relative anatomic relationship between the pancreaticobiliary ductal union and the narrow distal segment of the bile duct, which represents the functional sphincter, on cholangiopancreatograms determines whether the ductal union is normal or anomalous. This study examined whether the length of the common channel or that of the narrow distal segment is more closely associated with AUPBD and defined radiographic criteria for AUPBD. METHODS: The length of the common channel and of the narrow distal segment were measured directly on cholangiopancreatograms from 350 patients. RESULTS: AUPBD was found in 36 patients (10%). The common channel was significantly longer in patients with AUPBD (p < 0.001), whereas the length of the narrow distal segment was comparable between patients with and without AUPBD (p = 0.38). There was considerable overlap in the range of the length of the common channel between patients with and without AUPBD. CONCLUSIONS: The length of the common channel is closely associated with the presence of AUPBD. However, a diagnosis of AUPBD based on the length of the common channel is not reliable. The diagnosis of AUPBD continues to rely on the radiographic criterion of a pancreaticobiliary ductal union located proximal to the narrow distal segment, which represents the sphincter of Oddi.  相似文献   
66.
67.
Innervation of calf muscles in relation to calf reduction   总被引:7,自引:0,他引:7  
Plump and muscular calves, a so-called radish-like leg, embarrass young women and cause a feeling of inferiority in Korea. Damage to motor nerves innervating a muscle makes the muscle paralyzed and dystrophic, with loss of muscle volume. The authors studied the morphometry of the motor branches of the tibial nerve innervating the gastrocnemius and soleus muscle and sensory medial sural cutaneous nerve in popliteal fossa. Dissection and exploration of the tibial nerve were performed in the popliteal fossae of 70 legs (of 18 males and 17 females) of embalmed Korean cadavers. The main branch of the tibial nerve innervating medial and lateral gastrocnemius muscle originated 3 cm above and below the popliteal crease. The medial gastrocnemius muscle had an additional nerve (49%). The medial sural cutaneous nerve came off the nerve into the medial gastrocnemius muscle (30%) and diverged 5.5 mm from the tibial nerve. The nerve into the soleus muscle originated from the nerve innervating the lateral gastrocnemius muscle (30%) and was 12.3 mm away from it. Surgeons should keep in mind that the medial sural cutaneous nerve originates from the nerve to medial gastrocnemius in 30% and the nerve to soleus muscle originates from the nerve to lateral gastrocnemius in 30%.  相似文献   
68.
Since virus-specific cytotoxic T lymphocytes (CTLs) play a critical role in preventing the spread of hepatitis C virus (HCV), an effective HCV vaccine should be capable of eliciting HCV-specific CTLs. In the present study, we assessed the capability of a novel recombinant vaccine using an attenuated tuberculosis bacillus, Calmette-Guerin bacillus (BCG), as a vaccine vehicle to elicit HCV-specific CTLs. BCG was engineered to express the CTL epitope of HCV-non-structure protein 5a (NS5a) as a chimeric protein with alpha antigen of mycobacteria. Immunization with this recombinant BCG elicited major histocompatibility complex class I-restricted CD8(+) HCV-NS5a-specific CTLs in mice. Immunized mice showed a substantial reduction in the vaccinia virus titer compared with control mice when the immunized mice were challenged with a recombinant vaccinia virus expressing HCV-NS5a genes. These findings provide evidences for the possibility of BCG as a vaccine vector and its continued exploration as a vehicle for eliciting HCV-specific immunity.  相似文献   
69.
We measured and compared the levels of plasma monocyte-derived microparticles (MDMP) and platelet activation markers [plasma platelet-derived microparticles (PDMP), CD62P binding to platelets; plt-CD62P, CD63 binding to platelets; plt-CD63], to develop a better understanding of their potential contribution to vascular complications of lung cancer. The concentrations of MDMP and PDMP in lung cancer patients were significantly higher (P < 0.01) than those in normal subjects. Levels of plt-CD62P and plt-CD63 were significantly higher (P < 0.001 for each) in lung cancer patients than in controls. Levels of sE-selectin were also higher in lung cancer patients than in control subjects. MDMP correlated positively with plt-CD62P, plt-CD63, and PDMP with its relation to PDMP being particularly significant. The number of MDMPs and PDMPs are patients who are non-small cell lung cancer were significantly higher than that in small cell lung cancer patients. In addition, levels of sE-selectin were higher in non-small cell lung cancer than in small cell lung cancer patients. These findings suggest that elevated MDMPs may be a sign of vascular complication in lung cancer patients, particularly those who suffer from non-small cell lung cancer.  相似文献   
70.
The efficacy and safety of the oral fluoropyrimidine TS-1, which contains a dihydropyrimidine dehydrogenase (DPD) inhibitor, were examined in fifty-five patients with gastric cancer. The patients were divided into 28 with measurable cancer lesions (TUM group) and 27 without them (ADJ group). The total number of courses was 164 (mean: 5.9 courses) in the TUM group and 146 (mean; 5.4 courses) in the ADJ group. The response rate in the TUM group, excluding three patients who could not be evaluated because of incomplete administration, was 40% (CR: 4, PR: 6, NC: 6, PD: 9). Among responders, the mean number of courses to response was 2.2 and the median survival time (MST) was 21.7 months. In terms of safety, adverse reactions appeared in forty-five patients (82%) and the incidence was higher in the ADJ group. Major toxicities were leukopenia (38%), anorexia (27%), increased total bilirubin concentration (25%) and diarrhea (24%). Adverse reaction of grade 3 was found in only three patients (5.5%) and there were no drug-related deaths. In conclusion, TS-1 is safe and effective if attention is given to biweekly examinations for the development of adverse reactions.  相似文献   
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