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41.
PURPOSE: To investigate the role of technetium-99m (99mTc) tetrofosmin single-photon emission Computed Tomography (SPECT) associated with nitrate administration in the detection of hypoperfused but still viable myocardium in patients with chronic coronary artery disease and left ventricular (LV) dysfunction. MATERIAL AND METHODS: Twenty-two patients (mean age 54 +/- 11 years) with coronary artery disease, previous myocardial infarction and LV dysfunction (LV ejection fraction 38 +/- 13%) were examined. On different days all patients underwent 99mTc tetrofosmin (740 MBq) SPECT under control conditions at rest and after sublingual nitroglycerin administration (10 mg). Regional tetrofosmin activity was quantitatively measured in 22 myocardial segments per patient. In each segment, tracer uptake was expressed as a percentage of the region with the peak activity. RESULTS: Under control conditions, 267 myocardial segments (55%) showed normal tetrofosmin uptake (> 70% of peak activity), 107 segments (22%) showed a moderate reduction (51-70%) and 110 segments (23%) a severe reduction (< or = 50%) in tracer uptake. Among the 110 segments with a severe reduction in tetrofosmin uptake, 20 (18%) showed increased tracer uptake > or = 10% of after nitrate administration (from 44 +/- 5% to 58 +/- 3%, p < 0.0001). The remaining 90 (82%) segments with a severe reduction in tetrofosmin uptake did not show any change after nitroglycerin administration (from 38 +/- 9% to 39 +/- 8%, p = ns). CONCLUSIONS: In patients with chronic coronary artery disease and LV dysfunction, tetrofosmin cardiac SPECT associated with sublingual nitrate administration allows the detection of severely hypoperfused but still viable myocardium.  相似文献   
42.
We review the etiology and age incidence of precocious puberty in 438 girls examined between 1988-1998; 428 (97.7%) had central precocious puberty (CPP), the remaining 10 (2.3%) gonadotropin-independent precocious puberty (GIPP) of ovarian origin. The majority of CPP girls (59.6%) were aged between 7-7.9 yr, 22.4% were 6 year olds, and only 18% were under 6 years old. Cranial CT and/or MRI performed in 304/428 girls, showed neurogenic abnormalities in 56/304 (18.4%) CPP girls; 30 (9.9%) were due to previously diagnosed intracranial abnormalities and the remaining 26 (8.5%) were detected at the diagnosis of CPP. The frequency of neurogenic CPP tended to be higher in girls under 4 years of age while the frequency of idiopathic CPP tended to be higher in girls aged between 7-7.9 years, but no statistically significant differences were found. Interestingly, some CNS anomalies either of tumoral or congenital origin were detected at presentation in 7% of the girls aged over 7 years. Other related or coincidental clinical anomalies, mainly due to genetic diseases, were observed in 22/304 (7.2%) patients. History of precocious maternal menarche was found in 12/304 (4%) girls. In conclusion, idiopathic CPP was observed in 74% of the girls in this study. Neurogenic anomalies or other coincidental or related clinical findings were observed in the remaining 26%. The increased frequency of idiopathic CPP in girls aged over 7 years may suggest an early, but otherwise normal onset of puberty in many of these girls as a consequence of the trend towards earlier maturation. Nonetheless, the finding of CNS anomalies also in the older patients, raises the question of whether these patients should undergo a complete diagnostic work-up.  相似文献   
43.
Six children, originally regarded as being affected by prepubertal idiopathic growth failure, were found to have pituitary microadenomas. In all six patients, the growth failure (? 2 cm/yr) was the primary clinical sign, and was accompanied by a growth hormone deficiency that was discovered during the laboratory evaluation. Prominent alteration of the sella turcica was not demonstrated in the skull x-ray examinations of any of the children, even when the x-ray examinations were supplemented by hypocycloidal tomography. CT scanning proved to be a very useful integrating diagnostic procedure, revealing the adenoma to be a nodular area of increased density within the sella turcica. In all of the children, resumption of normal growth was obtained following the surgical removal of the tumor through a transsphenoidal approach.  相似文献   
44.
BACKGROUND: Clinical guidelines for smoking cessation may not be sufficient for helping some subgroups of smokers quit. Incorporating smoking cessation into home-based medical care can proactively reach high-risk smokers who may not have access to (or spontaneously seek) smoking cessation. METHOD: Home health care nurses (N = 98) were randomly assigned to deliver either Motivational Enhancement (ME; Motivational Interviewing + Carbon Monoxide Feedback) or Standard Care (AHCPR Guidelines for smoking cessation) to their patients. Seventy percent of patients were eligible and willing to participate (N = 273; 54% female, mean age = 57 years, 83% Caucasian, 41% < high school education). The study was conducted in Providence, RI, USA from 1998 to 2003. RESULTS: Biochemically verified continuous abstinence rates at the 12-month follow-up were 4.2% (SC) and 8.7% (ME) for intent to treat analyses, and 5.2% (SC) and 11.8% (ME) using all available cases (P > 0.05). ME reported more quit attempts and significantly greater reductions in the number of cigarettes smoked per day at all follow-ups through 12 months of post-treatment (all P values < 0.05). CONCLUSIONS: Use of an existing public health channel such as home health care to reach smokers who vary in their motivation to quit could have the potential for large public health impact.  相似文献   
45.
Our aim was to correlate the health status with objective and radiological outcomes in patients treated by open reduction and internal fixation for fractures of both bones of the forearm. We assessed 23 patients (24 fractures) subjectively, objectively and radiologically at a mean of 34 months (11 to 72). Subjective assessment used the disability of the arm, shoulder and hand (DASH) and musculoskeletal functional attachment (MFA) questionnaires. The range of movement of the forearm and wrist, grip and pinch strength were measured objectively and standardised radiographs were evaluated. In general, patients reported good overall function based on the DASH (mean 12; range 0 to 42) and MFA (mean 19; range 0 to 51) scores. However, pronation and grip and pinch strength were significantly decreased (p < 0.005). These deficiencies correlated with poorer subjective outcomes. Operative stabilisation of fractures of the radius and ulna led to a reliably acceptable functional outcome. However, despite these generally satisfactory results, the outcome scores worsened with reduction in the range of movement of the forearm and wrist.  相似文献   
46.
BACKGROUND: At the present time, the precise indications for laparoscopic surgery of adrenal incidentaloma (AI) have yet to be completely clarified. The most controversial issue is the role of laparoscopy in the treatment of potentially malignant and large adrenal masses. Trying to address these questions, we retrospectively examined a group of patients with AIs. MATERIALS AND METHODS: Forty-two patients with AIs who were laparoscopically treated since 1995 were enrolled in this study. The patients were divided into two groups: the 27 patients of the immediate surgery (IS) group were operated on immediately, whereas the 15 subjects in the delayed surgery (DS) group needed further evaluations and/or a follow-up period before surgery. Surgical timing for both groups was decided according to a widely accepted decision-making algorithm. Many outcome parameters of laparoscopy (operative time, blood loss, conversion rate, time to liquid and solid food nutrition, drainage removal, resumption of normal bowel habits, and average hospital stay) were analyzed in the two groups. The subjects had AIs of various sizes and different histotypes. RESULTS: Patients in the DS group had a higher risk for malignancy. The definitive pathology revealed a malignant biology in 26.6% of DS vs. 0% of IS cases. No difference in the outcome parameters of laparoscopy was observed between the two groups or among pathologically different AIs. A significant correlation was found between the operative time and the size of the AI (r=0.836, P<0.001, linear regression test). CONCLUSION: Our study shows that laparoscopy is feasible and safe for AIs, regardless of the preoperative probability of malignancy. The size of the AI was the only determinant for choosing a laparotomy. Further long-term studies are necessary to confirm the laparoscopic efficacy in terms of oncologic safety.  相似文献   
47.
Plasma levels of testosterone, androstenedione and oestradiol were determined in the spermatic venous blood of both testes of 17 patient affected by azoospermia due to tubular damage (Group I). The results were compared with those found in 5 patients affected by azoospermia of obstructive origin and 5 patients with an inguinal hernia (Group II). Mean spermatic levels of testosterone and androstenedione were not significantly different in the two groups, while the mean (+/- SE) oestradiol spermatic level was significantly higher in patients of Group I (5.02 +/- 0.75 nM/l vs. 2.20 +/- 0.365 nM/l; P less than 0.05). Moreover, while the testosterone/androstenedione and the androstenedione/oestradiol ratios were not significantly different in the two groups, the mean (+/- SE) testosterone/oestradiol ratio was significantly lower in patients of Group I (552.71 +/- 80.94 vs. 939.86 +/- 129.45; P less than 0.025). Peripheral testosterone and androstenedione mean levels were not significantly different between the two groups while the mean peripheral oestradiol level (+/- SE) was significantly higher in Group I (0.107 +/- 0.021 nM/l vs. 0.038 +/- 0.05 nM/l; P less than 0.025). Peripheral oestradiol was not significantly related to peripheral FSH, nor to spermatic oestradiol in both groups. These results suggest the possibility that oestradiol may be involved in the pathogenesis of some cases of male infertility.  相似文献   
48.
Motivational Interviewing (MI) has been established as an effective psychotherapeutic treatment for problem drinking in clinical settings. Consequently, there is a growing interest in applying MI to facilitate change across other health behaviors, such as tobacco use, eating habits, and physical activity in a variety of community-based research settings. These extended applications pose new challenges regarding implementation and evaluation. For instance, investigators must consider how best to train intervention counselors; implement strategies for preserving the MI spirit, despite limited client contact time; incorporate adjunctive strategies that support brief MI sessions; and develop a plan for monitoring and evaluating MI treatment fidelity. This article highlights specific examples of how several behavior change research projects applied MI across a variety of settings and populations, provides lessons learned from our experience as a collaborative workgroup, and offers strategies for consideration in future community-based research. Funding for this multisite project was provided by RO1 HL62165, 1AR01 45901, 5M01 RR00334, 1 R01 HD37368-01, 1 R01 DE13093-01, 1 R01 MH59594-01 We express our appreciation of the contributions made by the MI workgroup of the BCC, with specific assistance from Judy Salkeld. Special thanks go to Karen Emmons, Diane Elliot, Esther Moe, and Patricia Jordan who offered substantive comments and guidance on earlier drafts of this article.  相似文献   
49.
We studied the role of the dopamine D2 receptor in physiological regulation of pain-related behavior. The experiments were performed in dopamine D2 receptor knockout mice and in their wild-type controls. Baseline sensitivity to thermal nociception was determined by measuring the response latency in the hot plate at three different stimulus temperatures and by determining the radiant-heat-induced paw withdrawal. Mechanical sensitivity was assessed by determining paw withdrawal responses to stimulation with a calibrated series of monofilaments. Intracolonic capsaicin was used to produce sustained pain-related behavior and referred hypersensitivity to mechanical stimulation. The hot plate response latencies were not significantly different between the dopamine D2 receptor knockout and wild-type animals, although the stimulus temperature-dependent decrease in the response latency was steeper in the wild-type group. The radiant-heat-induced paw withdrawal latency was slightly longer in the knockout animals. The number of capsaicin-induced behavioral responses or the latency to the occurrence of the first capsaicin-induced response was not different between the experimental groups. Dopamine D2 receptor knockout animals were more sensitive to mechanical stimulation of the hindpaws than wild-type animals both in the baseline condition and following development of capsaicin-induced referred hypersensitivity in the hindpaws. The results indicate that dopamine D2 receptors influence baseline nociception in the mouse, although this effect is weak and submodality selective. Additionally, dopamine D2 receptors may contribute to attenuation of referred hypersensitivity caused by sustained nociception.  相似文献   
50.
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