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1.
In this paper, the authors describe some of the complexities of collecting and presenting data on race and ethnicity based on the experiences of the Bureau of the Census. Different methods of data collection, different content and format of questions, and different definitions make it difficult to collect consistent race and ethnic data across data systems. The Bureau of the Census experiences have shown that changing ethnic self-identity and concepts, intent of the question, consistency of reporting, and the classification of persons of mixed racial parentage affect the quality of the data. These are some of the issues that must be addressed as statistical agencies and researchers seek to provide comparable race and ethnic data.  相似文献   
2.
Nonorganic failure-to-thrive is a medical-psychological disorder reflecting lack of growth in an infant without apparent physical causes. Children who fail to thrive as infants are at high risk for developmental delays, personality problems, abuse, and death. This article focuses on environmental failure-to-thrive, describing the behavioral characteristics of the nonthriving infant and the family milieu. Aspects of early environments of NOFT infants are profiled, specific intervention strategies are discussed, and recommendations regarding the promotion of intense, consistent multi-disciplinary intervention strategies are advanced.  相似文献   
3.
The functional significance of the pars tuberalis (PT) of the mammalian adenohypophysis has remained an enigma (1, 2). One view of its function is that it acts as an auxiliary gland to support the endocrine role of the pars distalis (PD) (2), as it has been shown to contain immunocytochemically identifiable thyrotrophs and gonadotrophs (1). Many of the cells of the PT are, however, ultrastructurally unique suggesting an independent function for this tissue. Our recent demonstration that the PT of the rat is a major binding site for the ligand iodomelatonin lends further support to this idea (3). We have utilized the highly specific ligand [125l]melatonin, and have demonstrated that it binds exclusively, with very high affinity, to the PT but not the PD of the adult sheep adenohypophysis. These findings support the conclusion that the PT has a distinct role in relation to melatonin action and seasonal reproduction.  相似文献   
4.
Background: Primary afferent nociceptor sensitization and its accompanying spontaneous discharge are believed to be the proximate cause of the spontaneous pain and hypersensitivity that follow an acute tissue injury. Evidence for this comes almost entirely from studies limited to the first few minutes to an hour or two after injury, when the inflammatory reaction to injury has just begun. However, there is evidence that inflammatory pain mechanisms differ from acute pain mechanisms and that the mechanisms that drive and modulate inflammatory pain may evolve over time.

Methods: The authors surveyed spontaneous afferent discharge in rats with hind paw inflammation evoked by complete Freund adjuvant over the entire 14 days of the inflammatory pain condition, as determined in parallel experiments assessing allodynia and hyperalgesia.

Results: Inflammation-evoked heat hyperalgesia, mechanoallodynia, and mechanohyperalgesia began within hours, persisted until at least day 7, and resolved by day 14. A large percentage (23%) of A fibers had spontaneous discharge 2 days after inflammation, but the incidence was much reduced (to 7-9%) by 7 and 14 days. At all times, the A-fiber discharge frequency was low (<3.0 Hz) or very low (<0.3 Hz). A large percentage (24%) of C fibers had spontaneous discharge 2 and 7 days after inflammation, but this also declined to near control levels by day 14; C-fiber discharge frequency was also always low (most at 0.3-1.0 Hz).  相似文献   

5.
Hallucinations and associated factors in Alzheimer's disease.   总被引:1,自引:0,他引:1  
In a consecutive sample of 230 community-dwelling patients with probable Alzheimer's disease, a structured interview yielded evidence of current hallucinations in 29.1% and misperceptions in another 11.3%. Visual and auditory modalities were similarly represented in apparent hallucinations. Hallucinations prior to the current monitoring period were rare among patients with misperceptions or with no perceptual abnormality. The probability of hallucinations was associated with the severity of cognitive dysfunction, the degree of other behavioral disturbances, and the presence of extrapyramidal signs. A logistic regression model predicting hallucinations based on these diverse clinical features accurately classified 87.0% of the sample.  相似文献   
6.
7.
Exposing embryos to elevated temperatures both in vivo and in vitro has been shown to result in the production of offspring with severe congenital abnormalities. While a direct effect of heat cannot be excluded, recent interest has been focused on the possible role that the induction of the heat shock response may have in the etiology of the observed congenital defects. In the present study, mouse embryos from inbred strains known to differ in terms of their sensitivity to heat-induced exencephaly were treated in vivo and their heat shock response determined using SDS-PAGE electrophoretic techniques. Further, the embryonic responses were compared with a maternal cell type. We observed excellent agreement between the two test systems following exposure to a teratogenic hyperthermic insult. Both the embryonic and maternal cells underwent a reduction in total protein synthesis and an enhanced synthesis of four heat shock proteins migrating with the molecular weights of 68, 70, 97, and 110 kDa. The results failed to indicate any strong correlation between the heat shock response and enhanced genetic sensitivity to hyperthermia-induced neural tube defects.  相似文献   
8.
Autosomal dominant neovascular inflammatory vitreoretinopathy   总被引:1,自引:0,他引:1  
S R Bennett  J C Folk  A E Kimura  S R Russell  E M Stone  E M Raphtis 《Ophthalmology》1990,97(9):1125-35; discussion 1135-6
Twenty-eight of 61 members of a six-generation family are affected by an autosomal dominant eye disease which has not been described previously. Affected patients are asymptomatic in early adulthood, but have vitreous cells and the selective loss of the b-wave on the electroretinogram. Later, peripheral retinal scarring and pigmentation, peripheral arteriolar closure, and neovascularization of the peripheral retina at the ora serrata or occasionally neovascularization of the optic disc develop. Cystoid macular edema, vitreous hemorrhage, tractional retinal detachment, and neovascular glaucoma can cause profound visual loss. Vitrectomy reduces traction on the retina and allows for retinal reattachment. The role of argon laser photocoagulation or cryopexy in reducing the neovascular complications remains uncertain.  相似文献   
9.
10.
This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery.  相似文献   
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