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71.
Optimal sentinel node identification requires using the combination technique with blue dye and radiocolloid. Allergic reactions to the common blue dyes in use are well recognised. In this report, we present a patient with breast carcinoma who developed a type I hypersensitivity reaction to intradermal injection of technetium-99m labelled nanocolloidal albumin. While reactions to colloids are rare, and in this case minor, operators using this radiopharmaceutical should be prepared for a potential severe anaphylactic reaction.  相似文献   
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Background. Vitiligo is an acquired idiopathic and polygenic disorder with progressive depigmentation of circumscribed patches. Its exact pathogenesis is unknown. The CD4 gene plays an important role in the cell‐mediated immune response and its association with type 1 diabetes mellitus, which is an autoimmune disease, has been previously reported. Methods. Based on the assumption that autoimmunity is also involved in vitiligo, the CD4 gene was selected for study using a candidate gene approach. The pyrimidine‐rich pentanucleotide repeat length polymorphism located in the promoter of the gene was studied. We screened 144 unrelated Iranian patients with vitiligo and 144 healthy matched controls by PCR. Results. The CD4*A4 allele has a susceptibility association with the development of vitiligo in the Iranian population (OR = 1.68, 95% CI 1.18–2.42; P < 0.01, Pc = 0.02). When we compared CD4*A4‐containing genotypes in the case and control groups, even more significant positive association was identified (OR = 2.02, 95% CI 1.26–3.22; P < 0.01 and Pc < 0.01). The CD4 gene polymorphism has a modest association with the development of vitiligo in Iranian patients.  相似文献   
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Theta burst stimulation (TBS) and primed bursts (PBs) stimulation are among the effective tetanic stimulations for induction of long-term potentiation (LTP) in the hippocampus. Recent studies have indicated that TBS is effective in LTP induction of layer III synapses of neocortex, only if applied to layer IV. However, the possibility of neocortical LTP induction using PBs has not been investigated yet. Sensory deprivation greatly influences the development of neocortex. According to the effect of sensory deprivation on synaptic plasticity of developing neocortex, we studied the induction of LTP by PBs in visual cortical slices of control and dark-reared rats. The results showed that application of PBs to layer IV could effectively induce LTP of layer II/III field potentials. These potentials are consisted of two components: pEPSP1, (population excitatory postsynaptic potential 1) and pEPSP2. In control slices PBs led to selective potentiation of pEPSP2. Visual deprivation increased the incidence of LTP of pEPSP1 and decreased the amount of LTP of pEPSP2. These findings showed that PBs could be used as an effective tetanic stimulation to study the synaptic plasticity in neocortex. The effects of visual deprivation on PBs-induced LTP are consistent with its role in the development of excitatory system in neocortex.  相似文献   
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Oxygen transport, the major function of hemoglobin, is dependent upon reduced heme iron. In the red cell, the heme iron is maintained in the reduced form by the methemoglobin reduction system. When the balance between oxidation and reduction of heme iron is perturbed due to the presence of excessive oxidants, decreased reducing capacity or the presence of abnormal hemoglobin, methemoglobinemia ensues. In most cases methemoglobinemia is transitory and of no major clinical consequence. Occasionally, however, it can be life threatening and must be rapidly diagnosed and treated. When methemoglobinemia is of hereditary nature, either due to deficiency of red cell NADH-methemoglobin reductase or due to the presence of M hemoglobin, it is a lifelong problem. Since most of these patients do not have major disabling symptoms, the treatment is aimed at correction of cyanosis.  相似文献   
79.

Background

Although infections associated with penile implants are relatively infrequent, they result in serious medical consequences. Because treatment of these infections usually requires removal of the infected penile implant, prevention of infection is crucial. Since bacterial colonization of the implant is a prelude to clinical infection, antimicrobial modification of the devices may inhibit device colonization and subsequent infection.

Objective

We compared the spectrum and durability, both in vitro and in vivo, of two antibiotic-treated penile prostheses: InhibiZone implants pre-impregnated with minocycline and rifampin (M/R) and Titan implants dipped in vancomycin.

Design, setting, and participants

1 × 1-cm cylinder segments of (1) control untreated, (2) M/R-impregnated, and (3) vancomycin-dipped implants were studied. Baseline zones of inhibition (ZI) were determined against clinical isolates, including methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant S. epidermidis (MRSE), vancomycin-resistant Enterococcus (VRE), and Escherichia coli. In addition, ZI against methicillin-susceptible S. aureus were compared both in vitro after being washed in a flow chamber and after subcutaneous implantation in rabbits for 1, 2, 7, and 14 d.

Measurements

ZI were measured as the diameter of the clear zone around each test device minus the external diameter of the device.

Results and limitations

Implants pre-impregnated with M/R displayed a broader spectrum of antimicrobial activity than vancomycin-dipped implants against both gram-positive and -negative bacteria. The M/R-impregnated devices also yielded significantly larger zones of inhibition against S. aureus than vancomycin-dipped implants, both in vitro (p < 0.003) and in vivo throughout the 14-d period of device implantation in rabbits (p ≤ 0.03).

Conclusions

Penile prostheses impregnated with M/R have a broader spectrum in vitro and a more durable antimicrobial activity in vitro and in an animal model than implants dipped in vancomycin. Therefore, along with being a more practical model for incorporating antimicrobials onto the device, the use of implants pre-impregnated with M/R may help reduce the incidence of penile implant infection.  相似文献   
80.
Chronic granulomatous disease (CGD) is an inherited disorder of pathogen killing by phagocytic leukocytes caused by mutations in NADPH oxidase subunits. Patients with CGD have life-threatening bacterial and fungal infections. Children’s Medical Center at Tehran University is the referral center for immunodeficiency in Iran. During 2 years of study, 11 non-consanguineous families with clinically diagnosed CGD were referred to this center. In functional assays performed on neutrophils from affected children and their mothers; no activity or strongly decreased oxidase activity was detected in the patients’ cells. In oxidase tests that scored this activity on a per-cell basis, a mosaic pattern was detected in the neutrophils from all 11 mothers. Western blot analysis revealed an X91° phenotype in all patients. Mutation screening in the CYBB gene encoding gp91phox by SSCP analysis followed by sequencing showed nine different mutations, including two novel mutations. The present survey is the first study aimed to analyze the clinical features and the molecular diagnosis of X-CGD in Iranian patients.  相似文献   
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