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101.
Primary focal segmental glomerulosclerosis (FSGS) is a lesion associated with a poor prognosis and results in end-stage renal disease after 5 to 10 years. Based on past experience, many nephrologists have considered primary FSGS a lesion that is steroid resistant and therefore are reluctant to offer steroids as treatment. Recent data, however, have demonstrated that patients with primary FSGS have a response to steroid therapy that is considerably better than had been described. Thus, it may be that nephrologists have been more "steroid reluctant" than the lesion is steroid resistant. To better understand this issue we review the clinical course and response to therapy in patients with primary FSGS. 相似文献
102.
Prosthetic valve endocarditis: superiority of surgical valve replacement versus medical therapy only
VL Yu GD Fang TF Keys AA Harris LO Gentry PC Fuchs MM Wagener ES Wong 《Canadian Metallurgical Quarterly》1994,58(4):1073-1077
The objective of our study was to assess the long-term outcome of patients with prosthetic valve endocarditis. We used a multicenter, prospective, observational study design. Six university teaching hospitals with high volume cardiothoracic surgery participated. Seventy-four patients with prosthetic valve endocarditis as defined by explicit, objective criteria were selected for participation. All patients were followed up prospectively for 1 year. Thirty-one percent and 69% had development of endocarditis within 60 days of valve insertion ("early") and after 60 days ("late"), respectively. The most common causes were Staphylococcus epidermidis (40%), Staphylococcus aureus (20%), streptococcal species (18%), and aerobic gram-negative bacilli (11%). Physical signs of endocarditis (new or changing murmur, stigmata, emboli) were seen in 58%. At 6 months and 12 months, mortality was 46% and 47%, respectively. Surgical replacement of the infected valve led to significantly lower mortality (23%) as compared with medical therapy alone (56%), as assessed by both univariate and multivariate analyses (p < 0.05). Improved outcome was seen for the surgical group even when controlling for severity of illness at time of diagnosis. From these findings we conclude that accurate assessment of outcome in prosthetic valve endocarditis requires long-term follow-up of at least 6 months following diagnosis. Surgical therapy warrants greater scrutiny; evaluation in controlled clinical trials is appropriate. 相似文献
103.
Paired-pulse plasticity is typically used to study the mechanisms underlying synaptic transmission and modulation. An important question relates to whether, under physiological conditions in which various opposing synaptic properties are acting in parallel, the net effect is facilitatory or depressive, that is, whether cells further or closer to threshold. For example, does the net sum of paired-pulse facilitation (PPF) of excitatory postsynaptic potentials (EPSPs), paired-pulse depression (PPD) of inhibitory postsynaptic potentials (IPSPs), and the hyperpolarizing slow IPSP result in depression or facilitation? Here we examine how different time-dependent properties act in parallel and examine the contribution of gamma-aminobutyric acid-B (GABAB) receptors that mediate two opposing processes, the slow IPSP and PPD of the fast IPSP. Using intracellular recordings from rat CA3 hippocampal neurons and L-II/III auditory cortex neurons, we examined the postsynaptic responses to paired-pulse stimulation (with intervals between 50 and 400 ms) of the Schaffer collaterals and white matter, respectively. Changes in the amplitude, time-to-peak (TTP), and slope of each EPSP were analyzed before and after application of the GABAB antagonist CGP-55845. In both CA3 and L-II/III neurons the peak amplitude of the second EPSP was generally depressed (further from threshold) compared with the first at the longer intervals; however, these EPSPs were generally broader and exhibited a longer TTP that could result in facilitation by enhancing temporal summation. At the short intervals CA3 neurons exhibited facilitation of the peak EPSP amplitude in the absence and presence of CGP-55845. In contrast, on average L-II/III cells did not exhibit facilitation at any interval, in the absence or presence of CGP-55845. CGP-55845 generally "erased" short-term plasticity, equalizing the peak amplitude and TTP of the first and second EPSPs at longer intervals in the hippocampus and auditory cortex. These results show that it is necessary to consider all time-dependent properties to determine whether facilitation or depression will dominate under intact pharmacological conditions. Furthermore our results suggest that GABAB-dependent properties may be the major contributor to short-term plasticity on the time scale of a few hundred milliseconds and are consistent with the hypothesis that the balance of different time-dependent processes can modulate the state of networks in a complex manner and could contribute to the generation of temporally sensitive neural responses. 相似文献
104.
Current wisdom holds that health care is a business and "as such must abide by market principles." Most nurses are not well enough versed in economic theories to credibly critique health care delivery decisions based on economic theories. The relationship of market principles to health care realities is described in basic terms to encourage nurses to "optimize patient care and influence health care policy." Physicians, who control all access points to the health care system, have enjoyed a 40-year market dominance that is "rapidly being replaced by insurance companies and for-profit investors." Providers' decisions to treat or not to treat are strongly influenced by whether the patient is in a fee-for-service or capitated payment environment. 相似文献
105.
We recently reported that washed platelets (WP) activated with ADP and expressing surface-bound vWF aggregated in flow through small tubes or in a cylindrical couette device at physiological shear rates of G = 300 s(-1)-1000 s(-1) in the absence of exogenous ligands, with GPIb-vWF partially, and activated GPIIb-IIIa totally required for the aggregation. We have now extended these studies to aggregation of platelets "activated" with ristocetin or thrombin. Washed platelet suspensions with added soluble vWF and ristocetin (0.3-0.75 mg/ml), or activated with thrombin (0.01-0.5 U/ml) but no added ligand, were sheared in a coaxial cylinder device at uniform shear rate, G = 1000 s(-1). The collision capture efficiency (alphaG) with which small aggregates form (= experimental/calculated initial rates of aggregation) was correlated with vWF platelet binding assessed by flow cytometry. The vWF-GPIb interaction was exclusively able to support ristocetin-mediated shear aggregation of metabolically active platelets, with very few vWF monomer equivalents bound per platelet (representing < or = 10 molecules of 10 million Da) required to yield high capture efficiencies (alphaG = 0.38+/-.02; n = 11), suggesting rapid and stable bond formations between vWF and GPIb. However, platelet surface-expressed vWF, generated by addition of thrombin to washed platelets, was found to mediate platelet aggregation with alphaG = 0.08+/-.01 (n = 6), surprisingly comparable to that previously reported for WP and ADP activation. Blocking the GPIIb-Illa receptor decreased alphaG by 95+/-3% (n =3), while a monoclonal antibody to the vWF site on GPIb caused a 49+/-7% (n = 8) decrease in alphaG. The partial role for GPIb thus appears to reflect a facilitative function for increasing contact time between flowing platelets, and allowing engagement of the GPIIb-IIa receptor to yield stable attachment. 相似文献
106.
ES Wiener RJ Touloukian BM Rodgers JL Grosfeld EI Smith MM Ziegler AG Coran 《Canadian Metallurgical Quarterly》1996,31(8):1166-1169
The members of the Section on Surgery of the American Academy of Pediatrics were surveyed to determine the practice of North American pediatric surgeons in infants with inguinal hernia (IH). Case-scenario multiple-choice-design questionnaires regarding hernias and hydroceles were sent to all members of the Surgical Section, and responses were received from 292 (50%). In healthy full-term infant boys with asymptomatic reducible IH, 82% of responders perform repair electively, no matter what the age or weight. In full-term girls with a reducible ovary, 59% perform surgery at the next available time; if the ovary is nonreducible but asymptomatic, 44% operate emergently or urgently and 42% at the next elective slot. In former preemies, the pattern of repair is as follows. (1) For those recently discharged after 2 months in the neonatal intensive care unit (NICU) with reducible IH, 65% perform the repair when convenient. (2) A general anesthetic is used in 70%; 15% use spinal anesthesia, and 11% use caudal block with sedation. (3) If the repair is done in the hospital outpatient (same-day) unit, 36% wait until 50 weeks postconception (PC) and 33% wait until 60 weeks PC. (4) if the baby's weight is at least 1,000 g. 71% perform the repair before discharge. The pain control choice after childhood IH repair is Tylenol for 30%, local infiltration biquivacaine for 30%, caudal block for 22%, regional block for 11%, and Tylenol/codeine combined for 7%. In 6-week-old full-term infants with communicating hydroceles without definite "hernia," two thirds treat as an IH with elective repair as soon as possible. With respect to contralateral exploration in infants with unilateral IH, 65% perform it in males if they are < or = 2 years of age and 84% use it in females of up to 4 years of age. This approach is not influenced by presenting side, presence of hydrocele, or history of prematurity. Laparoscopic evaluation of the contralateral IH is performed by only 6% of responders, 40% of whom use the open ipsilateral sac for laparoscope introduction. 相似文献
107.
GG Stone MM Chengappa RD Oberst NH Gabbert S McVey KJ Hennessy M Muenzenberger J Staats 《Canadian Metallurgical Quarterly》1993,5(3):378-385
The polymerase chain reaction was employed to correlate Salmonella serovars isolated from fecal material of greyhounds suffering from gastroenteritis with those isolated from the diet fed to the greyhounds prior to onset of diarrhea. Kennels around the Abilene, Kansas, area were contacted and supplied with materials needed to collect a portion of the diet each day. With the onset of diarrhea, the kennels were instructed to ship the fecal material and diet from the previous 10 days to the laboratory for testing. Forty-one fecal samples and corresponding diets were screened for Salmonella, Clostridium perfringens, Campylobacter jejuni, Staphylococcus aureus, Staphylococcus intermedius, and pathogenic (piliated) Escherichia coli by direct culture using standard procedures. The fecal material was also screened for coronavirus and parvovirus using electron microscopy. Thirty-five "normal" fecal samples were screened for all of the above mentioned microorganisms as a control. In addition, the fecal material was screened for E. coli verotoxins I and II and clostridial enterotoxins. A total of 61 Salmonella isolates were recovered from the 41 samples of feces and diet submitted for testing; 31 were recovered from the feces and 30 from the diet. Four Salmonella isolates were recovered from the normal fecal samples. Results obtained by PCR, plasmid profiles, antigenic analysis, and antibiogram profiles indicated that 16 of the 31 isolates recovered from the fecal material were the same strain as that recovered from the diet. 相似文献
108.
Droll Jason A.; Hayhoe Mary M.; Triesch Jochen; Sullivan Brian T. 《Canadian Metallurgical Quarterly》2005,31(6):1416
Attention and working memory limitations set strict limits on visual representations, yet researchers have little appreciation of how these limits constrain the acquisition of information in ongoing visually guided behavior. Subjects performed a brick sorting task in a virtual environment. A change was made to 1 of the features of the brick being held on about 10% of trials. Rates of change detection for feature changes were generally low and depended on the pick-up and put-down relevance of the feature to the sorting task. Subjects' sorting decision suggests that changes may be missed because of a failure to update the changed feature. The authors also explore how hand and eye behavior are coordinated for strategic acquisition and storage of visual information throughout the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
TL Raymond WE Connor DS Lin S Warner MM Fry SL Connor 《Canadian Metallurgical Quarterly》1977,60(6):1429-1437
To identify any metabolic effects of dietary fiber upon cholesterol metabolism in man, six adult volunteer subjects were fed eucaloric cholesterol-free formula diets, with and without added dietary fiber for two 4-wk periods. A large quantity of dietary fiber was fed, some 60 g of plant cell wall material (or 16 g of crude fiber) derived from corn, beans, bran, pectin, and purified cellulose. This provided about five times the fiber intake of the typical American diet. The addition of fiber to the cholesterol-free diet did not change either the plasma cholesterol level (171+/-21 mg/dl, SEM, to 167+/-18) or the triglyceride (103+/-39 to 93+/-27 mg/dl). The excretion of both endogenous neutral steroids and bile acids were unchanged with fiber (505+/-41 to 636+/-75 mg/day and 194+/-23 to 266+/-47 mg/day, respectively.) However, total fecal steroid excretion was increased 699+/-29 to 902+/-64 mg/day, P < 0.025). With fiber, intestinal transit time was decreased (59+/-9 to 35+/-8 h, P < 0.005), and both the wet and dry stool weights were greatly increased.A second group of six subjects was fed similar diets containing 1,000 mg cholesterol derived from egg yolk. The addition of fiber to the 1,000-mg cholesterol diet did not alter either plasma cholesterol level (233+/-26 to 223+/-36 mg/dl) or triglyceride (102+/-19 to 83+/-11 mg/dl). The excretion of endogenous neutral steroids (618+/-84 to 571+/-59 mg/day), of bile acids (423+/-122 to 401+/-89 mg/day), and of total fecal steroids (1,041+/-175 to 972+/-111 mg/day) were unchanged by fiber. The absorption of dietary cholesterol was not altered when fiber was added to the 1,000-mg cholesterol diet (44.0+/-3.3 to 42.9+/-2.5%). A two-way analysis of variance utilizing both groups of subjects indicated a significant (P < 0.001) effect of dietary cholesterol upon the plasma cholesterol concentration. We concluded that a large quantity of dietary fiber from diverse sources had little or no effect upon the plasma lipids and sterol balance in man in spite of the fact that intestinal transit time and stool bulk changed greatly. 相似文献
110.
MM Guner 《Canadian Metallurgical Quarterly》1977,77(9):1300-1302
The results of hemoglobin determination in the CSF by the method of fluorescence microscopy in 195 patients speaks in favor of relative diagnostical importance of hemoglobin in the supra fall-out CSF for establishing the character of the stroke. The following circumstances testify to this fact: 1) in an artificial admixture of blood in the CSF in some cases there may be hemolysis of "passing" erythrocytes; 2) in a genuine admixture of blood, tests of hemoglobin in the centrifugate of the CSF may be negative since in some cases the transition of hemoglobin into bilirubin in the subarachmoid space occurs more rapidly than the hemolysis of erythrocytes. Thus, the hemoglobin does not accumulate in the liquid in quantities, sufficient enough to be measured by the existing methods; 3) in a large amount of artificial blood admixture, even without a hemolysis of "passing" erythrocytes the hemoglobin tests in the centrifugate of the CSF may be positive at the expense of hemoglobin of the blood plasma. 相似文献