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71.
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   
72.
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   
73.
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   
74.
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   
75.
76.
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   
77.
In some individuals, breathing is greater than at rest following voluntary hyperventilation. Most previous investigations have employed short hyperventilation periods; here we examine the time course of cardio-respiratory measures before, during, and after a 5-min voluntary hyperventilation, maintaining isocapnia throughout. We examined the possible co-involvement of the cardiovascular system; hypothesising that post-hyperventilation hyperpnoea results from an increase in autonomic arousal. In four subjects (two males, two females) of 18 (nine males, nine females) we observed a post-hyperventilation hyperpnoea, characterised by a slow decline of ventilation toward resting levels with a time constant of 109.0 +/- 16.1s. By contrast, heart rate, and systolic and diastolic blood pressure were unchanged from rest during and after voluntary hyperventilation for all subjects. We concluded that males and females were equally likely to exhibit post-hyperventilation hyperpnoea, and suggest that they may be characterised by an increased resting heart rate and the choice of breathing frequency to increase ventilation during the voluntary hyperventilation. We further concluded that post-hyperventilation hyperpnoea is rare, but when present is a strong and lasting phenomenon, and that it is not the result of an increased autonomic arousal.  相似文献   
78.
Techniques that reduce the toxicity of bacterial endotoxins are useful for studying the relationship between structure and biological activity. We used ionizing radiation to detoxify a highly refined endotoxin preparation. U.S. standard endotoxin EC. Dose-dependent changes occurred by exposure to 60Co-radiation in the physical properties and biological activities of the endotoxin. Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis showed gradual loss of the polysaccharide components (O-side chain and R-core) from the endotoxin molecules. In contrast, although endotoxin revealed a complex absorption pattern in the UV range, radiation treatment failed to modify that pattern. Dose-related destruction of the primary toxic component, lipid A, was suggested by the results of activity tests: both the pyrogenicity and limulus reactivity of the endotoxin were destroyed by increasing doses of radiation. The results indicate that the detoxification is probably due to multiple effects of the ionizing radiation on bacterial lipopolysaccharides, and the action involves (i) the destruction of polysaccharide moieties and possibly (ii) the alteration of lipid A component of the endotoxin molecule.  相似文献   
79.
We studied two families with an inherited deletion of the short arm of an X chromosome (Xp) in which affected male offspring have epiphyseal stippling in infancy (chondrodysplasia punctata), nasal hypoplasia, ichthyosis, and mental retardation. The presence of ichthyosis and the apparent pattern of X-linked recessive inheritance prompted investigation of the short arm of the X chromosome through studies of genetic markers and focused cytogenetic analysis. Biochemical studies suggested that there was a deletion of three genes previously mapped to the X-chromosome short arm, including the steroid sulfatase locus, the Xg locus, and the M1C2X locus. Prometaphase chromosomes demonstrated a deletion of Xp at p22.32 in the affected boys, in their obligate-carrier mothers, and in 11 of 25 women at risk as potential carriers. The women carrying the Xp deletion had normal gonadal function and fertility but were shorter than the noncarriers in their families (P less than 0.00001). These findings have implications for the genetic organization of this portion of the human X chromosome and demonstrate that small cytogenetic abnormalities may account for disorders with apparent mendelian patterns of inheritance.  相似文献   
80.
Humoral and cellular immune response after measles vaccination in Taiwan.   总被引:1,自引:0,他引:1  
Measles immunoglobulin G (IgG) seroepidemiologic studies have been widely used to monitor the effectiveness of measles immunization programs in Taiwan. However, studies about cellular immunity against the measles virus have been lacking. This study surveyed cellular immunity after measles, mumps and rubella combined vaccine (MMR) immunization in Taiwan. Seventy six people between 1 and 80 years of age were enrolled. All patients lived in northern Taiwan, and none of them had immunodeficient disease. Every enrolled patient donated a tube of heparinized blood between January 2004 and June 2004 for cross-sectional studies of IgG seroepidemiologic and MMR-specific lymphoproliferative response. The results showed that the current 3-dose (measles x 1 + MMR x 2) measles immunization program induced slightly higher IgG seroprevalence (100% vs 85%, p=0.244) and a higher frequency of significant (stimulation indices > or = 3) MMR-specific lymphoproliferative response (50% vs 15%, p=0.044) than a 2-dose (measles x 1 + MMR x 1) immunization program, although there was no difference in IgG titers and stimulation indices. Furthermore, the population aged older than 36 years (pre-immunization era) had higher IgG titers and seroprevalence, and similar MMR-specific lymphoproliferative responses to that of the population aged younger than 36 years (post-immunization era). In summary, with the limited data, the current 3-dose (measles x 1 + MMR x 2) measles immunization policy probably more effectively induces humoral and cellular immunity than the 2-dose (measles x 1 + MMR x 1) policy. Measles IgG seroprevalence in populations of different age groups exceeds nearly 90%. Measles has been eliminated temporarily in Taiwan. For a better understanding of the durability of vaccine-induced immunity and in order to establish the most appropriate immunization schedule, long-term and large-scale prospective studies of measles-specific seroepidemiology and cellular immunity will be needed.  相似文献   
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