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71.
This study examined the barriers and facilitators of HIV counseling, testing, and referral service (HIV CTR) acceptance among 278 youth aged 12-24 years old. Participants completed a questionnaire before health education sessions with trained counselors. Information was collected on individual characteristics, HIV testing acceptance, risk behaviors, reasons for having never been tested, and what would make it easier to get tested for HIV. Ninety percent of the respondents were minority and 52% were female with an average age of 15 years. High-risk minority youth who had never received HIV CTR listed low perception of risk and never having been offered a test as reasons for not having been tested. Increased availability of oral and rapid testing methods as well as free testing services were listed as facilitating their acceptance of HIV testing. Older youth aged 18-24 years reported that HIV tests in which results can be received rapidly and confidentially would encourage them to obtain HIV testing services. Early identification approaches should be tailored to increase the access to and acceptance of HIV-testing services among the adolescent and young adult populations.  相似文献   
72.
We studied the relationships between magnetic resonance imaging (MRI) findings and neuropsychological sequelae in children after severe traumatic brain injury. Twenty-three children ages 7-13 years underwent MRI assessment of brain lesion topography and volume and neuropsychological evaluations, more than 1 year after sustaining severe traumatic brain injury. Most children had lesions to the corpus callosum and frontal lobes. Total lesion volume and extent of cerebral atrophy did not impact on the neuropsychological evaluation. Additional relationships were observed: left frontal lesions with lower semantic verbal fluency, right occipital lesions with lower visual recognition task scores, dyscalculia with cerebellar lesions, and cerebellar damage with lower cognitive performances and lower visual recognition memory. This study demonstrates the significance of the cerebellum's role in neuropsychological outcomes after traumatic brain injury and the importance of the lesion depth classification in predicting functional results.  相似文献   
73.
Uncaria tomentosa (Willd.) DC (Rubiaceae) is a large woody vine that is native to the Amazon and Central American rainforests and is used widely in traditional medicine for its immunomodulatory and antiinflammatory activities. The present work used in vivo immunotoxic and in vitro immunomodulatory experiments to investigate the effects of a pentacyclic oxindole alkaloid extract from U. tomentosa bark on lymphocyte phenotype, Th1/Th2 cytokine production, cellular proliferation and cytotoxicity. For the in vivo immunotoxicity testing, BALB/c male mice were treated once a day with 125, 500 or 1250 mg/kg of U. tomentosa extract for 28 days. For the in vitro protocol, lymphocytes were cultured with 10–500 μg/mg of the extract for 48 h. The extract increased the cellularity of splenic white pulp and the thymic medulla and increased the number of T helper lymphocytes and B lymphocytes. Also, a large stimulatory effect on lymphocyte viability was observed. However, mitogen‐induced T lymphocyte proliferation was significantly inhibited at higher concentrations of U. tomentosa extract. Furthermore, an immunological polarization toward a Th2 cytokine profile was observed. These results suggest that the U. tomentosa aqueous‐ethanol extract was not immunotoxic to mice and was able to modulate distinct patterns of the immune system in a dose‐dependent manner. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
74.
Large conductance voltage- and calcium-activated potassium channels (MaxiK, BKCa) are well known for sustaining cerebral and coronary arterial tone and for their linkage to vasodilator β-adrenergic receptors. However, how MaxiK channels are linked to counterbalancing vasoconstrictor receptors is unknown. Here, we show that vasopressive thromboxane A2 receptors (TP) can intimately couple with and inhibit MaxiK channels. Activation of the receptor with its agonist trans-inhibits MaxiK independently of G-protein activation. This unconventional mechanism is supported by independent lines of evidence: (i) inhibition of MaxiK current by thromboxane A2 mimetic, U46619, occurs even when G-protein activity is suppressed; (ii) MaxiK and TP physically associate and display a high degree of proximity; and (iii) Förster resonance energy transfer occurs between fluorescently labeled MaxiK and TP, supporting a direct interaction. The molecular mechanism of MaxiK–TP intimate interaction involves the receptor''s first intracellular loop and C terminus, and it entails the voltage-sensing conduction cassette of MaxiK channel. Further, physiological evidence of MaxiK–TP physical interaction is given in human coronaries and rat aorta, and by confirming TP role (with antagonist SQ29,548) in the U46619-induced MaxiK inhibition in human coronaries. We propose that vasoconstrictor TP receptor and MaxiK-channel direct interaction facilitates G-protein–independent TP to MaxiK trans-inhibition, which would promote vasoconstriction.  相似文献   
75.
IntroductionDespite exhibiting histological differences from the human process, canine hormone-induced benign prostatic hyperplasia (BPH) is still the most widely used animal model for evaluating treatment strategies.ObjectivesThe aim of this study is to determine the optimal moment for starting a therapeutic trial in this animal model.Material and methodsSix male beagle dogs over one year of age were used in this study. All animals received a combination of steroid hormones, namely 17β-estradiol and 5α-androstene 3α 17β-diol, every other day during three (Group 1, n=3) or five months (Group 2, n=3). Transrectal ultrasonographic examinations to measure prostate volume were performed monthly. Animals were euthanized after five months for histological study of their prostates.ResultsAll animals developed BPH, with prostate volume increasing over time as hormones were administered (r=0,910). All ultrasonographic studies performed up to the third month evidenced a significant increase in prostate volume when compared to the prior ultrasound measurement. A significant decrease in prostate volume was seen in Group 1 once hormone administration was interrupted, whereas Group 2 animals showed a continuing increase in prostate size. Histological examination showed almost no evidence of BPH in Group 1 animals, while Group 2 animals clearly exhibited moderate epithelial hyperplasia.ConclusionsThe administration of a combination of steroid hormones is effective in inducing benign prostatic hyperplasia in canines, but this hyperplasia disappears when hormone treatment is interrupted. In order to be useful for experimental studies, hormones should be administered for at least three months before commencing any treatment, and they should be continued throughout the length of the study..  相似文献   
76.
Stress has long been suspected to play a role in the etiology of many diseases and may be detrimental to health. Nowadays, the communication between the neuroendocrine and the immune systems is well established and there is enough evidence that the magnitude of stress-associated immune dysregulation is large enough to have health implications. In stress conditions, modulation of the immune system by the central nervous system (CNS) is mediated by a complex network of signals, showing a relationship between stress and resistance to infection. On the other hand, an adequate balanced diet plays a crucial role in the management of stress, and nutrition seems to be a critical determinant in the interactions among CNS and the immune system under stress conditions. Thus, interactions among nutrition, CNS and the immune system could be a key to understand implications in physiological stress situations. The present article will briefly review nutrition approaches on stress-related immune response and CNS communication.  相似文献   
77.

In the present study are depicted valuable observations for practitioners, obtained from an in vitro study which aims to evaluate the compressive strength of occlusal veneers fabricated from 3 type of restorative materials, before and after 1 month of acidic artificial saliva exposure (pH = 2.939). In this context, 90 extracted human molars were prepared to receive computer-aided design/computer-aided manufacturing (CAD/CAM) occlusal veneers. The restorative materials considered in this study were: Cerasmart; Straumann Nice and Tetric CAD. The occlusal veneers were designed, milled and cemented with an adhesive dual-cure resin cement. From all the extracted human molars, only sixty specimens were immersed in acidic artificial saliva, for 1 month, at 37 °C ± 1 °C and part of this specimens were also thermo-cycled, between 5 and 55 °C ± 2 °C, before compressive strength test. The results showed a lower compressive strength for both the samples exposed to acidic artificial saliva as well as for the samples exposed to acidic artificial saliva and thermo-cycled. Scanning electron microscopy (SEM) showed that after compressive strength, all the specimens non-exposed to acidic artificial saliva, present extensive cracks formation at the surface of the restorations, and after exposure to acidic artificial saliva for 1 month, the surface damage was characterized by longitudinal and profound fractures of the restoration, as well as the fracture of the tooth structure. Between CAD/CAM materials tested, nanoceramic resin shows more favorable fracture patterns, both before and after acidic artificial saliva exposure.

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78.
79.
The knowledge about lipid profile particularities in patients with atheromatous cardiovascular diseases may have therapeutic and prophylactic implications. MATERIAL AND METHOD: Study included patients with acute myocardial infarction (IMA) and stroke (AVC), cared in Cluj-Napoca's hospitals. RESULTS: The patients with IMA were from urban area in 76% of cases, 72% were males and 58% had arterial hypertension to. Cholesterolemia over 240 mg% level had 11.9% of patients (17.2% female, 9.8% male with IMA), HDL-cholesterolemia less then 35 mg% had 33.4% of male patients and less then 45 mg%, 64.1% of female IMA patients. Patients with AVC were only male who provided in 59% of cases from urban area, had age average of 63 years old, and 82% of them had arterial hypertension to. The average levels for cholesterol were higher in AVC patients (218.6 mg% from urban area, 211.3 mg% from rural area), for triglycerides were higher in patients with IMA and AVC from urban area. High average level of HDL-cholesterolemia had patient with antecedent alcohol consuming (49.5 mg%), women with IMA (45.09 mg %) and in contrast the smokers had the lowers levels (38.37 mg%).  相似文献   
80.
Steroids are still the mainstay of therapy in primary chronic glomerulonephritis (PCGN), regardless of underlying disturbance or pathology. Moreover, relationship between known abnormalities and disease manifestation is stochastic, therefore treatment continues to be empirical. It is not known whether responsiveness is related to immune phenotype. We performed flowcytometric lymphocyte (Ly) phenotyping (CD19, CD3, CD3CD4, CD3CD8, CD56/16) on 16 patients (pts) (12M, 4F), mean age 37.6+/-13 years with primary chronic glomerulonephritis (PCGN): minimal change disease (MCD)--6 pts, focal and segmental glomerulosclerosis (FSGS)--4 pts, mesangial proliferative glomerulonephritis--5 pts, mesangiocapillary glomerulonephritis--1 pt, before and at 7 days of oral Prednisone 1 mg/kg/day (in 2 divided doses). Before steroids: 4/16 pts(25%) had elevated BP; 9/16(56.2) showed nephrotic proteinuria. Serum creatinine was >1.2 mg% in 6/16(37.5%). At 7 days WBC count increased (13,079.37+/-4966.4/microl vs. 8021.25+/-2077.4/microl; p=0.0007), Ly percentage (%) decreased (20.30+/-9% vs. 29.9+/-10.4%; p=0.0095), while absolute (abs.) Ly count remained unchanged. Both CD19 Ly% and CD19 Ly abs. count increased (16.13+/-6.5% vs. 9.52+/-3.7%; p=0.0015, and 410.012+/-29.7/microl vs. 223.56+/-123.8/microl; p=0.0077, respectively). NK (natural killer)% decreased (9.15+/-5.2% vs. 14.19+/-7.1%; p=0.0296). CD3, CD3CD4, CD3CD8 Ly subsets and CD4/CD8 ratio showed no change. Variation in proteinuria (2.88+/-2.1 g/24 h vs. 3.45+/-1.7 g/24 h; p=0.4) did not reach statistical significance (Wilcoxon-Mann-Whitney). In 11 pts we performed an additional analysis at 1 month. Compared to levels before steroids, there was an increase in WBC, CD19 Ly% and CD19 Ly abs. count and a decrease in NK% and NK abs. count. Other Ly subsets and CD4/CD8 ratio remained unchanged. Variation in clinical parameters (proteinuria, serum Creatinine, BP) did not reach statistical significance. Changes in Ly profile precede changes in clinical parameters and thus are divergent. While our patients proved to be early non-responders, further studies to elucidate whether profile changes provide for response specification are warranted.  相似文献   
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