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71.
Infiltration of esophageal epithelium by eosinophils is seen in reflux esophagitis and allergic gastroenteritis. This study was performed to identify differences between patients with acid reflux esophagitis and those with non-acid reflux, possibly allergic, esophagitis. Intraepithelial eosinophils were demonstrated in posttherapy esophageal biopsy specimens in 28 children treated for gastroesophageal reflux disease (GERD). These patients were divided into three groups based on their response to treatment and the results of esophageal pH probe monitoring. Eleven patients (Group A) had incomplete clinical response and normal pH probe monitoring results. Ten patients (Group B) had incomplete response but did not have pH probe monitoring. These two groups formed the index population. Seven patients (Group C) had clinical improvement with GERD therapy and abnormal pH probe monitoring characteristic of GERD; they constituted the control population. Clinical, laboratory, and pathologic features were evaluated to detect differences between index and control populations. Dysphagia, food impaction, failure to thrive, peripheral eosinophilia, and abnormal allergen skin test results were detected only in Group A and B patients. Biopsy specimens of the distal 9 cm of the esophagus, after GERD therapy, contained larger numbers of eosinophils in Groups A and B than in Group C as shown on high-power fields (HPF) (A: 31/HPF +/- 19.5; B: 28/HPF +/-23.7; versus C: 5/HPF +/-6.7; p = 0.009). Eosinophil aggregates were identified only in Groups A and B (p = 0.07). Eosinophils located preferentially in the superficial layers of the squamous epithelium were noted only in Groups A and B (p = 0.02). Group A and B patients demonstrated clinical improvement when given antiallergic therapy. The authors identified a group of pediatric patients characterized by an allergic history, lack of adequate response to GERD therapy, normal esophageal pH probe monitoring results, and large numbers of eosinophils in esophageal biopsy specimens obtained after GERD treatment. On the basis of these features, the authors propose that these patients represent examples of allergic esophagitis.  相似文献   
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74.
The article on the new drugs reprinted below appeared in the February 1956 issue of Mental Hospitals. It is based on a discussion held during the Seventh Mental Hospital Institute in October 1955 in Washington, D.C. Chlorpromazine and reserpine had been available in the United States less than two years when the institute participants met to discuss how their hospitals were coping with the demands of the new treatments. In a commentary and analysis beginning on page 333, Robert Cancro, M.D., considers the broader impact of the introduction of neuroleptics and examines the concerns of the 1956 institute participants in the context of today.  相似文献   
75.
Patients with psychiatric illnesses may be at higher risk for the development of certain medical problems. Those with more severe psychiatric illnesses may encounter barriers to promoting good health and to obtaining good health care when comorbid illnesses do occur. This paper reviews some of the recent literature on health care practices and health system access for the mentally ill; HIV care and its relationship to mental disorders; drug interactions between general medical drugs and psychotropics; and certain medical conditions that appear to co-occur more frequently with psychiatric disorders.  相似文献   
76.
Regarding the skull base, no structure is as centrally located as the sphenoid sinus. It sits at the junction of the anterior and middle cranial fossae, and is surrounded by vital structures. Although relatively rare, complications of the inflammatory and infectious conditions of sphenoid sinusitis are the result of direct extension of disease to the surrounding tissues, or a propagated thrombophlebitis through valveless veins, which connect the paranasal sinuses with the orbit, cavernous sinus, and intracranial cavity. The spread of inflammation and/or infection from the sphenoid sinus to the orbit and cavernous sinus causes 5 distinct clinical entities: (1) preseptal cellulitis, (2) orbital cellulitis, (3) subperiosteal abscess, (4) orbital abscess, and (5) cavernous sinus thrombosis. The list of possible intracranial complications of sphenoid sinusitis includes meningitis, skull base osteomyelitis, and epidural, subdural, or cerebral abscess. A high index of suspicion must accompany any patient with unresolving sinusitis, increasing or changing symptoms, including the development of visual changes, ophthalmoplegia, focal neurologic signs, seizures, mood alterations, or persistent headache despite adequate therapy. Early identification and therapeutic intervention for orbital and intracranial complications of sphenoid sinusitis are paramount to a favorable prognosis.  相似文献   
77.
Prior studies from this laboratory documented the prevalence of methotrexate (MTX) transport activity with a low pH optimum in human solid tumor cell lines. In HeLa cells, this low pH activity has high affinity for pemetrexed [PMX (Alimta)] and is reduced folate carrier (RFC)-independent because it is not diminished in a RFC-null subline (R5). R5 cells also have residual transport activity, with high specificity for PMX, at neutral pH. In the current study, a R5 subline, R1, was selected under MTX selective pressure at a modest reduction in pH. There was markedly decreased MTX and PMX transport at both pH 5.5 and pH 7.4. When MTX was removed, there was a slow return of transport activity, and when MTX was added back, there was loss of transport at both pH values within 8 weeks. In R1 cells, there was a marked decrease in accumulation of PMX, MTX, and folic acid along with a decrease in growth inhibition by these and other antifolates that require a facilitative process to gain entry into cells. These data demonstrate that (i) RFC-independent transport in HeLa cells at low and neutral pH contributes to antifolate activity (in particular, to PMX activity) and can be diminished by antifolate selective pressure and (ii) the loss of these activities results in marked resistance to PMX, an agent for which there is little or no loss of activity when transport mediated by RFC is abolished. These observations suggest that transport activity in RFC-null HeLa R5 cells at neutral and low pH may reflect the same carrier-mediated process.  相似文献   
78.
We assessed clinical results in 145 patients with chronic myeloid leukaemia in chronic phase who satisfied criteria for interferon-alpha failure and were thus eligible for treatment with imatinib at the Hammersmith Hospital. We used univariate and multivariate analyses to develop a risk score based on features defined after treatment for 3 months. We identified a low neutrophil count and poor cytogenetic response (<35% Ph-negative marrow metaphases) at 3 months as principal independent predictive factors and incorporated them into a three-tier prognostic scoring system for individual patients. For patients in the low-, intermediate- and high-risk groups, the probabilities of survival at 24 months were 100, 82 and 40% (P<0.0001) and progression-free survival 100, 66 and 15% (P<0.0001), respectively. This Hammersmith prognostic scoring system was validated with an independent cohort of patients treated at another UK centre.  相似文献   
79.
The purpose of this study was to further establish the efficacy of pedicle screw stimulation as a monitoring technique to avoid nerve root injury during screw placement. The study population consisted of 662 patients in whom 3,409 pedicle screws were placed and tested by electrical stimulation. If stimulation resulted in a myogenic response at a stimulation intensity of 10 mA or less, the placement of the screw was inspected. Inspection was necessary for 3.9% of the screw placements in 15.4% of the study population. None of the patients in the study experienced any new postoperative neurologic deficits. These findings provide guidelines for the interpretation of stimulation data and support the use of this technique as an easy, inexpensive, and quick method to reliably assess screw placements and protecting neurological function.  相似文献   
80.
Participation of patients 65 years of age or older in cancer clinical trials.   总被引:13,自引:0,他引:13  
PURPOSE: Although 61% of new cases of cancer occur among the elderly, recent studies indicate that the elderly comprise only 25% of participants in cancer clinical trials. Further investigation into the reasons for low elderly participation is warranted. Our objective was to evaluate the participation of the elderly in clinical trials sponsored by the National Cancer Institute (NCI) and assess the impact of protocol exclusion criteria on elderly participation. PATIENTS AND METHODS: We conducted a retrospective analysis using NCI data, analyzing patient and trial characteristics for 59,300 patients enrolled onto 495 NCI-sponsored, cooperative group trials, active from 1997 through 2000. Our main outcome measure was the proportion of elderly patients enrolled onto cancer clinical trials compared with the proportion of incident cancer patients who are elderly. RESULTS: Overall, 32% of participants in phase II and III clinical trials were elderly, compared with 61% of patients with incident cancers in the United States who are elderly. The degree of underrepresentation was more pronounced in trials for early-stage cancers than in trials for late-stage cancers (P <.001). Furthermore, protocol exclusion criteria on the basis of organ-system abnormalities and functional status limitations were associated with lower elderly participation. We estimate that if protocol exclusions were relaxed, elderly participation in cancer trials would be 60%. CONCLUSION: The elderly are underrepresented in cancer clinical trials relative to their disease burden. Older patients are more likely to have medical histories that make them ineligible for clinical trials because of protocol exclusions. Insurance coverage for clinical trials is one step toward improvement of elderly access to clinical trials. Without a change in study design or requirements, this step may not be sufficient.  相似文献   
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