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91.
OBJECTIVE: To assess the modern morbidity of hemoptysis and the contribution of therapeutic bronchial artery embolization to its management. METHODS: Medical record review of patients admitted for the treatment of hemoptysis from January 1991 to November 1995 and of patients who had therapeutic bronchial artery embolization from June 1986 to August 1995. Hemoptysis was labeled major or minor. RESULTS: A total of 138 patients were admitted with hemoptysis, 31 with major and 107 with minor hemoptysis. No emergency pulmonary resections were required. Mean follow-up was 13.5 months. Mortality was 29.7% (41/138) but was caused by bronchial bleeding in only 4.3% (6/138). Twenty-six patients underwent therapeutic bronchial artery embolization (mean follow-up [range], 14 months [0.3-69.0 months]). The initial success rate (no further bleeding during the initial admission) was 85% (22/26). The long-term success rate (no further bleeding during follow-up) was 58% (15/26). Only 2 patients with therapeutic bronchial artery embolization died of further hemoptysis. CONCLUSIONS: Hemoptysis signals life-threatening diseases. Therapeutic bronchial artery embolization is a good treatment adjunct to control bronchial bleeding and reduces the need for high-risk emergency lung resections.  相似文献   
92.
We measured the photopic spectral sensitivity of multiunit activity in the torus longitudinalis and optic tectum of goldfish. Since negative contrast stimuli are most effective for exciting torus longitudinalis, spiking activity was evoked by the shadow of a disc moving through a monochromatic light beam projected upon a screen. The amount of activity evoked in torus longitudinalis generally increased with the monochromatic stimulus radiance at the same rate for all wavelengths, indicating a univariant response. Spiking activity in tectum, however, increased at different rates across the spectrum, indicating color-dependent responses. The action spectra for torus longitudinalis were all similar and relatively flat as expected of a homogeneous, broad-band luminance processing system, and about 1 log unit more sensitive than the tectal action spectra. The latter generally displayed sharp peaks and dips in sensitivity indicative of opponent processing.  相似文献   
93.
The efficacy and safety of oral sildenafil, a potent inhibitor of phosphodiesterase type 5, were evaluated in men with diabetes mellitus and erectile dysfunction (ED). Twenty-one men (aged 42-65 years) were enrolled in a double-blind, placebo-controlled, three-way crossover study conducted in two parts. In part I, the effect of a single dose (25 mg or 50 mg) of sildenafil or placebo on penile rigidity was assessed by penile plethysmography during visual sexual stimulation. In part II, daily diary records of erectile activity and a global efficacy question were used to evaluate once-daily dosing with 25 mg or 50 mg of sildenafil or placebo for 10 days. After a single 50 mg dose of sildenafil, the adjusted geometric mean duration (min) of penile rigidity >60% at the base of the penis during visual sexual stimulation was significantly increased (10.1 min) compared with placebo (2.8 min; p = 0.0053). In part II, sildenafil significantly increased the number of erections considered sufficiently hard for vaginal penetration compared with placebo (p = 0.0005). Improved erections were reported by 50% and 52% of patients treated with 25 mg and 50 mg of sildenafil, respectively, compared with 10% of those receiving placebo (p values < 0.05). Adverse events were mostly mild or moderate in nature and included muscular pains, headache, and dyspepsia. Sildenafil is a well-tolerated and potentially efficacious oral treatment for ED in men with diabetes mellitus.  相似文献   
94.
Understanding the mechanisms responsible for photodamage to the skin is most important for dermatology. 3-D cultures have been used as tools to mimic the in vivo situation for several years. We irradiated such a system containing human dermal fibroblasts cultured in collagen gels, a well-known model considered to be a dermal equivalent, which reproduces the interaction between cells and the surrounding extracellular matrix. The effects of solar irradiation (315-800 nm) on the steady-state levels of the mRNAs of extracellular matrix components (type I and III collagens) and their degrading enzymes (interstitial collagenase, MMP-1 and stromelysin 1, MMP-3) were measured. Exposure to low levels of solar radiation (0-10 J cm-2 in the UVA, i.e. suberythemal UVA doses) caused a transient decrease in type I procollagen mRNA, an increase in MMP-mRNA, and no change in type III procollagen mRNA steady-state levels. These results describe the early changes in the connective tissue of the skin following exposure to low-level solar stimulation, and may help explain the long-term changes in photodamaged skin.  相似文献   
95.
K. R. Paap and R. W. Noel (1991) observed a striking effect in which low-frequency exception words were pronounced faster under a larger memory load although other types of words slowed down. This effect strongly favored dual-route models of pronunciation. S. E. Bernstein and T. H. Carr (1996) reported that only certain selected readers produced Paap and Noel's effect, suggesting individual differences in reading-system architecture. P. M. Pexman and S. J. Lupker (1998) criticized Bernstein and Carr's finding as artifactual and failed to replicate it with a different way of selecting readers. They also failed to support an alternative individual-difference hypothesis of their own. In the current article, the authors developed a new approach to identifying individual differences and applied the approach to a variety of data. They found little evidence of systematic individual differences in the occurrence of Paap and Noel's effect, and indeed, they found little evidence that the effect could be replicated at all. Therefore, they gave up. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
BACKGROUND: There is controversy regarding the most appropriate investigation for suspected colorectal carcinoma. We offered these patients same-day flexible sigmoidoscopy (FS) and double-contrast barium enema (DCBE). METHODS: We reviewed the results of 117 consecutive adult patients. All patients underwent FS followed by DCBE on the same day. The radiographs were reviewed by two of the authors who were blinded to the clinical information, flexible sigmoidoscopy reports, and the original DCBE report. RESULTS: One hundred seventeen patients made up the study population. Thirty-four of the 117 patients had polyps and/or carcinoma. Three malignant tumours were detected by DCBE; one of these was also seen on FS, and the other two cancers were out of FS range. Fifty-three polyps were found by FS; nine were removed by biopsy prior to the enema examination. Of the 44 remaining polyps, DCBE failed to detect 87% of the 0-9-mm group and 67% of the >9-mm group. Ten polyps were seen only on DCBE; seven of these 10 were beyond the range of the sigmoidoscope, and the three remaining polyps were less than 5 mm. CONCLUSION: DCBE is insensitive in the detection of rectosigmoid polyps. FS should continue to be used as a complementary examination to DCBE in the investigation of suspected colorectal carcinoma.  相似文献   
97.
98.
The recognition of a pathologic entity is only the first step in the chain of events which must be performed for accurate diagnoses and appropriate patient management. Other steps include selection of the type of biopsy to be performed; proper biopsy technique, instrumentation and specimen handling; appropriate fixation; detailed documentation; and postoperative patient instructions. If the clinician performs each step carefully and correctly, the patient is ensured of receiving an accurate diagnosis in the shortest possible period of time.  相似文献   
99.
A membrane-bound protease induced by sulfur mustard in cultured normal human epidermal keratinocytes (NHEK) was purified and partially characterized. Maximum enzyme stimulation occurred at 16 hr after normal human epidermal keratinocytes were exposed to 300 microM sulfur mustard. Purification to homogeneity of the protease was accomplished by Triton X-100 solubilization, ultracentrifugation, and dialysis, followed by ion-exchange chromatography through DEAE-cellulose and finally hydrophobic column chromatography through phenyl Sepharose. Analysis of the purified enzyme by SDS-PAGE revealed a single polypeptide at the 80 kDa region. Further investigation of biochemical properties showed that a synthetic serine-specific Chromozym TRY peptide and the physiological protein laminin were good substrates for this enzyme. Moreover, this enzyme was inhibited mostly by the serine-protease inhibitors leupeptin and di-isopropyl fluorophosphate and not by the cysteine protease inhibitor E-64 or the metalloprotease inhibitor 1,10-phenanthroline (Component H, CH), indicating the serine protease nature of this enzyme. This enzyme had a pH optimum in the range of 7.0 to 8.0. Amino acid sequencing of the purified enzyme revealed that this enzyme belongs to the endopeptidase family (serine protease), and is homologous with a mammalian-type bacterial serine endopeptidase that can preferentially cleave K-X, including K-P. These results suggest that serine-protease stimulation may be one of the mechanisms of mustard-induced skin blister formation, and that some specific serine-protease inhibitors may be useful for the treatment of this sulfur mustard toxicity.  相似文献   
100.
A new technique, the dual voltage versus time curve (V-t) integration technique, is presented as a much faster method to obtain time-dependent dielectric breakdown (TDDB) acceleration parameters (α and τ) of ultrathin gate oxides compared to conventional long-term constant voltage stress tests. The technique uses V-t curves measured during highly accelerated constant or ramped current injection breakdown tests. It is demonstrated that the technique yields acceleration parameters that are statistically identical to values obtained from long-term constant voltage TDDB tests. In contrast to traditional TDDB tests, the proposed technique requires over an order of magnitude less testing time, a smaller sample size, and can be used during production monitoring  相似文献   
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