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41.
42.
Extracellular single unit recording and microiontophoretic techniques were used to determine the sensitivities and interactions of D1 and D2 dopamine (DA) receptors in the caudate putamen (CPu) of rats that were denervated of DA by intraventricular injections of the catecholamine neurotoxin 6-hydroxydopamine (6-OHDA). Seven to 10 d after the 6-OHDA injection, DA levels in the ipsilateral CPu were reduced to 11.8% of control. Current-response curves revealed that the inhibitory responses of CPu neurons to microiontophoretic administration of both the selective D1 receptor agonist SKF-38393 and the selective D2 receptor agonist quinpirole were significantly increased in 6-OHDA-pretreated rats, suggesting up-regulation of both receptor subtypes. Although our previous studies have established that D1 receptor activation is normally required for (enables) the inhibitory effects of selective D2 agonists in the CPu, this requirement was no longer evident in 6-OHDA-denervated rats. Whereas acute DA depletion [produced by the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine (AMPT)] attenuated the inhibitory effects of quinpirole on CPu neurons, long-term DA denervation (produced by 6-OHDA) enhanced the inhibitory effects of the D2 agonist. The enhanced effects of quinpirole in 6-OHDA-lesioned rats were not due to residual DA stimulating supersensitive D1 receptors (i.e., enabling) since further DA depletion (99.7%), produced by acute administration of AMPT in 6-OHDA-lesioned rats, failed to diminish the inhibitory efficacy of quinpirole. In addition to relieving D2 receptors from the need for D1 receptor-mediated enabling, 6-OHDA lesions also abolished the normal synergistic relationship between the receptor subtypes since low (subinhibitory) currents of SKF-38393 (4 nA) failed to potentiate the inhibitory effects of quinpirole on CPu neurons in lesioned rats. Similar findings (i.e., supersensitivity and loss of synergistic effects) were obtained from rats that had received repeated pretreatment with reserpine (2.5 mg/kg) for 4 d, indicating that these effects of 6-OHDA lesions were due to the depletion of synaptic DA rather than to the structural loss of DA terminals. Therefore, both the quantitative (potentiation) and the qualitative (enabling) synergistic effects between D1 and D2 receptors in the rat CPu were abolished when these receptors were functionally supersensitive. The present study provides electrophysiological support for previous behavioral studies indicating that the requirement of D1 receptor stimulation for D2 receptor-mediated functional effects (enabling) is not maintained in rats chronically depleted of DA by either 6-OHDA lesions or repeated reserpine. 相似文献
43.
Dan Miron Sharon Brosilow Klari Felszer Dan Reich David Halle Daniel Wachtel Arthur I Eidelman Yechiel Schlesinger 《Journal of perinatology》2005,25(5):299-303
OBJECTIVES: To determine the incidence and clinical manifestations of human breast milk (HMB)-associated acquired cytomegalovirus (CMV) infection in small premature infants. STUDY DESIGN: A prospective study of premature infants born at or prior to 32 weeks gestation, and or infants weighing 1500 g or less at birth. The babies were divided into two groups: Group 1 included babies of CMV seropositive mothers who received HBM throughout the study period. Group 2 included babies of seronegative mothers or babies that did not receive HBM at all. Urine sample were obtained once weekly from birth until the age of 8 weeks or until discharge and were tested for the presence of CMV-DNA by PCR. RESULTS: Four of 70 infants from group 1 (5.7%, 95% CI, 0 to 11%) acquired CMV infection between the ages of 3 and 7 weeks as compared to none of 26 babies in group 2. Only one infected baby had severe CMV disease with complete recovery. CONCLUSION: The relative incidence of HBM-associated CMV infection and the severity of HBM-associated CMV disease in premature infants are low. 相似文献
44.
Differences in microbicidal activities of human macrophages against Toxoplasma gondii and Trypanosoma cruzi. 总被引:2,自引:1,他引:1
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D M Israelski F G Araujo J S Wachtel L Heinrichs J S Remington 《Infection and immunity》1990,58(1):263-265
The microbicidal activities of normal human pelvic macrophages against infection by the intracellular protozoa Toxoplasma gondii and Trypanosoma cruzi were examined. Macrophages allowed infection by T. gondii and yet possessed remarkable microbicidal activity against this organism. In contrast, human macrophages were not microbicidal against T. cruzi. 相似文献
45.
Eldo E. Frezza MD ; Cai Wei MD ; Mitchell S. Wachtel MD 《Journal of clinical hypertension (Greenwich, Conn.)》2009,11(5):284-288
Obesity is related to multiple comorbidities, including hypertension, diabetes, hypercholesterolemia, and sleep apnea. Comorbidities burden the health care system, such that in the United States, 6% to 8% of health care costs are related to obesity. Obesity-induced hypertension has multiple potential etiologic pathways, the most well established being increased renal sodium reabsorption with impaired pressure natriuresis via (1) activation of the renin-angiotensin system, (2) stimulation of the sympathetic nervous system, and (3) altered intrarenal physical forces. Weight loss is the best means to reduce obesity-related hypertension. For every 3 patients who lose 10 pounds of weight and maintain the weight loss for 4 years, 1 of them will eliminate the use of antihypertensive medication. Whereas nonsurgical therapy ineffectually treats extreme obesity, bariatric surgery yields durable weight loss, as well as resolution of some of the comorbidities associated with obesity, including hypertension. Increase in anti-inflammatory factors secreted by adipocytes may explain some of the improvement in blood pressure in the first 3 years post-procedure. Bariatric surgery safely and effectively improves and may improve or eliminate obesity-related hypertension. More data need to be collected to substantiate the same results over periods of time longer than 3 years. 相似文献
46.
Eldo E Frezza Audrae Barton Haleigh Herbert Mitchell S Wachtel 《Surgery for obesity and related diseases》2008,4(5):575-9; discussion 580
BACKGROUND: Sleeve gastrectomy (SG) has been shown to be an effective first-stage procedure for morbidly obese patients. The SG is presently performed over a bougie of varying sizes, which is useful, but known to produce injuries on insertion. In a retrospective study, we evaluated the effect of the laparoscopic SG (LSG) on excess weight loss during 1 year of follow-up using a 29F endoscope instead of a bougie. METHODS: During a 1-year period, LSG was performed on 20 (18 women and 2 men) consecutive patients. Gamma regression analysis was used to determine whether the variation in gender, age, initial body mass index, Hispanic ethnicity, and interval after surgery were related to excess weight loss. RESULTS: No deaths and 1 minor complication of oozing from the staple line occurred. The excess weight loss increased steadily over time, with a median 20% at 3 months, 32% at 6 months, 42% at 9 months, and 53% at 12 months. The median initial body mass index was 44.5 kg/m2, and the median age was 50 years. Of the 20 patients, 2 were men (10%) and 18 women (90%); 5 (25%) were Hispanic and 15 (75%) were non-Hispanic. The patients had a median 11.5 co-morbidities. Nausea was common for about 7 days postoperatively. An increase in the initial body mass index and increased co-morbidities were the only 2 variables directly and statistically connected with the percentage of excess weight loss (P <.05). CONCLUSION: The results of our study have shown that LSG with endoscopic guidance appears safe and effective and could be tried using a larger set of patients as a single-stage operation. 相似文献
47.
T L Wachtel H A Frank J A Nielsen 《Burns : journal of the International Society for Burn Injuries》1987,13(1):1-6
Modern intensive care is capable of keeping burned patients alive for substantial periods of time, despite burn severity with an 'unprecedented' or a marginal probability of survival. When the patient is initially judged to be that severely injured, or when, later in the course of the illness, a point is reached when further curative treatment is clearly futile (Civetta, 1981), the patient and/or the close relatives should be presented with the option of changing the treatment regimen from curative to comfort care. We (Frank and Wachtel, 1984) have described a process for reaching such decisions and a protocol for administering comfort care. During a 5-year period we offered this option to 24 patients. This paper reports the outcome in these cases. 相似文献
48.
H Wachtel 《International journal of pharmaceutics》2012,435(2):142-144
49.
Wachtel PL 《Psychotherapy (Chicago, Ill.)》2007,44(3):279-284
Carl Rogers' classic account (see record 2007-14639-002) of the necessary and sufficient conditions for therapeutic personality change is examined in light of developments in theory and practice since the time he wrote. Rogers' ideas, which diverged from and were very largely a challenge to, the dominant psychoanalytic ideology of the era in which he wrote, are considered in relation to new theoretical developments in what has come to be called relational psychoanalysis. They are also considered in light of the greatly increased influence of and substantial evidence supporting behavioral and cognitive-behavioral approaches. Points of convergence and divergence among these approaches are examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved). 相似文献
50.
Intraabdominal hypertension and the abdominal compartment syndrome are known to deleteriously affect a wide array of organ
systems. We retrospectively reviewed 62 women who underwent either laparoscopic gastric bypass surgery or adjustable gastric
banding. Their age, body mass index (BMI), and race were known. Their opening abdominal pressure was recorded by connecting
a Verress needle to a pressure monitor. Linear regression was used to assess the contribution of age, race, and BMI to the
observed variation in opening abdominal pressure. Neither variation in age or race explained the variation in opening pressure
(P > .05). By contrast, variation in BMI explained 8% of the observed variation in opening pressure (P < .05). For every 1 kg/mm2 increase in BMI, there was on average a 0.07 mm Hg increase in opening pressure. Increases in BMI are associated with increases
in intraabdominal pressure. 相似文献