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31.
Spontaneous thioguanine-resistant mutants were derived from populations of finite-life-span, diploid human fibroblasts by means of a fluctuation analysis. cDNA was prepared from mutantHPRT mRNA and amplified by the polymerase chain reaction, and the sequence of the product was analyzed. Exon deletions, which very likely arose from mutations in the intron splice site consensus sequences, were found in 10 of the 37 mutants examined (27% of the total). Among the 28 mutations in the coding sequence, base pair substitutions predominated (89%). With the exception of one base pair involved in a tandem mutation, all base pair substitutions resulted in alterations in the predicted amino acid sequence of the protein. In addition there were three frameshift mutations, consisting of the deletion of one or two base pairs. Although mutations occurred throughout the coding sequence, 50% (14/28) were found in the 5 portion of exon 3.  相似文献   
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"Working for Patients', the government's review of the National Health Service (NHS) advocates reforms which have led inevitably to pressure for medical specialities to review both the outcomes of their services and the resources used in achieving these outcomes. This paper considers these issues in the context of provision of palliative radiotherapy for patients with incurable cancers and presents the results of a study which evaluated the costs of radiotherapy. In addition to producing some of the first detailed cost estimates for the delivery of radiotherapy, this exercise highlighted the methodological and practical difficulties of undertaking such studies. As increasing pressure to evaluate cancer therapy is a prominent feature of a 'post-NHS Review' world, lessons learnt from this study may also be applicable to the audit of other cancer therapies. Efficient audit practices will, of course, have to evaluate the benefits (in terms of enhancements to length and quality of life) as well as the costs of cancer therapies.  相似文献   
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Changes in serum zinc and copper levels were studied in 19 tumor bearing patients undergoing parenteral nutrition (TPN) for five to 42 days. Before initiation of intravenous feeding mean serum zinc and copper concentrations were within normal limits but during TPN levels decreased significantly below those measured prior to parenteral nutrition. During TPN nitrogen, zinc, and copper intake, urinary output and serum levels were studied prospectively in nine of these patients. These nine patients exhibited positive nitrogen retention based upon urinary nitrogen excretion, but elevated urinary zinc and copper excretion and lowered serum zinc and copper concentrations. Neither blood administration nor limited oral intake was consistently able to maintain normal serum levels of zinc or copper. Zinc and copper supplementation of hyperalimentation fluids in four patients studied for five to 16 days was successful in increasing serum zinc and copper levels in only two. The data obtained suggest that patients undergoing parenteral nutrition may require supplementation of zinc and copper to prevent deficiencies of these elements.  相似文献   
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Systematic disinfection of the stethoscope diaphragm is required to ensure that it does not act as a vector for cross-transmission of health-related diseases. Thus, an antimicrobial latex film could be used as a cover to inhibit pathogenic bacteria from growing on its surface. The aim of this work is to determine the antimicrobial activity and mechanical properties of antimicrobial natural rubber (NR) latex films with different types of antimicrobial agents (mangosteen peel powder (MPP), zinc oxide nanoparticles (ZnO NP), and povidone-iodine (PVP-I)). The antimicrobial loading was varied from 0.5, to 1.0, and 2.0 phr to monitor the effective inhibition of Gram-negative bacteria and fungi growth. For MPP and PVP-I antimicrobial agents, a loading of 2.0 phr showed good antimicrobial efficacy with the largest zone of inhibition. Simultaneously, ZnO NP demonstrated excellent antimicrobial activity at low concentrations. The addition of antimicrobial agents shows a comparable effect on the mechanical properties of NR latex films. In comparison to control NR latex film (29.41 MPa, 48.49 N/mm), antimicrobial-filled films have significantly greater tensile and tear strengths (MPP (33.84 MPa, 65.21 N/mm), ZnO NP (31.79 MPa, 52.77 N/mm), and PVP-I (33.25 MPa, 50.75 N/mm). In conclusion, the addition of antimicrobial agents, particularly ZnO NP, can be a better choice for NR latex films because they will serve as both an activator and an antimicrobial. In a clinical context, with regard to frequently used medical equipment such as a stethoscope, such an approach offers significant promise to aid infection control.  相似文献   
37.
STUDY OBJECTIVE: To determine whether use of heated humidified carbon dioxide as insufflation gas during gynecologic laparoscopy reduced postoperative pain and hypothermia. DESIGN: A randomized controlled trial (Canadian Task Force classification 1). SETTING: A tertiary referral hospital. PATIENTS: Sixty women scheduled for gynecologic laparoscopy between 30 and 90 minutes' duration. INTERVENTIONS: Operative laparoscopic management of endometriosis, adhesions, or adnexal pathology. MEASUREMENTS AND MAIN RESULTS: Sixty patients were randomized into either receiving heated humidified carbon dioxide (study group) or standard cold dry gas (control group). Intraoperative and postoperative core temperature, total analgesic use, postoperative nausea, and recovery room time were recorded. Postoperative pain intensity was assessed using visual analog scale. Statistical analysis was performed using software. No significant difference was revealed between groups with regard to postoperative pain, analgesic requirements, recovery room time, or postoperative nausea. The control group had less postoperative hypothermia, suggesting that external warming blankets may be more effective than heated humidified gas at maintaining intraoperative normothermia. CONCLUSION: The use of heated humidified carbon dioxide insufflation for short-duration gynecologic laparoscopy up to 90 minutes' duration was not associated with any significant benefit with regard to postoperative pain, hypothermia, or time of recovery room stay.  相似文献   
38.
We describe our experience of over 300 cycles of preimplantation genetic diagnosis (PGD) and report clinical pregnancy rates (35%-67%) that support using this technology to screen for genetic disorders and chromosomal abnormalities. In clinical practice for over ten years, PGD offers couples the earliest form of genetic screening and may help improve ongoing pregnancy rates in poor-prognosis patients.  相似文献   
39.
Grapevine red blotch disease emerged within the past decade, disrupting North American vine stock production and vineyard profitability. Our understanding of how grapevine red blotch virus (GRBV), the causal agent of the disease, interacts with its Vitis hosts and insect vector, Spissistilus festinus, is limited. Here, we studied the capabilities of S. festinus to transmit GRBV from and to free-living vines, identified as first-generation hybrids of V. californica and V. vinifera ‘Sauvignon blanc’ (Vcal hybrids), and to and from V. vinifera ‘Cabernet franc’ (Vvin Cf) vines. The transmission rate of GRBV was high from infected Vcal hybrid vines to healthy Vcal hybrid vines (77%, 10 of 13) and from infected Vvin Cf vines to healthy Vcal hybrid vines (100%, 3 of 3). In contrast, the transmission rate of GRBV was low from infected Vcal hybrid vines to healthy Vvin Cf vines (15%, 2 of 13), and from infected Vvin Cf vines to healthy Vvin Cf vines (19%, 5 of 27). No association was found between transmission rates and GRBV titer in donor vines used in transmission assays, but the virus titer was higher in the recipient leaves of Vcal hybrid vines compared with recipient leaves of Vvin Cf vines. The transmission of GRBV from infected Vcal hybrid vines was also determined to be trans-stadial. Altogether, our findings revealed that free-living vines can be a source for the GRBV inoculum that is transmissible by S. festinus to other free-living vines and a wine grape cultivar, illustrating the interconnected roles of the two virus hosts in riparian areas and commercial vineyards, respectively, for virus spread. These new insights into red blotch disease epidemiology will inform the implementation of disease management strategies.  相似文献   
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