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61.
The synthesis and antitumor evaluation of 2, 5-disubstituted-indazolo[4,3-gh]isoquinolin-6(2H)-ones (9-aza-APs) are described. The key intermediates in the synthesis are benz[g]isoquinoline-5,10-diones which are substituted at positions 6 and 9 with groups of different nucleofugacity for SNAr displacements. The initial displacement of fluoride by a substituted hydrazine leads to the pyrazole analogues. Substitution of the remaining leaving group by an amine or BOC-protected amines leads to the 9-aza-APs 12. These analogues were converted into their maleate or hydrochloride salts 13. In two cases, namely, 13x and 13z, sidearm buildup was also employed in the synthetic pathway. In vitro evaluation of 9-aza-APs against the human colon tumor cell line LoVo uncovered for most of the compounds a cytotoxic potency lower than that of DuP-941 or mitoxantrone and comparable to that of doxorubicin. Only analogues 13c, 13n, and 13ff were as cytotoxic as DuP-941. Interestingly, while DuP-941 was highly cross-resistant in the LoVo cell line resistant to doxorubicin (LoVo/Dx), the 9-aza-APs carrying a distal lipophilic tertiary amine moiety in both chains were capable of overcoming the MDR resistance induced in this cell line. The 9-aza-APs show outstanding in vivo antitumor activity against both systemic P388 murine leukemia and MX-1 human mammary carcinoma transplanted in nude mice. At their optimal dosages, congeners 13a-c, 13f, 13n, 13q, 13x, and 13dd were highly effective against P388 leukemia with T/C% of 200-381, while the T/C% value of DuP-941 was 147. In the MX-1 tumor model, 24 compounds elicited percentages of tumor weight inhibitions (TWI) ranging from 50% to 99%. Congeners 13d, 13k, 13l, 13x, 13z, and 13ee emerged as the most effective ones, with TWI% 96, simliar to that of DuP-941 (TWI% = 95). On the basis of their efficacy profile in additional experimental tumors and lack of cardiotoxicity in preclinical models, two congeners have surfaced as potential clinical candidates.  相似文献   
62.
The authors describe a case of metastatic endocarditis associated with a gastric carcinoma. The diagnosis was made early and the treatment by surgery and chemotherapy allowed a survival of 18 months, which is unusually long. The differential diagnosis is discussed and includes nonbacterial thrombotic endocarditis, infectious endocarditis and primary tumors of the heart.  相似文献   
63.
OBJECTIVES: To determine whether oxytocin exists in the cerebrospinal fluid (CSF) of dogs and whether the amount of oxytocin in the CSF of dogs with neck or back pain caused by spinal cord compression is significantly different than that in the CSF of clinically normal dogs. STUDY DESIGN: Prospective controlled study. ANIMAL POPULATION: A total of 15 purpose-bred beagles and 17 client-owned dogs. METHODS: CSF was collected by needle puncture of the cerebellar medullary cistern after induction of general anesthesia. Oxytocin levels within the samples were determined through radioimmunoassay. RESULTS: Dogs with spinal cord compression had significantly more oxytocin in their CSF than the clinically normal dogs (13.76 +/- 2.0 pg/mL and 3.61 +/- 0.63 pg/mL, respectively; P < .0001). Dogs with chronic signs (>7 days) had significantly more oxytocin in their CSF than dogs with acute signs (<7 days) (21.60 +/- 0.86 pg/mL and 6.80 +/- 0.81 pg/mL, respectively; P < .0001). Both acutely and chronically affected dogs had significantly more oxytocin in their CSF than the controls (P < .005 and P < .0001 respectively). CONCLUSIONS: Dogs with neck and back pain caused by spinal cord compression have significantly more oxytocin in their CSF than clinically normal dogs. Dogs with chronic clinical signs have significantly more oxytocin in their CSF than dogs with acute clinical signs. CLINICAL RELEVANCE: In humans, intrathecal injection of oxytocin is effective in treating low back pain for up to 5 hours. Intrathecal oxytocin may be a logical choice for perioperative analgesia in dogs undergoing myelography because the intrathecal space is accessed for injection of contrast agent.  相似文献   
64.
For six weeks, recipient (Lewis RT11) and donor rats (LBNF11/n) were fed three diets that varied only in their lipid content. Diet A (MO) contained 19.5% menhaden oil and 0.5% safflower oil and was rich in omega 3 PUFA; diet B (SO) was 20% safflower oil rich in omega 6 PUFA; and diet C (BT) was 20% beef tallow rich in omega 9 monounsaturated fatty acids and saturated fat. In the first set of graft survival studies a group fed laboratory chow was included (CHOW). Heterotopic cardiac transplantation from donor to recipient animals was performed after the six-week feeding period. The effect of these diets on cardiac allograft survival, mixed lymphocyte response, and blood flow in the rejecting grafts was investigated. The median graft survival in days was significantly prolonged in the rats maintained on either MO (12 days) or SO (14.5 days) compared with the BT (8 days)-or lab chow (7.5 days)-fed animals (P < 0.05). Cyclosporine (CsA) administered at subtherapeutic levels further increased the differences between the PUFA-fed animals and the BT-fed group. The myocardial blood flow of the rejecting allografts was measured using an 85Sr-labeled microsphere technique on the fifth posttransplant day. Flow was greatest in the MO-fed group, and both MO and SO groups had significantly higher myocardial blood flow than BT-fed rats (P < 0.05) or those bearing isografts. The allogenic mixed lymphocyte responses of peripheral blood mononuclear cells (PBMC) and splenic lymphocytes were suppressed in MO- and SO-fed groups compared with BT-fed animals. The immunosuppressive effect of dietary PUFA warrants further investigation, and their use as a possible adjunctive treatment in organ transplantation should be considered.  相似文献   
65.
Central nervous system (CNS) disease is a major feature of simian immunodeficiency virus (SIV) infection of macaques. To define the spectrum of CNS lesions in SIV-infected macaques and the potential associations with viral strain and disease course, we performed a retrospective analysis of necropsies on 124 macaques with SIV-induced AIDS. Histologic evidence of CNS disease was observed in 71 (57.3%) of the 124 animals. SIV encephalitis was the most common CNS lesion occurring in 43.7% (31/71) of the animals with CNS disease and 25% of all animals. The incidence of SIVE correlated significantly with shortened survival (P=0.0207). In addition, SIVE was seen in 42.9% (15/35) of rapid progressors (animals that died within 200 days) compared to only 18% (16/89) of normal progressors (animals that lived longer than 200 days) (P=0.011). Animals with SIVE had higher viral loads in peripheral blood than those that did not, but this difference did not reach statistical significance. Similarly, while animals infected with uncloned SIVmac251 had a higher incidence of SIVE (27.5%; 14/51) than animals infected with molecularly cloned SIVmac239 and its T-cell tropic derivatives (18.5%; 10/54) this difference was not statistically significant. In this study rapid disease progression and SIVE were highly correlated making separation of viral determinants of virulence from those of neurovirulence difficult.  相似文献   
66.
Recombinant human granulocyte colony-stimulating factor (G-CSF) at a dose of 1 to 300 micrograms/kg/day was administered intravenously to rats daily for 13 weeks. Serum alkaline phosphatase (ALP) activity increased dose-dependently with leukocytosis. Most of the increased leukocytes were segmented neutrophils, and neutrophil alkaline phosphatase (NAP) scores were elevated markedly. Serum ALP activity correlated very well with the segmented neutrophil counts, and the coefficient of correlation was more than 0.97 in both sexes. Pathological examinations revealed splenomegaly and a marked increase in neutrophils in the red pulp of the spleen. In the spleen, phagocytosis of neutrophils by macrophages was observed. These data indicate that the increased ALP was of neutrophil origin. Serum ALP activity may be increased by the direct release of ALP from the high number of neutrophils into the blood, or by the leakage of ALP into the blood mainly from the spleen where many neutrophils are pooled and destroyed by the macrophage system.  相似文献   
67.
Patients who undergo transplantation with haploidentical "three-loci" mismatched T-cell-depleted bone marrow (BM) are at high risk for graft failure. To overcome the host-versus-graft barrier, we increased the size of the graft inoculum, which has been shown to be a major factor in controlling both immune rejection and stem cell competition in murine models. Seventeen patients (mean age, 23.2 years; range, 6 to 51 years) with end-stage chemoresistant leukemia were received transplants of a combination of BM with recombinant human granulocyte colony-stimulating factor-mobilized peripheral blood progenitor cells from HLA-haploidentical "three-loci" incompatible family members. The average concentration of colony-forming unit-granulocyte-macrophage in the final inoculum was sevenfold to 10-fold greater than that found in BM alone. The sole graft-versus-host disease (GVHD) prophylaxis consisted of T-cell depletion of the graft by the soybean agglutination and E-rosetting technique. The conditioning regimen included total body irradiation in a single fraction at a fast dose rate, antithymocyte globulin, cyclophosphamide and thiotepa to provide both immunosuppression and myeloablation. One patient rejected the graft and the other 16 had early and sustained full donor-type engraftment. One patient who received a much greater quantity of T lymphocytes than any other patient died from grade IV acute GVHD. There were no other cases of GVHD > or = grade II. Nine patients died from transplant-related toxicity, 2 relapsed, and 6 patients are alive and event-free at a median follow-up of 230 days (range, 100 to 485 days). Our results show that a highly immunosuppressive and myeloablative conditioning followed by transplantation of a large number of stem cells depleted of T lymphocytes by soybean agglutination and E-rosetting technique has made transplantation of three HLA-antigen disparate grafts possible, with only rare cases of GVHD.  相似文献   
68.
Scaling of posturally stabilizing long latency (LL) reflexes in tibialis anterior muscles induced by "toe-up" rotational perturbations is abnormal in standing patients with Parkinson's disease. To investigate the contribution of dopaminergic pathways to abnormal scaling, we studied LL reflexes in 22 patients with selective hypodopaminergic syndromes: 10 psychiatric patients taking chronic neuroleptic medication (7 with mild parkinsonism), 8 patients with young-onset Parkinson's disease, and 4 patients with MPTP-induced parkinsonism. Results were compared with those of 10 healthy controls. Stimuli consisted of (a) 10 serial (predictable) perturbations of 4 degrees amplitude, (b) 10 serial (predictable) perturbations of 10 degrees amplitude, and (c) 20 randomly mixed (unpredictable) perturbations of either 4 or 10 degrees amplitude. In normal subjects, LL reflex amplitudes were adapted to match predictable variations in stimulus size, whereas under unpredictable conditions a "default" response emerged that anticipated the 10 degrees perturbation. LL reflex scaling under predictable conditions was intact in patients with neuroleptic-induced parkinsonism and young-onset Parkinson's disease, but the large default LL response under unpredictable conditions was absent. In patients with MPTP-induced parkinsonism, LL reflex scaling was absent during both predictable and unpredictable conditions. We conclude that abnormal scaling of posturally stabilizing LL reflexes is related to decreased supraspinal dopaminergic influence.  相似文献   
69.
PURPOSE: Interpretation time of serial staging chest CT cases, which each contained current and previous examinations, with a simple prototype workstation called filmstack was experimentally compared with interpretation time with a film alternator. MATERIALS AND METHODS: The filmstack displayed a "stack" of sections for each examination; user controls allowed rapid selection of preset attenuation windows and both synchronized and unsynchronized scrolling. Eight radiologists were timed as they used the filmstack and the film alternator to interpret four ergonomically complex serial CT cases. RESULTS: All reports dictated on the basis of findings with filmstack and film were of acceptable clinical accuracy. The time to examine a case with filmstack was significantly faster than the time with film, including the time to load and unload the alternator (99% confidence [P = .01]). There was no statistically significant difference in interpretation time between filmstack and prehung film. CONCLUSION: Use of a low-cost stacked CT workstation with a single 1,024 x 1,024 monitor is an effective means of interpreting cases that require comparison of multiple CT examinations.  相似文献   
70.
The comparative electrophysiological study of excitation process in heart with different types of organization have laid the foundation for solution of the problems of formation of cardioelectric field. It was shown, that the form of extracellular potentials on the epicardium correlated with different types of ventricle myocardial activation. Animals with the "flash" type of myocardial depolarization in most cases have the negative extracellular potentials in the greater part of the epicardial ventricular surface. Animals with the consecutive type of myocardial activation--the positive and biphase potentials. All myocardial layers (epicardial, intramural and endocardial) are electrophysiologically informative.  相似文献   
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