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61.
Accurate measurements of HIV prevalence and associated risk factors among hidden and high-risk groups are vital for program planning and implementation. However, only two sampling methods are purported to provide representative estimates for populations without sampling frames: time-location sampling (TLS) and respondent-driven sampling (RDS). Each method is subject to potential biases and questionable reliability. In this paper, we evaluate surveys designed to estimate HIV prevalence and associated risk factors among people who inject drugs (PWID) sampled through TLS versus RDS. In 2012, males aged ≥16 years who reported injecting drugs in the previous month and living in Haiphong, Vietnam, were sampled using TLS or RDS. Data from each survey were analyzed to compare HIV prevalence, related risk factors, socio-demographic characteristics, refusal estimates, and time and expenditures for field implementation. TLS (n = 432) and RDS (n = 415) produced similarly high estimates for HIV prevalence. Significantly lower proportions of PWID sampled through RDS received methadone treatment or met an outreach worker. Refusal estimates were lower for TLS than for RDS. Total expenditures per sample collected and number of person-days of staff effort were higher for TLS than for RDS. Both survey methods were successful in recruiting a diverse sample of PWID in Haiphong. In Vietnam, surveys of PWID are conducted throughout the country; although the refusal estimate was calculated to be much higher for RDS than TLS, RDS in Haiphong appeared to sample PWID with less exposure to services and required fewer financial and staff resources compared with TLS.  相似文献   
62.
Humans who work in Antarctica display deficits in cognition, disturbances in mood, increased energy requirements, a decline of thyroid hormone products, and an increase of serum TSH. We compared measurements in 12 subjects, before deployment (baseline), with 11 monthly studies during Antarctic residence (AR). After 4 months of AR (period 1), half of the subjects (T(4) group) received L-thyroxine [64 nmol.day(-)(1) (0.05 mg.day(-)(1))]; and the other half, a placebo (placebo group) for the next 7 months of AR (period 2). During period 1, there was a 12.3 +/- 5.1% (P < 0.03) decline on the matching-to-sample (M-t-S) cognitive task and an increase in depressive symptoms, compared with baseline. During the intervention in period 2, M-t-S scores for the T(4)-treated group returned to baseline values; whereas the placebo group, in contrast, showed a reduced M-t-S score (11.2 +/- 1.3%; P < 0.0003) and serum free T(4) (5.9 +/- 2.4%; P < 0.02), compared with baseline. The change in M-t-S score was correlated with the change in free T(4) (P < 0.0003) during both periods, and increases in serum TSH preceded worsening scores in depression, tension, anger, lack of vigor, and total mood disturbance (P < 0.001) during period 2. Additionally, the submaximal work rate for a fixed O(2) use decreased 22.5 +/- 4.9% in period 1 and remained below baseline in period 2 (25.2 +/- 2.3%; P < 0.005) for both groups. After 4 months of AR, the L-thyroxine supplement was associated with improved cognition, which seems related to circulating T(4). Submaximal exercise performance decrements, observed during AR, were not changed with this L-thyroxine dose.  相似文献   
63.
Tetanus is a preventable disease that continues to affect people in both developing and developed countries. The aim of the present study was to evaluate the immunity profile to tetanus in patients with Type II diabetes mellitus (DM) and to compare them with healthy controls. The tetanus antitoxin levels in 310 diabetic patients (104 males and 206 females) and in 200 healthy controls (72 males and 128 females) were measured by ELISA (Virotech, Germany). The mean antitoxin concentration in patient and control groups were 0.8238+/-1.61 and 0.9978+/-1.49 IU/ml, respectively. There was a statistically significant difference between the two groups (z=-3.520, P=.0001 and odds ratio was 2.367). There was a definitive inverse correlation between the duration of diabetes and tetanus antibody titers (Spearman's correlation analysis, r=-.155, P=.006). A gender-dependent difference in the susceptibility to tetanus was present in the diabetic group with antibody titers being significantly higher in males compared with females (z=-2.267, P=.023). For both of control (chi(2)=20.207, P=.003) and patient (chi(2)=43.532, P=.0001) groups, there was a significant inverse correlation between the tetanus immunity levels and age. Statistically, a significant drop in antibody titers of both groups was found as the period past from the last immunization increased (Pearson correlation analysis: for patient group r=-.364, P=.0001; for control group r=-.143, P=.044). The tetanus antitoxin levels were significantly increased in individuals who had primary immunization during childhood (for patient group chi(2)=17.191, P=.0001; for control group chi(2)=9.911, P=.007). A significant reduction in the level of antitoxin immunity to tetanus in association with an increased susceptibility to infections in patients with diabetes may implicate the need for improving vaccination rates in this patient group.  相似文献   
64.
65.
Right ventriculography with a preshaped catheter (J- or L-shaped) was evaluated in make the diagnosis of tricuspid regurgitation. Thirty normal subjects who did not have valvular disease showed no evidence of tricuspid regurgitation or premature ventricular contractions during injection except in one case. On the other hand, 24 patients with combined aortic and mitral valve disease showed mild to moderate tricuspid regurgitation in 11 patients and severe tricuspid regurgitation in eight patients. Only two patients developed frequent run of premature ventricular contraction during injection. Seven patients with severe tricuspid regurgitation were found to have severe tricuspid regurgitation during surgery. No evidence of tricuspid regurgitation was found In all six patients with isolated aortic valve disease. We can conclude that right ventriculography by the preshaped catheter improves the diagnostic accuracy of tricuspid regurgitation and a grading system of tricuspid regurgitation by angiography is proposed.  相似文献   
66.
ABSTRACT: The low level of amphotropic retrovirus mediated gene transfer into human hematopoietic stem cells (HSC) has been an impediment to gene therapy for hematopoietic diseases (1). We have previously shown that mouse and human HSC have low levels of the mRNA encoding PiT-2, the amphotropic retrovirus receptor. We hypothesized that the low level of PiT-2 mRNA was responsible for the low frequency of transduction of HSC by amphotropic retroviral vectors (2). In this study we compared the level of PiT-2 and PiT-1, the Gibbon Ape Leukemia Virus receptor (GaLV), in 5 human tissue culture cell lines. PiT-2 and PiT-1 mRNA levels were highest in K562 cells and lowest in HL60 cells. In hematopoietic cell lines, the level of PiT-2 or PiT-1 mRNA correlated directly with retrovirus binding and transduction with the appropriate (amphotropic or GaLV) retrovirus vector. The level of expression of PiT-2 and PiT-1 mRNA could be increased by treatment of HL60 cells with either PMA or Interleukin-1α. The increase in the level of PiT-2 and PiT-1 mRNA correlated with increased transduction with both amphotropic and GaLV retroviral vectors. We conclude that the improved transduction was a direct effect of the increased levels of receptor mRNA and unrelated to changes in the cell cycle status.  相似文献   
67.
Arteriovenous malformations (AVMs) are direct communications between primitive reticular networks of dysplastic vessels that have failed to mature into capillary vessels. Based on angiographic findings, peripheral AVMs can be classified into six types: type I, type IIa, type IIb, type IIc, type IIIa, and type IIIb. Treatment strategies vary with the types. Type I is treated by embolizing the fistula between the artery and the vein with coils. Type II (IIa, IIb, and IIc) AVM is treated as follows: first, reduce the blood flow velocity in the venous segment of the AVM with coils; second, perform ethanol embolotherapy of the residual shunts. Type IIIa is treated by transarterial catheterization of the feeding arteries and injection of diluted ethanol. Type IIIb is treated by transarterial or direct puncture approaches. A high concentration of ethanol is injected through the transarterial catheter or direct puncture needle. When the fistula is large, coil insertion is required to reduce the amount of ethanol. Type I and type II AVMs showed the best clinical results; type IIIb showed a satisfactory response rate. However, type IIIa showed the poorest response rate, either alone or in combination with other types. Clinical success can be achieved by using different treatment strategies for different angiographic AVM types.  相似文献   
68.
69.

Purpose

Endobronchial metastasis is defined as documented extrathoracic malignancies metastatic to the endobronchus within a bronchoscopically visible range. Although the clinical and radiologic findings of endobronchial metastasis are similar to primary lung cancer, treatment and prognosis may be different. We hereby investigated the clinical, radiologic and bronchoscopic aspects of endobronchial metastases (EBM) in Korean patients.

Materials and Methods

A total of 43 patients with EBM who underwent bronchoscopic biopsies from June 1991 to December 2009 at Severance Hospital, Yonsei University College of Medicine in Seoul, Korea, were analyzed retrospectively. We evaluated clinical, radiologic and bronchoscopic characteristics of EBM.

Results

The patients consisted of 27 males and 16 females and their ages ranged from 18 to 77 years. The common primary cancers related to EBM were rectal (16.3%), colon (11.6%), breast (9.3%) and uterine (9.3%) cancers. The mean interval from diagnosis of primary cancer to EBM was 36 months, and the mean survival duration from diagnosis of EBM was 16.1 months in 33 deceased patients.

Conclusion

EBM develop in various types of malignancies at various times with unremarkable manifestations. Therefore, physicians should consider the possibility of EBM, especially if a patient has a history of any malignancy, regardless of respiratory symptoms. Respiratory symptoms related with EBM can be treated by various safe procedures.  相似文献   
70.

Purpose

The palatal mucosa is a major donor site for connective tissue in the field of periodontal plastic surgery, since it satisfies both the esthetic and functional demands of patients. The purpose of this study was to use histomorphometric analysis to measure the thicknesses of the palatal mucosa and the lamina propria including the epithelium on cadavers.

Methods

Thirty-four hemimaxillae of cadavers were examined (13 male and 4 female, mean age 57.2 years). Each maxilla was processed for histological sectioning and subsequently for histomorphometric analysis. The thicknesses of the palatal mucosa and the lamina propria including the epithelium were measured at three points starting from the alveolar crest, at intervals of 4 mm, with the aid of Adobe Photoshop.

Results

The thickness of the palatal mucosa at the alveolar crest and at 4 and 8 mm below the alveolar crest were 2.51 ± 0.83 (mean ± SD), 2.92 ± 0.80, and 3.62 ± 0.99 mm, respectively, and thus increasing from the alveolar crest toward the midpalatal suture. Conversely, the thicknesses of the lamina propria including the epithelium at these same positions were 2.06 ± 0.70, 1.54 ± 0.48, and 1.28 ± 0.46 mm, respectively, thus decreasing toward the midpalatal suture.

Conclusions

The present results indicate that clinicians need to be particularly careful when harvesting palatal mucosa that is destined to be used as autogenous donor material for connective tissue in periodontal plastic surgery.  相似文献   
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