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61.
S. Strauss J.Z. Jordens D. McBride C. Sonnex S. Edwards U. Desselberger P. Watt J.J. Gray 《European journal of epidemiology》1999,15(6):537-543
The prevalence of human papillomavirus (HPV) in paired cervical scrape and urine specimens from 144 women attending a clinic for genitourinary medicine was determined by polymerase chain reaction (PCR) and nested PCR, using degenerate and general primer pairs localized within the L1 region. HPV typing was by restriction fragment length polymorphism (RFLP), type-specific PCR (HPV 6, 11, 16, 18, 33), and partial DNA sequencing of PCR products. HPV DNA was detected in 114 (84%) women. HPV DNA was detected in the specimens of 58 patients after amplification with MY09/MY11 primers and in a further 54 patients after nested PCR with the GP5 + /GP6 + primers. A total of 106/136 (78%) of women had HPV DNA positive cervical scrapes and 89 (65%) had HPV DNA positive urine specimens. Both the urine and cervical specimens of 81 women were positive. In 25 women HPV DNA was detected in the cervical specimen only, and in 8 women HPV DNA was detected in the urine specimens only. A total of 108 specimens from 75 patients were typed. For 33 patients HPV typing was achieved in both the cervical and the urine specimens and 19 women had identical types in paired specimens. Multiple HPV infections could be detected in 15 (20%) of 75 women where either the cervical and urine specimen or both of the specimens could be typed. More then one HPV type was found in 8 specimens and from multiple sites (cervix and urinary tract) in the same patients on 7 occasions. The results of this study indicate that the detection of HPVs in the urogenital tract can be maximised through the testing of both cervical scrapes and urine specimens in conjunction with the use of a nested PCR to increase the sensitivity of HPV DNA detection. Also, urine cannot be a direct substitute for a cervical scrape as different HPV types are often detected in the urine compared with those detected in the cervix. 相似文献
62.
The Changing Landscape of Health Care Financing and Delivery: How Are Rural Communities and Providers Responding? 总被引:1,自引:0,他引:1
Mueller KJ Coburn A Cordes S Crittenden R Hart JP McBride T Myers W 《The Milbank quarterly》1999,77(4):485-510
Rural communities have not kept pace with the recent dramatic changes in health care financing and organization. However, the Medicare provisions in the Balanced Budget Act of 1997 will require rural providers to participate in the new systems. Case studies revealed the degree of readiness for change in six rural communities and charted their progress along a continuum, as reflected in three sets of activities: the development of networking; the creation of new strategies for managing patient care; and the adoption of new methods for contracting with health insurers. Some communities had constructed highly integrated systems, whereas others were just beginning to change their billing practices; a few were signing contracts for capitated care, in contrast to those that were resisting discounts in current fee structures. These six rural areas still have considerable ground to cover before their health care organization and financing reach the levels achieved by urban communities. 相似文献
63.
The purpose of this study was to determine the impact of secondary hypoxemia on visual discrimination accuracy after parasagittal fluid percussion injury (FPI). Rats lived singly in test cages, where they were trained to repeatedly execute a flicker-frequency visual discrimination for food. After learning was complete, all rats were surgically prepared and then retested over the following 4-5 days to ensure recovery to presurgery levels of performance. Rats were then assigned to one of three groups [FPI + Hypoxia (IH), FPI + Normoxia (IN), or Sham Injury + Hypoxia (SH)] and were anesthetized with halothane delivered by compressed air. Immediately after injury or sham injury, rats in groups IH and SH were switched to a 13% O2 source to continue halothane anesthesia for 30 min before being returned to their test cages. Anesthesia for rats in group IN was maintained using compressed air for 30 min after injury. FPI significantly reduced visual discrimination accuracy and food intake, and increased incorrect choices. Thirty minutes of immediate posttraumatic hypoxemia significantly (1) exacerbated the FPI-induced reductions of visual discrimination accuracy and food intake, (2) further increased numbers of incorrect choices, and (3) delayed the progressive recovery of visual discrimination accuracy. Thionine stains of midbrain coronal sections revealed that, in addition to the loss of neurons seen in several thalamic nuclei following FPI, cell loss in the ipsilateral dorsal lateral geniculate nucleus (dLG) was significantly greater after FPI and hypoxemia than after FPI alone. In contrast, neuropathological changes were not evident following hypoxemia alone. These results show that, although hypoxemia alone was without effect, posttraumatic hypoxemia exacerbates FPI-induced reductions in visual discrimination accuracy and secondary hypoxemia interferes with control of the rat's choices by flicker frequency, perhaps in part as a result of neuronal loss and fiber degeneration in the dLG. These results additionally confirm the utility of this visual discrimination procedure as a sensitive, noninvasive means of assessing behavioral function after experimental traumatic brain injury. 相似文献
64.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
65.
Radiation pneumonitis is a frequent complication of bone marrow transplantation. In limiting the effective dose that can be given, it decreases the chances of cancer cell destruction and of graft acceptance. The incidence of radiation pneumonitis is increased if graft-versus-host disease or infection is present, presumably due to an interaction between T-cell-mediated and radiation-mediated damage. Even in the absence of graft-versus-host disease and infection, we have found that syngeneic T-cells can contribute to radiation pneumonitis in a bone marrow transplant setting. The incidence of radiation pneumonitis was higher after whole-body irradiation and bone marrow transplantation than after whole-thorax irradiation. In the former situation, but not the latter, prior thymectomy decreased the incidence of radiation pneumonitis. It is hypothesized that autoreactive T-cells escape induction of self-tolerance during regression of the immune system after whole-body irradiation and, because autoregulatory cells are eliminated, they can contribute to radiation pneumonitis. If this concept is correct, it provides another possible explanation for the sensitivity of the lung to post-transplant pneumonitis and suggests new strategies to limit the incidence of this serious transplant-related complication. 相似文献
66.
This study is a review of literature on the factors affecting the retention and turnover of hospital consultants and midwives. While there is widespread concern and acknowledgement of staff retention problems for professional occupations within the NHS, far less research has analysed the causes of the staff retention problems for the occupations in question. This study shows that there is a dearth of literature in this area and that systematic comparative analysis of retention and turnover factors through both primary and secondary research is urgently required in order that policy-making can take place on the basis of informed choice. Tentative initial findings were that lack of appreciation or perceptions of not being valued are key factors influencing turnover for both occupations. Working hours, workload and work schedules are also common concerns to both groups. In addition, career development, promotion and appreciation of contribution were important retention factors for midwives, while a supportive professional environment, reduction in workload and working hours and more flexible work patterns were important to consultants. 相似文献
67.
Zachary A Rodd Richard L Bell Ying Zhang James M Murphy Avram Goldstein Alejandro Zaffaroni Ting-Kai Li William J McBride 《Neuropsychopharmacology》2005,30(2):330-338
The meso-limbic dopamine (DA) system has an important role in regulating alcohol drinking. Previous findings from our laboratory indicated that Wistar rats self-administered ethanol (EtOH) directly into the posterior, but not anterior, ventral tegmental area (VTA), and that coadministration of a DA D(2,3) receptor agonist or a serotonin-3 (5-HT3) receptor antagonist blocked EtOH self-administration. In addition, we reported that alcohol-preferring (P) rats self-administered acetaldehyde (ACD), the first metabolite of EtOH, into the posterior VTA. The objectives of this study were to compare the reinforcing effects of EtOH and ACD within the VTA of P rats to examine the possibility that the reinforcing effects of EtOH within the VTA may be mediated by its conversion to ACD. Adult female P rats were stereotaxically implanted with guide cannulae aimed at either the posterior or anterior VTA. At 1 week after surgery, rats were placed in standard two-lever (active and inactive) experimental chambers for a total of seven to eight sessions. The 4-h sessions were conducted every other day. The results indicated that (a) 75-300 mg% (17-66 mM) EtOH and 6-90 microM ACD were self-administered into the posterior, but not anterior, VTA; (b) the self-administration of 150 mg% EtOH was not altered by coinfusion of a catalase inhibitor; (c) coadministration of the D(2/3) agonist quinpirole (100 microM) blocked the self-infusions of 150 mg% EtOH and 23 microM ACD into the posterior VTA; and (d) coadministration of 200 microM ICS205,930 (5-HT3 receptor antagonist) prevented the self-infusion of 150 mg% EtOH, whereas concentrations of ICS 205,930 up to 400 microM had no effect on the self-infusion of 23 microM ACD into the posterior VTA. Overall, the results of this study indicate that EtOH and ACD can independently produce reinforcing effects within the posterior VTA, and that activation of DA neurons mediates these effects. Furthermore, activation of 5-HT3 receptors within the posterior VTA is involved in the self-infusion of EtOH, but not ACD. 相似文献
68.
A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed. 相似文献
69.
70.