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41.
L S Levin R D Goldner J R Urbaniak J A Nunley W T Hardaker 《Journal of orthopaedic trauma》1990,4(4):432-440
Limb salvage was successful in 25 patients treated for severe grade III upper extremity injuries. In a retrospective review of 20 men and five women, follow-up time averaged 26 months. These high-energy injuries were characterized by massive soft-tissue injury, highly comminuted fractures, and significant neurovascular injury. Farm, industrial, and vehicular accidents accounted for 80% of the cases. Over 50% of the patients had concomitant systemic and/or other significant extremity injuries. Initial treatment consisted of irrigation and debridement and fracture stabilization using external and/or internal fixation. An average of four additional surgical procedures was required to provide soft-tissue coverage and maximum possible functional recovery. Forty-eight percent of the extremities underwent free vascularized or pedicular flaps for coverage or reconstruction. At final follow-up observation, 12% of the extremities rated excellent, 20% rated good, 52% fair, and 16% were poor. Experience gained in managing these severe upper extremity fractures supports the following observations. (a) Grade III open fractures of the upper extremities are frequently associated with significant neural, vascular, and musculotendon injuries. (b) External fixation plays an important role in the stabilization of grossly contaminated fractures. (c) Residual functional disability is common, and most patients do not return to their previous occupation. (d) Staged reconstruction directed toward maximum functional return may take several years. 相似文献
42.
T Hoshino L A Rodriguez K G Cho K S Lee C B Wilson M S Edwards V A Levin R L Davis 《Journal of neurosurgery》1988,69(6):839-842
The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients. 相似文献
43.
Comparative study of two computerized semen motility analyzers 总被引:1,自引:0,他引:1
Semen analysis is one of the primary tests carried out to investigate the infertile male. Subjective evaluation of semen is often prone to observer bias and error. To eliminate this, a number of computerized semen analyzers have recently been introduced into the market and we have evaluated two of the more popular models, the Cell Soft Semen Analyzer and the Hamilton Thorn Motility Analyzer (HTM 2000). The Cell Soft identifies sperm on the basis of user defined values for cell size and luminosity whereas the Hamilton Thorn identifies sperm by motility, and then applies the computer-calculated average size and luminosity of all moving objects to non moving sperm cells. Semen samples from 25 normal donors and 25 subfertile patients were analyzed using these two models of computerized semen analyzers, and also by an experienced technician using both the Makler chamber and the hemocytometer. The results obtained from the two automated analyzers were compared with those obtained by subjective evaluation. Variation in sperm count and motility were analyzed according to the sperm density. Four groups, less than 30 million/ml with debris, less than 30 million/ml, 30-50 million/ml, and greater than 50 million/ml were studied. The majority of patients fit into the first two groups. We observed that the HTM 2000 is superior to the Cell Soft in evaluating sperm count within the patient population group. For our donor population with an average sperm count of greater than 85 million/ml both systems provide extremely accurate counts.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
44.
Allan E. Siperstein M.D. Qui -Hua Zeng M.D. Elizabeth T. Gum M.S. Kenneth E. Levin M.D. Orlo H. Clark M.D. 《World journal of surgery》1988,12(4):528-532
Prior studies in our laboratory have shown that human thyroid neoplasms have a greater adenylate cyclase activity in response to thyroid stimulating hormone (TSH) than does the adjacent histologically normal thyroid tissue. However, there is little information relating activity of the TSH receptor-adenylate cyclase system to the type of thyroid neoplasm. Thyroid tissue from 67 patients was divided by clinical and histological criteria into 6 categories: normal (59), benign tumors (20), stage 1 carcinoma—intrathyroidal involvement only (25), stage 2 carcinomaregional lymph node involvement (6), stage 3 and 4 carcinoma—tissue invasion or distant metastasis (11), and medullary carcinoma (3). Adenylate cyclase activity in an 8,000 x g thyroid membrane preparation was determined in the basal state and when maximally stimulated with 300 mU/ml TSH. The cyclase responsiveness was the ratio of TSH stimulated adenylate cyclase activity compared to basal adenylate cyclase activity. The cyclase responsiveness by category is: normal, 2.8±0.2 (mean ± SEM); benign, 17.9±2.4; stage 1 carcinoma, 9.2±1.9; stage 2 carcinoma, 4.0±1.0; stage 3 and 4 carcinoma, 1.6±0.4; and medullary carcinoma, 1.05±0.04 (for the neoplasms,p <0.02 by ANOVA). Tumor stage was the only correlate with this trend as other prognostic risk factors (age, sex, a history of neck irradiation, or papillary versus follicular histology) showed no difference in cyclase responsiveness. These studies demonstrate a consistent inverse correlation between adenylate cyclase responsiveness and tumor stage or aggressiveness. Cyclase responsiveness appears to have clinical application for predicting which thyroid tumors will behave aggressively.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.
Supported in part by the Medical Research Service of the Veterans Administration. 相似文献
Resumen Estudios previos en nuestro laboratorio han demostrado que los neoplasmas tiroideos humanos poseen una mayor actividad de adenilato ciclasa en respuesta a la administración de hormona estimulante de la tiroides (TSH) que el tejido tiroideo histológicamente normal adyacente. Sin embargo, existe muy poca información sobre la relation de la actividad del sistema receptor de TSH-adenilato ciclasa y el tipo del neoplasma tiroideo. Tejido tiroideo proveniente de 67 pacientes fue dividido mediante criterios chlínicos e histológicos en 6 categorias: normal (59), tumores benignos (20), extensión intratiroidea solamente en estado 1 (25), carcinoma-extensión ganglionar regional en estado 2 (6), carcinoma-invasión tisular o metástasis distantes en estados 3 y 4 (11), y carcinoma medular (3). La actividad de la adenilato ciclasa en una preparación de membrana tiroidea de 8,000 × g fue determinada en el estado basai y en estado de maxima estimulación con 300 mU/ml TSH. El grado de respuesta de la ciclasa fue la tasa de actividad de la adenilato ciclasa estimulada por TSH comparada con la actividad basai de la adenilato ciclasa. El grado de respuesta por categorías fue: normal, 2.8±0.2; tumor benigno, 17.9±2.4; carcinoma estado 1, 9.2±1.9; carcinoma estado 2, 4.0±1.0; carcinoma estados 3 y 4, 1.6±0.4; y carcinoma medular, 1.05±0.04 (para los neoplasmas,p < 0.02 por ANOVA). El estado del tumor apareció como el único factor de correlatión con esta gradación, ya que otros factures de pronóstico (edad, sexo, historia de irradiación cervical, histología papilar versus folicular) no demostraron diferencia en cuanto al grado de respuesta de la ciclasa. Estos estudios demuestran una consistente relación inversa entre el grado de respuesta de la adenilato ciclasa y el estado o agresividad tumoral. El grado de respuesta de la ciclasa parece tener aplicación clínica para predecir qué tumores tiroideos se habrán de comportar en forma agresiva.
Résumé Les études antérieures provenant de nos laboratoires ont démontré une augmentation de l'activité enzymatique de l'adénylate-cyclase en réponse à la thyroïd stimulating hormone (TSH) dans le tissu thyroïdien humain tumoral, par rapport au tissu thyroïdien adjacent normal. Cependant il existe peu de données concernant l'activité du système récepteur TSH/adénylatecyclase par rapport au type de tumeur de la thyroïde. Les tissus thyroïdiens provenant de 67 patients différents ont été repartis en 6 groupes selon des critères cliniques et histologiques: normal (59), tumeur bénigne (20), cancer stade 1 (intrathyroïdien uniquement) (25), cancer stade 2 (envahissement ganglionnaire régional) (6), cancer stade 3 et 4 (envahissement tissulaire avoisinant ou métastases à distance (11), et cancer médullaire (3). A partir d'une préparation de membrane thyroïdienne centrifugée à 8,000 × g, l'activité de l'adénylate-cyclase a été déterminée en l'état basai et après stimulation maximale par 300 mU/ml de TSH. La réponse enzymatique a été mesurée comme étant le rapport de l'activité stimulée par la TSH/activité basale. Les résultats selon les 6 groupes étaient (moyen±ET): tissu normal, 2.8±0.2; tumeur bénigne, 17.9±2.4; cancer stade 1, 9.2±1.9; cancer stade 2, 4.0±1.0; cancers stade 3 et 4, 1.6±0.4; et cancer médullaire, 1.05±0.04 (p < 0.02 par l'analyse de variance pour les néoplasies). Le stade tumoral était la seule variable corrélée avec l'activité enzymatique. L'activité enzymatique n'était pas corrélée avec l'âge, le sexe, les antécédents d'irradiation cervicale antérieure ou l'histologie (papillaire vs. folliculaire). Ces études montrent un rapport inversement proportionnel entre l'activité d'adénylate-cyclase et le degré d'agressivité tumorale ou le stade. La réponse d l'adénylate-cyclase paraît avoir une application clinique: prévoir quelles tumeurs thyroïdiennes auront une évolution agressive.
Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.
Supported in part by the Medical Research Service of the Veterans Administration. 相似文献
45.
Shinichiro Kitada Kumiko Kato Alan J. Wein Robert M. Levin 《Neurourology and urodynamics》1989,8(3):255-262
We were able to produce two highly reproducible experimental models (in the rabbit) that demonstrated a high degree of reflex bladder contractile activity. In one model, a somatovesical reflex was induced by touching or pinching the perineal area. This reflex may be organized through a neurogenic reflex at the spinal level. In another model, rhythmic bladder contractions were produced by distal urethral constriction in the absence of bladder distension. These rhythmic contractions were thought to be due to a supraspinal reflex. In both types of contractile reflexes, intravenous administration of hexamethonium inhibited the reflex contractile activity virtually completely, intravenous atropine inhibited over 90% of the induced contractile activity, thus suggesting that these contractions were mediated reflexly through cholinergic stimulation. These two models of reflex bladder contractions should be useful for the study of hyperreflexic bladders. 相似文献
46.
Multivariate flow cytometric analysis and sorting of mouse bone marrow cells viably stained with Hoechst 33342 (HO) was utilized to obtain a subpopulation enriched at least 30- to 60-fold for clonogenic megakaryocyte precursors (CFU-Meg). HO fluorescence intensity, forward light scatter, and perpendicular light scatter were measured on each HO-stained bone marrow cell as it passed through a dual beam flow cytometer. Cells were sorted on the basis of their light scattering and HO fluorescence intensity properties. The sorting region which included cells with high forward light scatter, low perpendicular light scatter, and low (0.1-0.65 times the modal channel) HO fluorescence intensity contained approximately 0.6% CFU-Meg. Of all CFU-Meg, 75% were contained in the light scatter gate, and 56% of all CFU-Meg were in the low HO-sorting region. This technique offers a simple, one-step procedure to obtain preparations enriched in murine clonogenic megakaryocyte precursors. 相似文献
47.
Nontraumatic childhood peroneal mononeuropathy is uncommon and should initiate a search for surgically correctable causes. In 3 children, 2 age 12 years and 1 age 13 years, unilateral footdrop developed over a few days to a month. Electrodiagnostic findings demonstrated lesions with maximal or exclusive involvement of the deep peroneal nerve. Radiologically, bony exostoses were identified at or near the fibular head in each patient. In 2 patients, the lesions were clinically occult. An osteochondroma was removed from each patient and 2 patients had excellent clinical recoveries. 相似文献
48.
Levin Adeera; Djurdjev Ognjenka; Duncan John; Rosenbaum Debbie; Werb Ron 《Nephrology, dialysis, transplantation》2006,21(2):370-377
Haemoglobin (Hgb) levels are known to be associated with numerousadverse outcomes in both chronic kidney disease (CKD) and non-CKDpatients. This analysis evaluates the association of baseline haemoglobinlevels on survival in CKD patients, who are followed by nephrologists,irrespective of glomerular filtration rate (GFR), prior to initiationof renal replacement therapy (RRT) and erythropoietin hormonereplacement therapy. Analysis of data from the provincial database (PROMIS, PatientRegistration and Outcome Management Information System) in BritishColumbia, Canada, was undertaken. Records used for the analysisincluded all CKD patients at first registration: GFR <60ml/min/1.73 m2, not yet on dialysis, starting from May 1998to October 2002, and who had complete data (defined as age andgender, diabetic status, eGFR and Hgb levels). The primary objective of this study was to determine the associationof Hgb and survival controlling for eGFR at first registrationvalue, age, gender and diabetic status. Multivariate Cox proportionalhazards analysis with time to death as outcome variable wasperformed. The cohort included 3028 patients: the mean age was 65 years,28% were diabetic, and the mean eGFR in the cohort was 21 ml/min/1.73m2. The cohort is representative of the BC CKD and dialysispopulation regarding ethnicity: 64% Caucasian, 32% Asian. Medianfollow-up was 27 months, 1 year survival was 0.92, 2 year survivalwas 0.85. Hgb at initial registration is a statistically independentpredictor of survival (RR = 0.875 for every 10 g/l, 95% CI:0.8350.917, P = 0.0001), after adjusting for age, gender,diabetic status and baseline eGFR. Further analysis, controllingfor RRT, demonstrated a similar association between Hgb andsurvival (RR = 0.853 for every 10 g/l, 95% CI: 0.7990.910,P = 0.0001), after adjusting for above variables. Substantialvariation in Hgb values exists at all GFR levels. These findings underscore the importance of evaluating Hgb atall GFR levels, and the need to study the impact of modificationof Hgb at different GFR levels on survival. 相似文献
49.
Clinical experience with short-time hemodialysis. 总被引:4,自引:0,他引:4
After at least 6 months on conventional hemodialysis (cellulosic dialyzers, acetate dialysate, and a 3- to 4-hour treatment time), 56 patients were changed to short-time hemodialysis (less than 180 minutes) using polysulfone dialyzers and bicarbonate-containing dialysate. Treatment time decreased (191 +/- 5 v 147 +/- 5 min; P = 0.001), while Kt/V (1.22 +/- 0.04 v 1.29 +/- 0.06; P = NS) and normalized protein catabolic rate (pcr) (1.10 +/- 0.05 v 1.10 +/- 0.07 g/kg/d; P = NS) remained constant. When compared with the conventional period, 30 months of short-time hemodialysis resulted in no changes in predialysis blood pressure (BP) (151 +/- 2/84 +/- 1 v 151 +/- 2/86 +/- 1 mm Hg), postdialysis BP (144 +/- 2/81 +/- 1 v 143 +/- 3/84 +/- 1 mm Hg), interdialytic weight gain (2.4 +/- 0.1 v 2.7 +/- 0.2 kg), or blood urea nitrogen (BUN) (26.1 +/- 0.71 v 25.3 +/- 1.07 mmol/L [73 +/- 2 v 71 +/- 3 mg/dL]). Shorter treatment times were not associated with an increase in intradialytic complications. Actually, the frequency (%) of dialysis treatments associated with nausea (5.94 +/- 1.33 v 2.21 +/- 0.52), vomiting (3.12 +/- 0.87 v 0.54 +/- 0.14; P less than 0.05), headaches (5.60 +/- 1.13 v 2.03 +/- 0.52; P less than 0.05), and back pain (0.91 +/- 0.25 v 0.05 +/- 0.05; P less than 0.05) was decreased.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
50.
Mathematical approaches to the evaluation of the severity of the pathological process were used to develop an objective quantitative method to assess the severity of ventricular arrhythmias. The method is highly informative and reliable. It may be useful in the control of the efficacy of antiarrhythmic therapy and in the application of a differential approach to choice of therapy strategy for the patients. 相似文献