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31.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
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Objective To explore the characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Seven patients with arrhythmogenic right ventricular cardiomyopathy and 34 members of three families were studied. All patients and family members underwent history collection, clinical examination, electrocardiogram (ECG), two-dimensional echocardiography (2-DE) and a signal averaging electrocardiogram. Programmed ventricular stimulation was performed in five patients. Results All patients and family members had normal morphologic characteristics and normal function of the left ventricular by 2-DE. Fourteen persons had abnormal findings indicating ARVC. Five had enlargement of the right ventricular with diffused hypocontractility, eight had thin and systolic bulging in the focal anterior wall with hypokinesia and one had bulging of the inferior wall. Twenty-five persons (seven patients and 18 family members) had abnormal findings in ECG. Positive ventricular late potential was recorded in 13 persons (six patients). Two to three monomorphic ventricular tachycardia (VT) with left bundle branch block (LBBB) configurations were induced in five patients. Ventricular fibrillation was induced in two patients during the electrophysiologic study (EPS). Five patients had very high pacing threshold and/or ineffective pacing in one or many regions of the right ventricle. Two members of one family died suddenly. One member was a dwarf with ARVC. Spontaneous VT with a left bundle branch block (LBBB) configuration was recorded in five patients, polymorphic VT with extremely short coupling interval in one, and premature ventricular complexes with LBBB configuration in 12 (six patients). Conclusion Our familial study strongly suggests that ARVC may be a hereditary disease and it is helpful in the diagnosis and detection of ARVC. The most common manifestations were abnormal structure and function of the right ventricle and abnormal ECG of repolarization and ventricular arrhythmia which originates from the right ventricle.  相似文献   
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This study qualitatively examines the intersections of risk for intimate partner violence (IPV) and HIV infection in South Africa. Eighteen women seeking services for relationship violence were asked semistructured questions regarding their abusive experiences and HIV risk. Participants had experienced myriad forms of abuse, which reinforced each other to create a climate that sustained abuse and multiplied HIV risk. Male partners having multiple concurrent sexual relationships, and poor relationship communication compounded female vulnerability to HIV and abuse. A social environment of silence, male power, and economic constraints enabled abuse to continue. "Breaking the silence" and women's empowerment were suggested solutions.  相似文献   
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Wenger  RH; Wicki  AN; Walz  A; Kieffer  N; Clemetson  KJ 《Blood》1989,73(6):1498-1503
We report here the cloning of the cDNA coding for platelet connective tissue-activating peptide-III (CTAP-III) from a lambda gt11 expression library prepared using messenger RNA (mRNA) isolated from human platelets. The open reading frame of the clone coded for a protein with 128 amino acid residues. Since the precursor of CTAP-III, platelet basic protein (PBP is 94 amino acids long, the 5'-translated region of the cDNA codes for a leader sequence 34 amino acids long. This leader sequence, like the sequence of mature CTAP-III, shows significant homology to the sequence of platelet factor 4 (PF4), the only other platelet specific alpha-granule protein cloned until now, from a human erythroleukemic (HEL) cell line-derived cDNA library. These leader sequences are probably critical for targeting such proteins to the alpha-granule. Northern blot hybridization with platelet and megakaryocyte mRNA shows a single species mRNA of approximately 0.8 kb, suggesting that the corresponding cDNA is full length. The cloning of platelet specific CTAP-III provides additional evidence for the platelet specificity of the cDNA library used.  相似文献   
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Background

Procedural sedation for painful procedures in the emergency department (ED) can be accomplished with various pharmacological agents. The choice of the sedative used is highly dependent on procedure- and patient characteristics and on personal- or local preferences.

Methods

We conducted a multicenter retrospective cohort study of procedural sedations performed in the EDs of 5 hospitals in the Netherlands over a 4 year period to evaluate the efficacy- (success rate of the intended procedure) and safety (incidence of sedation (adverse) events) of propofol sedations compared to midazolam sedations.

Results

A total of 592 ED sedations were included in our study. Patients sedated with propofol (n = 284, median dose 75 mg) achieved a deeper level of sedation (45% vs. 25% deep sedation, p < 0.001), had a higher procedure success rate (92% vs. 81%, p < 0.001) and shorter median sedation duration (10 vs. 17 min, p < 0.001) compared to patients receiving midazolam (n = 308, median dose 4 mg). A total of 112 sedation events were registered for 99 patients. Transient apnea was the most prevalent event (n = 73), followed by oxygen desaturation (n = 18) airway obstruction responsive to simple maneuvers (n = 13) and hypotension (n = 6). Propofol sedations were more often associated with the occurrence of apnea's (20% vs. 10%, p = 0.004), whereas clinically relevant oxygen desaturations (< 90%) were found more often in patients sedated with midazolam (8% vs. 1%, p = 0.001). No sedation adverse events were registered

Conclusion

Propofol is more effective and at least as safe as midazolam for procedural sedation in the ED.  相似文献   
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