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11.
Deltamethrin, a synthetic pyrethroid pesticide contaminating aquatic ecosystems as a potential toxic pollutant, was investigated in the present study for acute toxicity. Guppy fish (Poecilia reticulata) were selected for the bioassay experiments. The 48-h LC50 was determined for the guppies. The experiments were repeated three times and a total of 210 guppies were used. The static test method of acute toxicity test was used. In addition, behavioral changes at each deltamethrin concentration were determined for the individuals. Data obtained from the deltamethrin acute toxicity tests were evaluated using the Probit Analysis Statistical Method. The 48-h LC50 value for guppy was estimated as 5.13 microg/L.  相似文献   
12.
Pinar R 《Cancer nursing》2004,27(3):252-257
This study examined the reliability and validity of the Turkish version of the Multidimensional Quality of Life Scale - Cancer Version 2 (MQOLS-CA2) in 72 people with cancer. The results indicated that the MQOLS-CA2 has good construct validity. Factor analysis confirmed the presence of 5 factors in the MQOLS-CA2: psychological well-being, physical well-being, nutrition, symptom distress, and interpersonal well-being. The correlation between the global scores of the MQOLS-CA2 and Medical Outcomes Study 36-Item Short Form Health Survey was significant (r = 0.78, P =.0001), supporting the criterion validity of the MQOLS-CA2. Results of the test-retest method showed that stability coefficients for the 5 subscales of the MQOLS-CA2 ranged from 0.56 (symptom distress) to 0.91 (general physical well-being). Cronbach alpha coefficients surpassed the 0.70 criterion for all subscales, indicating good internal consistency. The acceptability rate was excellent at 96% completed questionnaires. In conclusion, the findings suggest that the Turkish version of the MQOLS-CA2 is a valid and reliable instrument that can be used in cancer research.  相似文献   
13.
AIM: In developed countries, there has been a recent increase in the prevalence of adenocarcinoma of the esophagus and cardia, along with a decrease in distal gastric cancers. Little is known regarding the prevalence of these diseases in developing countries. The aim of the present study was to evaluate changes in the prevalence of gastric adenocarcinomas in Turkey as a function of anatomic location. METHODS: Data were retrospectively collected from 16 centers from January 1990 to December 2000. Owing to the exclusion criteria, a total of 4065 cases of tumors of the stomach and distal esophagus were included. Tumors localized to the body, the antrum and pyloric channel were considered distal cancers. Helicobacter pylori (H. pylori) was also detected. RESULTS: Patients' mean age was 60.7 +/- 9 years, with a male : female ratio of 68:32. The ratio of distal/proximal adenocarcinoma was 2:1 for the western part of Turkey and 3:8 for the eastern part of the country (P < 0.0001), and this did not change during the 11 years. H. pylori was detected significantly less in the west compared to the east for distal tumors (65.7 vs 38.7%, respectively, P = 0.02). CONCLUSION: In Turkey, a developing country with a high H. pylori prevalence, contrary to the state of developed countries, the ratio of distal versus proximal gastric adenocarcinomas has not changed. Geographical distribution should be taken into the account in projecting the changing patterns of gastric cancers.  相似文献   
14.
Dietary lipids and lipophilic vitamins are transported by postprandial lipoproteins and are required for bone metabolism. Despite that, it remains unknown whether bone cells are involved in the uptake of circulating postprandial lipoproteins in vivo. The current study was performed to investigate a putative participation of bone in the systemic postprandial lipoprotein metabolism in mice, to identify potentially involved cell type populations and to analyze whether lipoprotein uptake affects bone function in vivo. As a model for the postprandial state, chylomicron remnants (CR) were injected intravenously into mice. Next to the liver and compared to other organs, bone appeared to be the second most important organ for the clearance of radiolabeled CR particles from the circulation in vivo. In addition, uptake of radiolabeled CR by primary murine osteoblasts and hepatocytes was quantified to be in a similar range in vitro. A complementary approach with fluorescently labeled CR and immunohistochemical staining for apoE proved that intact CR particles were taken up into bone and liver. Electron microscopy localization studies of bone sections revealed CR uptake into sinusoidal endothelial cells, macrophages and osteoblasts. The relative amount of radiolabeled CR uptake into femoral cortical bone, representing predominantly osteoblasts, and bone marrow, representing predominantly non-osteoblast cells, was within the same range. Most importantly, the injection of vitamin K1-enriched CR resulted in an increase of the degree of osteocalcin carboxylation in vivo while total osteocalcin concentrations remained unaffected, giving functional proof that osteoblasts process CR in vivo. In conclusion, here we demonstrate that bone is involved in the postprandial lipoprotein metabolism in mice. Osteoblasts participate in CR clearance from the circulation, which has a direct impact on the secretory function of osteoblasts.  相似文献   
15.
Anetoderma, is characterized by herniated atrophic macules clinically and by decreased to absent dermal elastic fibers histopathologically. Atrophoderma is characterized by depressed, atrophic, pigmented patches clinically and by thickened and homogenized dermal collagen bundles with absence of elastolysis histopathologically. Atrophoderma elastolyticum discretum describes lesions that are reminiscent of atrophoderma clinically but they are compatible with anetoderma histopathologically. A 34-year-old female patient presented with diffuse, hypopigmented, atrophic, shiny macules on the upper limbs and upper trunk. Histopathological examination revealed an atrophic epidermis with disorganized, hyalinized and coarse collagen bundles in the middle and lower dermis. Elastic fiber loss and fragmentation were detected in the upper dermis. The other patient was a 42-year-old female patient. She applied with diffuse, hypopigmented, shiny, atrophic macules on the upper limbs and upper trunk. Histopathological examination revealed findings that were similar to those of the first case but there was near complete loss of elastic fibers throughout the whole thickness of dermis. Our cases did not show depressed or herniated atrophic macules clinically but the macules were at the same level with the surrounding healthy skin. Histopathological findings in these cases showed the histopathological features of both atrophoderma and anetoderma. These two cases are interesting because they may represent a clinicopathological entity which has not been described before.  相似文献   
16.
We discuss MRI findings in patients with thoracic outlet syndrome (TOS). A total of 100 neurovascular bundles were evaluated in the interscalene triangle (IS), costoclavicular (CC), and retropectoralis minor (RPM) spaces. To exclude neurogenic abnormality, MRIs of the cervical spine and brachial plexus (BPL) were obtained in neutral. To exclude compression on neurovascular bundles, sagittal T1W images were obtained vertical to the longitudinal axis of BPL from spinal cord to the medial part of the humerus, in abduction and neutral. To exclude vascular TOS, MR angiography (MRA) and venography (MRV) of the subclavian artery (SA) and vein (SV) in abduction were obtained. If there is compression on the vessels, MRA and MRV of the subclavian vessels were repeated in neutral. Seventy-one neurovascular bundles were found to be abnormal: 16 arterial-venous-neurogenic, 20 neurogenic, 1 arterial, 15 venous, 8 arterial-venous, 3 arterial-neurogenic, and 8 venous-neurogenic TOS. Overall, neurogenic TOS was noted in 69%, venous TOS in 66%, and arterial TOS in 39%. The neurovascular bundle was most commonly compressed in the CC, mostly secondary to position, and very rarely compressed in the RPM. The cause of TOS was congenital bone variations in 36%, congenital fibromuscular anomalies in 11%, and position in 53%. In 5%, there was unilateral brachial plexitis in addition to compression of the neurovascular bundle. Severe cervical spondylosis was noted in 14%, contributing to TOS symptoms. For evaluation of patients with TOS, visualization of the brachial plexus and cervical spine and dynamic evaluation of neurovascular bundles in the cervicothoracobrachial region are mandatory.  相似文献   
17.
Renal cell carcinoma (RCC) has a high metastatic potential due to its hematogen and vascular features. It metastasizes frequently to the lungs, the bones, the liver, the lymph nodes and the brain. Metastasis of RCC to the head and neck region is quite rare. In this case report, two RCC patients with head and neck metastases are presented: one occurring after 5 years and the other occurring 17 years after diagnosis.  相似文献   
18.
Rho kinase has contractile activity, which induces Ca2+ sensitization in various cells. Several receptors are linked to the Rho/Rho-kinase pathway. Therefore, in this study we aimed to demonstrate the central importance of this novel pathway for diverse excitatory stimuli in the smooth muscle of the sheep gallbladder. Accordingly, the effects of a Rho kinase inhibitor, (+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride monohydrate (Y-27632, 10(-8)-3 x 10(-5) M), were investigated on cholecystokinin-8 (CCK-8, 10(-8) M), endothelin-1 (10(-8) M), carbachol (10(-6)-10(-5) M), 5-hydroxytryptamine (5-HT, 10(-6)-10(-5) M), histamine (10(-6)-10(-5) M), phenylephrine (10(-5)-10(-4) M), neurokinin A (10(-7)-10(-6) M), electrical field stimulation (40 V, 0.5 ms, 2, 4, 8, 16, 32 Hz, 15 s, 3 min intervals) and potassium chloride (KCl, 25-50 mM)-induced contractions as well as spontaneous contractile activity. Electrical field stimulation evoked tetrodotoxin (3 x 10(-6) M)-sensitive reproducible contractions, which were inhibited by atropine (2 x 10(-6) M) and potentiated by eserine (5 x 10(-7) M). EFS-induced contraction was significantly inhibited by Y-27632 (10(-5) M). In addition, spontaneous contractile activity was suppressed in the presence of the compound (10(-6)-10(-5) M). This Rho kinase inhibitor also dramatically decreased the contractions elicited by 5-HT, neurokinin A and carbachol. KCl-induced contraction, which was not atropine-sensitive, was also conspicuously attenuated by Y-27632. Moreover, Y-27632 (10(-8)-3 x 10(-5) M) relaxed gallbladder strips that were contracted by histamine, endothelin-1, CCK-8 and phenylephrine in a concentration-dependent manner. pEC50 values for Y-27632 were 6.25+/-0.10, 5.79+/-0.12, 5.83+/-0.09 and 5.70+/-0.13 for the contraction elicited by histamine, CCK-8, endothelin-1 and phenylephrine, respectively. Furthermore, we also demonstrated Rho kinase protein expression (ROCK-1 and ROCK-2) by Western blot analysis. In conclusion, ROCK is expressed in the smooth muscle of the ovine gallbladder, and it has a central role in the contractile activity induced by diverse excitatory stimuli.  相似文献   
19.

Background

Although several studies have described effects of dexmedetomidine on peripheral nerve blocks, to date there is limited knowledge available on the impact of dexmedetomidine adjunct to levobupivacaine in axillary brachial plexus block.

Objective

In this study, we aimed to investigate the effects of adding dexmedetomidine to levobupivacaine for an axillary brachial plexus block.

Methods

A total of 64 patients of American Society of Anesthesiologists physical status I/II scheduled to undergo forearm and hand surgery, in which an axillary block was used, were enrolled. The patients were randomly divided into 2 groups: in group L patients (n = 32), an axillary block was performed with 39 mL levobupivacaine 5% plus 1 mL of isotonic sodium chloride. In group D patients (n = 32), an axillary block was performed with 39 mL levobupivacaine 5% and 1 mL dexmedetomidine 1 μg/kg−1 plus isotonic sodium chloride. Demographic data, mean arterial pressure (MAP), heart rate (HR), peripheral oxygen saturation (Spo2), sensory and motor block onset times and block durations, time to first analgesic use, total analgesic need, intraoperative verbal analog scale, postoperative visual analog scale (VAS) data, and side effects were recorded for each patient.

Results

There were no significant differences in patient and surgery characteristics between the 2 groups. Sensory block onset time was shorter in group D (P < 0.05). Sensory and motor block duration and time to first analgesic use were significantly longer in group D (P < 0.05), and the total need for analgesics was lower in group D (P < 0.05). Intraoperative 5- and 10-minute verbal analog scale values and postoperative VAS value at 12 hours were significantly lower in group D (P < 0.05). Intraoperative MAP and HR values, except at 5 minutes and postoperatively at 10 and 30 minutes and 1 and 2 hours, were significantly lower in group D (P < 0.01). Bradycardia, hypotension, hypoxemia, nausea, vomiting, and any other side effects were not seen in any patients.

Conclusions

It was concluded in our study that adding dexmedetomidine to axillary brachial plexus block shortens sensory block onset time, increases the sensory and motor block duration and time to first analgesic use, and decreases total analgesic use with no side effects. ClinicalTrials.gov identifier ISRCTN67622282.Key Words: axillary brachial plexus block, dexmedetomidine, levobupivacaine  相似文献   
20.
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