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61.
Abstract: Unusually prolonged pressure on the scalp by the cervical os during or before the delivery may result in a distinctive pattern of annular alopecia that has been referred to as halo scalp ring. This rare form of hair loss is most commonly a temporary, non‐scarring process that is attributed to caput succedaneum. We report a new case of halo scalp ring in a premature newborn. Review of previously reported cases suggests that prematurity is an important, previously unrecognized, risk factor for developing a halo scalp ring.  相似文献   
62.
Calafianin (1) and two known compounds, aerothionin and (3, 5-dibromo-2-hydroxy-4-methoxyphenyl)acetic acid, were isolated from the marine sponge Aplysina gerardogreeni. The structure of 1 was determined by NMR analysis and mass spectrometry.  相似文献   
63.
Bell's palsy has no specific treatment because its cause is still debated. The most widely accepted theory postulates an immunovirological origin consisting of the reactivation of a silent herpesvirus on the geniculate ganglion. We studied three groups of patients with Bell's palsy who received different treatments in an attempt to discern differences in evolution between treatment groups.  相似文献   
64.
From the root of Calliandra californica two new cassane-type diterpenes were isolated and characterized, escobarine A (1) and B (2), which showed promising activities against two Mycobacterium tuberculosis strains. The microplate alamar blue assay was used to determine the minimum inhibitory concentrations (MIC) of 1 and 2 against M. tuberculosis H37Rv and the resistant CIBIN/UMF15 : 099 strains. The MIC of 1 against the resistant M. tuberculosis strain showed a value 8 times lower than that of rifampin. The structures of the bioactive constituents were established by extensive NMR data analyses (including 1D and 2D NMR). The relative configuration of 2 was confirmed by X-ray analysis and the absolute configurations of 1 and 2 were determined by the circular dichroism method. Additionally, 1 and 2 displayed remarkable cytotoxic activity when evaluated against five human tumor cell lines.  相似文献   
65.
OBJECTIVES: To validate the ability of a hospital administration data set (minimum data set [MDS]) to detect incident cases of colorectal cancer using the Murcia Cancer Registry (MCR) as the gold standard and to measure agreement between the MDS and registration of colorectal cancer. MATERIAL AND METHOD: A cross sectional validation study of the MDS of the main hospital in the region of Murcia (Spain) was conducted. The study population consisted of incident cases of colorectal cancer in 2000 obtained from the MCR and cases in the MDS of the above-mentioned hospital for the same year with an ICD-9 diagnostic code between 153.0 and 154.1, eliminating readmissions. During the process, two analyses were performed: one analysis with the principal diagnosis only and another with all the diagnostic codes. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and agreement was calculated with their 95% confidence intervals (CI). RESULTS: With the first diagnosis only, the MDS detected 80% of the incident cases of colorectal cancer with a PPV of 75%. With all the diagnoses, the MDS detected 85% of the cases with a PPV of 64%. The agreement in codification was high at three digits (kappa 88% [95% CI, 0.79-0.97] first diagnosis, 89% [95% CI, 0.80-0.97] all diagnoses) as well as at four digits (kappa 77% [IC, 0.68-0.85] first diagnosis, 78% [95% CI, 0.70-0.86] all diagnoses) in both analyses. CONCLUSIONS: Because of its high sensitivity, the MDS is a good source for detecting incident cases of cancer. The high agreement found in the site of colorectal cancer helps to consolidate the MDS as a data source for cancer registration.  相似文献   
66.
In an attempt to find new compounds with neuroprotective activity, we have designed, synthesized and characterized 19 new nNOS inhibitors with a 4,5-dihydro-1H-pyrazole structure. Compounds 11r [1-cyclopropanecarbonyl-3-(2-amino-5-chlorophenyl)-4,5-dihydro-1H-pyrazole] and 11e [1-cyclopropanecarbonyl-3-(2-amino-5-methoxyphenyl)- 4,5-dihydro-1H-pyrazole] show the highest activities with inhibition percentages of 70% and 62%, respectively. A structure-activity relationship for the nNOS inhibition can be established from the structural comparison of these new pyrazole derivatives and the described synthetic kynurenines 10.  相似文献   
67.
Because of the probable involvement of cholinesterases (ChEs) in tumorigenesis, this research was addressed to ascertaining whether breast cancer metastasis alters the content of acetylcholinesterase (AChE) and/or butyrylcholinesterase (BuChE) in axillary lymph nodes (LN). ChE activity was assayed in nine normal (NLN) and seven metastasis-bearing nodes (MLN) from women. AChE and BuChE forms were characterised by sedimentation analyses, hydrophobic chromatography and western blotting. The origin of ChEs in LN was studied by lectin interaction. AChE activity dropped from 21.6 mU/mg (nmol of the substrate hydrolysed per minute and per milligram protein) in NLN to 3.8 mU/mg in MLN (p < 0.001), while BuChE activity (3.6 mU/mg) was little affected. NLN contained globular amphiphilic AChE dimers (G2 A, 35%), monomers (G2 A, 30%), hydrophilic tetramers (G4 H, 8%), and asymmetric species (A4, 23%, and A8, 4%); MLN displayed only G2 A (65%) and G2 A (35%) AChE forms. NLN and MLN contained G4 H (79%), G4 A (7%), and G1 H (14%) BuChE components. Neither the binding of ChE forms with lectins and antibodies nor the subunit size were altered by metastasis. The higher level of AChE in NLN than in brain and the specific pattern of AChE forms in NLN support its role in immunity. The different profile of AChE forms in NLN and MLN may be useful for diagnosis.  相似文献   
68.
Patients undergoing autologous peripheral blood stem cell transplantation (PBSC) frequently require the sequential insertion of two central venous catheters, one for leukapheresis and one for transplant support. Hybrid catheters suitable for leukapheresis and long-term use have been increasingly used, but there is limited information regarding their performance and complication rate. The purpose of this study was to determine the performance of the Pheres-Flow hybrid catheter when utilized for both leukapheresis and transplant support, with particular emphasis on the incidence of infectious and occlusive complications. We prospectively analyzed the performance of 92 catheters in 82 consecutive patients who underwent autologous peripheral blood stem cell (PBSC) transplantation. Occlusion was the most frequent complication of this catheter with 29% of the patients experiencing difficulty drawing blood or infusing fluids. Infection was another frequent complication. Twenty-two percent of patients developed catheter-related bloodstream infections and 15 catheters had to be removed because of proven or suspected infection that did not respond to antibiotic therapy. Nevertheless, 77% of patients were able to complete leukapheresis and transplant support with only one catheter. We conclude that the utilization of the Pheres-Flow catheter for both leukapheresis and transplant support is feasible, but that new strategies need to be developed to decrease the incidence of occlusive and infectious complications of hybrid catheters.  相似文献   
69.
70.
Severe pulmonary hypertension (PH) mimicking idiopathic PH is an increasingly recognized complication of human immunodeficiency virus (HIV) infection. PH shares several histopathologic features with Kaposi's sarcoma (KS), the most common malignancy in AIDS patients, and molecular evidence of the vasculotropic Kaposi's sarcoma-associated herpesvirus or human herpesvirus 8 (HHV-8) has been found in the lung tissue of patients with the disease. Although the prevalence of HHV-8 infection is increased among HIV-infected patients, no clinical association between KS and PH has ever been reported. Herein, we described a 30-year-old HIV-infected female co-infected with HHV-8 who developed severe PH coincident with occult KS. The clinical presentation of KS was unusual and remained masqueraded for years as an indolent cervical lymphadenopathy, without the typical cutaneous lesions. This is the first ever-reported case of PH associated with KS. Although the co-occurrence of both diseases in this patient could have been just a coincidence, the observation may also indicate that a relationship between HHV-8 infection and HIV-associated PH exists. Coinfection with HHV-8 and occult lymphadenopatic KS should be considered in HIV-infected patients developing PH.  相似文献   
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