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81.
The changes in viral load and CD4(+) count at 3 and 6 months in a group of 166 HIV-infected patients was evaluated. The new therapy was chosen based on the medical history procedures for 70 patients, and in 96 patients it was guided by the partial or complete result of the line probe assay (LiPA) HIV RT and Protease resistance tests. The absolute difference from the baseline of the log viral load at 3 and 6 months was significantly different between the two groups when adjusted for baseline viral load (P < 0.0001) and stayed significant when intention-to-treat analysis was carried out (P < 0.001). The absolute difference of the CD4(+) count was not significantly different when adjusted for baseline CD4(+) (P = 0.854, 3 months; P = 0.06, 6 months). The proportion of patients with a viral load 相似文献   
82.
83.
Tuberculosis is a public health problem. If the current trends continue, is expected to arrive to 10.2 million of new cases in 2005. There are three studies accomplished in 1995 in Mexican patients. The results show important difficulty in the application and the follow-up of the program of control of the tuberculosis, what has caused accumulation of chronic cases, moderate rate of primary resistance and alarming levels of primary and secondary multiresistance (23%). Mechanism of protective immunity against mycobacterium tuberculosis (MTB) in humans have not been clarified. Different subpopulations of lymphocytes CD4, CD8 and other populations as well as macrophages, and monocytes, have an important role. In industrialized countries, the managing of the MDRTB is based on the use of individualized treatments with second line drugs according to susceptibility test, however the foregoing has not been possible to apply it middle or low income countries. WHO has launches the initiative "DOTS plus" that consist in the administration of a standarized regimen on the basis of epidemiology of resistance in the country or region.  相似文献   
84.
Patients with hepatitis C virus (HCV) chronic infection present some extrahepatic manifestations that may mimic the clinical, immunologic and histological manifestations of primary Sj?gren's syndrome (SS). Thus, HCV patients with sicca symptomatology and positive autoantibodies could be misdiagnosed as a 'primary' SS. Nevertheless, there are several clinical and immunologic features that could help us differentiate both processes.  相似文献   
85.
86.
Four new HLA classical class I alleles in the three loci are described in Caucasian individuals. A*3012 was first suspected by an abnormal serologic pattern that would be explained by the single amino acid substitution at the A30-specific Ser17. B*270505 differs from B*270502 in a silent substitution at an up to now constant position in the B locus. B*3541 encodes for a new Cys at position 118 that has not been encountered in neither human nor primate alleles. Cw*0716 seems to be originated by a large-scale interallelic recombination event between Cw*0701/*0706/*0718 and Cw*020202, giving rise to a new antigen-binding cleft conformation.  相似文献   
87.
Papillon-Lefèvre syndrome (PLS) has recently been shown to be caused by mutations in the cathepsin C gene resulting in periodontal disease and palmoplantar keratosis. Thirteen different homozygous mutations have been characterised in PLS patients of different ethnic origin. In the present paper, a PLS patient is described who carries two novel mutations (706G>T and 872G>A) in the paternal and maternal chromosomes, respectively. This is the first compound patient described so far. In addition, a novel symptomless mutation (458C>T) in the cathepsin C gene is described in three homozygous individuals. Thus, not all mutations should be considered as a cause of disease, whether case studies or general population screening is performed. Another already described mutation that provoked the Haim-Munk syndrome (HMS) in Indian Jews has also been found to give rise to PLS in a Spanish family from Madrid. On the other hand, PLS patients are ameliorated by retinoids, which indicates that retinoids may be used as therapeutic agents in this immune system deficiency.  相似文献   
88.
Fluorescence in situ hybridization (FISH) is a useful cytogenetic technique for the detection of chromosome aberrations. However, applying this technique routinely on paraffin-embedded tissue is hampered by technical problems. The efficiency of hybridization is influenced by formalin fixation time, and this may vary considerably between specimens. We present a simple method for improving hybridization by microscopically monitoring the time of enzymatic digestion. To establish optimal digestion time, enzymatic digestion was stopped at 3-minute intervals for biopsies and 10-minute intervals for autopsies in 24 paraffin-embedded samples. At every stop, tissue morphology was examined under light microscopy to determine if observed changes could be correlated with subsequent FISH results. The appearance of fernlike formations was found to mark the optimal digestion time that produced the strongest hybridization signals. Using this method of digestion time control, an additional 41 cases were evaluated for FISH with various types of probe. Monitoring under the microscope could be more spaced if the morphology did not change after the first visual control and could be adapted to the type of sample (in general, endoscopic samples, total digestion time of about 10 min; routine biopsies, 15 to 30 min; autopsy samples, 20 to 40 min). In every case, the appearance of the fernlike pattern correlated with proper hybridization signal. Monitoring digestion time for the appearance of fernlike structures is a useful method for improving reproducibility of FISH technique on paraffin-embedded samples. It is particularly useful when dealing with samples under heterogeneous fixation conditions (consultations, autopsies, etc.), because it eliminates the need for repetition.  相似文献   
89.
MHC-G is a class Ib (non-classical) major histocompatibility complex (MHC) whose functional and evolutionary characteristics are still under scrutiny. The study of noncoding sequences in the MHC genes may provide important phylogenetic information. In this work we have sequenced the MHC-G exon 8, which encodes for the 3'UT region, in different species of primates. It has been shown that: (1) a previously described 14 base pair (bp) deletion polymorphism is human-specific and the HLA-G alleles may be classified according to its absence or presence; (2) another newly described 3 bp deletion/insertion polymorphism is also human-specific; and (3) another newly described 51 bp deletion polymorphism is common to Pongidae and humans, but is not found in other primates belonging to the Cercopithecinae family. A hypothesis on the evolutionary pathway of this gene is put forward in the light of these findings.  相似文献   
90.
The current study analyzes the rearrangement pattern of immunoglobulin H (IgH), T-cell receptor (TCR)-gamma, and TCR-beta genes in a group of 80 non-Hodgkin's lymphomas (NHL) of different histologic subtypes (43 B-cell and 37 T-cell types). The sensitivity and specificity provided by polymerase chain reaction amplification of these loci are evaluated. The association between the proliferation index and the presence of the so-called "aberrant" or "dual" rearrangements is also considered. Ninety-one percent of B-cell NHL showed IgH gene monoclonality, and 21% also exhibited a monoclonal pattern in one of the TCR genes. Among T-cell NHL, the sensitivity of the study was 65% for the TCR-gamma gene and 46% for the TCR-beta gene. The total sensitivity was 76%, amplifying both loci. IgH gene aberrant rearrangements were observed in 16% of T-cell neoplasms. A substantial percentage of dual rearrangements were detected in precursor and mature B- and T-cell NHL. B-cell NHL showed a tendency toward higher values of proliferation when aberrant rearrangements were present; however, this trend was not significant. Furthermore, in the case of T-cell NHL there was a significant negative association between these two variables.  相似文献   
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