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101.
We sought to determine the incidence of infection with hepatitis B virus (HBV) amongst hospital employees over a 10-year period and to assess the extent and efficacy of vaccination against HBV in this population. In 1984 a cohort of 301 hospital employees was tested for hepatitis B surface antibody (anti HBs), hepatitis B core antibody (anti HBc), and hepatitis B surface antigen (HBsAg). Ten years later, 160 (53%) of these workers remained at the hospital and were re-tested. In addition, they were tested for hepatitis C virus antibody (anti HCV). Records of the hospital vaccination program were inspected to determine the rate and effectiveness of vaccination in these workers. Over the ten year period two of the 160 retested workers (1.25%) had sero-converted to anti HBc positive, yielding an incidence density of 0.27 cases per 100 person-years exposed in unvaccinated workers. While the overall seroprevalence of anti HBc did not change significantly between 1984 (81/301, 27%) and 1994 (39/160, 24%), it was much greater than that of the general population (10%). A significantly greater percentage of Jews of Sephardi ancestry (22/65, 34%) were positive for anti HBc than those of Ashkenazi ancestry (15/90, 17%, P < 0.05). In addition, doctors were found to be less likely to be anti HBc positive than nurses (4% vs. 25%, respectively, P < 0.01). Two cases of anti HCV positivity were discovered yielding a prevalence of 1.25% in the 1994 cohort as compared to 0.15% in the population of healthy blood donors. Of the 93 employees of the 1994 cohort eligible for vaccination (i.e., anti HBc-negative and employed in an occupation involving potential exposure to HBV), 53 (57%) had received vaccination and showed protective antibody titers (anti HBs > or = 10 i.u./ml). 17/52 workers with documented vaccinations (33%) did not have detectable antibody levels one to eight years after vaccination. In conclusion, the seroprevalence of anti HBc and anti HCV is significantly higher in this cohort of hospital employees than in the general population. The relatively low vaccination rate among at-risk personnel emphasizes the need for more effective vaccination programs.  相似文献   
102.
Clinical governance is being led by two people, usually a GP and a nurse, in most of the PCGs that responded to the survey. A fifth of the leads for clinical governance had no experience of working on quality issues. Nearly a third of respondents felt that their health authority had provided poor support or none at all. Only 10 PCGs had identified a clinical governance budget. No PCG was working with a finance manager to develop clinical governance and only five were working with an information manager.  相似文献   
103.
104.
PURPOSE: To present a case demonstrating progression of retinal nerve fiber myelin and to suggest that myelinated retinal nerve fibers be considered among the peripapillary choristomas. METHOD: Case report. A 46-year-old woman demonstrated progression of myelinated retinal nerve fibers and associated retinal vascular anomalies. RESULTS: Myelinated retinal nerve fibers can be progressive. We confirm earlier reports of vascular anomalies associated with retinal nerve fiber myelin and show that they can also be progressive. CONCLUSIONS: The rarely progressive nature of myelinated retinal nerve fibers and the histopathologic studies published to date suggest that myelinated retinal nerve fibers represent a striking ophthalmoscopic feature resulting from ectopic oligodendrocytes; thus, the entity may be described as an oligodendrocytic choristoma.  相似文献   
105.
We sought to test the response of the coronary microcirculation to alpha-adrenoceptor blockade in patients with syndrome X (angina, ischemia-like stress electrocardiogram, and a normal coronary arteriogram). The response of the microcirculation was assessed by quantification of coronary vasodilator reserve (the ratio of hyperemic to resting myocardial blood flow). We investigated 28 patients with syndrome X [18 women, age 54.4 (7.6) years]. Myocardial blood flow was measured at rest and after dipyridamole by using positron emission tomography with H(2)15O. The measurements were made before and after treatment for 10 days with doxazosin (1 mg o.d. for 3 days, followed by 2 mg o.d. for 7 days) or a matched placebo, similarly administered. Patients were randomized to alpha1-blockade or to placebo in double-blind fashion. No significant differences were demonstrable between syndrome X patients treated with doxazosin and those receiving placebo, with respect to resting myocardial blood flow, myocardial blood flow after dipyridamole, or coronary vasodilator reserve (the ratio of the latter two). In addition, no relations were demonstrable among myocardial blood flow, coronary vasodilator reserve, development of chest pain after dipyridamole, or development of ischemia-like ECG changes. Doxazosin had no effect on the perception of chest pain after dipyridamole. No differences were found between the effects of alpha1-blockade with doxazosin or those of placebo with respect to myocardial blood flow in syndrome X. The values obtained for myocardial blood flow and coronary vasodilator reserve for the patients were within the normal range. The data do not support the case for alpha1-mediated vasoconstriction having an etiologic role in the chest pain of syndrome X.  相似文献   
106.
Patients with X-linked Ig deficiency with normal or elevatedIgM (HIGMX-1) fail to switch from IgM/IgD to other Ig isotypes.Interaction between the B cell antigen CD40 and the CD40 ligandexpressed on activated T cells is critical for T cell drivenisotype switching. We have reported that T lymphocytes fromthree unrelated male patients with HIGMX-1 failed to expressCD40 ligand on their surface, but the mRNA for CD40 ligand wasof an apparently normal size and level. Analysis of CD40 ligandcDNA from two of the patients revealed deletions that alterthe reading frame. Patient 1 displayed two mutations: a C Atransversion at nucleotide 590 and the deletion of an adjacentC nucleotide. The second patient had a 58 bp deletion from nucleotides289–346. Furthermore, neither patient expressed a proteinproduct detectable by the CD40L mAb, 5c8.  相似文献   
107.
Seventy-two asymptomatic, postmenopausal women treated with tamoxifen for breast cancer were studied prospectively with vaginal ultrasonography, followed by endometrial sampling. Seventy-one patients demonstrated an endometrial echo of more than 5 mm, and one displayed an endometrial echo of less than 5 mm. No patient with an endometrial echo of less than 5 mm displayed any endometrial pathology. Different endometrial pathologic conditions were found when the endometrial echo was over 5 mm. When classifying those patients whose ultrasonic endometrial widths were wider than 5 mm, on the basis of different endometrial histologic findings, no obvious correlation was found between the various pathologic endometrial findings and endometrial thickness. Thus, a "thicker" endometrial sonographic image did not necessarily correlate with pathologic endometrial findings. When ultrasonic endometrial thickness of 5 mm was considered the upper limit of normal, the sensitivity of ultrasonography in correlating to positive histologic findings was 91% and the specificity was 96%. These findings suggest that there is good correlation between endometrial width measured by ultrasonographic assessment and histologic findings.  相似文献   
108.
Current methods of peripheral nerve repair are to directly suture cut nerve stumps, or to bridge large gaps with an autograft repair. Autograft-associated problems include donor site morbidity and limited supply. Many of the present limitations of nerve repair might be overcome by expanding the patients own Schwann cells in vitro, then combining the cells with other neuro-tropic and -trophic materials into an Artificial Nerve Graft (ANG) for bridging a nerve gap. In this 4.5 month experiment, a rat peroneal nerve model with a 10 mm gap was used to evaluate the effect of live Schwann cells on peripheral nerve regeneration. Nerve gaps were repaired with cellular ANGs containing live Schwann cell, dead Schwann cell, or mixed fibroblast/Schwann cell populations suspended in a collagen I matrix, and with sutured autografts or ANGs containing just collagen or medium. Regenerated nerves were evaluated by walking track analysis, qualitative and quantitative histology, and electrophysiology. Overall, the autograft was the best repair method, while the ANG containing live Schwann cells was statistically superior to other ANG repair methods. This study demonstrates that an ANG containing cultured syngeneic Schwann cells improves functional, histological, and electrophysiological parameters of peripheral nerve regeneration.  相似文献   
109.
Although physical restraint is a widely used and possibly hazardous form of treatment, few guidelines for its use appear in the recent psychiatric literature. An approach is described in which physical restraint is considered to be a specific therapeutic technique with definable indications, "dosages", contra-indications, and side effects. A method of initiating and terminating this treatment modality is presented and the indications for its use are discussed. These include the presence of violent behavior during a psychotic illness; the presence of agitation or confusion when the use of antipsychotic medication is limited by physical illness; the presence of severe psychotic symptoms in conjunction with severely regressed, socially aversive behavior; the need to reduce excessive external stimuli; and the request for restraint by the patient. Possible side effects and contra-indications are also discussed and criteria for evaluating the duration and effectiveness of the treatment are proposed.  相似文献   
110.
Twenty previously untreated children with primary Ewing's sarcoma and 8 children with primary tumor and metastatic disease were treated with surgery or radiation therapy (6,000-7,000 rads) for their primary tumor and T-2 chemotherapy. Of the 20 children with primary Ewing's sarcoma treated with T-2 "adjuvant" chemotherapy, 15 had no evidence of recurrent disease for from 31+-82+ months (median 46+ months) from the start of treatment. The actuarial 5-year disease-free survival rate for this group of patients was 75%. Eight patients presenting with metastatic disease had complete responses to T-2 chemotherapy, but 7/8 with metastatic disease eventually had tumor recurrence. Examination of the treatment failures, both those patients relapsing after adjuvant chemotherapy for primary Ewing's sarcoma (5), and those relapsing after having a complete response of metastatic disease (7) to T-2 chemotherapy, revealed that all relapses occurred at the end of the second year of T-2 chemotherapy or after chemotherapy was stopped. In addition, of 23 patients receiving "curative" radiation therapy to their primary tumor, 5 had local recurrence (22%) and 6 (26%) had severe functional debility secondary to combined radiation therapy and T-2 chemotherapy. The conclusions drawn from this experience have led us to consider a new approach to the treatment of Ewing's sarcoma, namely: 1) more aggressive initial or "induction" chemotherapy with subsequent T-2 "maintenance" chemotherapy to eradicate more completely all metastatic microfoci of disease presumed to be present in patients with primary tumor at the time of diagnosis, and ostensively present in patients with metastatic disease; 2) the use of surgery alone or in combination with moderate doses of radiation therapy in those patients in whom we can predict a high frequency of local recurrence (pelvic lesions) or a high percentage of "functional failures" (young children with lower extremity lesions). Preliminary results with this latter approach are encouraging with 11/13 patients with primary Ewing's sarcoma free of disease at 12+-26+ months. A longer follow-up of this more aggressive treatment is needed to determine the superiority of this approach for both increased survival and improved late physical rehabilitation.  相似文献   
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