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71.

Tobacco use remains the leading cause of preventable disease and death in the US. The number of tobacco products has grown over the past decade. E-cigarette use has increased rapidly in recent years, but patterns and correlates of use have not been thoroughly assessed. We examined relationships among demographic factors, e-cigarette and conventional cigarette use in a large sample (N?=?12,409) of adult patients at a community health center in the Northeastern US. Overall, 13% (N?=?1675) of the sample reported ever using e-cigarettes. In logistic regression models, ever having used e-cigarettes was associated with younger age (ages 18–25; OR?=?3.5, p?<?0.001). Being transgender (OR?=?1.8, p?<?0.001), bisexual (OR?=?1.5, p?<?0.001), un-partnered (OR?=?1.5, p?<?0.001), having a lower income (OR?=?1.6, p?<?0.001) or a high BMI (OR?=?1.4, p?=?0.009) were associated with increased odds of use, whereas being a woman (OR?=?0.7, p?<?0.001) or Black/African American (OR?=?0.7, p?=?0.007) were associated with lower odds of use. Of the participants who reported e-cigarette use, a majority also endorsed current or former use of conventional cigarettes. Individuals who formerly used conventional cigarettes were nearly three times more likely to report daily e-cigarette use than current users. Among primary care patients at a community health center, e-cigarette use was reported by a sizeable portion of the sample. Overall, odds of use were higher in certain patient populations, and individuals who formally used cigarettes were more likely to report e-cigarette use than individuals who currently smoke, suggesting that e-cigarettes may be functioning as a cessation aid or a strategy to reduce conventional cigarette use.

  相似文献   
72.
Objective: Children with special health care needs are increasingly enrolling in managed care arrangements. However, existing managed care organizations, including traditional HMOs, are often poorly suited for caring for this population. In the adult health care area, new managed care entities, called Social HMOs (S/HMO) and Programs for the All-inclusive Care for the Elderly (PACE), have been created to integrate health and health-related services for chronically ill and disabled adults. We describe these models and assess their potential for serving children with special health care needs. Method: We reviewed the literature on managed care for children with special health care needs and evaluation findings from the S/HMO and PACE models for the elderly. Results: Evaluations of the S/HMO and PACE models have yielded mixed findings. Some of the more positive accomplishments include lower use and expenditures for long-term care services compared to other demonstration projects, greater integration of primary care physicians in decision making concerning long-term care, and improved management of transitions between care levels. On the negative side, start-up has been slow, prospective members have been hesitant to enroll, intermittent and sometimes frequent operating deficits have emerged, no discernible positive effects on health or social outcomes are apparent, and no significant overall savings have emerged. Conclusions: With mixed results so far, caution is required in applying these or similar models for vulnerable child populations. However, given the inadequacies of traditional managed care for this population, we believe experimentation with new models of care that integrate health and health-related services is important. Such experimentation should be fostered only to the extent that the models are carefully designed and then implemented in a manner that protects the interests of children with special health care needs.  相似文献   
73.
Summary Previously we have demonstrated that the L1210 antitumor activity of liposomal doxorubicin increased significantly as the size of the liposomal carrier was reduced from 1.0 to 0.1 m. It is demonstrated herein that empty and drug-loaded small (0.1-m diameter) liposomes accumulate efficiently into the peritoneal cavity of normal and ascitic L1210 tumor-bearing animals following i.v. administration. In normal mice injected with 100 nm DSPC/chol liposomal doxorubicin (drug-to-lipid ratio of 0.2; wt/wt) approximately 2.8 g drug could be recovered from the peritoneal cavity following peritoneal lavage at 24 h. Although this represents only 0.7% of the injected doxorubicin dose, this level of drug is 2 orders of magnitude greater than that achieved following administration of an equivalent dose of free drug (20 mg/kg). The drug levels achieved within the peritoneal cavity are dependent on the physical characteristics (size, drug-to-lipid ratio and lipid composition) of the liposomes employed. Optimal delivery is obtained employing 100 nm DSPC/chol liposomal doxorubicin, a vesicle system that is known to retain entrapped drug following i.v. administration and exhibits extended circulation lifetimes. Analysis of drug and liposome distribution within the peritoneal cavity of normal mice indicates that as much as 50% of the measured doxorubicin and liposomal lipid is cell-associated. Flow cytometric analysis of the peritoneal cells demonstrated that cell-associated doxorubicin resides almost exclusively within resident peritoneal macrophages. The increased delivery of doxorubicin to the peritoneal cavity of normal mice following i.v. administration of small (0.1-m) liposomal doxorubicin is correlated with a pronounced (>90%) and prolonged (>14-day) suppression of resident peritoneal cells. Liposomal drug accumulation increased dramatically in animals with an established L1210 ascitic tumor. More than 5% of the injected dose was found in the peritoneal cavity of these animals 24 h after treatment with DSPC/chol liposomal doxorubicin as compared with a value of 0.03% of the injected dose achieved with free drug. It is proposed that accumulation of liposomes into the peritoneal cavity of normal and tumor-bearing mice may serve as a useful model for characterizing factors mediating the transfer of liposomes from the vascular compartment to extravascular sites.  相似文献   
74.
The current role of argon laser trabeculoplasty in the treatment of open angle glaucoma is still open discussion. To evaluate the effectiveness of ALT we performed a study on 36 patients followed for 2 years. We noted a success rate of 61.11% after 2 years and noticed that the success rate decreased in time. ALT should be considered as an intermediate therapy in the management of open angle glaucoma, after drug therapy has failed and before filtering surgery is performed.  相似文献   
75.
Twenty-six patients with advanced head and neck cancer, 22 of whom had failed prior surgery and/or radiotherapy, were treated with a combination regimen of cis-diamminedichloroplatinum II, bleomycin, and methotrexate. There were no complete responses. Nine patients achieved a partial response (35%). Three of the four (75%) patients without prior therapy achieved a partial response while only 6 of the 22 patients (27%) with prior surgery and/or radiation therapy obtained a partial response. The median response duration was 3 months. Patients with a partial response did not live significantly longer than those who did not live significantly longer than those who did not respond. Toxic reactions were frequent: there were three episodes of sepsis secondary to leukopenia and two cases of bleomycin pulmonary toxicity. Mucositis was noted in 40% and nausea and vomiting in 60% of patients. We conclude that this triple-drug regimen has little value in the treatment of patients with advanced squamous cell carcinoma of the head and neck who have failed prior surgery and radiotherapy.  相似文献   
76.
This study was designed to determine which objective acoustic or aerodynamic parameters allowed a homogeneous group of patients with unilateral vocal fold paralysis (UVFP) to be distinguished from an age-matched and smoking-matched control group and to search for linear correlations between the objective parameters and the subjective breathiness ratings. Eight patients with recent-onset UVFP and 12 controls were prospectively studied. The acoustic parameters measured for the vowel /a/ at a comfortable frequency and intensity were: jitter, shimmer, harmonics-to-noise ratio, cepstral peak prominence, the difference between the levels of the first two harmonics and the relative energy above 6 kHz. Aerodynamic parameters included the mean flow rate during a sustained /a/ and intraoral pressure during the production of the phoneme /pi/. The long-term average spectrum was calculated for 40 s of text, and the relative average energies in four frequency bands were compared. Six judges rated a mid-/a/ sample using a five-parameter scale with four levels of severity. Nonparametric statistical analysis revealed significant differences ( P<.05) between the UVFP group and the control group for 14 of the 19 parameters studied. Correlations between the objective parameters and perceived breathiness differed in the two groups. Correlations were not always as expected as based on previous literature reports. These measurements provided an objective qualification of voice in patients with UVFP and successfully distinguished them from the normal controls. The objective acoustic and aerodynamic measurements had generally low linear correlations with breathiness ratings in the control group. Higher correlations were seen in the UVFP group, in which breathiness was best correlated with airflow measurements.  相似文献   
77.
Use of radiolabeled antibodies in the treatment of childhood acute leukemia   总被引:1,自引:0,他引:1  
Abstract: Despite advances in therapy for acute leukemia, relapse continues to be the major cause of treatment failure. Hematopoietic stem cell transplant can rescue some patients after relapse, but the ability to escalate the intensity of preparative regimens is limited by toxicity to normal organs. Radiolabeled monoclonal antibodies against hematopoietic antigens have emerged as an alternative to deliver targeted supplemental radiation to sites of leukemic involvement while relatively sparing normal organs. This paper will review the rationale for using this approach, our current experience with radiolabeled anti-CD45 antibody, and the potential challenges encountered in treating children with radiolabeled antibodies.  相似文献   
78.
目的设计并合成与环佐辛有类似的阿片受体亲和活性、在体内具有较长作用时间的3-四氢呋喃甲基苯并吗吩烷类似物。方法8-三氟甲磺酸酯-3-四氢呋喃甲基苯并吗吩烷经催化氨化制得目标物,对目标物进行受体亲和力测定。结果8-氨基及8-苯氨基化合物在体外与μ,δ和κ受体的亲和力均较相应的8-羟基化合物低。结论目标化合物的体外受体亲和力相对较低,但此结果尚不能完全说明其在体内的作用情况及其可否用于毒品成瘾的治疗。进一步研究正在进行。  相似文献   
79.
PURPOSE: To assess the antitumor efficacy of pharmacokinetically guided topotecan dosing in previously untreated patients with medulloblastoma and supratentorial primitive neuroectodermal tumors, and to evaluate plasma and CSF disposition of topotecan in these patients. PATIENTS AND METHODS: After maximal surgical resection, 44 children with previously untreated high-risk medulloblastoma were enrolled, of which 36 were assessable for response. The topotecan window consisted of two cycles, administered initially as a 30-minute infusion daily for 5 days, lasting 6 weeks. Pharmacokinetic studies were conducted on day 1 to attain a topotecan lactone area under the plasma concentration-time curve (AUC) of 120 to 160 ng/mL.h. After 10 patients were enrolled, the infusion was modified to 4 hours, with dosage individualization. RESULTS: Of 36 assessable patients, four patients (11.1%) had a complete response and six (16.6%) showed a partial response, and disease was stable in 17 patients (47.2%). Toxicity was mostly hematologic, with only one patient experiencing treatment delay. The target plasma AUC was achieved in 24 of 32 studies (75%) in the 30-minute infusion group, and in 58 of 93 studies (62%) in the 4-hour infusion group. The desired CSF topotecan exposure was achieved in seven of eight pharmacokinetic studies when the topotecan plasma AUC was within target range. CONCLUSION: Topotecan is an effective agent against pediatric medulloblastoma in patients who have received no therapy other than surgery. Pharmacokinetically guided dosing achieved the target plasma AUC in the majority of patients. This drug warrants testing as part of standard postradiation chemotherapeutic regimens. Furthermore, these results emphasize the importance of translational research in drug development, which in this case identified an effective drug.  相似文献   
80.
BACKGROUND: We used a murine model of orthotopic corneal transplantation to determine whether host deficiency in ICAM-1 promotes survival of corneal grafts with different degrees of allodisparity. METHODS: ICAM-1-/- and wild-type C57BL/6 (ICAM-1+/+) received corneal grafts from the following strains of mice: BALB/c (fully mismatched), BALB.b (mismatched at multiple minor H only), or B10.D2 [including major histocompatibility complex (MHC) mismatch]. Graft rejection, induction of allospecific delayed-type hypersensitivity (DTH) responses, and leukocytic infiltration of grafts were measured. RESULTS: There were no differences in long-term survival of allografts that were either fully mismatched or had only minor H disparity in ICAM-1+/+ vs. ICAM-1-/-hosts. However, whereas B10.D2 grafts were accepted in only 58% of the ICAM-1+/+ hosts, graft survival in ICAM-1-/- recipients was 100% (P=0.006). Moreover, none of the ICAM-1-/- mice receiving B10.D2 grafts developed allospecific DTH. CONCLUSIONS: Prolonged survival seen in MHC-mismatched grafts in ICAM-1-/- mice, along with a suppressed DTH response to donor alloantigens after transplantation, suggest that ICAM-1 is associated with recipient sensitization to MHC alloantigens.  相似文献   
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