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1.
The prevalence of human herpesvirus 8 (HHV-8)/Kaposi's sarcoma (KS)-associated herpesvirus was investigated in the semen of 99 human immunodeficiency virus (HIV)-infected men (median CD4 cell count, 357/mm3) by use of a polymerase chain reaction (PCR) assay capable of detecting <10 copies of HHV-8 DNA. Of the subjects, 95 (96%) self-identified as men who have sex with men (MSM), and 3 had a history of clinical KS. Seminal cell specimens were negative for HHV-8 in 98 subjects. None of the 26 without KS (27.1% of 96 tested) who were seropositive for HHV-8 by IFA for latency-associated nuclear antigens had HHV-8 detected in their semen. The only subject with any evidence for seminal HHV-8 DNA was seropositive for HHV-8 and had active KS. HHV-8 was detected in 10 (10.4%) of 96 peripheral blood mononuclear cell specimens. The prevalence of HHV-8 DNA by PCR in semen of HIV-infected MSM without KS is low.  相似文献   
2.
This study is an attempt to analyze the relationships between EEG and dermatoglyphic patterns (DP) in 6-8 years girls. EEG-mapping was carried out in 80 healthy girls with different types of DP in 6 frequency band: delta, theta, alpha-1, alpha-2, alpha-3 and beta. Certain connection of the palmar and finger patterns with the EEG characteristics was revealed. The most pronounced differences were observed between subgroups with prevalence (8 and more) or absence of whorls on their hands fingertips, and between groups with presence or absence of certain pattern (whorl, loop or vestige) on thenar/interdigital 1 area (Th/1). Significant (p<0.05) increase of spectral density in alpha-2 and alpha-3 bands in children with whorls on hand fingertips were revealed in the first case. EEG of children with Th/1 pattern differed from the group without such pattern by increased spectral density in alpha-2, alpha-3 and beta bands. The new data obtained support the genetic determination of the EEG.  相似文献   
3.
More than 200 individual particles within a portland scement paste were morphologically categorized by backscatter SEM and analyzed systematically by EDXA. Nearly all of the analyses fall either in a dense cluster around a mean C-S-H gel composition or along tie lines connecting this composition to theoretical compositions for calcium hydroxide, monosulfate, ettringite, and ferrite. "Phenograin" C-S-H gel (formed as a direct replacement product within large cement grains) contains small amounts of Al, Fe, and S, but otherwise shows almost negligible compositional variation. In contrast, smaller groundmass particles and shells of gapped phenograins show a slightly differentc S-H gel composition. Some of these, despite being morphologically homogeneous, show compositions falling along tie lines to the other recognized phases. This is attributed to extensive occurrence of intimate mixtures of C-S-H gel with the other components below the scale of SEM observation. Ionic substitutions appear to be minor except for the monosulfate and ettringite components in such mixtures. These show a variable but usually high deficiency in the sulfate content.  相似文献   
4.
The purpose of this study was to investigate the temporal relationships of the transport of β-carotene in human lipoproteins. We administered 60 mg β-carotene with breakfast to nine fasting subjects, then blood samples were collected at intervals of up to 75 h, lipoproteins were isolated, and β-carotene was quantitated. β-Carotene concentrations in chylomicrons and very low density lipoproteins (VLDL) peaked at 6 and 9 h, respectively. Nonetheless, at all time points the majority of plasma β-carotene was contained in low density lipoproteins (LDL), while high density lipoproteins (HDL) carried a smaller portion (at 24 h, 73±8% in LDL as compared with 23±5% in HDL). In three subjects, transport of β-carotene was compred with the results of earlier studies on the transport of stereoisomers of α-tocopherol. Unlike plasmaRRR-α-tocopherol concentrations, which are maintained by the preferential incorporation ofRRR-α-tocopherol into VLDL by the liver, β-carotene increased and decreased in VLDL similarly toSRR-α-tocopherol, a stereoisomer whose concentrations are not maintained in plasma. In conclusion, β-carotene is primarily transported in the plasma in LDL, but its incorporation by the liver into lipoproteins does not appear to be enhanced.  相似文献   
5.
OBJECTIVES: This study assessed the incremental prognostic implications of normal and equivocal exercise technetium-99m (Tc-99m) sestamibi single-photon emission computed tomography (SPECT) and sought to determine its incremental prognostic value, impact on patient management and cost implications. BACKGROUND: The prognostic implications of Tc-99m sestamibi SPECT are not well defined, and risk stratification using this test has not been explored. METHODS: We studied 1,702 patients referred for exercise Tc-99m sestamibi SPECT who were followed up for a mean (+/- SD) of 20 +/- 5 months. Patients with previous percutaneous transluminal coronary angioplasty or coronary artery bypass surgery were excluded. The SPECT studies were assessed using semiquantitative visual analysis. Cardiac death and myocardial infarction were considered "hard" events, and coronary angioplasty and bypass surgery > 60 days after testing were considered "soft" events. RESULTS: Of the 1,702 patients studied, 1,131 had normal or equivocal scan results. A total of 10 events occurred in this group (1 cardiac death and 1 myocardial infarction [0.2% hard events]; 4 coronary angioplasty and 4 bypass surgery procedures [0.7% soft events]). The rates of hard events and referral to catheterization after SPECT were similarly low in patients with a low (< 0.15), intermediate (0.15 to 0.85) and high (> 0.85) post-exercise treadmill test (ETT) likelihood of coronary artery disease. With respect to scan type, patients with normal, probably normal or equivocal scan results had similarly low hard event rates. In the 571 patients with abnormal scan results, there were 43 hard events (7.5%) and 42 soft events (7.4%) (p < 0.001 vs. 1,131 patients with normal scan results for both). When the complete spectrum of scan responses was considered, SPECT provided incremental prognostic value in all patient subgroups analyzed. However, the nuclear scan was cost-effective only in patients with interpretable exercise ECG responses and an intermediate to high post-ETT likelihood of coronary artery disease and in those with uninterpretable exercise ECG responses and an intermediate to high pre-ETT likelihood of coronary artery disease. CONCLUSIONS: Normal or equivocal exercise Tc-99m sestamibi study results are associated with a benign prognosis, even in patients with a high likelihood of coronary artery disease. Although incremental prognostic value is added by nuclear testing in all patient subgroups, a testing strategy incorporating nuclear testing proved to be cost-effective only in the groups with an intermediate to high likelihood of coronary artery disease before scanning.  相似文献   
6.
Recent research has shown that multilayer feedforward networks with sigmoidal activation functions are universal approximators, and that this holds for more general activations as well. The mathematical underpinning for these results has been various: Kolmogorov's resolution of Hilbert's thirteenth problem; the Stone-Weierstrass theorem; approximation of Fourier and Radon integral representations; and convergence of probability measures. This paper
  Rigorously establishes the robustness of feedforward network realizations.
  Uses a theorem of Wiener and ideas of translation invariant subspaces to provide conditions for universal approximations toL 1 andL 2 functions by networks, for quite general activation functions.
The second result extends and simplifies some of the recent results of Stinchcombe and White, at least for the special cases ofL 1 andL 2 functions.  相似文献   
7.
The authors used rats to study the impact of a history of opiate exposures on behavioral and autonomic responses to restraint stress. Brief restraint (30 min) provoked tachycardia and a pressor response, anxiety (as indexed by social interaction), grooming, and reduced exploration. The pressor response was reduced at 1 day, but not 7 days, after last opiate exposure; tachycardia was unaffected (Experiment 1). Stress-induced anxiety was potentiated 1 and 7 days after last opiate exposure (Experiment 2), and this potentiation was a function of dose (Experiment 3) and duration (Experiment 4) of opiate exposure. The results show that a history of opiate exposures alters vulnerability to stress and has implications for understanding coping, anxiety, and emotionality in former opiate users. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Research shows that low albumin is correlated with higher morbidity and mortality in the dialysis population. The reasons for this are multi‐factorial and may be related to inadequate protein intake, infection and sepsis, inadequate dialysis, or catabolism of uremia. USRDS data show that ESRD Network 16 tends to have lower albumins compared to other ESRD Networks. Objective: To evaluate albumin status of HD patients at Puget Sound Kidney Centers, Everett, WA (ESRD Network 16) and identify potential factors that may put patients at risk of hypoalbuminemia. Methods: Clinical and biochemical data were collected for 3 months on 221 HD patients. Data included serum albumin (bromcresol purple), calcium, phosphorus, CO2, Hct, % saturation, ferritin, PTH, BUN, Kt/V, URR, nPCR, hours of HD treatment, interdialytic fluid weight gains, DW changes, incidence of infection and hospitalization, catheter use for dialysis access, presence of diabetes and other co‐morbidities, dialyzer reuse, social/psychological status, and use of nutrition supplements. All biochemical data were collected after the longest interdialytic period and analyzed at the same reference laboratory. Data were averaged for each patient for the 3 months and correlations between parameters were determined using Chi‐square analysis. Results: 25% of all patients had albumins <3.2 g/dL (reference range for normal population 3.5–5.0 g/dL). Patients with lower albumins were significantly more likely to have DM (p < 0.02), use catheters for HD access (p < 0.001), had infections during the previous month (p < 0.001), been hospitalized during the previous month (p < 0.002), have co‐morbid issues (p < 0.001), and use nutrition supplements (p < 0.002). No other factors were significantly correlated with lower albumin. Conclusion: Factors other than nutrition seem to be related to hypoalbuminemia. This study has prompted improved protocols for catheter care and use, infection control, and early intervention for nutrition supplement use. Increased screening and monitoring at‐risk patients (those with diabetes and other co‐morbid conditions) has resulted in improved patient care.  相似文献   
9.
The purpose of the current study was to examine in detail the association between witnessing domestic violence (DV) and long-term psychological adjustment. Important limitations of past research were addressed, including controlling for several associated risk factors. Special attention was paid to whether the perpetrator of the violence was the maternal or paternal figure, as well as to whether the witness to the violence was male or female. Participants completed measures examining DV witnessed, direct child abuse experienced, and current psychopathology. Following screening for physical and sexual abuse, a sample of 351 individuals was selected. Four groups of participants were compared. Results indicated that individuals who had witnessed either physical DV or major psychological DV had higher levels of psychopathology than individuals who reported witnessing minor psychological DV or controls. After controlling for direct psychological abuse experienced, witnessing DV remained a significant predictor of psychopathology for males but not for females. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
The author investigates the psychoanalytic implications of recent attachment research on the disorganized attachment category in infants and the unresolved for trauma and loss adult attachment classification with which it has been associated. The author first reviews empirical findings on attachment disorganization and then explores the ways in which they are consistent with and illuminated by psychoanalytic concepts. The focus is on linkages between disorganized attachment and Freud's theory of strain trauma and traumatic anxiety, Klein's theory of projective identification and the interplay between paranoidschizoid and depressive anxieties in development, and Blatt's theory of psychological development as resulting from the interplay of anaclitic and introjective developmental lines. In so doing, this article contributes to the reunion between attachment theory and psychoanalysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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