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11.
Atrial natriuretic factor (ANF) is a peptide released from the heart in response to atrial distension. This peptide causes diuresis, vasodilatation, decreased blood pressure, and antagonizes the renin-aldosterone and antidiuretic hormone neuraxes. The influence of cardiopulmonary bypass and cardiac surgery on the circulation and release of ANF is unknown. Plasma ANF concentrations were therefore determined in patients undergoing coronary artery revascularization (CABG) and mitral valve replacement (MVR). Peptide levels were unchanged following anaesthetic induction. Plasma ANF concentrations decreased significantly during hypothermic (less than or equal to 28 degrees C) cardiopulmonary bypass in both patient groups. After 60 minutes of cardiac bypass, ANF declined from (mean +/- SEM) 512 +/- 132 to 20 +/- 6 pg.ml-1 (P less than 0.05) during MVR, and from 178 +/- 41 to 110 +/- 48 pg.ml-1 during CABG (P less than 0.05). Rewarming during bypass was associated with an increase in ANF concentration in both groups. Heparin anticoagulation and protamine reversal had no effect on immunoreactive ANF levels. In patients undergoing CABG, there was a linear relationship between plasma ANF concentration (pg.ml-1) and right atrial pressure (mmHg) prior to cardiopulmonary bypass (r = 0.86, P less than 0.005). However, one and three hours after cardiopulmonary bypass there was no significant relationship between right atrial pressure and ANF plasma levels. These results suggest that reduction in plasma ANF concentration occurs during hypothermic cardiopulmonary bypass. Furthermore, the proportional relationship between atrial distension and circulating ANF concentration was altered following cardiac surgery.  相似文献   
12.
13.
The presentation aims to examine the criteria of quality for care and education programmes for young disabled children in integrated early childhood settings. The conceptual and practical issues which influence quality programmes will be discussed with particular reference to the Integration Programmes operated throughout South Australia in early childhood centres.

The Integration Programmes, developed to enable and support the integrated or normalised development of young children has as its specific 'target' group individual children who are 'too delayed or disabled' to be able to fully participate or participate without direct assistance in community based early childhood programmes. Some of these children are extremely disabled and others' handicapping conditions are exacerbated by severe lack of other available community resources, isolation and other factors.

Integration is more than 'being there'—it is a complex process based upon the recognition of human value and human rights. For greater insight into the Integration Programmes an appraisal of the following aspects will be provided.

• the principles of integration

• the goals of integration

• the dimensions of integration.

The dimensions of integration will be placed in relation to the indicators of quality in early childhood programmes. The juxtaposing of these parameters of quality will lead to the emergence of guidelines for practical goalsetting and evaluation hallmarks of excellence in integration.  相似文献   
14.
Liver blood flow after major hepatic resection   总被引:1,自引:0,他引:1  
The factors involved in liver regeneration are poorly understood, but it has been suggested that blood flow plays a role. This paper documents the changes in liver blood flow (LBF) that occur after major hepatic resection. Eight patients, ranging in age from 37 to 76 years, underwent liver resection. Liver blood flow was measured preoperatively and on days 1, 4 and 7 postoperatively by low-dose galactose clearance. There was a significant (p less than 0.01) fall in LBF on day 1 compared with the baseline value, followed by a significant (p less than 0.01) rise from the baseline value by day 4. By day 7, LBF had returned to baseline levels and was significantly (p less than 0.01) lower than on day 4. These changes in LBF may be related to the stimulus for liver regeneration and increased functional demands during the early regenerative phase.  相似文献   
15.
A randomized, double-blind, placebo-controlled study was performed to assess the analgesic efficacy of intramuscular nefopam hydrochloride after upper abdominal surgery. Patients received either 20 mg nefopam (n = 23) or matching placebo (n = 26), 90 min before surgery, immediately after surgery, and 6, 12 and 18 h after the end of surgery. The 24-h morphine requirements were measured using a patient-controlled analgesia system delivering on-demand intravenous bolus doses of morphine. Pain was assessed using visual analogue scales. Patients receiving nefopam had a mean (+/- s.e.m.) cumulative morphine consumption of 4.1 +/- 0.8 mg in the first hour, compared with 8.5 +/- 0.8 mg in the control group (P less than 0.01). After 24 h the consumptions were 44.1 +/- 7.2 mg and 62.5 +/- 6.9 mg respectively (P less than 0.05). The pain scores in both groups were similar. This study confirms that nefopam hydrochloride has significant analgesic effects and would be a useful supplement to morphine in the management of postoperative pain.  相似文献   
16.
The stroma of fibroadenoma and phyllodes tumor usually consists of fibroblastic proliferation. Rarely the stroma contains bundles of smooth muscle. Pseudoangiomatous hyperplasia of the mammary stroma has been described in fibroadenomas. However, true benign vascular stroma has not been reported. We report a case of a 34-year-old Chinese woman who presented with a large mass occupying the entire left breast. Left mastectomy was performed and showed a large, well-circumscribed, lobulated, rubbery-firm tumor measuring 13 x 10 x 6 cm. Microscopic examination revealed a fibroepithelial tumor formed by an organoid pattern of ductal structures with a very striking stromal appearance composed of extensive vascular proliferation and that demonstrated strong immunoreactivity for CD31, CD34, and Factor VIII. Ultrastructural examination revealed intercellular junctions, basal lamina, pinocytotic vesicles, and Weibel-Palade bodies in the cells lining the vascular spaces, confirming their endothelial nature. These findings rule out the diagnosis of pseudoangiomatous hyperplasia. The patient developed local recurrence a year later, and the resection showed malignant phyllodes tumor with ductal carcinoma in situ.The extensive vascular stroma noted in the primary tumor may have played a role in the malignant transformation of the epithelial and stromal components in this tumor.  相似文献   
17.
Carbonic anhydrase (CA) inhibitors, such as acetazolamide (AZ), formerly used as diuretics, still play a role in the treatment of glaucoma, epilepsy, and altitude sickness. There is now hard evidence from both in vitro and in vivo studies in animals that carbonic anhydrase plays a vital function in bone loss. Acetazolamide blocks bone resorption in these experimental models. We have postulated that acetazolamide has potential for the treatment of human conditions associated with bone loss. In preparation for a clinical trial of acetazolamide's effectiveness in this regard, we developed an enzymatic method for determining the total concentration of acetazolamide in human serum. Acetazolamide is stripped from binding to serum proteins by adding 10(-6) M salicylic acid and adjusting the pH to 2.5, followed by ultrafiltration through a membrane (10 kD cutoff). The latter permits the free acetazolamide to enter the filtrate but retains any carbonic anhydrase (31 kD) which may contaminate the serum from hemolysis. The carbonic anhydrase inhibitory activity in the filtrate, representing the acetazolamide, is determined in a carbonic anhydrase assay using acetazolamide as the standard. Recoveries of acetazolamide added to human serum ranged from 83% to 94% depending on the concentration. Precision, as judged by the coefficient of variation, was 10.5%.  相似文献   
18.
19.
Lymphoma presenting as a salivary gland mass   总被引:2,自引:0,他引:2  
A retrospective review of 36 cases of lymphoma presenting as a salivary gland mass was conducted over a 34-year period. A significant increase in the occurrence of lymphoma was noted in proportion to other salivary gland tumors (P less than 0.01, chi 2 analysis: 1954-1972, 11 of 714 (1.5%); 1973-1979, 9 of 201 (4.5%); 1980-1987, 16 of 265 (6.0%). The mean age was 61 years, sex distribution was equal, and 75% occurred in the parotid. Only 42% presented with signs or symptoms other than a painless mass. Glandular excision was done in early stages of the disease while biopsy was done at later stages. Frozen section analysis was accurate in all but one case and was useful in determining if biopsy were adequate. All patients were definitively treated with chemotherapy and/or radiotherapy. Several instructive points are apparent. Any patient presenting with an isolated salivary gland mass can have a lymphoma. There has, in fact, been a significantly increasing proportion of salivary gland lymphoma among the various salivary gland tumors in our patient population. In contrast to other salivary gland tumors, surgery is reserved for diagnosis and not for treatment. A lymph node biopsy may be sufficient to establish a diagnosis, in which case, glandular excision is unnecessary. Most of the patients presented with an asymptomatic isolated salivary gland mass. The presence of adjacent adenopathy, a rubbery feel to the mass, and the intraoperative appearance were the most suggestive signs of lymphoma. Frozen section analysis is helpful in determining the appropriate extent of surgery and is recommended.  相似文献   
20.
The ratio of the length of the second and fourth digits (2D:4D), a putative proxy of prenatal testosterone (PT), is correlated with measures of physical fitness. The relationship between the organizing effect of PT on physical fitness is likely to arise as a response to intrasexual male competition for females. Physical strength is also likely to be important in intrasexual conflict, but nothing is known concerning the relationship between 2D:4D and strength. The strength of an individual is strongly influenced by body size, and 2D:4D is strongly dependent on ethnicity. We present evidence that strength, as measured from hand-grip strength, is related to 2D:4D in samples from two ethnic groups (52 Caucasian men from Germany, and 88 Oriental Mizos men from northeast India) which differed markedly in size. We found that 1) the German men were heavier and stronger, but had higher 2D:4D (lower PT) than the Mizos men; 2) a median split for grip strength into low (LGS) and high (HGS) groups showed that for right-hand 2D:4D (but not left-hand 2D:4D), the LGS men had higher 2D:4D than the HGS men; and 3) the relationships between right 2D:4D and grip strength were independent of ethnicity, age, height, and weight. Measures of grip strength correlate strongly with strength in other muscle groups, so we conclude that PT may have an early organizing effect on strength in men, and this is likely to be widespread in human groups.  相似文献   
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