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1.
Percutaneous transluminal coronary angioplasty (PTCA) of heavily calcified rigid coronary arteries has decreased success and increased complication rates. Three cases are presented describing a new technique for the dilatation of severely calcified coronary arteries that were not dilatable by conventional angioplasty methods. This technique involves the use of a balloon dilatation catheter system parallel to a guide wire. © 1993 Wiley-Liss, Inc.  相似文献   
2.
A patent foramen ovale (PFO) is an embryological remnant found in 27% of adults. It is a potential right-to-left intracardiac shunt. Shunting may be the result of reversal in the interatrial pressure gradient or abnormal streaming of blood in the right atrium. The pathologic consequences of right-to-left shunting include hypoxemia and paradoxical embolism. PFO may exacerbate preexisting hypoxemia or be its primary cause. Paradoxical embolism through a PFO is well documented. Its role in cryptogenic stroke remains controversial. A PFO may be detected by both invasive and noninvasive techniques. Contrast transesophageal echocardiography with provocative maneuvers is the diagnostic method of choice allowing visualization of the shunt. Patients with cryptogenic stroke should be screened for a PFO. If detected, noninvasive studies for deep vein thrombosis are recommended. Treatment must be tailored to the presentation. Surgical or transcatheter closure is recommended for hypoxemia. Prevention of venous embolism (air or thrombus) with or without closure of the PFO is recommended for paradoxical embolism.  相似文献   
3.
Postprandial hyperglycemia in diabetic patients can be modified by delaying the digestion and/or absorption of dietary carbohydrates. We have studied an orally active α-glucosidase inhibitor, Bay 1099, in normal volunteers to determine whether these inhibitors can decrease postprandial rises in serum glucose without causing gastrointestinal symptoms or significant fecal caloric wastage. Six subjects were given 25, 50, or 100 mg of Bay 1099 or placebo before meals for 1 week, each with a 1-week washout period. Fasting and postprandial concentrations of glucose, insulin, glucagon, enteroglucagon, and gastrointestinal inhibitory peptide (GIP) were measured after the first and last dose of Bay 1099, and the fecal excretions of protein, fat, fiber, and total calories were measured on the last three days of each diet. The passage of unabsorbed carbohydrate into the colon was determined by breath hydrogen analysis three times during each study week. Increasing doses of Bay 1099 were found to decrease the postprandial rise in serum glucose concentration, delay the time to peak insulin concentration, and decrease the output of GIP after the meal. No adaptation was apparent after 1 week of therapy. A dose of inhibitor (50 mg tid), which greatly improves postprandial glucose and hormone output in diabetes, was associated with minimal symptoms and no excess fecal caloric losses. Thus, glucosidase inhibitors such as Bay 1099 may be useful in the management of patients with carbohydrate intolerance.  相似文献   
4.
5.
The authors assessed the impact of the Nazi Holocaust on the course and symptoms of posttraumatic stress disorder (PTSD) among Israeli combat stress reaction casualties. They examined a sample of 96 such casualties of the 1982 Lebanon War whose parents had gone through the Nazi Holocaust and compared them to casualties who did not have such family history for 3 consecutive years beginning 1 year after their participation in the war. Results showed that 2 and 3 years after their participation in the 1982 Lebanon War, the children of Holocaust survivors, i.e., "second-generation" casualties, had higher rates of PTSD than did the control subjects, as well as a somewhat different clinical picture. Clinical and methodological implications of the findings are discussed.  相似文献   
6.
Longitudinal data were used to investigate whether anxiety, depressive, disruptive, personality, or substance use disorders are associated with risk for the development of eating disorders during adolescence or early adulthood. Psychiatric disorders were assessed among 726 youths from a random community sample during adolescence and early adulthood. Depressive disorders during early adolescence were associated with elevated risk for the onset of eating disorders, dietary restriction, purging behavior, and recurrent weight fluctuations after preexisting eating problems and other psychiatric disorders were controlled statistically. Disruptive and personality disorders were independently associated with elevated risk for specific eating or weight problems. The present findings suggest that depressive disorders during early adolescence may contribute to the development of eating disorders during middle adolescence or early adulthood.  相似文献   
7.
Muscularity, or the proportion of adipose tissue‐free body mass (ATFM) as skeletal muscle (SM), provides valuable body composition information, especially for age‐related SM loss (i.e., sarcopenia). Limited data from elderly cadavers suggest a relatively constant SM/ATFM ratio, 0.540 ± 0.046 for men (mean ± SD, n = 6) and 0.489 ± 0.049 for women (n = 7). The aim of the present study was to examine the magnitude and constancy of the SM/ATFM ratio in healthy adults. Whole‐body SM and ATFM were measured using multi‐scan magnetic resonance imaging. The SM/ATFM ratio was 0.528 ± 0.036 for men (n = 139) and 0.473 ± 0.037 for women (n = 165). Multiple regression analysis indicated that the SM/ATFM ratio was significantly influenced by sex, age, body weight, and race. The four factors explained 50% of the observed between individual variation in the SM/ATFM ratio. After adjusting for age, body weight, and race, men had a larger SM/ATFM ratio than women. Both older men and women had a lower SM/ATFM ratio than younger subjects, although the relative reduction was greater in men. After adjustment for sex, age, and body weight, there were no significant differences in the SM/ATFM ratios between Asian, Caucasian, and Hispanic subjects. In contrast, African‐American subjects had a significantly greater SM/ATFM ratio than subjects in the other three groups. In addition, the SM/ATFM ratio was significantly lower in AIDS patients than corresponding values in healthy subjects. Am. J. Hum. Biol. 13:612–619, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
8.
The microsporidium Enterocytozoon bieneusi is closely linked to wasting and diarrhea in a high proportion of individuals with AIDS. However, its relative contribution to disease is uncertain because diagnosis until recently depended on procedures involving endoscopy. A sensitive PCR technique which amplifies a fragment of the small-subunit rRNA gene of E. bieneusi from formalin-fixed stool samples was developed. Of 80 formalin-fixed stool samples collected from 74 Zimbabweans and 6 U.S. patients who were human immunodeficiency virus positive, 50% tested positive for E. bieneusi by PCR, whereas 24% tested positive for E. bieneusi by light microscopy of trichrome-stained fecal smears. In addition, we describe an in situ hybridization technique which detected and identified E. bieneusi as the causative agent in all six intestinal biopsy specimens tested. Both the PCR and in situ hybridization procedures are sensitive diagnostic tools which will complement currently available techniques and enable the differentiation of E. bieneusi from other microsporidia to be made.  相似文献   
9.
HIV-associated wasting is defined as > or = 10% involuntary weight loss and includes declines in both lean and fat mass. This large (757 subjects), randomized, double-blind, placebo-controlled trial investigated the efficacy, safety, and tolerability of recombinant human growth hormone (rhGH) in 2 doses-0.1 mg/kg up to a maximum of 6 mg daily (DD) or alternate days (AD)-in the treatment of wasting and weight loss in highly active antiretroviral therapy (HAART)-treated HIV-infected subjects. The evaluable population for ergometry comprised 555 subjects, 87.6% of whom were receiving HAART. At 12 weeks, median maximum work output increased by 2.4 and 2.6 kJ in the AD and DD groups, respectively. The median treatment difference was 2.9 kJ for DD vs. placebo (P < 0.0001). Body weight increased by 2.2 and 2.9 kg in the AD and DD groups, respectively. Corresponding median treatment differences vs. placebo were 1.5 and 2.2 kg (P < 0.0001). Lean body mass (LBM), by bioelectric impedance spectroscopy, increased by 3.3 and 5.2 kg, respectively (P < 0.0001 vs. placebo; P = 0.0173 DD vs. AD), and fat mass, predominately truncal, decreased. Quality of life (QoL) improved significantly in both rhGH groups. Fluid-retention adverse effects and hyperglycemia were more common in the DD than in the AD group. No significant changes in HIV viral load or CD4 cell count occurred. In conclusion, over the 12-week course of therapy, rhGH, 0.1 mg/kg DD, was superior to placebo in improving physical function, body weight, body composition, and QoL and was superior to AD dosing in restoring LBM.  相似文献   
10.
Alterations in regional fat, often associated with abnormalities in lipid and insulin metabolism, have been reported in HIV-infected adults. To determine whether similar abnormalities occur in children with HIV, patterns of change in regional body fat distribution were determined by dual energy x-ray absorptiometry in 28 prepubertal HIV-infected children. Eight (29%) children experienced lipodystrophy (LD), defined as extremity lipoatrophy together with trunk fat accumulation. Despite a mean body weight increase of 2.9 +/- 2.4 kg, children with LD experienced a mean loss of total fat in contrast to children without LD who increased total fat (-0.151 +/- 0.324 versus 0.981 +/- 1.041 kg; p <.01). Children with LD had significantly higher levels of HIV RNA and lower CD4 count and percentage at baseline. LD was associated with use of protease inhibitors or stavudine, (odds ratio [OR], 7.0, 95% confidence interval [CI], 1.1-45.2, p =.04; OR, 9.0, 95% CI, 1.4-59.8, p =.03, respectively). This observational study suggests that during a time in childhood when accumulation of extremity and trunk fat is expected, some HIV-infected children experience changes in fat distribution that are similar to HIV-associated LD reported in adults. Studies to determine whether HIV-infected children with changes in regional fat also experience increases in "atherogenic" lipids and insulin resistance as described in adults with HIV-associated LD are warranted.  相似文献   
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