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61.
International Journal of Mental Health and Addiction - The use of synthetic cannabinoids (SCs) has been steadily increasing in recent years and represents a new class of substances of abuse....  相似文献   
62.
This paper proposes that anorexia nervosa patients are a psychodynamically heterogeneous group and can be usefully divided into three subtypes — the borderline; the empty, understructured; and the emotionally-conflicted, identity-confused. Clinical experience and the long-term outcome literature challenge any uniformity assumptions about anorexia nervosa. It is noted that anorexia nervosa appears to be a “spectrum disorder” with presentations ranging from normative adolescent concern about weight, dieting, appearance, etc. to severe psychopathology and classical anorexic symptomatology among those predisposed.  相似文献   
63.
Spirogermanium is a metal-containing compound reported to have antitumor, antiarthritic, antimalarial and immunoregulatory activity. In this study we have demonstrated that spirogermanium inhibited antibody synthesis to sheep red blood cells in BDF1 mice in vivo. Spleen cells from these treated mice were unable to respond to this antigen in vitro, and suppressed both the antibody response of normal cells to SRBC and the mitogenic response of normal cells to Concanavalin A in co-culture assays. The cells responsible for this suppression did not belong to the T cell lineage since treatment with anti-Thy-1.2 antiserum and complement did not abrogate the suppression. The suppressor cells were found to be radiation resistant and nylon wool adherent. Plastic adherence or passage over Sephadex G10 partially removed the suppression indicating the contribution, at least in part, of a suppressor macrophage. The plastic non-adherent population of cells also contained suppressor cells which were detected following anti-thy-1.2 treatment and selection by panning on anti-IgG coated plates. Fluorescent antibody and flow cytometry technology showed the population of suppressor cells to be 90% immunoglobulin positive, indicative of a B cell lineage.  相似文献   
64.
目的:观察急性髓性白血病经混合造血干细胞移植后,应用供者淋巴细胞输注 白细胞介素2治疗的效果,并与移植后未经特殊治疗的效果进行比较。方法:①选取2000-01/2004-07解放军兰州军区兰州总医院全军血液病中心收治的19例急性髓性白血病患者,实验经医院伦理委员会批准,患者均知情同意。随机数字表法分为两组:观察组8例,年龄17~40岁,M2a 4例,M4 1例,M5a 3例;对照组11例,年龄19~39岁,M2a 2例,M3a 2例,M4 3例,M5a 4例。②两组患者采用化疗联合重组人粒细胞集落刺激因子的方法动员自体外周血造血干细胞,采集后液氮中保存5d备用。③术前采用直线加速器对患者全身及肺部照射,预处理完毕后实施混合造血干细胞移植。首先回输自体单个核细胞中位数为4×108/kg,CD34 细胞中位数为6.2×106/kg,粒-巨噬祖细胞集落形成单位中位数为5.8×104/kg。间隔1~6h后,采集人类白细胞抗原半相合异体骨髓,按回输自体单个核细胞数的1/6~1/10输注给患者。④两组患者移植期间均住无菌层流病房,给予相应并发症的防治及支持治疗。在粒细胞降至0时注射重组人粒细胞集落刺激因子150μg/12h,促进造血恢复。观察组给予供者淋巴细胞输注 白细胞介素2治疗,每次采集的供者淋巴细胞中,CD3 淋巴细胞中位数为1.43×108/kg,CD4 细胞中位数为0.97×108/kg,CD8 细胞中位数为0.41×108/kg,中位治疗次数4(1~7)次,回输后即开始应用100wu/d重组人白细胞介素2,共10d。对照组混合造血干细胞移植后未给予特殊治疗。结果:19例急性髓性白血病患者均进入结果分析。①造血恢复:两组患者均获得造血重建,术后4~9d粒细胞均降至0,12~17d粒细胞达0.5×109L-1,16~21d白细胞达4.0×108 L-1,19~23 d血小板达20×108 L-1。16~21 d骨髓检查示恢复期骨髓象。②术后并发症:两组患者不同程度地出现口腔溃疡,随着造血恢复,7~10d溃疡消失。观察组1例患者出现出血性膀胱炎,两组各2例患者出现发热。无肝静脉闭塞病和移植物抗宿主病发生。③嵌合体形成:观察组中1例M4患者形成嵌合体,对照组中2例M4患者与1例M5患者形成嵌合体,嵌合体持续存在3~12个月。④供者淋巴细胞输注 白细胞介素2疗效:观察组中有1例M2a患者在接受2次特殊治疗后7个月复发死亡;1例M2a患者接受2次特殊治疗后1年出现骨髓增生异常综合征,脑出血死亡,1例M5a患者应用特殊治疗1次后出现不明原因高热、抽搐,死于癫痫持续状态,其余5例患者随访2年均健康存活,长期生存率为62.5%(5/8)。对照组有2例M2a患者、2例M4患者、1例M5患者于移植后1~7个月复发死亡,1例M3患者于移植后25d死于脑出血,其余2例M3患者、2例M4患者、1例M5患者随访2年均健康存活,长期生存率为45.4%(5/11)。结论:混合造血干细胞移植后应用供者淋巴细胞输注 白细胞介素2治疗,急性髓性白血病患者均获得造血重建且无移植物抗宿主病发生,其长期生存率有效提高。  相似文献   
65.
66.
Background:  Trazodone is a commonly prescribed off-label for sleep disturbance in alcohol-dependent patients, but its safety and efficacy for this indication is unknown.
Methods:  We conducted a randomized, double-blind, placebo-control trial of low-dose trazodone (50 to 150 mg at bedtime) for 12 weeks among 173 alcohol detoxification patients who reported current sleep disturbance on a validated measure of sleep quality or during prior periods of abstinence. Primary outcomes were the proportion of days abstinent and drinks per drinking day over 6-months; sleep quality was also assessed.
Results:  Urn randomization balanced baseline features among the 88 subjects who received trazodone and 85 who received placebo. The trazodone group experienced less improvement in the proportion of days abstinent during administration of study medication (mean change between baseline and 3 months: −0.12; 95% CI: −0.15 to −0.09), and an increase in the number of drinks per drinking day on cessation of the study medication (mean change between baseline and 6 months, 4.6; 95% CI: 2.1 to 7.1). Trazodone was associated with improved sleep quality during its administration (mean change on the Pittsburgh Sleep Quality Index between baseline and 3 months: −3.02; 95% CI: −3.38 to −2.67), but after it was stopped sleep quality equalized with placebo.
Conclusions:  Trazodone, despite a short-term benefit on sleep quality, might impede improvements in alcohol consumption in the postdetoxification period and lead to increased drinking when stopped. Until further studies have established benefits and safety, routine initiation of trazodone for sleep disturbance cannot be recommended with confidence during the period after detoxification from alcoholism.  相似文献   
67.
68.
Cardiomyocyte contraction and relaxation are controlled by Ca(2+) handling, which can be regulated to meet demand. Indeed, major reduction in sarcoplasmic reticulum (SR) function in mice with Serca2 knockout (KO) is compensated by enhanced plasmalemmal Ca(2+) fluxes. Here we investigate whether altered Ca(2+) fluxes are facilitated by reorganization of cardiomyocyte ultrastructure. Hearts were fixed for electron microscopy and enzymatically dissociated for confocal microscopy and electrophysiology. SR relative surface area and volume densities were reduced by 63% and 76%, indicating marked loss and collapse of the free SR in KO. Although overall cardiomyocyte dimensions were unaltered, total surface area was increased. This resulted from increased T-tubule density, as revealed by confocal images. Fourier analysis indicated a maintained organization of transverse T-tubules but an increased presence of longitudinal T-tubules. This demonstrates a remarkable plasticity of the tubular system in the adult myocardium. Immunocytochemical data showed that the newly grown longitudinal T-tubules contained Na(+)/Ca(2+)-exchanger proximal to ryanodine receptors in the SR but did not contain Ca(2+)-channels. Ca(2+) measurements demonstrated a switch from SR-driven to Ca(2+) influx-driven Ca(2+) transients in KO. Still, SR Ca(2+) release constituted 20% of the Ca(2+) transient in KO. Mathematical modeling suggested that Ca(2+) influx via Na(+)/Ca(2+)-exchange in longitudinal T-tubules triggers release from apposing ryanodine receptors in KO, partially compensating for reduced SERCA by allowing for local Ca(2+) release near the myofilaments. T-tubule proliferation occurs without loss of the original ordered transverse orientation and thus constitutes the basis for compensation of the declining SR function without structural disarrangement.  相似文献   
69.
A randomized trial of nicotine enemas for active ulcerative colitis.   总被引:1,自引:0,他引:1  
BACKGROUND & AIMS: Ulcerative colitis (UC) is largely a disease of nonsmokers in which transdermal nicotine improves the symptoms but often causes adverse events (AEs). Nicotine enemas cause fewer AEs and were used as supplemental treatment for active UC. METHODS: We treated 104 patients with active UC with either 6-mg nicotine enemas or placebo enemas for 6 weeks in a randomized double-blind study. Patients continued their oral therapy, if any, for UC: 68 patients were taking mesalamine, 15 patients were taking prednisolone, and 12 patients were taking thiopurines during the study. Clinical, sigmoidoscopic, and histologic assessments were made at baseline and at the end of the study and symptoms were recorded daily on a diary card. The primary end point was induction of clinical remission and clinical improvement also was measured by the UC disease activity index. After the study, patients then used nicotine enemas daily for 4 weeks and sigmoidoscopy with a biopsy examination was repeated. AEs and salivary cotinine levels were monitored throughout the study. RESULTS: Clinical remission was achieved in 14 of 52 (27%) patients on active treatment and 14 of 43 (33%) patients on placebo (P = .55). The UC disease activity index improved by 1.45 points in the active group and by 1.65 points for those on placebo (P = .88). Only 1 patient discontinued treatment because of an AE (abdominal pain). In the 47 patients taking mesalamine only, active treatment conferred benefit that was not statistically significant; disease remission occurred in 9 of 25 patients on active therapy and 4 of 21 patients on placebo (P = .20). CONCLUSIONS: Six-milligram nicotine enemas were well tolerated but were not found to be efficacious for active UC.  相似文献   
70.
Cancer predisposition of ataxia-telangiectasia heterozygotes   总被引:2,自引:0,他引:2  
Ataxia-telangiectasia (A-T) is a progressive neurologic disorder in which there is varied immune dysfunction, an excess sensitivity to ionizing radiation, and a striking predisposition to cancer. It is the autosomal recessive syndrome for which there is the strongest evidence, derived from retrospective studies of cancer incidence and mortality in A-T families, that the heterozygote is predisposed to cancer. We present, in tabular form, the specific cancer sites or types most likely to be associated with A-T heterozygosity. These include solid tumors of the breast, pancreas, stomach, bladder, and ovary, and chronic lymphocytic leukemia. We also introduce a new method to test these associations. As soon as molecular probes for the A-T allele(s) are available, this new research design will be used to test rigorously each association, hypothesized on the basis of previous data, between a specific cancer site and A-T heterozygosity.  相似文献   
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