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61.
Contraceptive use among South Asian women attending general practices in southwest London.
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Sonia Saxena Pippa Oakeshott Sean Hilton 《The British journal of general practice》2002,52(478):392-394
A cross-sectional survey of contraceptive practices was conducted among 180 South Asian women aged 16 to 50 years, attending inner-city general practices. Overall prevalence of contraceptive use was 63% and ranged from 70% in South Asian teenagers, to only 50% in women over 30 who had completed their family. Thirteen per cent of women had had a termination of pregnancy Although contraceptive use in this group is increasing, it has not yet reached national levels. 相似文献
62.
63.
Hussey SM Gander R Southern P Hoang MP 《Archives of pathology & laboratory medicine》2005,129(6):794-797
Primary subcutaneous phaeohyphomycosis can rarely be caused by Cladophialophora bantiana, and we present the histologic and culture findings of such a case. A 32-year-old African American woman with systemic lupus erythematosus presented with a 2-year history of multiple, recurrent, tender, and ulcerated skin nodules with purulent drainage on her upper back. Histologic sections of the excision demonstrated features of phaeohyphomycosis. Culture findings were characteristic of C bantiana. Of interest, at age 10 she had sustained traumatic implantation of wood splinters into this area during a tornado, yet clinical symptoms of a subcutaneous infection did not manifest until she developed lupus erythematosus at age 27. Our case highlights the role of trauma and immunosuppression in the pathogenesis of subcutaneous phaeohyphomycosis. 相似文献
64.
Fine-needle aspiration (FNA) is a reliable, safe, and cost-effective procedure with a well-established role in the diagnosis of various solid tissue neoplasms. The role of FNA in the diagnosis of primary bone tumors, including osteosarcoma (OGS), is controversial and has yet to be established. We reviewed our experience with the use of FNA as a diagnostic technique over the past 8 yr at our institution. Diagnosis was conclusive in 26 (65%) of 40 patients, 18 of whom went to neoadjuvant therapy and/or resection based solely on the FNA interpretation of either "high grade sarcoma" or "osteosarcoma." Of the remaining 14 (25%) patients, 12 had inconclusive diagnosis and two (5%) were false-negatives. An inconclusive diagnosis was most likely to be an inadequate or paucicellular aspirate, seen in six (15%) patients. An additional six patients had variants of osteosarcoma (four chondroid, one "giant cell rich," one parosteal) that made definitive diagnosis impossible. The two that were incorrectly classified were diagnosed as fracture callus and plasmacytoma. FNA is an accurate and cost-effective tool for the initial diagnosis of primary osteosarcoma with a sensitivity of 65% and accuracy of 95%. Inconclusive diagnoses are likely to be due to insufficient sample cellularity or the presence of OGS variant. In our experience, FNA is sufficient to provide the diagnosis of OGS prior to definitive treatment when interpreted in conjunction with imaging studies and clinical findings. In those cases where FNA fails to yield a diagnostic sample, a traditional biopsy can be performed. 相似文献
65.
Stroke-prone rat strains exhibit an increased stroke risk and sensitivity, and reduced endogenous mechanisms of ischemic brain tolerance. This experiment provides a comparative, serial evaluation of neurological deficits and brain injury following middle cerebral artery occlusion/permanent focal stroke in this high-risk strain. Stroke-prone spontaneously hypertensive (SHR-SP), spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats were evaluated over 28 days using magnetic resonance imaging (MRI), histopathology, and neurobehavioral testing. T2- and diffusion weighted-MRI was performed after 1, 10 and 28 days to measure the degree of stroke-induced brain injury. Normotensive WKY rats receiving the same stroke and other SHR-SP rats receiving sham surgery were used for control comparisons. Functional deficits were scored after 1, 4, 11, 18 and 28 days. The degree of brain infarction/injury was practically identical in hypertensive and stroke-prone rats. WKY rats exhibited significantly smaller infarcts (P<0.05), with neurological function recovering quickly to normal by day 11 in this strain. Functional deficits persisted longer in hypertensive rats, with function recovering to normal by day 18 (P<0.05). Functional deficits in SHR-SP rats persisted the longest, and were observed even after 28 days (P<0.05). This increased and prolonged neurologic dysfunction exhibited by SHR-SP compared to SHR rats, while exhibiting practically identical degrees of brain injury/infarction, reflects the increased stroke risk and sensitivity of this strain and suggests a reduced SHR-SP brain plasticity following injury. Therefore, the stroke-prone rat provides an enhanced and prolonged functional deficit model that can be used to elucidate those mechanisms/novel targets critical to longitudinal neurobehavioral recovery post-stroke. 相似文献
66.
Ginger L Chew Elizabeth J Carlton Daniel Kass Marta Hernandez Brian Clarke Julius Tiven Robin Garfinkel Sean Nagle David Evans 《Annals of allergy, asthma & immunology》2006,97(4):502-513
BACKGROUND: Asthma prevalence is high in the inner city, and morbidity has been associated with cockroach and mouse allergens. OBJECTIVE: To characterize the relationships among pests, allergens, pesticides, and asthma in New York City public housing. METHODS: In 324 apartments, dust samples collected from beds and kitchens were analyzed for cockroach (Bla g 2) and mouse (mouse urinary protein [MUP]) allergens, pest populations were monitored, and residents were interviewed about home characteristics and asthma symptoms. RESULTS: Cockroaches were found in 77% of the apartments, and evidence of mice was found in 13%. Allergens and pesticide use were associated with pest infestation, and 15% of residents reported using illegal pesticides. The percentage of apartments with high allergen levels varied significantly by building (Bla g 2: P = .002; MUP: P = .03), as did the percentage of apartments with cockroaches (P = .002) and daily mouse sightings (P = .02). Thirty-seven percent of the apartments had at least 1 resident with physician-diagnosed asthma. In family buildings, apartments with high Bla g 2 levels had 1.7 times greater odds of having an asthmatic resident (95% confidence interval, 1.2-2.3). In senior citizen buildings, apartments with high MUP levels had 6.6 times greater odds of having an asthmatic resident (95% confidence interval, 1.4-31.7), controlling for smoking and other potential confounders. CONCLUSIONS: Previous studies have identified home characteristics associated with the presence of cockroaches and mice, but the present findings suggest that building-level characteristics can affect high pest exposure. Furthermore, the high asthma prevalence in residents and the use of illegal pesticides highlight the need for safe and effective building-wide pest control strategies. 相似文献
67.
The neural basis of the psychomotor vigilance task 总被引:1,自引:0,他引:1
STUDY OBJECTIVE: To identify brain regions underlying the fastest and slowest reaction times on the Psychomotor Vigilance task (PVT) under well-rested conditions, as well as brain regions related to particularly poor performance after sleep deprivation. DESIGN: Subjects took the PVT twice while undergoing functional magnetic resonance imaging: once 12 hours after waking from a normal night of sleep and once after 36 hours of total sleep deprivation (TSD). Session order was counterbalanced. SETTING: UCSD J. Christian Gillin Laboratory for Sleep and Chronobiology (the sleep core of the General Clinical Research Center) and UCSD Magnetic Resonance Institute. PATIENTS OR PARTICIPANTS: Twenty right-handed healthy adults (8 women; age = 27.4 +/- 6.7 years; education = 15.6 +/- 1.5 years). MEASUREMENTS AND RESULTS: After a normal night of sleep, optimal performance was related to greater cerebral responses within a cortical sustained attention network and the cortical and subcortical motor systems. Slow reaction times, particularly after TSD, were associated with greater activity in the "default mode network" consisting of frontal and posterior midline regions. CONCLUSIONS: Optimal performance on the PVT appears to rely on activation both within the sustained attention system and within the motor system. Poor performance following TSD may result from a disengagement from the task and related inattention, and brain regions responsible for this localize within midline structures shown to be involved in the brain's "default mode." Finally, particularly poor performance after TSD may elicit a subsequent attentional recovery that manifests as greater activation within the same regions normally responsible for fast reaction times. 相似文献
68.
Synaptic vesicles were isolated on sucrose density gradients from perfused blocks of Torpedo electric organ under varying experimental conditions. Newly synthesized acetylcholine was labelled with [3H]acetate in order to distinguish synaptic vesicles which had been recycled during stimulation-induced transmitter release and, in consequence, had become smaller and denser from the larger, lighter vesicles characteristic of unstimulated tissue. After 1800 pulses at 0.1 Hz, the density of these smaller vesicles increased from a pre-stimulation value of 1.056 g.ml?1 to 1.067 g.ml?1, whereas their water space (measured as the space occupied by the permeant solute glycerol), decreased by 34% from 65% to 43% of vesicle volume. During a subsequent 12 h rest period, these changes were partially reversed; water space returned to 52% of control and this change was highly correlated with a decrease in vesicle density and an increase in vesicular acetylcholine. The diameter of vesicles in whole tissue sections showed corresponding changes. An additional 12 h rest period did not lead to further significant recovery, suggesting that the preparation had a limited suitability for following long term processes depending on normal energy metabolism.The results can be explained on the assumption that when vesicles reform after releasing transmitter their core has a lower osmotic pressure than that of fully loaded vesicles. Reloading is accompanied by osmotically induced rehydration. 相似文献
69.
Ungsedhapand C Srasuebkul P Cardiello P Ruxrungtham K Ratanasuwan W Kroon ED Tongtalung M Juengprasert N Ubolyam S Siangphoe U Emery S Lange JM Cooper DA Phanuphak P;HIV-NAT HIV-NAT Study Team 《Journal of acquired immune deficiency syndromes (1999)》2004,36(2):693-701
We compared the long-term immunologic and virologic efficacy of the dual- and triple-nucleoside therapy for HIV infection. This was a retrospective analysis of 2 randomized clinical trials in antiretroviral-naive patients. In the dual-nucleoside group, 15 started with didanosine (ddI) monotherapy and then added stavudine (d4T) after 24 weeks, 63 started with various doses of d4T and ddI, and 53 started with zidovudine (ZDV) and lamivudine (3TC). In the triple-nucleoside group, 53 started with ZDV, 3TC, and ddI. After 48 weeks, patients who were not failing were randomized to immediate (before treatment failure) versus delayed (at the time of virologic failure) switching from ddI and d4T to ZDV and 3TC or vice versa and from ZDV, 3TC, and ddI to d4T, 3TC, and abacavir (ABC). Failure was defined as a plasma HIV-1 RNA level>or=1 log10 above nadir or >or=10,000 copies/mL when nadir was <500 copies/mL. Patients failing therapy before week 48 received the new treatment as in the immediate switching group. Hydroxyurea was added to the last treatment regimen if patients failed after week 96. CD4 count and plasma HIV-1 RNA level (branched DNA assay with a cutoff point of 50 copies/mL) at week 144 were analyzed by intention to treat. Compared with the dual-nucleoside group, the triple-nucleoside group had a higher proportion of patients with <50 copies/mL at 144 weeks (60% vs. 18%; P<0.001), higher median CD4 count (388 cells/microL vs. 346 cells/microL; P=0.018), and longer duration of response, defined as the time from onset of viral suppression (<500 copies/mL) to the time of treatment failure (the first of 2 consecutive HIV-1 RNA measurements >500 copies/mL never followed by 2 consecutive visits showing suppressible viremia to <500 copies/mL) or discontinuation from the study (144 weeks vs. 104 weeks; P=0.002). Multivariate regression analyses showed that significant predictors for treatment success, defined as a plasma viral load <50 copies/mL at week 144, were asymptomatic clinical status at enrollment, a baseline plasma viral load 相似文献
70.