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41.
The authors report on their experience with internal jugular vein catheterization with temporary and tunnelled cuffed hemodialysis catheters in 527 patients from 1991 to 2001, using ultrasound guidance and monitoring of catheter placement by endocavitary electrocardiography. The incidence of successful puncture and cannulation using ultrasound was 99.62%. The majority of patients had catheters inserted on the first pass (93%) and fewer attempts were required (range, 2 to 5). In the first year of the procedure in 1991, we observed two cases of accidental puncture of the carotid artery because of an error in ultrasound localization of the neck vessel. Arrhythmias were not observed during this procedure. Right atrial electrocardiography was successful on 504 occasions (96.83%), and correct catheter placement was confirmed by plain chest-X-ray in the first 100 patients. The results confirm that real-time ultrasound guidance for catheter insertion is superior to tradi-tional techniques relying on anatomic landmarks and should be adopted as the standard of care. Ultrasound guidance and EC-ECG improves both the success and the safety of internal jugular catheter insertion. The authors propose that EC-ECG be validated as a technique in compliance with recent Food and Drug Ad-ministration guidelines regarding the location of central venous catheter tips.  相似文献   
42.
Equilibrium red blood cell phleboscintigraphy of the lower limbs for the diagnostic management of chronic venous disease has been proposed. The aim of this study was to verify the correlation of the phleboscintigraphic assessment of chronic venous disease with the clinical grading of the severity of the disease, since other diagnostic modalities have been recently demonstrated a poor and only partial correlation. Equilibrium Tc-99m-red blood cell phleboscintigraphy was performed in 27 patients with chronic venous disease. Scintigraphic images of 52 limbs were classified according to a four-class qualitative grading of the severity of the venous disease, and a quantitative scintigraphic index (saphena /femoral ratio) was assigned to each limb. The scintigraphic qualitative grading showed a highly significant correlation with the clinical grading (Rs=0.82, p<0.01), a good interobserver and intraobserver agreement (86.5% and 92.3%, respectively) and more than 90% sensitivity and specificity to identify the categories "minimal or no chronic venous disease" or "more significant disease" (assessed according to the Bayes theorem). Sensitivity and specificity results for the quantitative assessment were not as good. Phleboscintigraphy correlates well with the clinical grading of the severity of chronic venous disease of the lower limbs and may have potential as a valuable diagnostic tool for the noninvasive assessment of chronic venous disease.  相似文献   
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锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
46.
Summary A clinico-epidemiological study is reported concerning a group of 306 parenteral drug addicts (PDAs), 71 of whom were affected with the lymphadenopathy syndrome (LAS); all were followed-up between 1981 and 1984. Although full-blown acquired immune deficiency syndrome (AIDS) was observed only in one case, none of the other patients examined have undergone complete recovery so far. The results of our study point to a wide circulation of LAV/HTLV III among our group of PDAs, starting at least as early as 1981 and preceding by a few months the development of clinical signs and symptoms of LAS. A peak incidence of the latter was observed during the winter of 1983/1984, running parallel with a marked increase in seropositives for LAV/HTLV III antibody. Drug addiction, sexual promiscuity and a low standard of living all seem to play a decisive role in the spread of the infection and, consequently, of the diseases related to it (LAS, AIDS-related complex and AIDS). In fact, PDAs appear to represent the major source of the disease in Italy.
Epidemie von LAV/HTLV III-Infektion bei Drogenabhängigen in Mailand: Serologische Untersuchungen und klinische Verlaufsbeobachtung
Zusammenfassung Eine klinisch-epidemiologische Studie wurde bei einer Gruppe von 306 Rauschgiftsüchtigen durchgeführt, von denen 71 an generalisierter Lymphadenopathie (LAS) leiden; sie wurden zwischen 1981 und 1984 kontinuierlich betreut. Obwohl nur in einem einzigen Falle die Entwicklung eines vollständigen erworbenen Immundefizienz-Syndroms (AIDS) beobachtet wurde, wurde andererseits bisher bei keinem der anderen Patienten eine eindeutige Heilung nachgewiesen. Die Ergebnisse unserer Untersuchung weisen auf eine ausgebreitete Zirkulation des Virus in unserer Drogensüchtigen-Gruppe mindestens seit 1981 hin, ein Phänomen, welches klinischen Lymphadenopathie-Zeichen und Symptomen um einige Monate vorausging. Eine auffällig hohe Inzidenz dieser Krankheit wurde während des Winters 1983/1984 parallel zu einem steilen Anstieg der LAV/HTLV III-Seropositivität beobachtet. Rauschgiftsucht, geschlechtliche Promiskuität und niedriges Lebensniveau scheinen eine entscheidende Rolle in der Ausbreitung der Infektion und der mit ihr assoziierten Krankheitsbilder (LAS, AIDS related complex, AIDS) zu spielen. Drogensüchtige scheinen die größte Infektionsquelle in Italien darzustellen.
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47.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
48.
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
49.
This paper concerns a method for assessing adult age based on the relationship between age and the third molar maturity index (I3M), which is related to the measurement of the open apices of the third molar. Furthermore, this method was compared to those based on Demirjian’s stages G and H. The sample consisted of 906 Caucasian individuals aged between 14 and 23 years (53.6% females and 46.4% males). Orthopantomographs were analyzed by two observers and calibrated by means of the concordance correlation coefficient for the reproducibility of the third molar maturity index (I3M) and κ statistics for reproducibility of the Demirjian stages. Probabilities for an individual to be older than 18 years of age (adult age) were derived using the measurements of the third molar maturity index (I3M). These results were exploited to set out a threshold value to assign an individual to juvenile or adult age. A cutoff value of I3M = 0.08 was taken. The sensitivity of this test was 70% and specificity was 98%. Furthermore, the proportion of individuals with a correct classification was 83%. The results of the test showed a better specificity when compared to the choice of stage G and a better sensitivity when compared to the choice of stage H for adult age.  相似文献   
50.
BACKGROUND: Growth hormone (GH) replacement in adult GH-deficient (GHD) patients is reported to have a long-term beneficial effect on muscle mass and function, these effects being greater in young males and in adult-onset compared with those with childhood-onset GHD. To date, more discordant data are reported on the degree of muscle impairment in untreated GHD patients, due to the large heterogeneity of this syndrome. METHODS: Muscle maximum total isotonic strength (ST), lower limb maximum power output (W), maximum aerobic capacity (VO(2)max) and body composition (by tetrapolar bio-impedentiometry) were evaluated in seven short-stature adults with childhood-onset GHD and in seven age-matched normal-stature controls with comparable lifestyle and daily physical activity. RESULTS: Significant differences were found in body composition between control subjects and GHD patients, who presented higher adiposity (mean BMI+/-SD: GHD, 27.8+/-5.8 kg/m(2); controls, 22.1+/-0.8 kg/m(2); p=0.047), larger fat mass (GHD, 21.8+/-10.7 kg; controls, 8.8+/-3.5 kg; p=0.008), and lower fat-free mass (GHD, 65.8+/-11.4 %; controls, 87.0+/-6.5 %; p=0.002). In absolute terms, GHD patients attained significantly lower values in ST (GHD, 2479+/-493 N; controls, 4578+/-1476 N; p=0.008), W (GHD, 1092+/-452 W; controls, 1910+/-781 W; p=0.035) and VO(2)max (GHD, 1.68+/-0.40 l/min; controls, 2.67+/-0.84 l/min; p=0.035) than those attained by controls. The differences were still evident when the results were normalized by unit body mass, whereas they disappeared when the parameters were expressed per unit fat-free mass, suggesting for these patients the presence of an intrinsic muscle function in the same range as that of control subjects. CONCLUSIONS: Middle-aged and short-stature adults with childhood-onset GHD, who received discontinuous pit-GH substitution therapy only during childhood and have uncorrected long-lasting GHD, still retain a normal intrinsic muscle capability in attaining isotonic strength, generating anaerobic power as well as accomplishing oxidative processes. Nonetheless, it is not known which age-dependent evolution in motor dysfunction could be expected in this subgroup of GHD patients, when ageing processes add up to hormonal deficiencies.  相似文献   
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