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81.
Recently, several techniques and devices have been suggested for achieving endobronchial volume reduction in patients with emphysema. The proposed devices include bronchial blockers, bronchial valves, glues, biomodulators, and stents for bronchial fenestration; all could be positioned only with flexible bronchoscopy. The current available evidence on safety and efficacy for these methods is based on animal studies and patient case series at best; therefore, all the results should be seen with caution. However, the preliminary work reviewed here suggests that most of the proposed techniques can work, and seem to be safer than surgical volume reduction. We do not yet have a proven, widely applicable endobronchial palliative treatment for severe emphysema, but we have a rapidly growing area of new research in interventional pneumology with preliminary results that challenge traditional medical thinking.  相似文献   
82.
BACKGROUND: In the general population, obesity is associated with increased risk of adverse outcomes. However, studies of patients with chronic disease suggest that overweight and obese patients may paradoxically have better outcomes than lean patients. We sought to examine the association of body mass index (BMI) and outcomes in stable outpatients with heart failure (HF). METHODS: We analyzed data from 7767 patients with stable HF enrolled in the Digitalis Investigation Group trial. Patients were categorized using baseline BMI (calculated as weight in kilograms divided by the square of height in meters) as underweight (BMI <18.5), healthy weight (BMI, 18.5-24.9, overweight (BMI, 25.0-29.9), and obese (BMI > or =30.0). Risks associated with BMI groups were evaluated using multivariable Cox proportional hazards models over a mean follow-up of 37 months. RESULTS: Crude all-cause mortality rates decreased in a near linear fashion across successively higher BMI groups, from 45.0% in the underweight group to 28.4% in the obese group (P for trend <.001). After multivariable adjustment, overweight and obese patients were at lower risk for death (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.80-0.96, and HR, 0.81; 95% CI, 0.72-0.92, respectively), compared with patients at a healthy weight (referent). In contrast, underweight patients with stable HF were at increased risk for death (HR 1.21; 95% CI, 0.95-1.53). CONCLUSIONS: In a cohort of outpatients with established HF, higher BMIs were associated with lower mortality risks; overweight and obese patients had lower risk of death compared with those at a healthy weight. Understanding the mechanisms and impact of the "obesity paradox" in patients with HF is necessary before recommendations are made concerning weight and weight control in this population.  相似文献   
83.
OBJECTIVE: Myocardial dysfunction due to coronary arterial lesions is an important complication after Kawasaki syndrome in childhood. Tissue Doppler echocardiography, and strain rate imaging, have shown their value in detecting regional myocardial dysfunction in coronary arterial disease. We aimed to examine the diagnostic value of these methods in patients with coronary arterial lesions after Kawasaki syndrome. METHODS: We assessed regional myocardial function in 17 asymptomatic patients with coronary arterial lesions. Follow-up coronary angiographies were available in all cases. Tissue Doppler echocardiography, and strain rate imaging, were performed at rest and during bicycle exercise. Examination included peak systolic and diastolic velocities, peak systolic strain and strain rate. We enrolled 17 age- and gender-matched persons to serve as a control group. RESULTS: Segmental left ventricular longitudinal function did not significantly differ between the groups with respect to peak systolic velocity, strain, and strain rate. Diastolic abnormalities were identified in segments supplied by coronary arteries with stenotic lesions. Peak diastolic velocity decreased significantly during exercise in those areas, from 77 plus or minus 34 to 59 plus or minus 56 millimetres per second, p smaller than 0.05. Under exercise, a peak diastolic velocity value under 90 millimetres per second enabled us to identify coronary arterial stenosis with a sensitivity of 75 percent and specificity of 64 percent. CONCLUSIONS: After Kawasaki syndrome, diastolic impairment develops in segments supplied by stenotic coronary arteries before systolic dysfunction is detectable. Exercise tissue Doppler echocardiography has the potential to detect these subtle abnormalities, and help monitor progression of the disease.  相似文献   
84.
Renal artery stenosis is considered to be one of the more frequent causes of secondary arterial hypertension. Through its progression renal artery stenosis can cause renal insufficiency, uncontrolled hypertension, and increased cardiovascular morbidity. A thorough clinical examination and the presence of a typical abdominal bruit may provide helpful hints to identify hypertensive patients with possible renal artery stenosis. Testing for renovascular hypertension includes renal artery imaging, assessment of its functional significance, and evaluation for possible revascularization. Renal artery stenosis secondary to fibromuscular dysplasia should be mechanically corrected. For atherosclerotic renal artery stenosis, medical management can be attempted so long as it does not cause a decline of kidney function. In patients who are candidates for renovascular revascularization, surgical intervention can be helpful in improving blood pressure control and possibly halting the progression of renal failure. Randomized controlled trials comparing direct stenting with other surgical methods are necessary to define the best revascularization strategy in patients with renovascular hypertension. A careful follow-up study after renal artery revascularization should evaluate possible benefits in halting the deterioration of chronic renal insufficiency.  相似文献   
85.
Of 1,369 consecutive patients who underwent stent-assisted coronary angioplasty and who were treated with glycoprotein IIb/IIIa inhibitors during these procedures, 17.5% were >or=75 years of age. Compared with patients <75 years old, those >or=75 years of age had similar procedural and in-hospital outcomes but significantly higher rates of hemorrhagic stroke (0.08% vs 1.2%, p <0.001).  相似文献   
86.
Matrix metalloproteinase (MMP)-2 and MMP-9 are believed to play a pathophysiologic role in acute myocardial infarction (MI). The time course of their plasma concentrations in correlation with the extent of myocardial damage is unclear. In a prospective study, 20 patients with proven acute MI underwent successful reperfusion within 6 h after the onset of symptoms. The patients were divided into two groups according to the size of their MI, i.e. large or moderate MI. Plasma concentrations of MMP-2, MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1 were determined on admission, and after 24 h, 48 h, 1 week, 4 weeks, 3 months and 6 months. MMP-2 levels remained unchanged over time in both groups. The plasma concentration of MMP-9 was elevated on admission in patients with large MI versus moderate MI (195 +/- 190 versus 78 +/- 63 ng/ml, p < 0.01) as determined by left ventriculography, and returned to baseline (18 +/- 16 ng/ml) by 1 week after MI. TIMP-1 levels rose slowly in patients with large MI and returned to baseline at 6 months. The ratio of MMP-9 to TIMP-1 was significantly increased on admission in both groups and returned to baseline at 48 h. These data suggest that MMP-9 might play a pathophysiologic role during the early phase of acute MI.  相似文献   
87.
HIV-associated sensory neuropathy (HIV-SN) is a frequent complication of HIV infection and a major source of morbidity. A cross-sectional deep profiling study examining HIV-SN was conducted in people living with HIV in a high resource setting using a battery of measures which included the following: parameters of pain and sensory symptoms (7 day pain diary, Neuropathic Pain Symptom Inventory [NPSI] and Brief Pain Inventory [BPI]), sensory innervation (structured neurological examination, quantitative sensory testing [QST] and intraepidermal nerve fibre density [IENFD]), psychological state (Pain Anxiety Symptoms Scale-20 [PASS-20], Depression Anxiety and Positive Outlook Scale [DAPOS], and Pain Catastrophizing Scale [PCS], insomnia (Insomnia Severity Index [ISI]), and quality of life (Short Form (36) Health Survey [SF-36]). The diagnostic utility of the Brief Peripheral Neuropathy Screen (BPNS), Utah Early Neuropathy Scale (UENS), and Toronto Clinical Scoring System (TCSS) were evaluated. Thirty-six healthy volunteers and 66 HIV infected participants were recruited. A novel triumvirate case definition for HIV-SN was used that required 2 out of 3 of the following: 2 or more abnormal QST findings, reduced IENFD, and signs of a peripheral neuropathy on a structured neurological examination. Of those with HIV, 42% fulfilled the case definition for HIV-SN (n = 28), of whom 75% (n = 21) reported pain. The most frequent QST abnormalities in HIV-SN were loss of function in mechanical and vibration detection. Structured clinical examination was superior to QST or IENFD in HIV-SN diagnosis. HIV-SN participants had higher plasma triglyceride, concentrations depression, anxiety and catastrophizing scores, and prevalence of insomnia than HIV participants without HIV-SN.  相似文献   
88.
89.
A novel DPyDB-C Created by potrace 1.16, written by Peter Selinger 2001-2019 N-18C6 compound was synthesised by linking a pyrene moiety to each phenyl group of dibenzo-18-crown-6-ether, the crown ether, through –HC Created by potrace 1.16, written by Peter Selinger 2001-2019 N– bonds and characterized by FTIR, 1H-NMR, 13C-NMR, TGA, and DSC techniques. The quantitative 13C-NMR analysis revealed the presence of two position isomers. The electronic structure of the DPyDB-C Created by potrace 1.16, written by Peter Selinger 2001-2019 N-18C6 molecule was characterized by UV-vis and fluorescence spectroscopies in four solvents with different polarities to observe particular behavior of isomers, as well as to demonstrate a possible non-bonding chemical association (such as ground- and excited-state associations, namely, to probe if there were forming dimers/excimers). The interpretation of the electronic structure was realized through QM calculations. The TD-CAM-B3LYP functional, at the 6-311+G(d,p) basis set, indicated the presence of predominant π → π* and mixed π → π* + n → π* transitions, in line with the UV-vis experimental data. Even though DPyDB-C Created by potrace 1.16, written by Peter Selinger 2001-2019 N-18C6 computational studies revealed a π-extended conjugation effect with predominantly π → π* transitions, thorough fluorescence analysis was observed a weak emission, as an effect of PET and ACQ. In particular, the WAXD analysis of powder and thin films obtained from n-hexane, 1,2-dichloroethane, and ethanol indicated an amorphous organization, whereas from toluene a smectic ordering was obtained. These results were correlated with MD simulation, and it was observed that the molecular geometry of DPyDB-C Created by potrace 1.16, written by Peter Selinger 2001-2019 N-18C6 molecule played a defining role in the pyrene stacking arrangement.

Herein, we report the formation of a potential supramolecular arrangement mediated by inter- and intra-molecular interactions between di-iminopyrene-dibenzo-18-crown-6-ether molecules.  相似文献   
90.
AIM: To investigate efficacy and safety of cetuximab combined with two chemotherapy regimens in patients with unresectable metastatic colorectal cancer (mCRC). METHODS: Randomized patients received cetuximab with 5-fluorouracil (5-FU), folinic acid (FA) and oxaliplatin (FOLFOX) 6 (arm A, n = 74) or 5-FU, FA and irinotecan (FOLFIRI) (arm B, n = 77). KRAS mutation status was determined retrospectively in a subset of tumors (n = 117). RESULTS: No significant difference was found between treatment arms A and B ...  相似文献   
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