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81.
A 28-year-old woman presented with right shoulder pain and, after a delay, a diagnosis of clavicular stress fracture was made. The patient gave no history of repetitive abnormal loading of the upper limbs which could have assisted the diagnosis. The authors wish to raise awareness of this rare diagnosis such that it can be considered in the differential for shoulder pain of unclear origin.  相似文献   
82.
The classical literature on endocrine effect on voice considers oral contraceptives (OCs) as a risk factor for voice. However, recent studies revealed no adverse effect of new-generation OCs on voice. It was also suggested that OCs could improve specific voice characteristics via different mechanisms. The aim of the present study was to evaluate the effect of OCs on voices of women who use different formulations containing drospirenone (n=10), desogestrel (n=9) and gestodene (n=10). Acoustic voice measures of the 29 women were evaluated twice during the menstrual cycle. Fundamental frequency, frequency as well as amplitude stability and noise characteristics were measured using a computerized voice analysis program. Results indicated that vocal stability and quality were similar in the three groups tested. Marginal differences were observed between the drospirenone group and the other two groups. This preliminary observational study indicates that although drospirenone was previously shown to reduce water retention, this effect was not found to directly influence voice characteristics of women who use OCs.  相似文献   
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PURPOSE: The purpose of this study was to identify the characteristic features of omental infarction so that this entity can be differentiated from other acute conditions in the right lower quadrant of the abdomen. METHODS: A retrospective review was undertaken. We searched our hospital medical records and found 6 patients with the diagnosis of omental infarction in the last 3 years. Clinical, sonographic, and CT findings at the time of hospital admission and at follow-up were studied. RESULTS: In 5 of the 6 patients (83%) sonography demonstrated a moderately hyperechoic, noncompressible ovoid mass located in the omental fat between the umbilicus and the right colon corresponding to the point of maximal tenderness or to the site of a palpable lesion on physical examination. In 1 patient, sonography revealed no abnormalities. In all patients, the diagnosis of omental infarction was confirmed by CT. One patient underwent laparoscopy because of intractable pain; laparoscopy revealed a necrotic segment in the omentum, and pathologic analysis confirmed the original diagnosis. CONCLUSIONS: Omental infarction is a benign self-limited disease that can mimic acute abdomen. The diagnosis can be established preoperatively with sonography and CT, which may avoid unnecessary laparotomy.  相似文献   
85.
OBJECTIVE: Premature exposure of membranes used in guided bone regeneration (GBR) results in decreased bone formation. The effect of an expanded polytetrafluoroethylene (e-PTFE) and two collagen membrane on bone healing of buccal dehiscence defects around implants in cases with and without premature membrane exposure was clinically evaluated. METHODS: Three groups were established: Group OS (Ossix, n=73 implants, 41 patients), Group BG (Bio-Gide, n=53 implants, 28 patients) and Group GT (e-PTFE, Gore-Tex, n=34 implants, 17 patients). Defect height and width were measured at the time of implant placement and at second stage surgery. Surface area was calculated as half ellipses. When several implants were placed simultaneously, a mean of their defect width and height was calculated. RESULTS: Mean percentage reduction of defect area (92.2+/-13.78% Group OS, 94.6+/-6.69% Group BG, and 97.3+/-4.91% Group GT) and height (81.6+/-23.19%, 85.4+/-12.26%, and 93.4+/-9.39% respectively) did not show statistically significant differences between groups. Differences between groups were not statistically significant for all parameters when cases without spontaneous membrane exposure were compared. However, differences were significant when spontaneous membrane exposure occurred. Mean percentage reduction of defect area among cases where membrane exposure occurred was 91.5+/-10.86% Group OS, 71.5+/-8.61% Group BG, and 73.7+/-13.97% Group GT. Mean percentage reduction of defect height among cases with membrane exposure was 76.4+/-18.28%, 53.4+/-9.86%, and 49.4+/-11.05%, respectively. CONCLUSIONS: Premature exposure of membranes and subsequent and consequent exposure of implants results in impaired bone healing. Certain barrier membranes, as used in group OS, are apparently capable of supporting gingival healing even when prematurely exposed that could be advantageous in GBR procedures.  相似文献   
86.
BACKGROUND: The human haptoglobin (Hp) gene is polymorphic with two functional classes of alleles, denoted 1 and 2. We have demonstrated in three longitudinal studies and several cross-sectional studies that the Hp genotype is an independent risk factor for diabetic vascular disease. These studies have presented a compelling argument that diabetic individuals homozygous for the Hp 1 allele are at decreased risk of vascular complications as compared to diabetic individuals with the Hp 2 allele. METHODS: The naturally occurring (wild type) mouse Hp is a class 1 Hp allele. We examined renal hypertrophy in wild-type mice, Hp knockout mice (Hp 0), and in mice with the Hp 2 allele (Hp 2) with and without diabetes. RESULTS: In the absence of diabetes, we found that renal hypertrophy was significantly increased in Hp 0 mice and that this could be prevented with vitamin E. There was no difference between wild type and Hp 2 mice with regard to renal hypertrophy in the absence of diabetes. However, in the presence of diabetes, Hp 2 mice demonstrated a significant increase in renal hypertrophy as compared to wild-type mice. CONCLUSIONS: These results support a direct linkage between diabetic vascular disease and the Hp genotype. These Hp-modified mice may serve as a platform on which to test a variety of pharmacological agents in order to decrease diabetic vascular disease.  相似文献   
87.
The aim of the study was to directly compare the threshold electrical charge density of the retina (retinal threshold) in rabbits for the generation of electrical evoked potentials (EEP) by delivering electrical stimulation with a custom-made microelectrode array (MEA) implanted into either the subretinal or suprachoroidal space. Nine eyes of seven Dutch-belted rabbits were studied. The electroretinogram (ERG), visual evoked potentials (VEP) and EEP were recorded. Electrodes for the VEP and EEP were placed on the dura mater overlying the visual cortex. The EEP was recorded following electrical stimulation of the MEA placed either subretinally beneath the visual streak of the retina or in the suprachoroidal space in the rabbit eye. An ab externo approach was used for placement of the MEA. Liquid perfluorodecaline (PFCL; 0.4 ml) was placed within the vitreous cavity to flatten the neurosensory retina on the MEA after subretinal implantation. The retinal threshold for generation of an EEP was determined for each MEA placement by three consecutive measurements consisting of 100 computer-averaged recordings. Animals were sacrificed at the conclusion of the experiment and the eyes were enucleated for histological examination. The retinal threshold to generate an EEP was 9 +/- 7 nC (0.023 +/- 0.016 mC cm(-2)) within the subretinal space and 150 +/- 122 nC (0.375 +/- 0.306 mC cm(-2)) within the suprachoroidal space. Histology showed disruption of the outer retina with subretinal but not suprachoroidal placement. The retinal threshold to elicit an EEP is significantly lower with subretinal placement of the MEA compared to suprachoroidal placement (P < 0.05). The retinal threshold charge density with a subretinal MEA is well below the published charge limit of 1 mC cm(-2), which is the level below which chronic stimulation of the retina is considered necessary to avoid tissue damage (Shannon 1992 IEEE Trans. Biomed. Eng. 39 424-6).  相似文献   
88.
Environmental exposure has been linked to non-Hodgkin's lymphoma (NHL). Toxic volatile compounds were found in groundwater downstream of an industrial site in southern Israel. The risk of NHL and clinical characteristics of NHL patients were analyzed in relation to their proximity to the site.  相似文献   
89.
90.
OBJECTIVE: It is widely held that there is a delayed onset of antipsychotic action and that any early effects represent nonspecific behavioral effects. Recent research has shown that antipsychotic action begins within the first week. The authors tested the hypothesis that psychosis improves within the first 24 hours of antipsychotic treatment. METHOD: In this multicenter, double-blind, placebo-controlled study, 311 patients with a diagnosis of schizophrenia spectrum disorder and an acute exacerbation were randomly assigned to receive 10 mg i.m. of olanzapine, 7.5 mg i.m. of haloperidol, or intramuscular placebo. Subjects were rated with structured rating scales (Positive and Negative Syndrome Scale and Clinical Global Impression) at baseline, 2 hours, and 24 hours. RESULTS: The olanzapine and haloperidol groups showed greater resolution of overall symptoms than the placebo group; for the olanzapine group, this effect was evident at 2 hours. A factor analysis showed that an independent change in psychosis (which included conceptual disorganization, hallucinatory behavior, unusual thought content) was evident within the first 24 hours for both drugs. This improvement in core psychosis was not mediated unidirectionally by changes in nonspecific behavioral effects or other psychopathology. CONCLUSIONS: These data suggest that the onset of antipsychotic action is early and that the magnitude of this action grows with time. This clinical reality calls into question some prevailing hypotheses regarding the mechanism of action of antipsychotics and suggests that antipsychotic action may be more proximally related to the blockade of dopamine transmission than was originally thought.  相似文献   
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