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61.
Although penicillin still remains highly effective for syphilis, concerns have been raised that current regimens may be inadequate for the treatment of early syphilis. We report the failure of benzathine penicillin in the treatment of secondary syphilis. Extensive tracing of sexual contact history failed to identify sources of possible reinfection; therefore, we believe that this case represents a treatment failure and an ensuing relapse of secondary syphilis.  相似文献   
62.
Analyses of fetal heart rate (FHR) variability, visual evaluation of FHR decelerations, and respiratory gas analyses of the umbilical vein were performed in 27 labors, where one dose (50 or 75 mg) of intramuscular pethidine was used for pain relief, in 47 labors with one paracervical blockade (6 ml 0.5% marcaine) and in a control group of 135 labors without any pain relief. Umbilical vein pH, standard bicarbonate and base excess were lowest in the pethidine group and highest in the PCB group. The duration of labor was shortest in the control group, but there was no difference in the duration of labor of the two anesthesized groups. Intramuscular pethidine seems to associate with umbilical metabolic acidosis and PCB should be preferred to it, when an obstetrician is available.  相似文献   
63.
BACKGROUND: Erythropoietic protoporphyria (EPP) is an inherited disease caused by deficient activity of ferrochelatase in the heme biosynthetic pathway. Accumulation of protoporphyrins and light exposure results in acute phototoxic skin reactions. The histopathologic findings of the light-exposed skin are thickening of the superficial dermal vessel walls and amorphous deposits around the vessels, but the origin and detailed composition of the perivascular material have been unclear. OBJECTIVE: The vascular morphology and composition of the perivascular material were studied in the skin samples of patients with EPP. METHODS: Skin biopsy specimens of 8 patients with EPP representing 7 Finnish EPP families with different genotypes were studied by means of light and electron microscopy and immunohistochemical methods. RESULTS: The characteristic finding was thickened, periodic acid-Schiff-positive vessel walls caused by concentric reduplication of basal lamina and excess of fine granular material at the basal membrane zone in the superficial dermis. The perivascular deposits in the vicinity of vessel walls had a homogeneous or fine granular appearance without filaments. Direct immunofluorescence showed constant IgG deposits together with IgA, IgM, and C3 in the vessel walls. In immunohistochemistry, collagen IV and laminin could be demonstrated at the vascular basal membrane together with serum amyloid P protein, kappa and lambda light chains, and a 90-kd glycoprotein. CONCLUSION: The vascular involvement indicates that the blood vessel walls in the papillary dermis are the primary tissues affected during an acute photoreaction. The repeated acute damage and repair processes in the basement membrane zone result in thickening of the vessel walls. Perivascular deposits are a secondary and irreversible phenomenon resulting from the leakage and accumulation of different serum components. These changes were not found in the nonexposed skin, indicating that an increased level of erythrocyte protoporphyrin per se is not responsible for the cutaneous manifestations, but the interaction of solar radiation is mandatory. Amorphous deposits distinguish EPP from variegate porphyria and porphyria cutanea tarda; a histopathologic examination may be a helpful tool in differentiating porphyric and nonporphyric photosensitivity.  相似文献   
64.
Fetal magnetocardiography (FMCG) is a new complementary external method for accurate antepartal FHR recording. Because of the low magnetic noise level required it is not yet suitable for routine hospital use. Fifty-six simultaneous FMCG and external FECG measurements were made in order to compare these methods for instantaneous FHR recording. The error of the FHR value obtained with the instrumentation described is less than 1 per cent. Our results show that FMCG can be used for FHR processing from week 30 of gestation until term. Thirty-five of the measurements were done during this period. From these, a readable FHR curve was obtained in 21 cases with FMCG and in 12 cases with external FECG. The maternal complexes were always present in the FECG, but in only 15 of the recorded FMCG's.  相似文献   
65.
PURPOSE: To determine whether measuring signal intensity (SI) fluctuations in MRI time series data from acute stroke patients would identify ischemic tissue. MATERIALS AND METHODS: Prebolus perfusion-weighted MRI data from 32 acute ischemic stroke patients (N = 32) was analyzed as a time series. Ischemic and normal tissue regions were outlined and compared. RESULTS: The magnitude of the measured SI fluctuations was significantly lower in ischemic regions relative to normal tissue. Spatial differences in these fluctuations occurred in a manner that was different than other perfusion-based metrics. CONCLUSION: Prior studies have shown that SI fluctuations in MRI time series data correspond to the presence of physiological "noise," which includes vasomotion, an autoregulatory phenomenon that affects the tissue response to ischemia. In this study, SI fluctuations were found to decrease in ischemia, consistent with the notion that small vessels will remain open (fluctuations in vessel diameter will decrease) when there is a challenge to flow. Spatial variation in SI fluctuations appeared to be different from spatial variation seen on other perfusion-based metrics, suggesting that a separate contrast mechanism is responsible, one that might be of diagnostic and prognostic value in acute stroke in which the ability of tissue to withstand ischemia is currently not well visualized.  相似文献   
66.
Enamel matrix derivative Emdogain (EMD) is widely used in periodontal treatment to regenerate lost connective tissue and to improve the attachment of the teeth. Gelatinases (MMP-2 and -9) have an essential role in the promotion and progression of oral cancer growth and metastasis formation. We studied the effects of EMD on human tongue squamous cell carcinoma (HSC-3) cells in vitro and in vivo. In vitro, EMD (100 microg/ml and 200 microg/ml) remarkably induced the MMP-2 and -9 production from HSC-3 cells analysed by zymography and enzyme-linked immunosorbent assay. EMD also slightly induced the MMP-2 and -9 production from benign human mucosal keratinocytes (HMK). Furthermore, EMD clearly induced the transmigration of HSC-3 cells but had no effect on the HMK migration in transwell assays. The in vitro wound closure of HSC-3 cells was notably accelerated by EMD, whereas it had only minor effect on the wound closure of HMKs. The migration of both cell lines was inhibited by a selective cyclic anti-gelatinolytic peptide CTT-2. EMD had no effect on HSC-3 cell proliferation or apoptosis and only a limited effect on cell attachment to various extracellular matrix components. The in vivo mice experiment revealed that EMD substantially induced HSC-3 xenograft metastasis formation. Our results suggest that the use of EMD for patients with oral mucosal carcinomas or premalignant lesions should be carefully considered, possibly avoided.  相似文献   
67.
68.
Background and purpose The clinical findings of adverse reaction to metal debris (ARMD) following large-diameter-head metal-on-metal total hip arthroplasty (LDH MoM THA) may include periarticular fluid collections, soft tissue masses, and gluteal muscle necrosis. The ReCap-M2a-Magnum LDH MoM THA was the most commonly used hip device at our institution from 2005 to 2012. We assessed the prevalence of and risk factors for ARMD with this device.

Methods 74 patients (80 hips) had a ReCap-M2a-Magnum LDH MoM THA during the period August 2005 to December 2006. These patients were studied with hip MRI, serum chromium and cobalt ion measurements, the Oxford hip score questionnaire, and by clinical examination. The prevalence of ARMD was recorded and risk factors for ARMD were assessed using logistic regression models. The mean follow-up time was 6.0 (5.5–6.7) years.

Results A revision operation due to ARMD was needed by 3 of 74 patients (3 of 80 hips). 8 additional patients (8 hips) had definite ARMD, but revision was not performed. 29 patients (32 hips) were considered to have a probable or possible ARMD. Altogether, 43 of 80 hips had a definite, probable, or possible ARMD and 34 patients (37 hips) were considered not to have ARMD. In 46 of 78 hips, MRI revealed a soft tissue mass or a collection of fluid (of any size). The symptoms clicking in the hip, local hip swelling, and a feeling of subluxation were associated with ARMD.

Interpretation ARMD is common after ReCap-M2a-Magnum total hip arthroplasty, and we discourage the use of this device. Asymptomatic patients with a small fluid collection on MRI may not need instant revision surgery but must be followed up closely.  相似文献   
69.
70.
The posterior parietal cortex (PPC) has been associated with multiple stimulus‐driven (e.g., processing stimulus movements, providing visual signals for the motor system), goal‐directed (e.g., directing visual attention to a target, processing behavioral priority of intentions), and action‐related functions in previous studies with non‐naturalistic paradigms. Here, we examined how these functions reflect PPC activity during natural viewing. Fourteen healthy volunteers watched a re‐edited movie during functional magnetic resonance imaging (fMRI). Participants separately annotated behavioral priority (accounting for percepts, thoughts, and emotions) they had experienced during movie episodes. Movements in the movie were quantified with computer vision and eye movements were recorded from a separate group of subjects. Our results show that while overlapping dorsomedial PPC areas respond to episodes with multiple types of stimulus content, ventrolateral PPC areas exhibit enhanced activity when viewing goal‐directed human hand actions. Furthermore, PPC activity related to viewing goal‐directed human hand actions was more accurately explained by behavioral priority than by movements of the stimulus or eye movements. Taken together, our results suggest that PPC participates in perception of goal‐directed human hand actions, supporting the view that PPC has a special role in providing visual signals for the motor system (“how”), in addition to processing visual spatial movements (“where”). Hum Brain Mapp 35:4767–4776, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
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