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91.
1993年3月对已建立一年的吸毒者定群研究现场──云南省德宏州瑞丽市、陇川县及潞西县再次进行调查。本次调查755例吸毒者及102例配偶。从1992年进入定群研究HIV阴性的89例静脉吸毒者中,1993年又采到血样有54例,其中9例血清转阳。瑞丽市、陇川县及潞西县1992年和1993年静注者血清阳转率(/百观察人年)分别为43.2%及40.0%,12.2%及12.2%,0%及0%。1993年新进入定群研究的116例静注者中,采集到血样的有104例,发现HIV阳性38例。上述三市县1992年及1993年入定群研究的静注者的HIV感染率分别为81.8%及85.7%,44.6%及40.0%,5.1%及0%。可以看出血清阳转率的高低与HIV感染率高低相吻合。HIV阳性者的配偶1990、1992及1993年的HIV感染率分别为3.1%、9.8%和7.4%,有上升趋势。潞西县HIV阳性者少,静脉注射出现时间晚,但近年来静脉吸毒者比例上升快,值得注意。 相似文献
92.
Delineating the sites and progression of in vivo atrophy in multiple system atrophy using fluid-registered MRI. 总被引:1,自引:0,他引:1
Jonathan M Schott Jessica E Simon Nick C Fox Andrew P King M Nadeem Khan Lisa Cipolotti Dominic C Paviour John M Stevens Martin N Rossor 《Movement disorders》2003,18(8):955-958
We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA. 相似文献
93.
维胺酯-β-环糊精包合物的研究 总被引:6,自引:0,他引:6
应用3因素8水平的均匀设计方法,优化出维胺酯-β-环糊精包合物最佳制备条件,所得包合物的包合率为99.3%,其表观稳定常数为1394M-1. 相似文献
94.
C. Pozzilli V. Tomassini F. Marinelli A. Paolillo C. Gasperini S. Bastianello 《European journal of neurology》2003,10(1):95-97
The authors evaluated the gender difference in the magnetic resonance imaging characteristics of the lesions occurring in the brain of 413 multiple sclerosis (MS) patients. Men had fewer contrast-enhancing lesions (P = 0.01), but a higher proportion of lesions evolving into 'black holes' (P = 0.001), when compared with women. Thus, our data indicate that men with MS are prone to develop less inflammatory, but more destructive lesions than women. This study results provides support for a modulation of the MS pathological changes by gender. 相似文献
95.
It is shown that a repetitive pulse sequence consisting of two 90° pulses and gradients in a 1:2 ratio around the second 90° pulse generates interscan shifted stimulated echoes (SSTEs) and intrascan multiple spin echoes (MSEs). Separation of these two types of signals is accomplished using specific gradient crusher schemes. The intensity of the SSTEs is an order of magnitude larger than that of the MSEs and determines the signal contrast if both effects are selected simultaneously. The SSTE sequence generates improved contrast between gray and white matter, even at high field, which is explained in terms of increased inverse T1-weighting for the interscan echo. The MSE image has low signal to noise and no detectable contrast. The effect of interscan diffusion weighting is also discussed. 相似文献
96.
Cohen syndrome: fertility in a female patient 总被引:1,自引:0,他引:1
In this report we describe fertility in an adult female with Cohen syndrome. She gave birth to a son, now 1.5 years old, with discrete facial stigmata and slight psychomotor retardation. 相似文献
97.
Claudia Giaroli Gianfranco Riccò Gianni Vecchi Stefano Belli Caterina Bruno Mario Grignoli Silvia Candela Salvatore Minisci Roberto Poletti Guiseppina Venturi Antonio Ziccardi Pietro Comba 《International archives of occupational and environmental health》1994,66(1):7-11
The present study describes cause-specific mortality of asbestos cement workers in the Emilia Romagna region of Italy. The cohort included workers in ten factories, most of which started operating between 1955 and 1965. Asbestos, mainly chrysotile, constituted 10%–20% of the dry component of the mixture. Crocidolite range between 5% and 50% of total asbestos. Asbestos concentrations up to 44 ff/cc were reported prior to 1975, while in recent years they have usually been below 0–1 ff/cc. The cohort included 3341 workers who had at some time been employed in the ten factories under study. Their mortality experience was compared with that of the population resident in Emilia Romagna. Vital status was ascertained at 1989. Seventy-three subjects were lost to followup (2.2%). Mortality from all causes and from all types of cancer was increased in the cohort. Malignant neoplasms of the respiratory tract showed a significant increase (SMR: 134; 90% confidence interval: 101–175; 40 observed) due to lung cancer (SMR: 124; 90% confidence interval: 91–166; 33 observed) and neoplasms of the pleura, mediastinum, and other parts of the respiratory tract (SMR: 602; 90% confidence interval 237–1267; 5 observed). The discrepancy between observed and expected mortality mainly concerned subjects with at least 20 years of employment in the factories. Five more cases of histologically confirmed mesothelioma occurred after the end of follow-up. 相似文献
98.
目的观察耐药乳腺癌细胞c-myc表达及其反义寡核苷酸对耐药的逆转效应,探讨c-myc在耐药调控中的作用。方法运用流式细胞仪检测乳腺癌耐药细胞MCF-7/Adr和其药敏亲本系MCF-7的c-myc表达水平。MTT法测定阿霉素作用于上述细胞的药物半数抑制浓度(IC50)。结果MCF-7/Adr耐药细胞c-myc的表达率为70.48%,其亲本药敏细胞系MCF-7c-myc表达率仅46.02%,前者显著高于后者(P<0.05)。阿霉素单独作用于MCF-7/Adr,IC50值为(22.00±1.92)μmol/L,但与4μmol/Lc-myc反义寡核苷酸共孵育后,阿霉素的IC50值则显著下降为(9.60±1.04)μmol/L。结论与其亲本药敏细胞相比较,MCF-7/Adr的c-myc表达显著上调,抑制c-myc的过表达可部分逆转MCF-7/Adr的阿霉素抵抗,提示c-myc参与肿瘤耐药的发生。 相似文献
99.
Data from studies of rankings of acceptability and severity of various disabilities were converted to a common metric of percentile equivalent ranks. A total of 1331 data points from 53 studies yielded the following overall percentile equivalent ranks for 24 disabilities: diabetes (most acceptable), ulcer, arthritis, asthma, heart condition, speech problems, crippled, orthopedic disability, physical disability, amputation, emotional disturbance, appearance disability, deafness, learning disability, stroke, cancer, paraplegia, blindness, epilepsy, tuberculosis, cerebral palsy, mental retardation, mental illness, and multiple disabilities (least acceptable). Rankings of the severity of seven disabilities yielded a somewhat different order that correlated 0.55 with the total data. Rankings of a mild disability were, on average, 40 percentile points higher than rankings for the same disability labeled severe or profound. 相似文献
100.
Kirk J. Schneider 《Clinical psychology》2002,9(1):26-27
I contend that although the Luborsky et al. findings on the Dodo bird verdict are noteworthy, the methodology on which they are based is significantly delimited. Amplifying Luborsky et al.'s moderate recognition of that delimitation, I propose a qualitative complement to the extant research. I call this complement "amalgamated" qualitative research and propose that it will deepen, clarify, and contextualize Luborsky et al.'s enigmatic findings. Until this amalgam is implemented, therapy research will be relegated to impressions rather than fine-grained illuminations. 相似文献