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71.
Radiological evaluation of internal abdominal hernias.   总被引:1,自引:0,他引:1  
An internal abdominal herniation is the protrusion of a viscus through a normal or abnormal mesenteric or peritoneal aperture. Internal abdominal herniations can either be acquired through a trauma or surgical procedure, or constitutional and related to congenital peritoneal defects. Paraduodenal hernias are the most common type of internal abdominal hernias, accounting for over one-half of reported cases, and thus are a significant clinical entity. Other internal hernias include pericecal, transmesenteric, transomental, intersigmoid, supravesical hernias and herniation through the foramen of Winslow. Because internal abdominal herniations are rare, their diagnosis remains a challenge for both the clinician and the radiologist. Symptoms of internal abdominal herniations are nonspecific. We present our experience with the radiological evaluation of internal abdominal herniations and review the main radiologic findings on barium as well as computed tomography studies.  相似文献   
72.
Objective: To evaluate the diagnostic value of screening laboratory tests in women who had recurrent pregnancy loss (RPL).

Methods: A total of 252 women with RPL managed in our tertiary referral research and education hospital were included in the study. Risk factors recorded involved age, gravidity, parity, number of prior live births, number of pregnancy losses, and thrombophlia tests. The cases were divided into three different groups and each group was analyzed separately.

Results: There was no statistically significant difference between the first and second groups in terms of clinical and laboratory parameters (p?>?0.05). In the third group, there was a statistically significant difference among cases in terms of parity, gravidity, number of pregnancy losses, serum AT III levels, APCR, and age of the women. According to the logistic regression model, odds ratios (95% CI) were 6.116 (3.797–9.852), 5.665 (2.657–12.079), 4.763 (3.099–7.321), 4.729 (3.080–7.260), 2.820 (1.836–4.333), and 1.911 (1.232–2.965), respectively.

Conclusions: We do not recommend the screening of all women with RPL, but in women with high parity and those who had prior live birth pregnancies, increased AT III, and APCR may be diagnostic markers for subsequent pregnancy loss.  相似文献   

73.
Objective: To evaluate the utility of cervical elastosonography (ES) in prediction of cervical insufficiency (CI).

Methods: A total of 40 women, of which 20 who had previously received the diagnosis of CI and 20 healty women were included in the study. None of the women were pregnant. All subjects underwent sonographic evaluation including cervical length measurement and ES of uterine cervix. Adjacent muscular tissue was the reference point for elastosonography evaluation. Tissue strain ratio values were obtained from all the patients.

Results: The area around the internal cervical os of the group with CI was found to be significantly softer as compared to the control group (higher SR rate, p?<?0.05). Furthermore, the outer parts of the cervix (sites A and D) were also found harder in the group that had CI (lower SR rate, p?<?0.05).

Conclusions: According to our knowledge, this is preliminary study to evaluate the predictive value of cervical ES in CI and we concluded that ES can be used as reliable method to determine CI but it is necessary to be studied in different cohort groups.  相似文献   

74.
The properties of melting are required for the prediction of solubility of solid compounds. Unfortunately, direct determination of the enthalpy of fusion and melting temperature by using conventional DSC or adiabatic calorimetry is often not possible for biological compounds due to decomposition during the measurement. To overcome this, fast scanning calorimetry (FSC) with scanning rates up to 2 × 104 K s−1 was used in this work to measure the melting parameters for l-alanine and glycine. The enthalpy of fusion and melting temperature (extrapolated to zero heating rate) were ΔfusH = (22 ± 5) kJ mol−1 and Tfus = (608 ± 9) K for l-alanine, and ΔfusH = (21 ± 4) kJ mol−1 and Tfus = (569 ± 7) K for glycine. These melting properties were used in the modeling framework PC-SAFT to predict amino-acid solubility in water. The pure-component PC-SAFT parameters and one binary parameter were taken from literature, in which these parameters were fitted to solubility-independent thermodynamic properties such as osmotic coefficients or mixture densities. It was shown that this allowed accurately predicting amino-acid solubility in water over a broad temperature range. The combined methodology of PC-SAFT and FSC proposed in this work opens the door for predicting solubility of molecules that decompose before melting.

New experimental melting properties combined with PC-SAFT allow quantitative solubility predictions of amino acids in water.  相似文献   
75.
Stretchable gas sensors are important components of wearable electronic devices used for human safety and healthcare applications. However, the current low stretchability and poor stability of the materials limit their use. Here, we report a highly stretchable, stable, and sensitive NO2 gas sensor composed of reduced graphene oxide (RGO) sheets and highly elastic commercial yarns. To achieve high stretchability and good stability, the RGO sensors were fabricated using a pre-strain strategy (strain-release assembly). The fabricated stretchable RGO gas sensors showed high NO2 sensitivity (55% at 5.0 ppm) under 200% strain and outstanding mechanical stability (even up to 5000 cycles at 400% applied strain), making them ideal for wearable electronic applications. In addition, our elastic graphene gas sensors can also be woven into fabrics and clothes for the creation of smart textiles. Finally, we successfully fabricated wearable gas-sensing wrist-bands from superelastic graphene yarns and stretchable knits to demonstrate a wearable electronic device.

Highly stretchable, mechanically stable and weavable RGO elastic electronic yarns were developed using dip-coating with pre-straining. We demonstrate wearable gas sensors that can be worn on the wrist.  相似文献   
76.
77.
Viral hepatitis infection is a major global issue and a leading cause of liver disease and associated deaths. Over time, patients infected with hepatitis B (HBV) or C virus (HCV) develop cirrhosis and, eventually, hepatocellular carcinoma (HCC). For this reason, they need to be constantly monitored. Current Asian guidelines recommend the determination of serum alpha-fetoprotein (AFP) together with liver ultrasounds every six months to detect HCC nodules. However, both methods have several limitations, and other biomarkers have been studied for monitoring cirrhosis, including SCCA-IgM, an immune-complex formed by Squamous Cell Carcinoma Antigen and IgM. To date, SCCA-IgM has been validated as a novel biomarker for liver diseases only in European populations. The aim of our study was to analyze SCCA-IgM as a biomarker to monitor cirrhosis evolution in an Asian cohort of patients and to compare its performance to that of AFP. We analyzed the concentration of AFP and SCCA-IgM in serum samples obtained from a group of Asian adult patients with cirrhosis or HCC and a control group of patients admitted for gastrointestinal disorders. In untreated patients and similarly to AFP, SCCA-IgM levels were significantly higher in patients with cirrhosis compared to those with HCC. In addition, SCCA-IgM, but not AFP serological levels, were significantly lower in HCC patients who were treated with surgical resection compared to those who received a different therapy.  相似文献   
78.
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   
79.
Pre-cut papillotomy with a new papillotome   总被引:4,自引:0,他引:4  
BACKGROUND: A new papillotome has been developed, an isolated-tip needle-knife papillotome (Iso-Tome) that has a semi-oval-shaped tip of epoxide adhesive to prevent electric leakage from the tip of the incising needle. The coated tip aids in keeping the papillotome tightly in the orifice of the ampulla of Vater and is believed to prevent unintentional deep cuts or perforations. This study was done to evaluate the clinical usefulness of the new papillotome for pre-cut papillotomy. METHODS: From June 2003 to November 2003, 115 patients underwent attempted ERCP. If biliary cannulation failed by the conventional method, pre-cut papillotomy was performed by using the Iso-Tome in the direction of the bile duct. After successful bile-duct cannulation, papillotomy was extended for therapeutic procedures, such as stone removal or stent insertion, in the majority of the cases. Post-ERCP complications were classified according to consensus guidelines. OBSERVATIONS: Pre-cut papillotomy with the Iso-Tome was done in 25 patients (21.7% of cases). Protective pancreatic stents were not used. Of these patients, 11 had common bile duct stones, 7 had pancreatitis, 5 had malignancies, one had sphincter of Oddi dysfunction, and one had bile-duct leak. After pre-cut papillotomy with the Iso-Tome, bile-duct cannulation was successfully achieved in 23 of 25 (92%) patients. Complications occurred in 7 of 25 patients (28%) and consisted of mild pancreatitis in 5 (20%), moderate bleeding in one (4%), and biliary pain in one (4%). All 7 patients with complications were managed medically, and there was no death. CONCLUSIONS: In this pilot study, the isolated-tip needle knife was found to be a clinically useful papillotome for pre-cut papillotomy. Further large comparative studies (with and without pancreatic protective stents) are needed to determine improved efficacy and safety compared with standard techniques.  相似文献   
80.
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   
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