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71.
The purpose of this research was to study the epidemiology of psychotropic drug use among the general population and to draw comparisons to drug use among clients of medical, mental health, and social services in the same jurisdiction. Results showed considerably higher percentages of users for all drug categories among agency clientele. Age and sex differences in drug use replicated previous research in the general population but were noticeably absent among the clients of local services. Notably, the proportion of long-term daily users of minor tranquilizers in the agency population was about three times that of the general population. However, tranquilizer users in the two populations were similar in many respects. Results of the study are discussed in terms of the need for screening for persons with psychotropic drug problems in health and social services.  相似文献   
72.
OBJECTIVES: The prevalence of problem and gambling behavior, the average age of onset of gambling behavior, and the co-occurrence of gambling disorder with substance use were determined in the Louisiana student population grades 6 through 12. METHODS: A stratified randomized sample of 12,066 students in Louisiana schools during the 1996-1997 school year was surveyed about gambling behavior using the South Oaks Gambling Screen--Revised for Adolescents (SOGS-RA). RESULTS: Fourteen percent of the students never gambled, 70.1 percent gambled without problems, 10.1 percent indicated problem gambling in the past year (level 2 according to the SOGS-RA), and 5.8 percent indicated pathological gambling behavior in the past year (level 3). Weekly or more frequent lottery play was reported by 16.5 percent. The average age of onset of gambling behavior was 11.2 years. Fifty-nine percent of the students with problem and pathological gambling behavior reported frequent alcohol and illicit drug use. CONCLUSIONS: A significant minority of Louisiana students in grades 6 through 12-15.9 percent--acknowledged gambling-related symptoms and life problems. The association of problem and pathological gambling with use of alcohol, tobacco, and marijuana provides preliminary support for the inclusion of gambling among other adolescent risk behaviors.  相似文献   
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Lipids that are found only in the cell envelope of pathogenic mycobacteria, such as those containing multiple methyl-branched fatty acids, have long been thought to play a role in pathogenesis. Among these complex lipids, sulfolipids have been the most extensively studied over the last 50 years. The numerous biological effects exhibited by purified sulfolipids on phagocytic cells led to the idea that these molecules are probably important virulence factors facilitating the intracellular survival of Mycobacterium tuberculosis. However, definitive evidence to support this concept has been lacking. The recent construction of an isogenic sulfolipid-deficient mutant of M. tuberculosis H37Rv (Sirakova et al., J. Biol. Chem. 276:16833-16839, 2001) has for the first time provided the opportunity to directly assess the contribution of these complex lipids to pathogenesis. In the present study, we show that against all expectations, sulfolipid deficiency does not significantly affect the replication, persistence, and pathogenicity of M. tuberculosis H37Rv in mice and guinea pigs or in cultured macrophages.  相似文献   
76.
Not only does breast milk provides an ideal nutrient composition for the newborn, but it also contains a variety of substances that may actively influence growth and development of the infant and stimulate neonatal protection against gastrointestinal diseases. Hormones, growth factors, cytokines and even whole cells are present in breast milk and act to establish biochemical and immunological communication between mother and child. In addition, milk nutrients such as nucleotides, glutamine and lactoferrin have been shown to influence gastrointestinal development and host defense. The unique properties of milk as a mediator of biochemical messages will be presented and the clinical significance of breastfeeding in the prevention of neonatal gastrointestinal diseases will be discussed.  相似文献   
77.
Previously we have described the properties of store-operated channel currents (SOCs) in freshly dispersed rabbit portal vein smooth muscle cells. In addition to Ca2+ store depletion these SOCs could also be activated by α-adrenoceptor stimulation and diacylglycerol (DAG) via a protein kinase C (PKC)-dependent mechanism. In the present study we have investigated the effect of β-adrenoceptor stimulation on SOCs in rabbit portal vein myocytes. With whole-cell recording the selective β-adrenoceptor agonist isoprenaline reduced the current evoked by cyclopiazonic acid (CPA, sarcoplasmic/endoplasmic reticulum ATPase inhibitor) by over 85%. With cell-attached patch recording, bath application of isoprenaline produced a pronounced inhibition of SOC activity evoked by either CPA or the acetoxymethyl ester form of BAPTA (BAPTA-AM). SOC activity evoked by CPA, the DAG analogue, 1-oleoyl-acetyl- sn -glycerol (OAG) or the phorbol ester, phorbol-12,13-dibutyrate (PDBu) was also markedly inhibited by the adenylate cyclase activator, forskolin, and the cell-permeable non-hydrolysable analogue of cyclic adenosine monophosphate (cAMP), 8-Br-cAMP. With inside-out patches, bath application of PDBu evoked channel currents with similar properties to SOCs which were inhibited by over 90% by a catalytic subunit of protein kinase A (PKA) and by 8-Br-cAMP. Moreover bath application of PKA inhibitors, H-89, KT5720 and an inhibitory peptide to quiescent cell-attached or inside-out patches, activated channel currents with similar properties to SOCs. These data suggest that in rabbit portal vein myocytes, stimulation of β-adrenoceptors inhibits SOC activity via a cAMP-dependent protein kinase signal transduction cascade. In addition it is concluded that constitutive PKA activity has a profound inhibitory effect on SOC activity in this vascular preparation.  相似文献   
78.
目的:研究低氧时小鼠肺组织中低氧诱导因子-1α(HIF-k)表达的变化。方法:实验用雄性小鼠,低氧仓浓度分别为10%、7%、5%。用免疫荧光组织化学技术及共聚焦显微术,检测小鼠在低氧条件下肺组织中HIF-1α表达的变化。结果:正常组小鼠肺组织HIF-1α无表达,低氧组HIF-1α表达增加,且随低氧时间的延长及低氧强度的增加而增强。结论:低氧可诱导小鼠肺组织中HIF-1α的表达增强,(HIF-k)可能参与肺组织细胞凋亡的发生。  相似文献   
79.
The aim of this study is to investigate whether three mononucleotide polymorphisms at the locus -1082,-819 and -592 in the promoter region of the IL-10 gene are associated with chronic severe hepatitis. The IL-10-592 and IL-10-1082 polymorphisms were genotyped by polymerase chain reactionrestriction fragment length polymorphism analysis (PCR-RFLP) while polymerase chain reaction-sequence specific primer (PCR-SSP) assay was used to test the IL-10-819 polymorphism. The polymorphisms of IL-10-1082, -819 and -592 genes were detected in 98 patients with chronic severe hepatitis (CSH), 478 patients with chronic hepatitis B (CHB), 223 asymptomatic (chronic) HBV carriers (ASC) and 267 patients with self-restricted HBV. There was significant difference of the polymorphisms of IL-10-1082, IL-10-819 and IL-10-592 genes between CSH group and other groups. The frequency of AA genotype at IL-10 gene promoter -1082 locus in chronic severe hepatitis patients was higher than that in asymptomatic HBV carriers (2 = 13. 314, P = 0.001), and self-restricted HBV patients (χ^2 = 13.545, P = 0.000); the frequency of CC and AC genotype at IL-10 gene promoter -592 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 15.970, P=0.000) (χ^2 =20.414, P=0.000), asymptomatic HBV carriers (χ^2 =21.283, P= 0.000) (χ^2 = 28.309, P = 0.000) and self-restricted HBV patients(χ^2 = 17.047, P = 0.000) (χ^2 = 16.528, P = 0.000) ; the frequency of TC genotype at IL-10 gene promoter -819 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 58.961, P = 0.000), asymptomatic HBV carriers ( χ^2 = 53. 255, P = 0. 001 ) and self-restricted HBV patients (χ^2 = 39.616, P = 0.001). So interleukine-10 gene polymorphism was associated with the chronic severe hepatitis.  相似文献   
80.
目的为斜坡区肿瘤手术提供解剖资料。方法20例整颅,10例行水平切面,10例行正中矢状切面。测量切牙孔、前鼻棘、后鼻棘、枕骨大孔前端、枕髁前端、卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至咽结节的距离;测量卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至正中线的距离;测量枕骨基底部颅底外面的长径、枕骨大孔纵径(FML)、枕骨大孔前正中点与枕髁后缘连线垂直距离(AOCP)、枕髁轴径(OCA)、枕髁间距。结果切牙孔后缘、前鼻棘、后鼻棘、枕骨大孔前端、枕髁前端、卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至咽结节的距离分别为(mm):72.12±4.25、77.77±3.89、33.73±2.07、13.14±1.91、15.71±1.74、27.51±2.12、15.98±1.98、25.93±2.23、19.15±1.49。卵圆孔、破裂孔、颈动脉管及舌下神经管外口的内侧缘至中线的距离分别为:25.55±1.63、11.72±1.70、25.75±1.98、17.41±1.41。枕骨基底部颅底外面长径、FML、AOCP、OCA、枕髁间距分别为(mm):28.80±2.67、35.84±2.59、17.10±1.13、24.55±2.35、21.07±1.92。结论经口咽至斜坡区的手术入路中,开骨窗时安全范围是以咽结节为中心,以15mm为半径做斜坡磨除;也可以做矩形骨窗,即以咽结节为中心开一长(高)25mm×宽20mm的骨窗。  相似文献   
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