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91.
92.
The behavior at degradation by soil burial of some plasticized polyvinyl chloride (PVC) based blends with a variable content of hydrolyzed collagen (HC) has been followed. MATERIAL AND METHOD: The modifications induced in the environment by the polymer systems (pH variation, physiologic state of the plants, assimilatory pigments) were studied. Using the growth test of the terrestrial plants, we followed the development of Triticum (wheat), Helianthus annus minimus (little sunflower), Pisum sativum (pea), and Vicia X hybrida hort, during a vegetation cycle. After the harvest, for each plant, the quantities of chlorophyll and carotenoidic pigments and of trace- and macroelements were determined. RESULTS: It was proved that, in the presence of polymer blends, the plants do not suffer morphological and physiological modifications, the products released in the culture soil being not toxic for the plants growth.  相似文献   
93.

Purpose

The success rate for infraclavicular brachial plexus block using nerve stimulation reportedly ranges from 60 to 80%. Ultrasound guidance may be associated with greater success. This study compared ultrasound guided infraclavicular block with a dual motor endpoint nerve stimulation technique.

Methods

One hundred three hand surgery patients were randomized to receive either ultrasound-guided (ultrasound group) or dual motor endpoint nerve stimulation (stimulation group) infraclavicular block using 2% lidocaine 15 mL and 0.5% bupivacaine 15 mL with epinephrine. Block success was defined as loss of sensation to pinprick in each of the radial, ulnar, median, and musculocutaneous nerve distributions when measured 20 min after block performance. Block performance time, readiness for surgery (no supplemental block, skin infiltration, or general anesthesia), and complications were also assessed.

Results

Patient characteristics were similar between groups. Success rate was 92% in the ultrasound group and 80% in the stimulation group (P = 0.18). Block performance time was shorter in the ultrasound group (median 5 min) compared with the stimulation group (median 10.5 min) (P < 0.001). Paresthesiae were more frequent in the stimulation group (45%) than in the ultrasound group (6%) (P < 0.001). After final injection, more patients were ready for surgery in the ultrasound group (85%) than in the stimulation group (65%) (P = 0.04). At 1 week postoperatively, complications were minor and transient and did not differ between groups.

Conclusion

There was no statistically significant difference in the success rate between ultrasound guidance and dual motor endpoint stimulation for infraclavicular block. However, ultrasound guidance shortens performance time and improves readiness for surgery compared with dual motor endpoint stimulation (Clinical Trial Registration Number: NCT00326261).  相似文献   
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Neuropathy with antibodies against myelin-associated glycoproteins (MAG/SGPG-N) and hereditary sensorimotor neuropathy type 1 (HMSN1) are characterized by chronic demyelination with little conduction block. Electrodiagnostic studies suggest that in HMSN1 conduction slowing occurs uniformly along the nerve, whereas in MAG/SGPG-N it is predominantly distal. Some but not all previous reports have shown that the terminal latency index (TLI) was useful to distinguish MAG/SGPG-N from chronic idiopathic demyelinating polyneuropathy. We compared median TLI from 21 patients with MAG/SGPG-N with those obtained from 26 patients with HMSN1, 20 with HMSN2, and 12 healthy volunteers. All patients with TLI <0.26 had MAG/SGPG-N, and all patients with TLI > or =0.32 had HMSN1. In the remaining patients with intermediate TLI values, ulnar distal motor latency (DML) aided in differentiation between MAG/SGPG-N and HMSN1 with an overall sensitivity of 100% and specificity of 98%. In conclusion, median TLI in combination with ulnar DML can further guide the demyelinating neuropathy evaluation toward hereditary or autoimmune causes.  相似文献   
96.

Background

Elevations in cardiac troponin have prognostic importance in critically ill patients. However, there are no data addressing the independent association between troponin levels and mortality, adjusted for the severity of the underlying disease, in patients hospitalized for acute respiratory disorders. We investigated whether troponin T (cTnT) elevations are independently associated with in-hospital mortality in patients in the intensive care unit (ICU) admitted for severe and acute respiratory conditions. After adjusting for the severity of disease measured by the Acute Physiology, Age, and Chronic Health Evaluation (APACHE) III prognostic system, we evaluated short-term (30 days) and long-term (3 years) mortality.

Methods

We studied the APACHE III database and cTnT levels from patients admitted consecutively to the ICU at Mayo Clinic, Rochester, Minnesota. Between January 2001 and December 2005, 2078 patients with respiratory conditions had cTnT measured at ICU admission. In-hospital, short-term (30 days) and long-term (3 years) all-cause mortality were determined.

Results

Of the study patients, 878 (42.3%) had elevated cTnT and 1200 patients (57.7%) had undetectable cTnT. During hospitalization, 1.1% of the patients with troponin T <0.01 ng/mL died compared to 21% of those with troponin T ≥0.01 ng/mL (P <.0001). At 30 days, mortality was 18.6% in patients with elevations of cTnT and 1.5% in patients without elevations of cTnT (P <.0001). The Kaplan-Meier probability of survival at 1-year follow-up was 71.0%, at 2-year follow-up was 48.3%, and 3-year follow-up was 39.4% with troponin T ≥0.01 ng/mL and at 1-year follow-up was 98.8%, at 2-year follow-up was 97.2%, and at 3-year follow-up was 95.5% with troponin T <0.01 μg/L (P <.0001). After adjustment for severity of disease and baseline characteristics, cTnT levels remained associated with in-hospital, short-term and long-term mortality (P <.0001).

Conclusions

In patients admitted to the ICU for respiratory disorders, cTnT elevations are independently associated with in-hospital, short-term and long-term mortality.  相似文献   
97.
98.
99.
According to the International Commission on Trichinellosis survey in 2004, Romania has the most cases of trichinellosis in the world. Epidemiologic data for each county were collected and analyzed from two different time periods: before (1980-1989) and after (1990-2004) political changes. Data were analyzed separately for Transylvania and the rest of the Romanian counties. During the past 25 years, 28,293 human cases of trichinellosis were reported with an incidence of 51.0 cases per 10(6) persons per year. An important increase in the incidence was observed from 1980 to 1989 compared with the 1990-2004 period. For the entire period, the incidence rate obtained for Transylvanian counties (82.2 cases per 10(6) persons per year) was higher than the incidence rate obtained for the other counties (35.7 cases per 10(6) persons per year). Hypotheses and facts contributing to the heterogeneity of human trichinellosis cases are discussed.  相似文献   
100.
Although neither kinase-dead human epidermal growth factor receptor (HER)3 nor orphan HER2 can be activated by HER-related ligands on their own, the formation of HER2/HER3 heterodimers creates the most mitogenic and transforming receptor complex within the HER (erbB) family of transmembrane receptor tyrosine kinases. The incorporation of markers such as HER3 transactivation, HER2/HER3 dimer, or others that may provide information regarding the level of HER pathway engagement has been demonstrated to allow identification of patients who respond to or escape HER-targeted therapies. Pioneering studies showed that high expression of kinase-dead HER3 can predict early escape from the anti-HER2 monoclonal antibody trastuzumab. Also, the growth-inhibitory effects of HER1/2 tyrosine kinase inhibitors (TKIs) were previously found to be attenuated in the presence of heregulin, which is a high-affinity combinatorial ligand for HER3. All of these concepts are being revisited with respect to the efficacy of HER family TKI therapies; in particular, HER3 signalling buffered against incomplete inhibition of HER2 kinase activity has been suggested to be the mechanism that allows HER2 over-expressing breast cancer cells to escape HER TKIs. It remains to be elucidated whether reactivation of HER3 signalling can also account for the poor efficacy of HER TKIs in treating breast carcinomas that contain low overall levels of HER2 receptors. However, it appears that regardless of the mechanism that triggers the formation of oncogenic HER2/HER3 heterodimers (HER2 over-expression or overall low HER2 but high levels of the HER3 ligand heregulin), HER3 transphosphorylation is a common response of breast cancer cells upon treatment with current inhibitors of the HER receptor tyrosine kinase network. Because kinase-inactive HER3 is not presently an amenable target for forthcoming HER TKIs, molecular approaches that can efficiently block heregulin-triggered HER3 transactivation or nucleocytoplasmic trafficking of heregulin might offer novel strategies with which to manage HER-driven breast cancer disease.  相似文献   
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