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991.
Four ewes, each fitted with a rumen cannula and with catheters in the mesenteric artery and portal and mesenteric veins, received continuous intrarumen infusions of water or of short-chain fatty acids (SCFA). SCFA infusions were isoenergetic (83 kJ/h) and provided rumen molar proportions (acetate:propionate:butyrate) of 70:20:10, 50:40:10 or 50:20:30. The rumen SCFA production rate with the basal diet was 90.0, 23.1 and 8.8 mmol/h for acetate, propionate and butyrate respectively. Portal net fluxes indicated that 74, 67 and 22-30% of infused acetate, propionate and butyrate respectively, reached the portal vein. Portal net release of beta-hydroxybutyrate increased with SCFA infusions, irrespective of the amount of butyrate infused. Portal net release of lactate decreased with high-butyrate infusion. Portal net uptake of glucose increased with the SCFA infusions. In ewes infused with water, a portal net uptake of total amino acids (AA) was observed. SCFA infusions decreased the uptake of nonessential AA (glutamate, glycine, but not glutamine) and increased the net release of tyrosine and essential AA (isoleucine, leucine). Portal net fluxes of AA were similar with both high-acetate and high-propionate infusions. Lower net uptake of glutamine and net release of most essential AA and some nonessential AA were observed with the high-butyrate infusion. Energetic summation of portal net release was not significantly different between the three SCFA infusions, although it tended to be lower with high-butyrate infusion. This may be related to the higher trophic effect of butyrate on the digestive mucosa.  相似文献   
992.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
993.
This report highlights the association between tuberous sclerosis and Wolff-Parkinson-White syndrome. Ten patients with concurrent diagnoses of Wolff-Parkinson-White syndrome and tuberous sclerosis were identified. Wolff-Parkinson-White syndrome presented early in life, nine cases being diagnosed in the first year. Eight of the 10 cases were male. In eight cases, the syndrome was associated with supraventricular tachycardias, and in nine with cardiac rhabdomyomata. One child died from cardiac failure secondary to obstruction of the left ventricular outflow tract by a rhabdomyoma. Five of nine survivors showed resolution of Wolff-Parkinson-White syndrome on follow up. The accessory pathway was localised in nine patients from surface electrocardiograms: six children had left sided pathways and three had right sided pathways.  相似文献   
994.
995.
Purpose: Severe acute toxicity limits the effective use of radiotherapy in patients who are radiosensitive, and it is not usually possible to identify these radiohypersensitive (R-H) individuals before treatment commences. Five such R-H patients were detected over a 3-year period. We undertook this study to determine whether the severe acute radiohypersensitivity of these five individuals showed any correlation with cellular and molecular parameters known to be abnormal in radiosensitivity-related syndromes such as ataxia–telangiectasia (A-T).

Methods and Materials: Lymphoblastoid cells were isolated from fresh blood from the 5 R-H individuals who had previously demonstrated clinical R-H at least 9 months prior to sampling. Lymphoblastoid cell lines (LCLs) were established to determine the extent of postradiation chromosomal aberrations, cell cycle delay, cell proliferation, and tumor suppressor p53 protein stabilization. The polymerase chain reaction (PCR) and protein truncation (PTT) assays were used to test for the possibility of mutations in the gene mutated in A-T, termed ATM.

Results: LCLs derived from R-H subjects retained a significantly higher degree of radiation-induced chromosomal aberrations when compared to normal control LCLs. p53 stabilization by ionizing radiation appeared normal in all but one R-H subject. There was no evidence of A-T gene truncation mutations in any of the R-H subjects tested.

Conclusions: All R-H subjects in this study had their cellular radiosensitivity confirmed by the chromosomal aberration assay. Delayed p53 stabilization at 4 hours postirradiation in one R-H subject suggested that different etiologies may apply in the radiohypersensitivity investigated in this study.  相似文献   

996.
Purpose: To evaluate proteinuria occurring early after ifosfamide therapy and to assess the use of changes in proteinuria in the prediction of severe chronic nephrotoxicity. Methods: One-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis was used to characterize urine protein excretion in 12 children with solid tumours before and after the first course of ifosfamide treatment, and in 24 healthy children. Chronic nephrotoxicity was evaluated at 6 months after ifosfamide treatment and graded as none, mild, moderate or severe. Results: Urine from healthy children and from 10 of 12 patients before ifosfamide therapy showed a protein band with a molecular weight (95.4 kDa) corresponding to that of Tamm-Horsfall protein but no lower molecular weight proteins. After the first course of ifosfamide this 95.4-kDa protein was lost in six of ten patients with a concomitant appearance of a low molecular weight proteinuria (<70 kDa) in eight. Tamm-Horsfall protein was lost in two of five patients who subsequently developed no or mild nephrotoxicity and in four of five patients who subsequently developed moderate or severe nephrotoxicity. Conclusions: Early subclinical changes in urine protein excretion after ifosfamide, manifested by a loss of Tamm-Horsfall protein excretion, may be predictive of subsequent chronic nephrotoxicity. Received: 27 August 1996 / Accepted: 25 July 1997  相似文献   
997.
The expression of estrogen (ER) and progesterone (PgR) receptors was analyzed in a retrospective series of 3000 patients who had operable primary breast cancer. Patients were stratified according to ER and PgR status and the study was focused on the two groups (ER–PgR+ and ER–PgR–) of patients whose tumors contained low levels of ER (< 15 fmol/mg protein), regarding potential response to endocrine therapy. The comparison of clinical or histological characteristics between ER–PgR+ and ER–PgR– patients was analyzed as well as the disease-related death and survival. The mean follow-up was 86.3 months. Among the 529 ER–patients, 62 were PgR+ (12%), whereas 467 were PgR– (88%). The ER–PgR+ and ER–PgR– populations represented 2% and 15.6% of the overall population, respectively. In ER– tumors, the PgR status was significantly related to: age, menopausal status, tumor size, SBR grade, and histological type, but not to the type of surgical treatment or to lymph node involvement. ER–PgR+ tumors had smaller size (64% T1 vs 43%) (p=0.004) and were more frequently grade I (28% vs 12%) than ER–PgR– ones (p < 0.001). In addition, the patients with ER–PgR+ tumors were significantly younger (49.4 years vs 58.4 years; p < 0.0001), and were more frequently premenopausal (76% vs 36%; p < 0.001). The disease-free interval and the metastasis-free survival tended to be worse for ER–PgR– than for ER–PgR+ patients, but the difference was not statistically significant at 10 years. However, a small but significant difference in overall survival, in favor of the PgR+ group, was observed between the two groups during the first 5 years (p=0.03).We conclude that in combination with ER, PgR status defines a group of patients with clinical and biological specificity, which could be considered for specific endocrine therapy.  相似文献   
998.
Objective To use information collected by the Confidential Enquiry into Stillbirths and Deaths in Infancy to help obstetric, midwifery and paediatric practice in the management of shoulder dystocia.
Design Review of casenotes by a multidisciplinary focus group.
Sample All 56 cases reported to the Confidential Enquiry into Stillbirths and Deaths in Infancy from England, Wales and Northern Ireland in 1994 and 1995, where stillbirth or neonatal death was attributed to shoulder dystocia.
Main outcome measures Case notes were reviewed with respect to a range of perinatal variables. Comparisons were made with normative data from other studies when appropriate.
Results Maternal obesity and big babies were over-represented in pregnancies complicated by fatal shoulder dystocia. Fetal compromise was recorded in 26% of labours. The median time interval between delivery of the head and the rest of the body was only five minutes. The lead professional at the time the head was delivered was a midwife in 65% of cases. Middle grade or senior obstetric staff were supervising 47% of cases by the time the body was delivered.
Conclusions Antenatal prediction of shoulder dystocia is imprecise, and the majority of deliveries are attended by midwives. A relatively brief delay in delivery of the shoulders may be associated with a fatal outcome.  相似文献   
999.
Thirty-four consecutive women undergoing endometrial laser ablation, as a treatment of menorrhagia, were recruited to assess the validity of fluid absorption monitoring by a new continuous automated system (AquaSens). The same group of women also had monitoring of fluid absorption carried out by our standard technique of weighing. The intra-class correlation coefficient for the fluid deficit estimated by AquaSens compared to our standard technique of manually weighing the irrigation bags was 0.98 (95% CI 0.96–0.99). Aquasens therefore provides a valid and non-invasive method of continuously monitoring fluid deficit amongst patients undergoing operative hysteroscopy procedures, thereby reducing the risk of unexpected fluid absorption and its potentially fatal sequelae.  相似文献   
1000.
OBJECTIVE: To determine the impact of a hospital-coordinated discharge care plan, involving a multidisciplinary team of primary health care providers, on hospital length of stay, quality of life, and both patient and general practitioner inclusion in, and satisfaction with, discharge procedures. DESIGN: This investigation comprised a prospective, randomized, controlled, clinical trial. SETTING: This multicentre and cross-jurisdictional study focused on areas of tertiary and primary health care as well as community allied health in Western Australia. PARTICIPANTS: Patients (n = 189) with chronic cardiorespiratory diagnoses were recruited from respiratory, cardiovascular, and general medical wards at two tertiary hospitals. INTERVENTION: Subjects were randomly assigned to one of two groups. Intervention group patients received a discharge care plan in accordance with that outlined in the Australian Enhanced Primary Care Package, completed before discharge and sent to the patient's general practitioner and other community service providers for review. Control patients were discharged under existing hospital processes. Outcome measures. Patients and general practitioners were surveyed pre-discharge and 7 days post-discharge for quality of life and opinion of discharge procedures. Hospital length of stay was also determined. RESULTS: Significant improvements in discharge planning involvement, health service access, confidence with discharge procedures, and opinion of discharge based on previous experience were seen for patients who received the discharge care plan. Further, improved perceptions of mental quality of life were observed within the first week post-discharge for intervention patients. Length of stay showed no difference between groups. Extent and speed of hospital-general practitioner communication were significantly improved via the intervention. CONCLUSIONS: Our results indicate that a multidisciplinary discharge care plan, initiated before separation, improves quality of life, involvement, and satisfaction with discharge care, and hospital-general practitioner integration. As such, it possesses benefits over current Western Australian hospital discharge procedures for the care of chronically ill populations.  相似文献   
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