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121.
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Alexander P 《AIDS health promotion exchange / World Health Organization, Global Programme on AIDS, Health Promotion Unit》1992,(1):4-6
In the last 20 years prostitutes, or sex workers, have formed self-help and advocacy organizations in a number of countries that could have an effect on acquired immunodeficiency syndrome (AIDS) and sexually transmitted disease (STD) prevention efforts. It is essential when planning a sex work-related intervention to identify sex workers, clients, or third parties as well as any factors that affect the safety of existing sex and drug use practices. It is important to know where sex workers and clients contact each other, where they go to engage in sex, and the working conditions of sex work establishments. Other considerations include the accessibility of condoms and health care; the impact of laws, regulations, and enforcement practices; and the impact of migration of both sex workers and clients. Many projects have involved members of the target audiences in the assessment as interviewers as well as in the design and implementation of the project. All interventions should include current information, education, and communication consisting of media strategies as well as person-to-person strategies. A combination of sites can help to reach the maximum proportion of the population at risk. Several projects have provided bulk supplies in order to ensure access to condoms at no cost or inexpensively to hotels, bars, brothels and other sex work businesses. Projects have also promoted the use of sterile injection equipment where injecting drug use is common. Functioning outreach and education projects emphasize STD service, such as sensitivity training for health care providers to improve services and diagnostic procedures and to motivate sex workers to utilize the health care system. Voluntary utilization may the boosted by offering STD services in a stationary or mobile clinic in the sex work neighborhoods during the afternoon and early evening and combining them with family planning, primary health care, and child health care. 相似文献
123.
A reassessment of the role of arteriography in penetrating proximity extremity trauma: a prospective study 总被引:4,自引:0,他引:4
E R Frykberg J M Crump F S Vines G L McLellan J W Dennis R G Brunner R H Alexander 《The Journal of trauma》1989,29(8):1041-50; discussion 1050-2
Penetrating proximity extremity trauma (PPET) was prospectively studied to clarify the role of routine arteriographic evaluation (AG). Over a 24-month period, 135 patients were identified with 152 injuries from PPET. All patients underwent AG and were randomized to either immediate or delayed timing. There were 27 arteriographic abnormalities from these 152 wounds, of which 16 (10.5%) were in major arteries. One acute arteriovenous fistula underwent immediate surgery. The remaining 15 major vessel injuries were nonoperatively observed, including seven cases of segmental arterial narrowing, six intimal flaps, and two small pseudoaneurysms (one of which enlarged and underwent surgical repair after 10 weeks of followup). Nine of the remaining 14 lesions resolved; two improved and three remained clinically unchanged over a mean followup interval of 2.7 months. Shotgun trauma was the mechanism which carried the greatest risk of significant vascular injury. Although "soft" clinical signs were significantly more predictive of vascular injury following PPET than proximity alone (p less than 0.0005), 50% of all injuries to major arteries did not manifest soft signs. No extremity morbidity resulted from delayed AG or from vascular injury management. We conclude from our study population: 1) the natural history of clinically occult arterial injuries was predominantly benign; 2) AG could be safely delayed up to 24 hours; 3) "soft" signs were not clinically useful predictors of vascular injury; and 4) with the exception of shotgun wounds, AG did not appear to be a cost effective screening modality, since detection of a single vascular injury requiring surgery cost $66,420.00. 相似文献
124.
Localization of SNARE proteins and secretory organelle proteins in astrocytes in vitro and in situ 总被引:1,自引:0,他引:1
Wilhelm A Volknandt W Langer D Nolte C Kettenmann H Zimmermann H 《Neuroscience research》2004,48(3):249-257
Astrocytes are capable of regulated release of messenger molecules. Astrocytes cultured from new born rodent brain express a variety of classical presynaptic proteins. We investigated the question whether the capability to express synaptic proteins in culture was a feature only of immature astrocytes, and whether these proteins were also expressed by astrocytes in situ. Experiments were performed with transgenic mice expressing the enhanced green fluorescent protein under the control of the human glial fibrillary acidic protein promoter. Using double fluorescence and astrocytes cultured from 1 to 16 day-old animals we show that the astrocytic expression of synaptic proteins in culture is invariant of the age of donor animals. Culturing can induce the astrocytic expression of specific synaptic proteins such as SV2, synaptophysin and SNAP-25. Astrocytes in brain sections of 1-16 day-old animals revealed a punctuate immunofluorescence for secretory carrier membrane protein (SCAMP), SNAP-23, synaptobrevin II, and cellubrevin, to a minor extent for SNAP-25 and synaptophysin, and none for SV2. Our results demonstrate that cultured astrocytes express synaptic proteins not present in situ. Nevertheless, astrocytic organelles in situ are equipped with molecules that could be involved in regulated exocytosis of messenger substances. 相似文献
125.
An electron microscopical study has been carried out to evaluate the effect of neonatal thymectomy on the hypophysis of germ-free mice at different times after the operation. The results fully confirm the previous findings in neonatally thymectomized, conventional mice. Also neonatal thymectomy in germ-free mice results in degranulation of growth hormone-producing cells in the anterior pituitary gland. A large number of these cells show an enlarged endoplasmic reticulum with formation of cisternae and loss of hormone granuli. This alteration of growth hormone-producing cells is similar to that observed in other cells of the hypophysis after removal of other target glands such as thyroid or gonads. The changes in the growth hormone-producing cells in neonatally thymectomized germ-free mice occur even in the first days after birth, when the number of differentiated growth hormone-producing cells is still very low.
Some thymectomized germ-free mice showed symptoms of the wasting syndrome but the alterations in their hypophysis were not more pronounced than those observed in thymectomized germ-free but nonwasting mice. The data fit well our suggestion that the perinatal thymus is under hypophysial control and that immunological maturation depends on endocrine function.
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129.
Timo L. M. ten Hagen Ann L. B. Seynhaeve Alexander M. M. Eggermont 《Immunological reviews》2008,222(1):299-315
Summary: Solid tumor therapy with chemotherapeutics greatly depends on the efficiency with which drugs are delivered to tumor cells. The typical characteristics of the tumor physiology promote but also appose accumulation of blood-borne agents. The leaky tumor vasculature allows easy passage of drugs. However, the disorganized vasculature causes heterogeneous blood flow, and together with the often-elevated interstitial fluid pressure, this state results in poor intratumoral drug levels and failure of treatment. Manipulation of the tumor vasculature could overcome these barriers and promote drug delivery. Targeting the vasculature has several advantages. The endothelial lining is readily accessible and the first to be encountered after systemic injection. Second, endothelial cells tend to be more stable than tumor cells and thus less likely to develop resistance to therapy. Third, targeting the tumor vasculature can have dual effects: (i) manipulation of the vasculature can enhance concomitant chemotherapy, and (ii) subsequent destruction of the vasculature can help to kill the tumor. In particular, tumor necrosis factor α is studied. Its action on solid tumors, both directly through tumor cell killing and destruction of the tumor vasculature and indirectly through manipulation of the tumor physiology, is complex. Understanding the mechanism of TNF and agents with comparable action on solid tumors is an important focus to further develop combination immunotherapy strategies. 相似文献
130.
STUDY OBJECTIVES: To correlate memory measures with a trait measure of chronic daytime somnolence in cognitively normal individuals with different gene doses of the apolipoprotein E (APOE) e4 allele, a common Alzheimer's disease susceptibility gene. DESIGN: Cross-sectional, exploratory study of cognitive abilities in APOE e4 homozygotes (HMZ) (n=42), heterozygotes (HTZ), (n=42) and noncarriers (NC) (n=42) who are matched for age, gender, educational level, and family history of dementia. SETTING: Tertiary care academic medical center. PARTICIPANTS: Cognitively normal residents of Maricopa County, Arizona who are 30-70 years of age, genotyped for APOE, and have no history of a sleep disorder INTERVENTIONS: N/A. MEASUREMENTS: Epworth Sleepiness Scale (ESS) and a battery of neuropsychological tests RESULTS: Age, education, gender, and insomnia complaints did not significantly differ among groups. Despite normal baseline memory scores, memory declined with increasing ESS on all eight memory measures in the HMZ, two of eight in the HTZ, and one of eight in the NC. Differences between HMZ and NC on the slope of memory decline with increasing ESS reached statistical significance on two verbal memory measures, AVLT Long-Term Memory (p=0.048) and Percent Delayed Recall (p=0.035). CONCLUSIONS: Chronic daytime somnolence is associated with a distinctive decline in verbal memory in cognitively normal APOE e4 HMZ, a group at particularly high risk of Alzheimer's disease. Additional studies are needed to confirm these exploratory findings and to determine the effects of acute somnolence on cognition in these genetic subgroups. 相似文献