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91.
Recombinant human interleukin-1 alpha (rIL-1 alpha), at concentrations that were not growth-inhibitory when given alone (100-10,000 U/ml), enhanced the growth inhibition resulting from a 72-h fluorouracil (FUra) exposure in HCT116 colon cancer cells. Median-effect analysis of clonogenic assays indicated that rIL-1 alpha, given 24 h prior to and following a 24-h exposure to FUra, increased lethality in a more than additive fashion. rIL-1 alpha did not appear to significantly affect [3H]-FUra metabolism, total [3H]-FUra-RNA incorporation or RNA retention after drug removal, inhibition of thymidylate synthase, or thymidine triphosphate pool depletion. During continuous exposure to rIL-1 alpha, transient stimulation of RNA and DNA synthesis was observed at 72 h, with a return to normal by 96 h. A 24-h exposure to 10 microM FUra altered the elution profile of newly synthesized DNA as monitored by pH step alkaline elution. An accumulation of lower-MW single-stranded DNA species was noted with FUra compared to control, accompanied by a significantly decreased proportion of DNA retained on the polycarbonate filter: 10% retained vs. 32% for control (P = 0.01). A 48-h exposure to rIL-1 alpha alone did not affect the elution profile of nascent DNA species, nor did it enhance the effects of FUra. Although FUra did not appreciably affect pulse [3H]-uridine incorporation into RNA for the initial 8-24 h of FUra exposure, progressive inhibition of net RNA synthesis was observed thereafter. FUra prevented the stimulatory effect of rIL-1 alpha on RNA synthesis, and net RNA synthesis was significantly inhibited (by 64-79% after 72 and 96 h) with the combination compared to rIL-1 alpha alone. Continuous exposure to 10 microM thymidine did not rescue cells from the lethality of FUra alone or the combination of FUra plus rIL-1 alpha, suggesting that depletion of deoxythymidine triphosphate as a consequence of thymidylate synthase inhibition was not the most important component of FUra toxicity. In contrast, 1 mM uridine provided partial protection against the toxicity of FUra alone or with rIL-1 alpha. Although uridine did not affect FUra metabolism, it decreased FUra-RNA incorporation by 42-60%, presumably as a consequence of the 2-fold expansion of UTP pools. [125I]-rIL-1 alpha binding was nonspecific; with a 24-h exposure, however, internalized [125I]-rIL-1 alpha exceeded cell surface-bound material by 2-fold.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
92.
Associations of sexual assault history with multiple measures of physical health were examined among 1,610 randomly selected women living in Los Angeles, California. Sexually assaulted women were more likely than nonassaulted women to report poor health perceptions, functional limitation, several chronic diseases, medically explained somatic symptoms, and medically unexplained somatic symptoms. Sexual assault was associated with increased risk of symptoms in a variety of organ systems rather than solely reproductive or sexual symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
We have investigated factors influencing the survival of women with early breast cancer in Scotland. In a retrospective study, clinical, treatment and 'service' factors, e.g. surgical case load, deprivation and geographical area (health board of first treatment) were recorded from hospital records. A total of 2148 women with invasive breast cancer diagnosed in 1987 were identified from the Scottish Cancer Registry, of whom 1619 without metastases at diagnosis underwent surgery as part of their primary treatment. In a multivariate analysis, clinical factors (age, clinical stage, pathological tumour size, node status and oestrogen receptor status) all influenced survival. After allowing for these clinical factors, surgical case load and deprivation did not have statistically significant effects on survival. By contrast, health board did affect survival. This was explained in part by the selection of patients for surgery. There appeared, however, to be a residual effect that may be related to differences in the use of adjuvant systemic treatment among the different health boards. We conclude that, in Scotland, geographical variation in both surgical and non-surgical treatment has a greater effect on variability in survival for women with breast cancer than surgical case load and deprivation.  相似文献   
94.
We describe a 32 year old male with a distal 6p24.3-->pter deletion. He has specific developmental anomalies of the anterior chamber of the eye and a cleft uvula which is consistent with the recent localisation of genes for iris development and orofacial clefting to distal 6p. In addition he has progressive sensorineural deafness and this may localise a gene for deafness to this region. We conclude that a refined distal 6p deletion syndrome exists and includes a characteristic facial appearance with hypertelorism, downward slanting palpebral fissures, tented mouth, smooth philtrum, palatal malformation, ear anomalies, anterior chamber eye defects, progressive sensorineural deafness, cardiac defects, abdominal herniae, small external genitalia, and motor and speech delay.  相似文献   
95.
96.
The purpose of this study was to investigate platelet effects on postischemic heart function in conjunction with adenosine effects on intracoronary platelet adhesion. Homologous platelets were infused into the coronaries of isolated guinea pig hearts, either during low-flow ischemia or during reperfusion, and external heart work (EHW) and intracoronary platelet adhesion were determined. In most experiments, thrombin was added to the perfusate. The influence of endogenous adenosine was studied by use of the uptake blocker dipyridamole and the unspecific adenosine-receptor blocker theophylline, the A1-receptor blocker 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), and the A2-receptor blocker 3,7-dimethyl-1-propargylxanthine (DMPX). The importance of nitric oxide and prostaglandin I2 (PGI2) was tested by using nitro-L-arginine (NOLAG) and indomethacin, respectively. When platelets were applied with thrombin during low-flow ischemia, EHW recovered to only 63 +/- 4% of the preischemic value, as compared with 89 +/- 3% without platelets (p < 0.05). Despite thrombin, platelets incurred no significant functional loss when applied in the first minute of reperfusion (but again in the fifth minute); however, when theophylline was also present, recovery of EHW amounted to only 42 +/- 12%. Intracoronary adhesion of platelets was negligible without thrombin, and highest during low-flow ischemia with thrombin (35 +/- 3% of the applied number). No adhesion occurred during the first minute of reperfusion, whereas in the fifth minute, adhesion was again 20.8 +/- 4%. Dipyridamole increased adenosine release and attenuated adhesion at this time. Theophylline increased adhesion in the first minute of reperfusion (33 +/- 6.4%), whereas NOLAG and indomethacin proved to be ineffective. DPCPX and DMPX each increased platelet retention during the first minute of reperfusion, their effects being additive. Intracoronary adhesion of platelets induced by thrombin in isolated hearts can reduce postischemic recovery of heart function. During reperfusion, but not during low-flow, endogenous adenosine can prevent platelet adhesion and loss of myocardial function, an action mediated both by A1- and A2-receptor-dependent mechanisms.  相似文献   
97.
98.
The propagation of recombinant plasmids in bacterial hosts, particularly in Escherichia coli, is essential for the amplification and manipulation of cloned DNA and the production of recombinant proteins. The isolation of bacterial transformants and subsequent stable plasmid maintenance have traditionally been accomplished using plasmid-borne selectable marker genes. Here we describe a novel system that employs plasmid-mediated repressor titration to activate a chromosomal selectable marker, removing the requirement for a plasmid-borne marker gene. A modified E.coli host strain containing a conditionally essential chromosomal gene (kan) under the control of the lac operator/promoter, lac O/P, has been constructed. In the absence of an inducer (allolactose or IPTG) this strain, DH1 lackan , cannot grow on kanamycin-containing media due to the repression of kan expression by LacI protein binding to lac O/P. Transformation with a high copy-number plasmid containing the lac operator, lac O, effectively induces kan expression by titrating LacI from the operator. This strain thus allows the selection of plasmids without antibiotic resistance genes (they need only contain lac O and an origin of replication) which have clear advantages for use as gene therapy vectors. Regulation in the same way of an essential, endogenous bacterial gene will allow the production of recombinant therapeutics devoid of residual antibiotic contamination.  相似文献   
99.
In April and May 1996, two cases of PDA ligation were performed firstly in Turkey by the method of video assisted thoracoscopic surgery (VATS) in Dokuz Eylül Medical Faculty, Thoracic and Cardiovascular Surgery Department. There was not any complication in these patients in the postoperative period and they were discharged on the second day in symptom-free condition by the detection of closed ductus in their echocardiographic examination. Between February 1993 and October 1996, a total of 46 patients have undergone interventional application by VATS. While in six of these patients the procedure could not be manipulated because of massive pleural fibrosis, there was no mortality or morbidity among the patients, and they were discharged on average on the second day. The ratio of complications, such as bleeding, air leak, arrhythmia and empyema are so low in these operations, and hospital stay, with return to work time are shorter than with the open technique.  相似文献   
100.
The authors have designed and constructed a plant-optimize synthetic gene encoding the Escherichia coli heat-labile enterotoxin B subunit (LT-B), for use in transgenic plants as an edible vaccine against enterotoxigenic E. coli. Expression of the synthetic LT-B gene in potato plants under the control of a constitutive promoter yielded increased accumulation of LT-B in leaves and tubers, as compared to the bacterial LT-B gene. The plant-derived LT-B assembled into native pentameric structures as evidenced by its ability to bind ganglioside. The authors demonstrated immunogenicity by feeding mice the raw tubers and comparing the anti-LT-B serum IgG and faecal IgA to that produced in mice gavaged with bacterial LT-B. Mice were fed three weekly doses of 5 g tuber tissue containing either 20 or 50 micrograms LT-B, or gavaged weekly with 5 micrograms of LT-B from recombinant E. coli. One week after the third dose, mice immunized with potato LT-B had higher levels of serum and mucosal anti-LT-B than those gavaged with bacterial LT-B. Mice were challenged by oral administration of 25 micrograms LT, and protection assessed by comparing the gut/carcass mass ratios. Although none of the mice were completely protected, the higher dose potato vaccine compared favourably with the bacterial vaccine. These findings show that an edible vaccine against E. coli LT-B is feasible.  相似文献   
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