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91.
The closure of ungrafted sacrococcygeal pilonidal sinus excisional wounds was studied in 15 patients. Wound punch biopsies were taken on a regular basis, and histologic sections were made. To document changes, computer-assisted morphometric image analysis was employed. Initial average wound depth was 37.8 +/- 4.6 mm, and complete closure (0 wound depth) was reached by 68 days. Wound contraction contributed 88 percent to wound closure, whereas the deposition of scar only contributed 12 percent. Maximum cells density within granulation tissue was reached by day 18. Myofibroblasts, identified by alpha-smooth muscle actin immunostaining, first appeared on day 11. Unlike those observed in laboratory animals, myofibroblasts were a minor cell population of granulation tissue, never exceeding 10 percent of the cells. The pattern of collagen fiber organization was documented by polarized light microscopy of Sirius red-stained sections. Early granulation tissue collagen fibers demonstrated a fine greenish birefringence, whereas more mature granulation tissue collagen fibers were thicker, displaying orange-yellowish birefringence. Myofibroblasts were associated exclusively with thicker collagen fibers, whereas fibroblasts were associated with both fine and thick collagen fibers. It is proposed that human wound contraction involves a volume change whereby normal dermal and adipose tissues are pulled into the defect by forces generated within fibroblasts.  相似文献   
92.
We studied the effect of percutaneous ethanol injection (PEI) in the treatment of cold, cytologically benign, large (>10 mL) thyroid nodules (CBNs) in 41 patients. The end-point of our study was to evaluate the efficacy of PEI on: 1) local symptomatology, assessed by an arbitrary symptom score; and 2) nodule volume and tracheal displacement (at ultrasonography). Follow-up ranged from 12-36 (21 +/- 9) months. Symptom score was significantly reduced (P < 0.01) after 6 months and at the end of the follow-up (2.1 +/- 0.3 vs. 0.2 +/- 0.5 and vs. 0.2 +/- 0.4). A significant (P < 0.01) nodule volume reduction was observed, without differences between solid or mixed CBNs; the reduction was 50% or more in 92.7% of patients. Neither clinical parameters nor pretreatment nodule ultrasonographic features were related to nodule reduction. Disappearance or significant reduction (>0.5 cm) of tracheal displacement was obtained in 61% and in 39% of patients, respectively. One patient experienced prethyroid region edema, pain, and mild fewer, which reversed within 1 week; and one patient had dysphonia, caused by vocal cord palsy, which reversed spontaneously within 1 month. At the end of the follow-up, nodules with just necrotic material at cytology showed a greater (P < 0.05) volume reduction than nodules with residual benign thyroid cells. Our data suggest that PEI is a safe and effective treatment of large CBNs, although sometimes serious side effects do occur.  相似文献   
93.
Our previous findings have shown that the developmental genes Pax7 and Pax3 are differentially methylated; the gene region that encodes the paired domain is hypomethylated, whereas the region that encodes the homeodomain is hypermethylated. For this reason, the known DNA sequence between the paired and homeoboxes was analysed for the presence of a conserved DNA motif to which a modifying protein could bind in order to direct the methylation or demethylation of surrounding gene sequences. The octapeptide-encoding region was found to contain several nucleotides that were highly conserved throughout the Pax gene family from phylogenetically distant species. The most conserved nucleotides are thought to comprise a motif TN8TCCT where N8=any combination of eight nucleotides. A conserved octapeptide-like-encoding sequence containing the TN8TCCT motif was also found in non-Pax genes of higher eukaryotes and in the non-coding strand of plants. Moreover, differential methylation seems to be associated with the presence of the TN8TCCT motif in p53 and the human oestrogen receptor genes. The presence of the TN8TCCT motif within an octapeptide-like-encoding sequence in human T-cell leukaemia virus type 1 might suggest that the putative recognition motif may have been introduced into various host genomes via some form of retroviral agent.  相似文献   
94.
A vertebrate host becomes infected with Leishmania major when the sand fly vector injects parasites into skin along with saliva. Previous studies showed that salivary gland lysate of the New World sand fly Lutzomyia longipalpis markedly enhanced L. major infection in CBA mice. However, L. major is an Old World parasite transmitted in nature by the Old World sand fly Phlebotomus papatasi. Here we examine the ability of P. papatasi salivary gland lysate to enhance infection (lesion size and parasite burden) by L. major. In addition, we examine the effects of salivary gland lysate on the immune response to L. major by monitoring the levels of cytokine mRNA from the lymph nodes draining cutaneous lesions. We found that P. papatasi salivary gland lysate dramatically exacerbated lesion development in disease-resistant CBA mice. This exacerbation of disease correlated with inhibition of the production of Thl cytokines and associated factors (IFN-gamma, IL-12, and inducible nitric oxide synthase), but with enhancement of the Th2 cytokine IL-4, whereas no changes in the levels of IL-10 and TGF-beta were noted. Importantly, salivary gland lysate directly up-regulated expression of IL-4 mRNA in mice in the absence of infection with L. major.  相似文献   
95.
The most common chromosomal aberrations in myelodysplastic syndromes (MDS) are complete or partial loss of chromosomes 5 and 7, and trisomy 8. To identify genes important in the pathogenesis of this disease that could be associated with these gross chromosomal defects, we have employed the differential display PCR (DDPCR) procedure developed by Liang and Pardee. This method allows simultaneous comparison of several cDNA sources for the presence of differentially expressed genes. Polymorphonuclear cells (PMNs) from two MDS patients, containing a 5q deletion or a trisomy 8, and three healthy controls were used. Initial screening resulted in the identification of five and three partial cDNA sequences, respectively that were either differentially expressed in both patient samples or in individual patients, as compared with the controls. The authenticity of aberrant expression was verified by reanalyzing the same primer combinations on newly prepared cDNA. Differential expression of the three remaining fragments was subsequently checked on a larger panel of MDS patients, using amplicon-specific primer sets. These were obtained by cloning and sequencing of the fragments. For one partial cDNA (DC3), the original expression pattern, i.e., decreased expression in individual MDS patients, was confirmed. These results demonstrate the utility of the DDPCR procedure to isolate differentially expressed sequences in primary patient samples where the availability of cells is a limiting factor.  相似文献   
96.
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT.  相似文献   
97.
Research in the 1980s uncovered ubiquitous neuropeptide-receptor distribution in brain structures associated with emotional processing, and throughout many organ systems. This finding supported neuropeptides as biochemical substrates of emotion, and the neuropeptide-receptor network as a parasynaptic system crossing traditional brain-body boundaries. The medical relevance of these findings was affirmed by psychoneuroimmunology research: neuropeptides help to regulate immunocyte trafficking, there is bidirectional communication between nervous and immune system components, immunocytes produce neuropeptides, and nerve cells produce immune-associated cytokines. In the past decade, the concept of a unified psychosomatic network has been strengthened by animal and human research demonstrating relationships between behavior and neuropeptide-mediated regulation of immune functions. Research on emotional expression or disclosure in healthy human subjects as well as in cancer and HIV-positive patients has shown significant positive correlations with clinically relevant immune functions and/or positive health outcomes. Psychosocial interventions emphasizing emotional expression or active coping have evidenced survival benefits in breast cancer and melanoma. These findings suggest that emotional expression generates balance in the neuropeptide-receptor network and a functional healing system. Emotional expression is also a marker for psychospiritual vitalization, and further research should evaluate links between energy-based models of health and neuropeptide-receptor-based models under the rubric of an informational paradigm.  相似文献   
98.
Experiments on a torsional oscillator containing a slab of liquid3He of thickness 105 µm and diameter 8.38 mm are described. Normal phase experiments confirm the theory of the oscillator dynamics but an apparent descrase in the measured value of T 2 at lowT casts doubt on the existing slip theory. Measurements for the uniform texture for the A phase give values of s and 44. The s measurements suggest that the A-phase energy gap is enhanced by a factor 1.24 over the BCS value. Distortion of the uniform texture by a magnetic field perpendicular to the slab occurs at a threshold field slightly smaller than predicted. Measurements for fields at different angles to the slab enable accurate values to be deduced for the superfluid density anisotropy and two other viscosity coefficients. The remaining two viscosity coefficients are only poorly determined. Flow alignment of the orbital texture was achieved by increasing the oscillator amplitude. A different texture obtained on some occasions after warming from the B phase was investigated but is not understood.  相似文献   
99.
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