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61.
Honeybee venom hyaluronidase (Api m 2) is a major glycoprotein allergen. Previous studies have indicated that recombinant Api m 2 expressed in insect cells has enzyme activity and IgE binding comparable with that of native Api m 2. In contrast, Api m 2 expressed in Escherichia coli does not. In this study, we characterized the carbohydrate side chains of Api m 2 expressed in insect cells, and compared our data with the established carbohydrate structure of native Api m 2. We assessed both the monosaccharide and the oligosaccharide content of recombinant Api m 2 using fluorophore-assisted carbohydrate electrophoresis and HPLC. To identify the amino acid residues at which glycosylation occurs, we digested recombinant Api m 2 with endoproteinase Glu-C and identified the fragments that contained carbohydrate by specific staining. Recombinant Api m 2 expressed in insect cells contains N-acetylglucosamine, mannose, and fucose, as well as trace amounts of glucose and galactose, and the oligosaccharide analysis is consistent with heterogeneous oligosaccharide chains consisting of two to seven monosaccharides. No sialic acid or N-acetylgalactosamine were detected. These results are similar to published data for native Api m 2, although some monosaccharide components appear to be absent in the recombinant protein. Analysis of proteolytic digests indicates that of the four candidate N-glycosylation sites, carbohydrate chains are attached at asparagines 115 and 263. Recombinant Api m 2 expressed in insect cells has enzymic activity and IgE binding comparable with the native protein, and its carbohydrate composition is very similar.  相似文献   
62.
Decompressive hemicraniectomy as an appropriate treatment for malignant middle cerebral artery (MCA) infarction is still a controversial issue. This study aimed to determine the survival rate and functional outcome, and factors associated with these, in patients with malignant MCA infarction. From January 2000 to December 2003, 60 patients with malignant MCA infarction were treated in our hospital. All patients in the study underwent a large ipsilateral craniectomy and duroplasty for decompression. The infarction territory was evaluated by either diffusion weighted magnetic resonance imaging or computed tomography. Clinical neurological presentation was evaluated using the Glasgow Coma Scale. Functional outcome was evaluated using the Barthel index (BI) and the Glasgow Outcome Scale (GOS) at follow-up 12 months later. Thirty-day mortality was 20% (12 patients) and 12-month mortality was 26.6%. The factors associated with higher mortality were age>or=60 years, involvement of more than one vascular territory, presence of signs indicating clinical herniation before surgery, and treatment more than 24 hours after ictus. The mean GOS score was 3.3+/-1.7. The mean Barthel index was 65.1+/-40.1. Twenty-nine (65.9%) patients had a favourable outcome (BI>or=60). The factors associated with favourable outcome were age<60 years and treatment within 24 hours of ictus, before clinical signs of herniation were noted. Decompressive hemicraniectomy should be performed in patients younger than 60 years within 24 hours of ictus before clinical signs of herniation develop. Age, timing of surgery and clinical signs of herniation are prognostic factors for mortality and functional outcome.  相似文献   
63.
The author reviews the issue on whether Rett syndrome (RS) is a subtype of pervasive developmental disorders (PDDs). More than 200 articles of RS have been published in the last 10 years. Internal and external validities of RS have been established by several independent studies. There remains the question whether RS presents clinical features that meet the total criteria for PDDs. The available data seem to support the idea of classifying RS as a subtype of PDDs in the DSM-IV.The views expressed in this article are those of the author and do not represent the official positions of the DSM-IV Task Forces, Work Groups, or the American Psychiatric Association.  相似文献   
64.
Sympathetic skin response (SSR) and R–R interval variation (RRIV) were studied in 36 chronic, nondiabetic uremics to compare with their nerve conduction studies (NCS) and clinical dysautonomia. Abnormal SSR was noted in 5 (13.9%) patients, abnormal RRIV in 14 (38.9%), and abnormal NCS in 26 (72.2%). The patients were classified into three groups: group (GP) 1: “normal,” n = 21 (58.3%), normal RRIV and SSR; GP 2: “isolated parasympathetic dysfunction,” n = 10 (27.8%), abnormal RRIV and normal SSR; and GP 3: “sympathetic sudomotor dysfunction,” n = 5 (13.9%), abnormal SSR. A significant difference in age was found among the three groups (GP 3 > GP 2 > GP 1; P < 0.0001, ANOVA). After controlling the age factor, we still noted a tendency toward increasing NCS disturbances (distal latency and nerve conduction velocity of peroneal nerve; P < 0.05, multiple regression analysis) and frequencies of clinical autonomic symptoms (postural dizziness and impotence; P < 0.05, Mantel–Hanszel test) from GP 1 to GP 3. Patients with abnormal SSR (GP 3) displayed significantly higher frequencies of postural dizziness and impotence, indicating the relationship between an absence of SSR and clinical dysautonomia. © 1994 John Wiley & Sons, Inc.  相似文献   
65.
OBJECTIVE: To determine the frequency of mutations in the regulatory domain of the gap junction protein connexin 43 in patients with visceroatrial heterotaxy. DESIGN: Mutation screening of the terminal 200 base pairs of connexin43 gene coding sequence in a series of patients from tertiary care centres. PATIENTS: 48 patients with visceroatrial heterotaxy attending UK Regional Paediatric Cardiology Centres. RESULTS: No changes from the published connexin43 consensus sequence were found in any of the 48 patients studied. CONCLUSIONS: Germline mutations of the phosphorylation sites in teh regulatory domain of the connexin43 gene are rare in patients with visceroatrial heterotaxy.  相似文献   
66.
Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection.  相似文献   
67.
The medialis pedis flap (MPF) has been used for the reconstruction of soft-tissue defects in the hand since 1990. From January 1997 through January 2000, 19 patients (15 male, 4 female) with hand injuries underwent microsurgical MDF reconstruction at Chang Gung Memorial Hospital. There were finger injuries in 16 patients and palm defects in 3 patients. The mean patient age was 32.6 years (age range, 16-58 years). Flap size ranged from 4.5 x 2 cm to 7 x 6 cm (mean, 6 x 2.8 cm). Only one flap had partial loss. The donor site was closed primarily in 9 patients, and was closed using a split-thickness skin graft in 9 patients and a full-thickness skin graft in 1 patient. At a mean follow-up of 13 months, the protective sensation was 16 mm using the static two-point discrimination test and was 10 mm using the moving two-point discrimination test. Based on this retrospective study the authors conclude that (1) the MPF has the advantages of thin and glabrous skin, (2) the size of pedicle is compatible with the recipient vessel in the hand, (3) there is low donor site morbidity, and (4) achieving protective sensation is possible.  相似文献   
68.
To evaluate the catabolic effects of dexamethasone therapy on protein metabolism, amino acid concentrations and urinary 3-methylhistidine (3MH) were measured in 28 premature infants who were included in a double-blind controlled study using early dexamethasone therapy in the prevention of bronchopulmonary dysplasia. Fifteen infants received dexamethasone (0.5mg/kg/day i.v.) and 13 infants received normal saline as control. Heparinized venous blood samples for amino acid analysis were obtained before the study and again at day 5 after starting the study. Urinary 3MH was measured on days 1, 3, 5, 7, 14, 21, and 28 of treatment. A substantial increase in amino acid concentrations was observed in infants receiving dexamethasone. Alanine, glutamine, citrulline, ornithine and cystine concentrations increased twofold or more. The 3MH:creatinine ratio was increased in the treated group. These metabolic effects were most likely due to an increase in protein catabolism.  相似文献   
69.
This review examines the evidence that a subset of patients with breast cancer have tumors that are stimulated to grow by host cells in the tumor stroma. The search for such a minority group was prompted by the following observations. Adjuvant chemotherapy which is immunosuppressive improves disease-free interval and survival, whereas non-specific immunostimulation worsens the prognosis. Intrinsic immune reactivity is associated with a poor prognosis. A subset of tumors with a bad prognosis has anaplastic cells, dermal lymphatic invasion and a moderate to intense lymphoplasmacytic stromal infiltrate. Evidence is reviewed that adjuvant chemotherapy may be beneficial by virtue of its immunosuppressive effects in addition to tumor kill of minimal residual disease.  相似文献   
70.
Vandellia cordifolia (COLSM) G. DON of Scrophulariaceae (V. cordifolia) is an annual wild herb indigenous to Taiwan. It can be found in plains, low altitudes, swampy places, and paddy fields. Taiwanese folk physicians use it in "nephritis, uremia, furnucle, carbuncle." The LD50 (95% confidence limit) of the crude extract of V. codifolia given by the oral route was more than 10 g/kg in rats. By the intraperitoneal route, it was 4.6 g/kg (4.35-4.93). The extraction rate was 16.6%. We studied its effects on renal functions and blood pressure and found that (1) it had diuretic effect on normal rats, (2) it decreased glomerular filtration rate and renal blood flow on normal kidneys in rabbits, (3) it had no effects on glomerular filtration rate and renal blood flow on glycerin-induced insufficient kidneys in rabbits, (4) it had diuretic effects on both normal and glycerin-induced insufficient kidneys in rabbits, (5) it could inhibit Na+ and K+ reabsorption on normal and glycerin-induced insufficient kidneys in rabbits, (6) it had hypertensive effect and this effect could be blocked by phenoxybenzamine. From the above facts, we conclude that V. cordifolia has diuretic effect and it may act on renal tubules to inhibit Na+ and K+ reabsorption.  相似文献   
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