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111.
The emergence rate and adult survival (longevity) of Japanese strains of Culex pipiens molestus and Culex quinquefasciatus were compared at temperatures of 21, 25, and 30 degrees C. The pupation and emergence rates in both strains were higher at 21 and 25 degrees C than at 30 degrees C. The adult emergence rate, especially in females, was lower in Cx. p. molestus than in Cx. quinquefasciatus. Longevity of females and males was lower in Cx. p. molestus at 25 degrees C and above. The survival of Cx. p. molestus was adversely affected by temperatures of 28 degrees C and higher. High temperature may restrict the distribution of this species. Therefore, if Cx. p. molestus infests the Okinawa region, the likelihood that it will become established is minimal.  相似文献   
112.
Toborinone ((+/-)-6-[3-(3,4-dimethoxybenzylamino)-2-hydroxypropoxy]-2(1H)-qui nolinone, CAS 128667-95-8, OPC-18790), a novel cardiotonic agent with an inhibitory action on phosphodiesterase, is known to have a potent positive inotropic action with no positive chronotropic effect. The effectiveness of this drug in the treatment of heart failure occurring immediately after extracorporeal circulation (ECC) in cardiac surgery was investigated. The study was conducted in 12 patients with valvular heart disease showing a cardiac index (CI) of below 2.8 l/min/m2 and/or pulmonary capillary wedge pressure (PCWP) or pulmonary arterial diastolic pressure (PAD) of above 8 mmHg immediately after extracorporeal circulation. In group A (n = 6), toborinone was infused at a rate of 40 micrograms/kg/min for the first 5 min and then at 10 micrograms/kg/min for 85 min. In group B (n = 6), the drug was infused at a rate of 10 micrograms/kg/min for the entire 90 min. CI, mean systemic arterial pressure (mSAP), mean pulmonary artery pressure (mPAP), CVP, PCWP, and heart rate were measured at 5, 15, 30, 60, and 90 min after the start of infusion. The infusion volume required to maintain a constant PCWP was also estimated. In group A, CI increased rapidly and significantly from the baseline of 2.48 +/- 0.23 l/min/m2 to 3.57 +/- 1.07 l/min/m2 at 5 min after the start of infusion, and at that time mSAP was slightly decreased. In group B, CI increased gradually from the baseline of 2.53 +/- 0.18 l/min/m2 to 3.08 +/- 0.34 l/min/m2 at 15 min after the start of infusion, but almost no change was seen in mSAP. During the first 30 min, group A required a significantly larger infusion volume (983 +/- 395 ml) than group B (475 +/- 184 ml). From 30 to 90 min after the start of infusion, CI remained increased to similar levels in both groups and mSAP levels were also similar. There were no significant differences between the two groups in any other parameter. Continuous infusion of toborinone appears to be effective for treating heart failure occurring immediately after ECC in cardiac surgery. Initial loading at a rate of 40 micrograms/kg/min rapidly increased CI but was accompanied by mild hypotension. Constant infusion at 10 micrograms/kg/min brought about a more gradual effect that was similar to that of loading at 40 micrograms/kg/min, but without inducing hypotension. Thus, infusion at 10 micrograms/kg/min is considered preferable in order to avoid a larger-than-necessary infusion volume.  相似文献   
113.
The development of a new chemical entity for human use is a stepwise process based on an assessment of both animal and human data on efficacy and safety of the drug. Clinical pharmacologists always refer to animal data through an Investigator's Brochure (IB) when planning and performing a clinical trial(s). The IB should provide the investigator(s) with useful information to select doses, dosing intervals, and safety monitoring procedures and also to support the clinical management of subjects during the trial(s). Non-clinical animal studies contained in the IB, however, lack a relationship to the pharmacological and toxicological findings of the investigated product(s). Most of the non-clinical animal studies address the methodology and the results obtained, but are lacking in a discussion of the relevance of the findings. The IB should include not only a summary of the findings in each field of animal study but also relationships of the findings through some indicator(s) such as blood and tissue concentrations of the parent drug and/or metabolites. I do hope Pharmaceutical Companies will provide much useful information about their product(s) through the improvement of their system of research and development.  相似文献   
114.
The structure of antibiotic zelkovamycin was elucidated as a cyclic peptide comprising glycyl, 2-aminobutanoyl, 2-amino-2-butenoyl, N-methyl glycyl, alanyl, 1,3-thiazoyl, 7-methoxytryptophanyl and 2-methyldehydrothreonyl residues. The sequence of the amino acids was established by spectroscopic studies including 1H-1H COSY, 13C-1H COSY, 13C-1H HMQC, 13C-1H HMBC, 15N-1H HMQC and 15N-1H HMBC NMR experiments.  相似文献   
115.
We report herein the rare case of a 79-year-old man who suffered permanent paraplegia after undergoing an otherwise successful total arch replacement for a ruptured aortic arch aneurysm. During cardiopulmonary bypass, perfusion to the distal aorta was maintained from the femoral artery, and postoperative aortography showed intact tributaries from the aorta including the intercostal arteries. Postoperative paraplegia is an extremely rare complication of operations on the aortic arch; however, we speculate that the paraplegia in this patient could be attributed either to a steal phenomenon involving the radicular artery, or to the anatomical particularity of the spinal cord artery described by Cole and Gutelius as the segmental system.  相似文献   
116.
The significance of HLA-DRB1 matching in clinical renal transplantation.   总被引:2,自引:0,他引:2  
We analyzed the genotype for HLA-DRB1 alleles by digestion of polymerase chain reaction-amplified genes with the restriction endonucleases (PCR-RFLP) method to investigate the influence of HLA-DR antigen "splits" at the DRB1 gene level on the incidence of acute graft rejection in the renal transplant. For all patients, the incidence of acute rejection was proportional to the number of the serological HLA mismatch (0% in patients with two-haplotype match; 18% with HLA-A, -B, and -DR zero mismatch; 33% with HLA-DR zero mismatch; and 48% with HLA-DR one mismatch). For the patients with serological HLA-DR zero mismatch, the incidence of acute rejection in patients with HLA-DRB1 one mismatch (10/13: 77%) was significantly higher than that in those with zero mismatch (2/27: 7%). It was concluded that genotyping for HLA-DRB1 alleles would be beneficial in predicting acute rejection in patients with serological HLA-DR zero mismatch, although no difference was noted in the graft survivals.  相似文献   
117.
BACKGROUND: Prostate-specific membrane antigen (PSMA) is abundantly expressed in virtually 100% of prostate cancers and metastases. In addition, unlike prostate-specific antigen (PSA), PSMA is upregulated under conditions of androgen deprivation. Therefore, PSMA is an attractive therapeutic target for advanced prostate cancer. Recently, both the promoter and the enhancer driving prostate-specific expression of the PSMA gene were cloned. We describe here our analysis of the PSMA enhancer for the most active region(s) and present a way of using the enhancer in combination with the E. coli cytosine deaminase gene for suicide-driven gene therapy that converts the nontoxic prodrug 5-fluorocytosine (5-FC) into the cytotoxic drug 5-fluorouracil (5-FU) in prostate cancer cells. METHODS: Deletion constructs of the full-length PSMA enhancer were subcloned into a luciferase reporter vector containing either the PSMA or SV-40 promoter. The most active portion of the enhancer was then determined via luciferase activity in the C4-2 cell line. We then replaced the luciferase gene with the E. coli cytosine deaminase gene in the subclone that showed the most luciferase activity. The specificity of this technique was examined in vitro, using the prostate cancer cell line LNCaP, its androgen-independent derivative C4-2, and a number of nonprostatic cell lines. The toxicity of 5-FC and 5-FU on transiently transfected cell lines was then compared. RESULTS: The enhancer region originally isolated from the PSMA gene was approximately 2 kb. Deletion constructs revealed that at least two distinct regions seem to contribute to expression of the gene in prostate cancer cells, and therefore the best construct for prostate-specific expression was determined to be 1, 648 bp long. The IC(50) of 5-FC was similar in all cell lines tested (>10 mM). However, transfection with the 1648 nt PSMA enhancer and the PSMA promoter to drive the cytosine deaminase gene enhanced toxicity in a dose-dependent manner more than 50-fold, while cells that did not express the PSMA gene were not significantly sensitized by transfection. CONCLUSIONS: Suicide gene therapy using the PSMA enhancer may be of benefit to patients who have undergone androgen ablation therapy and are suffering a relapse of disease.  相似文献   
118.
119.
Ohkaya S  Hirata H  Uchida A 《Microsurgery》2000,20(3):126-130
We have found previously that expansion of the Wallerian degenerated nerve was accompanied by accelerated Schwann cell proliferation. In this study, we investigated the usefulness of the elongation of Wallerian degenerated nerve for the repair of short nerve gap. Male Wistar rats were used. After the left sciatic nerve was transected the rats were divided into 4 groups. In the control group, nerve coaptation was not performed. In group 1, tensionless coaptation was performed immediately. In group 2, delayed tensionless coaptation was performed with the elongation of Wallerian degenerated nerve. In group 3, coaptation was performed immediately with autologous interposition nerve graft. The ideal tensionless nerve repair of group 1 was considered to produce the best result. Rats in group 2 showed functional recovery as good as rats in group 1. On histologic assessment, in group 2, a fibrous capsule that was very rich in vascularity was formed around the tissue expander. After 14 weeks, the capsule was diminished markedly in size, but the vascularity was rich around the sciatic nerve. We think that the excellent functional recovery seen in group 2 can be attributed to the increased activity of Schwann cell proliferation and increased vascularity.  相似文献   
120.
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