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51.
52.
Theiler's murine encephalomyelitis virus (TMEV) is divided into two subgroups on the basis of their different biological activities. GDVII subgroup strains produce fatal poliomyelitis in mice without virus persistence or demyelination. In contrast, TO subgroup strains induce demyelinating disease with virus persistence in the spinal cords of weanling mice. Two proteins, whose open reading frames are located in the N-terminus of the polyprotein, recently have been reported to be important for TMEV biological activities. One is leader (L) protein and is processed from the most N-terminus of the polyprotein; its function is still unknown. Although the homology of capsid proteins between DA (a representative strain of TO subgroup) and GDVII strains is over 94% at the amino acid level, that of L shows only 85%. Therefore, L is thought to be a key protein for the subgroup-specific biological activities of TMEV. Various studies have demonstrated that L plays important roles in the escape of virus from host immune defenses in the early stage of infection. The second protein is a 17–18 kDa protein, L*, which is synthesized out-of-frame with the polyprotein. Only TO subgroup strains produce L* since GDVII subgroup strains have an ACG rather than AUG at the initiation site and therefore do not synthesize L*. 'Loss and gain of function' experiments demonstrate that L* is essential for virus growth in macrophages, a target cell for TMEV persistence. L* also has been demonstrated to be necessary for TMEV persistence and demyelination. Further analysis of L and L* will help elucidate the pathomechanism(s) of TMEV-induced demyelinating disease.  相似文献   
53.
2-O-methylisohemigossylic acid lactone, a sesquiterpene, was purified from roots of mokumen (Gossampinus malabarica) and identified by Mass, and (1)H- and (13)-NMR. This sesquiterpene displayed strong growth inhibitory effect against human promyelotic leukemia HL-60 cells. Apoptotic morphological change of the nucleus, including chromatin condensation was induced in the HL-60 cells treated with the sesquiterpene. The fragmentation of DNA by the sesquiterpene to oligonucleosomal-sized fragments, a characteristic of apoptosis, was observed to be dose- and time-dependent in the HL-60 cells. Inhibitors of caspases suppressed the DNA fragmentation induced by the sesquiterpene. These findings suggest that growth inhibition by the sesquiterpene of HL-60 cells results from the induction of apoptosis by the sesqui-terpene, and that caspase cascade is involved in the induction of apoptosis by the compound in the HL-60 cells.  相似文献   
54.
Clinical application to ascertain the effects of aspoxicillin (ASPC), a new semisynthetic penicillin antibiotic, upon several infectious diseases of children was performed in 7 cases with pneumonia, 5 cases with acute bronchitis, each case with tonsillitis, enterocolitis, urinary tract infection and suspected sepsis. ASPC was injected by drip infusion and the dosage was 63-117 mg/kg/day in 3 and 4 times a day. Clinical efficacy obtained as "excellent" was in 7 cases, "good" in 8 cases "poor" in 1 case, and efficacy rate was 93.8%. From the bacteriological point of view, eliminated in each of H. influenzae, H. parainfluenzae, group A beta-Streptococcus and unchanged in a case of E. coli. There were transient thrombocytopenia in 2 cases and eosinophilia in 3 cases.  相似文献   
55.
Ceftizoxime suppositories (CZX-S), containing 250 mg or 125 mg of CZX, were given to 6 children, 4 with acute bronchopneumonia and 2 with acute pharyngobronchitis, who were not suited to treatment with injectable or oral form of the drug. The clinical response was "good" in all the children and the causative organisms were eradicated in 2 children (H. influenzae or S. aureus). Adverse reactions consisted of 1 case each of diarrhea and transiently increased GPT. In conclusion, CZX-S proved to be highly effective in the treatment of bacterial infections in children.  相似文献   
56.
In a comparative study of MR images of 289 neurosurgical patients, loss of the signal intensity (signal void phenomenon) of CSF in the aqueduct was observed in 77 patients. This signal void phenomenon was seen most frequently in infants with chronic subdural hematoma (12 of 18) and patients of all age groups suffering from communicating hydrocephalus (10 of 14). It is known that CSF in the cranial cavity flows toward the spinal CSF space in to and fro manner responding to brain parenchyma pulsations. The velocity of this flow is to be faster in the narrower parts through the ventricular systems such as the aqueduct, Monro's foramen and the 4th ventricles. We think that in T2 weighted images signal void phenomenon reflects "high velocity signal loss" due to CSF flow. When the subarachnoid adhesions secondary to subarachnoid hemorrhage stagnate CSF flow in the subarachnoid space, the intraventricular CSF flow forms the main buffer for changes of the brain volume. This causes an increase in the amplitude of the pulsatile flow in the ventricular systems. Therefore the signal void phenomenon in the aqueductal CSF becomes more pronounced. It may be possible to differentiate normal circulation of CSF from abnormal with the bigger amplitude of CSF pulsatile flow, to understand the mechanisms of the normal pressure hydrocephalus or to diagnose a shunt malfunction. Therefore more insight in the CSF flow as imaged by MRI is needed, quantification of CSF flow will be the subjects of our further research.  相似文献   
57.
ObjectivesTo investigate the association between Ki67 index and programmed death-ligand 1 (PD-L1) expression in muscle-invasive bladder cancer (MIBC) patients after RC.Materials and MethodsWe retrospectively evaluated 262 MIBC patients treated with RC between April 2004 and April 2020. The impact of Ki67 index and PD-L1 expression on prognosis was evaluated by univariate Cox regression analysis. In addition, a pathomolecular risk score, including Ki67 and PD-L1, was developed to predict prognosis and pathological factors. We also evaluated the link between the Ki67 index and PD-L1 under the IL-6 stimulation in the bladder cancer cell lines of T24 and 5637 cells.ResultsThe median age and follow-up period was 69 years and 52 months, respectively. Ki67 index and PD-L1 expression were significantly associated with tumor recurrence. Univariate Cox regression analysis showed that pT3–4, mixed histology, lymphovascular invasion positive (LVI+), pN+, Ki67-high (>17%), and PD-L1+ were significantly associated with recurrence-free survival (RFS). The pathomolecular risk score was developed using resection margin+ (1 point), mixed histology (1 point), LVI+ (1 point), pN+ (1 point), and Ki67-high (1 point). RFS and overall survival were significantly shorter in patients with higher pathomolecular risk scores (>1) than in those with lower risk scores (≤1). Cell proliferation was significantly increased in the T24 and 5637 cells under the IL-6 stimulation, while PD-L1 expression was not.ConclusionsA significant effect of Ki67-high and PD-L1 expression on poor prognosis was observed in patients with MIBC. Further studies are necessary to elucidate the precise mechanisms of cell proliferation and PD-L1 expression in patients with MIBC.  相似文献   
58.
Radiation tolerance of the partially irradiated liver was studied in eight patients with primary hepatoma treated by a multimodal approach. Seven patients were treated by transarterial embolization therapy (TAE) with Lipiodol-MMC, and two patients were treated by operation, combined with radiotherapy. Six patients had liver cirrhosis and the other one had renal dysfunction. Respiration-gated irradiation was employed to reduce a treatment volume for seven patients. Radiation portals were carefully tailored using the embolized Lipiodol or a metal clip inserted into the tumor as references. Two or three portals were used for each patient. The treatment volume ranged from 64 to 1400 cm3. The target dose ranged from 50.4 Gy to 81.0 Gy, from 73.5 to 108.6 in TDF. Liver function tests (GOT, GPT, LDH, ALP, ChE and total Bilirubin) were examined for 30 weeks after initiation of irradiation. Three patients showed abnormal value in more than 5 tests. Of these three patients, the hepatic hilum was included in the treatment volume in two, and the tumor progressed during the observation period in two. Leukopenia and thrombopenia were observed, but these values were not below 2000 and 40000/mm3, respectively, although the thrombocyte count before irradiation was below 100000/mm3 in 7 patients. AFP titers decreased after the treatment in six out of seven patients with abnormally elevated pretreatment titer. The survival period after staring irradiation was 6.5 to 25 months. "The volume dose" did not correlate well with the degree of the liver function aggravation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
59.
The influences of intra-aortic balloon pumping (IABP) on arterial flow of the superior mesenteric artery were assessed by Doppler echocardiography. The subjects were 13 patients postoperatively, requiring IABP support to control low cardiac output state, in which distal aspects of balloons were distal to the superior mesenteric artery. Superior mesenteric flow velocity integral in systole (IntS) and that in diastole (IntD) were measured from superior mesenteric flow pattern, and the sum of IntS and IntD (IntS + IntD) was calculated ON and OFF balloon pumping (IABP ON-OFF test). The same parameters were obtained with balloon inflating on every other beat (IABP 1:2 test); the cardic cycle with balloon assist was defined as "1:2 ON", and that without balloon assist was defined as "1:2 OFF". 1) IABP ON-OFF test. IABP increased IntS from 7.07 +/- 2.56 cm to 9.20 +/- 3.19 cm (p less than 0.05), IntD from 3.00 +/- 1.18 cm to 3.62 +/- 1.40 cm (p less than 0.05), and IntS + IntD from 10.07 +/- 3.48 cm to 12.82 +/- 4.04 cm. Cardiac output increased from 3.89 +/- 1.34 l/min to 4.24 +/- 1.64 l/min with IABP support. The increments in IntS, IntD and IntS + IntD with IABP are attributed, to a large extent, to an increase in cardiac output. 2) IABP 1:2 test. Without balloon inflation, IntS increased (1:2 ON; 7.16 +/- 2.91 cm, 1:2 OFF; 8.41 +/- 3.30 cm, p less than 0.05), and IntD decreased (1:2 ON; 3.51 +/- 1.60 cm, 1:2 OFF; 2.33 +/- 1.25 cm, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
60.
A 52-year-old Japanese woman developed dermatomyositis. She had undergone a standard radical mastectomy for left breast cancer 21 years earlier. Though no physical sign of recurrent breast cancer appeared clinically, levels of tumor markers were abnormally elevated. Therefore, tamoxifen and CAF therapy were given. Further, the clinical course of dermatomyositis almost paralleled the level of serum tumor markers and the clinical course of her recurrent breast cancer. These markers were useful for detecting the recurrence, following the metastatic disease, and monitoring her response to therapy.  相似文献   
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