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991.
The purpose of this article is to describe a nursing experience with a patient with esophagus cancer combined with tumor ulcer. The author assessed the patient's health condition by observation, interview, medical history and the Gorden functional health assessment guide. The client had three nursing problems: impaired tissue integrity, diarrhea and body image disturbance. The author used the nursing process and empathy to assist the patient to face disease and treatment. Nursing intervention was also performed to enhance the patient's comfort and provide psychological support.  相似文献   
992.
AIM: To investigate the correlation between tissue ST6Gal Ⅰ and serum msAFP in HCC patients, and to investigate their prognostic significance. METHODS: Preoperative sera, paired tumorous and non-tumorous tissues were collected from 19 consecutive patients who had undergone surgical resection of HCC. ST6Gal Ⅰ activities in the tissues were measured by an in vitro microsomal enzyme activity assay. The percentages of tumor-specific msAFP in the sera were also estimated by an isoelectric focusing-immunoblotting assay. RESULTS: The tumor ST6Gal Ⅰ activity was negatively correlated with serum msAFP percentage (r = -0.53, P = 0.019). Both decreased tumor ST6Gal Ⅰ activity and increased serum msAFP percentage were associated with poor tumor cell differentiation. Univariate analyses showed that both decreased tumor ST6Gal Ⅰ activity (P = 0.028), increased serum msAFP percentage (P = 0.034) and poor tumor cell differentiation (P = 0.031) were associated with shorter overall survival. Multivariate analysis using the Cox regression model showed that the preoperative serum msAFP percentage (P = 0.022) and tumor cell differentiation status (P = 0.048) were independent prognostic indicators for patient overall survival. CONCLUSION: Our results indicate that the presence of msAFP in blood circulation is associated with a decreased activity of ST6Gal Ⅰ activity in HCC. Both tissue ST6Gal Ⅰ and serum msAFP are potential prognostic markers for patients with operable HCC.  相似文献   
993.
The present study was undertaken to examine the effects of prolonged in vivo treatment with T3 and long acting thyroid stimulator (LATS) on in vitro responsiveness of mouse thyroid cyclic AMP to thyrotrophin (TSH) and LATS-immunoglobulin G (IgG). In control mice, thyroid cAMP concentrations after incubation with normal-IgG (10 mg/ml) for 2 h, TSH (10 mU/ml) for 10 min and LATS-IgG (10 mg/ml) for 2 h were 1.25 +/- 0.11 (mean +/- SE) (n = 5), 15.87 +/- 3.47 (n = 6) and 2.17 +/- 0.25 pmoles/mg wet weight (n = 6), respectively. In mice given T3 (5 micrograms/ml) in drinking water for 5 days, thyroid cAMP concentrations after an incubation with TSH were reduced by 50%, as compared to those of the control mice. They were also decreased in mice injected ip with 5 mg of LATS-IgG (1000%/5 mg in the McKenzie bioassay) daily for 5 days. Combined treatment with T3 and LATS decreased the cAMP response to TSH only to the same extent as did T3 alone, indicating that the inhibitory effects of T3 and LATS were not additive. Similar findings were observed with the thyroid cAMP response to LATS-IgG in vitro; either T3 or LATS treatment in vivo decreased cAMP response to LATS-IgG in vitro, but combined treatment with T3 and LATS did not cause further inhibition as compared with T3 or LATS treatment alone.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.

Background

Fibromyalgia is a syndrome of chronic pain and other symptoms and is associated with patient discomfort and other diseases. This nationwide matched-cohort population-based study aimed to investigate the association between fibromyalgia and the risk of developing dementia, and to clarify the association between fibromyalgia and dementia.

Materials and Methods

A total of 41,612 patients of age ≥50 years with newly diagnosed fibromyalgia between January 1, and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 124,836 controls matched for sex and age. After adjusting for any confounding factors, Fine and Gray competing risk analysis was used to compare the risk of developing dementia during the 10 years of follow-up.

Results

Of the study subjects, 1,704 from 41,612 fibromyalgia patients (21.23 per 1,000 person-years) developed dementia when compared to 4,419 from 124,836 controls (18.94 per 1,000 person-years). Fine and Gray competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio: 2.29, 95% CI: 2.16-2.42; P < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region of residence and comorbidities the hazard ratio was 2.77 (95% CI: 2.61-2.95, P < 0.001). Fibromyalgia was associated with increased risk of all types of dementia in this study.

Conclusions

The study subjects with fibromyalgia had a 2.77-fold risk of dementia in comparison to the control group. Therefore, further studies are needed to elucidate the underlying mechanisms of the association between fibromyalgia and the risk of dementia.  相似文献   
995.
PURPOSE: A somatoanal reflex had been demonstrated in our previous work. Because nitric oxide plays an important role in mediating relaxation of the internal anal sphincter, our purpose was to examine whether and how local somatothermal stimulation inhibits the function of the internal anal sphincter by stimulating nitric oxide releasevia nitrergic neurons and to elucidate the possible mechanism. METHODS: The activity of the internal anal sphincter in anesthetized rabbits was measured by use of continuously perfused, open-tip manometric methods. Local somatothermal stimulation was achieved by applying an electroheating rod 1 cm away from the skin area at the right popliteal region. The responses were further manipulated by pretreating the rabbits with agonists or antagonists linked to nitric oxide synthesis. RESULTS: The motility of the internal anal sphincter before and during local somatothermal stimulation was significantly different (tonic pressure (mean ± standard error of the mean), 5.4 ± 0.3vs. 4.9 ± 0.3 mmHg,P=0.0195; phasic pressure, 3.9 ± 0.6vs. 2.9 ± 0.4 mmHg,P=0.0002; frequency distribution of the phasic contractions (peak-to-peak interval), 28.9 ± 3.7vs. 65.3 ± 10.4 seconds,P=0.0001). The response began at approximately one minute after local somatothermal stimulation when the skin temperature was 41 ± 0.3°C. No anal response was observed when local somatothermal stimulation was applied at the control area. The local somatothermal stimulation-induced internal anal sphincter relaxation was not inhibited by pretreatment with atropine, propranolol, or phentolamine (tonic pressure, 5.8 ± 1vs. 5.2 ± 0.8 mmHg,P=0.038; phasic pressure, 4.2 ± 0.9vs. 3.1 ± 0.6 mmHg,P=0.020; peak-to-peak interval, 27.2 ± 4.3vs. 52.9 ± 14.5 seconds,P=0.043) but was completely blocked by pretreatment with a nitric oxide synthesis inhibitor. The effect of the nitric oxide synthesis inhibitor could be reversed by pretreatment with L-arginine (tonic pressure, 6 ± 0.7vs. 5.6 ± 0.7 mmHg,P=0.047; phasic pressure, 4.7 ± 0.7vs. 3.9 ± 0.5 mmHg,P=0.048; peak-to-peak interval, 23.8 ± 3vs. 33 ± 3.7 seconds,P=0.048), but not by D-arginine. CONCUSION: Local somatothermal stimulation inhibits internal anal sphincter motility through the activation of nonadrenergic noncholinergic neural release of nitric oxide. This procedure may represent a simplified approach for the treatment of anorectal diseases with hypofunction of the L-arginine/nitric oxide pathway.Presented at the XVIIth Biennial Congress of the International Society of University Colon and Rectal Surgeons, Malmö, Sweden, June 7 to 11, 1998.  相似文献   
996.
Verapamil is a widely used Ca(2+) channel antagonist in the treatment of cardiovascular disorders including atrial arrhythmias. However, it is unknown whether the drug would inhibit the repolarization currents transient outward K(+) current (I(to1)) and ultra-rapid delayed rectifier K(+) current (I(Kur)) in human atrium. With whole-cell patch configuration, we evaluated effects of verapamil on I(to1) and I(Kur) in isolated human atrial myocytes. It was found that verapamil did not decrease I(to1) at 1-50 microM. However, verapamil reversibly inhibited I(Kur) in a concentration-dependent manner (IC(50) = 3.2 microM). At test potential of +50 mV, 5 microM verapamil decreased I(Kur) by 61.3 +/- 7.5%. Verapamil significantly accelerated inactivation of I(Kur), suggesting an open channel block mechanism. The results indicate that verapamil significantly blocks the repolarization K(+) current I(Kur), but not I(to1), in human atrial atrium, which may account at least in part for the atrial effect of the drug.  相似文献   
997.
A series of cubic network phases was obtained from the self-assembly of a single-composition lamellae (L)-forming block copolymer (BCP) polystyrene-block-polydimethylsiloxane (PS-b-PDMS) through solution casting using a PS-selective solvent. An unusual network phase in diblock copolymers, double-primitive phase (DP) with space group of Im3¯m, can be observed. With the reduction of solvent evaporation rate for solution casting, a double-diamond phase (DD) with space group of Pn3¯m can be formed. By taking advantage of thermal annealing, order–order transitions from the DP and DD phases to a double-gyroid phase (DG) with space group of Ia3¯d can be identified. The order–order transitions from DP (hexapod network) to DD (tetrapod network), and finally to DG (trigonal planar network) are attributed to the reduction of the degree of packing frustration within the junction (node), different from the predicted Bonnet transformation from DD to DG, and finally to DP based on enthalpic consideration only. This discovery suggests a new methodology to acquire various network phases from a simple diblock system by kinetically controlling self-assembling process.

From constituted molecules to polymers, finally ordered hierarchical superstructures, self-assembled solids cover a vast area of nanostructures where the characters of building blocks direct the progress of self-assembly (1, 2). In nature, fascinating periodic network structures and morphologies from different species are appealing in nanoscience and nanotechnology due to their superior properties, especially for photonic crystal structures (37). For gyroid, trigonal planar network with chirality demonstrates its potential as chiropitc metamaterial (810). Beyond the splendid colors, networks either in macroscale or mesoscale mechanically strengthen their skeletons and protect those fragile but vital organs from impact (11, 12). Inspired by nature, biomimicking materials with mesoscale network may exceed the limitation of the intrinsic properties (13). The topology of networks could further improve their adaptability, allowing extreme deformation for energy dissipation (14). Moreover, network materials from hybridization of self-assembled block copolymers (BCPs) have been exploited to the design of mesoscale quantum metamaterials (15, 16). With the desire to acquire network textures for biomimicking nanomaterials, BCPs with immiscible constituted segments covalently joined together give the accessibility to the formation of nanonetwork morphologies via balancing enthalpic penalty from the repulsive interaction of constituted blocks and entropic penalty from the stretching of polymer chains (1721). By taking advantage of precise synthesis procedures, it is feasible to obtain the aimed network phases from the self-assembly of BCPs such as Fddd (O70) (2224), gyroid (Q214, Q230) (20, 21, 2527), and diamond (Q224, Q227) (2831) experimentally and theoretically. On the basis of theoretical prediction, the junction points (nodes) in the network phases could be coordinated with three, four, or six neighbors in three-dimensional space, resulting in the enhancement of packing frustration (31). Topologically, all these phases match the coordination number to neighbors (n = 3, 4, 6), showing no special case of quasicrystal. Accordingly, an order–order transition from double-diamond phase (DD, tetrapod) to double-gyroid phase (DG, trigonal planar network) has been observed (29). Yet, there is no DP phase being found in simple diblock systems except for liquid crystals (32, 33) or organic–inorganic nanocomposites from the mixtures of BCP with inorganic precursors (34, 35). Searching the rare occurrence of network phases and the corresponding phase transitions among phases will be essential to the demands for application by considering the deliberate structuring effects on aimed properties but the approaches remain challenging (8, 3640). For instance, viewing the narrow window for network morphologies in diblock copolymer phase diagram, it demands harsh requirements for syntheses (2, 41). Recently, by taking advantage of using selective solvent for solution casting, it is feasible to acquire DG phase and even inverted DG phase from the self-assembly of lamellae (L)-forming polystyrene-block-polydimethylsiloxane (PS-b-PDMS) (42). Apart from that, a triclinic DG phase was recently discovered from the PS-b-PDMS which is commonly believed nonexisting in the conventional phase diagram (43). As a result, the phase diagram of BCPs with high interaction parameter is worthy of study for searching the metastable phases with unique network textures (44). Herein, we aim to acquire network phases from a simple diblock system by kinetically controlling the transformation mechanisms of self-assembly. As exemplified by using the PS-b-PDMS for solution casting, with the use of a PS-selective solvent (chloroform), a DP phase and a DD phase could be formed through controlled self-assembly, giving unique network phases simply from solution casting. Moreover, a DG phase can be also acquired from phase transformation. Consequently, a series of network phases with hexapod, tetrapod, and trigonal planar building units could be successfully obtained by using a single-composition L-forming PS-b-PDMS for self-assembly. The corresponding order–order transitions among these network phases examined by temperature-resolved in situ small-angle X-ray scattering (SAXS) combining with electron tomography results provide insights of network phase formation and the corresponding phase transformation mechanisms in the self-assembly of BCPs.  相似文献   
998.
999.
Patients with cancer are at high risk for thrombotic events,which are known collectively as Trousseau's syndrome. Herein,we report a 66-year-old male patient who was diagnosed with terminal stage gastric cancer and liver metastasis and who had an initial clinical presentation of upper gastrointestinal bleeding. Acute ischemia of the left lower leg that resulted in gangrenous changes occurred during admission. Subsequent angiography of the left lower limb was then performed. This procedure revealed arterial thrombosis of the left common iliac artery with extension to the external iliac artery,the left common iliac artery,the posterior tibial artery,and the peroneal artery,which were occluded by thrombi. Aspiration of the thrombi demonstrated that these were not tumor thrombi. The interesting aspect of our case was that the disease it presented as arterial thrombotic events,which may correlate with gastric adenocarcinoma. In summary,we suggested that the unexplained thrombotic events might be one of the initial presentations of occult malignancy and that thromboprophylaxis should always be considered.  相似文献   
1000.
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