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161.
Several quantitiative methods of urine microscopic examination for bacteriuria and pyuria on a blood cell counting-chamber have been found reliable for the diagnosis of urinary tract infection (UTI). However, no one technique has become popular or widely used because of laborious procedures associated with the method. We investigated the usefulness of microscopic examination of uncentrifuged urine on disposable counting-chambers. A total of 89 urine samples were obtained from 53 children (24 male and 29 female). Urine samples were examined for bacteriuria and pyuria using a disposable counting chamber and its reliability was analyzed in predicting significant bacteriuria defined by routine urine culture. Significant bacteriuria was diagnosed in 23 of 89 urine samples by urine culture. Microscopic urine examination on disposable counting-chambers was very easy without the need to set up or wash chambers and provided immediate information. Urine bacterial concentration determined by the counting-chamber method was closely correlated to that determined by bacterial culture. The counting-chamber method identified bacteriuria correctly in 21 of 23 urine samples diagnosed as significant bacteriuria (sensitivity = 91%) and also gave a correct diagnosis of 64 of 66 urine samples with non-significant bacteriuria (specificity = 98%). Nineteen of the 23 urine samples with significant bacteriuria also had pyuria. The positive predictive value of concomitant bacteriuria and pyuria was 100%. When neither bacteriuria nor pyuria was found, the negative predictive value was 100%. It was concluded that urine microscopy using disposable counting chambers was very easy, inexpensive, quick and reliable and thus an extremely useful method for diagnosing UTI.  相似文献   
162.
An infant with cytomegalovirus infection (CMV) developed idiopathic thrombocytopenic purpura (ITP) at 4 months of age. A bone marrow (BM) aspiration showed a remarkable increase of immature megakaryocytes and prominent proliferation of lymphoblasts. Flow cytometric analysis of the bone marrow cells showed that the predominant cells in the lymphocyte cluster were of B-lineage (CD19) with CD10 (common acute lymphoblastic leukemia antigen) positive. Virus study showed a high titer of CMV antibody. Cytomegalovirus DNA was detected by the polymerase chain reaction (PCR) method in urine, peripheral cells and marrow cells. Low-grade fever, diarrhea and petechiae were accompanied by mild liver dysfunction. Complete remission was made with intravenous high-dose immunoglobulin (IVIg) without progression to overt acute leukemia. The percentage of CD10+/CD19+ lymphocytes in bone marrow also diminished. We postulated that the proliferation of immature lymphocytes and megakaryocytes in bone marrow was caused by maturation arrest that might result from CMV infection.  相似文献   
163.
A report is presented of a male infant with prune belly syndrome (PBS) in whom bladder enlargement was detected by ultrasound (US) as early as 13 weeks of gestation. Subsequent fetal US identified progressive urinary tract dilatation, ascites and oligohydramnios. At 22 weeks, the fetal bladder was drained under US guidance. A gradual resolution of oligohydramnios was detected on US performed after 26 weeks of gestation. Delivery by cesarean section was performed at 34 weeks of gestation. The newborn had typical features of PBS with a vesico-cutaneous fistula but did not show respiratory distress. Imaging studies showed hypoplastic left kidney, slightly dysplastic but functioning right kidney, megaureter, megacystis, vesicoureteral reflux and dilated prostatic urethra. The early detection of genitourinary system abnormalities and serial US suggest that a distal urethral obstruction may be the underlying mechanism of PBS. Spontaneous (or therapeutic) intra-uterine decompression of the bladder might ameliorate obstructive nephropathy and oligohydramnios, allowing adequate lung development.  相似文献   
164.
Measles is often fatal for immunocompromised hosts. Protective immunity against measles has been studied but is still not completely understood. Recently, five cases of measles were encountered in immunocompromised children. Two of these were allogeneic bone marrow transplanted cases (one common variable immunodeficiency and one severe aplastic anemia) in remission, one Wilms' tumor case in remission, one hepatoblastoma case after cytotoxic therapy at disease onset and one exaggerating hemophagocytic syndrome case with suppressed natural killer cell activity. Clinical symptoms, laboratory findings and the immunologic backgrounds of these five patients were investigated. One of the patients, an 8 year old boy with hemophagocytic syndrome, died of giant cell pneumonia which was confirmed in the section of necropsy lung specimen. Two other patients who received allogeneic bone marrow transplants were not immune to measles, despite their own and their donors' immunizations. Their clinical symptoms were rather severe but both patients recovered and have remained seropositive for as long as 13 months. This fatality from measles is the first reported in a patient with hemophagocytic syndrome. Suppressed natural killer cell activity may be a poor prognostic factor. Also, secondary immunization failure for measles can occur in bone marrow transplanted patients with rather severe clinical symptoms.  相似文献   
165.
Several less harmful methods than voiding cysto-urethrography for detecting significant ureteric reflux have been proposed. The present prospective study investigated whether ultrasonography was effective in identifying ureteric reflux in infants with their first febrile urinary infection. The subjects were 27 infants (24 boys and 3 girls) aged from 0 to 8 months. The urinary tract was scanned when the bladder was full, and before and during induced voiding. Infants with abnormal ultrasound findings underwent voiding cysto-urethrography. The other infants were followed and those who had a recurrence of urinary infection underwent voiding cystography. Ten children underwent cysto-urethrography, with eight refluxing ureters identified in six boys. Ultrasound revealed transient dilatation of the renal pelvis on voiding in five kidneys, transient dilatation of distal ureters in 12 and hydro-ureteronephrosis in two. Each of the five kidneys with pelvic dilatation on voiding was associated with ureteric reflux grades III or IV. Of the 17 children who did not undergo cysto-urethrography, only one had recurrence of urinary infection and was diagnosed with ureteric reflux. This girl was one of the three babies who were not scanned during voiding. More than half of the infants with febrile urinary infection were excluded from invasive examination without having recurrence of urinary infection. Thus, ultrasound scanning during voiding was effective for screening infants with their first urinary infection to detect significant ureteric reflux.  相似文献   
166.

Purpose

Inhibitory effects of TNP-470, a synthetic analogue of the antibiotic fumagillin secreted by Aspergillus fumigatus, were studied with respect to growth and lung metastasis of the hormone-independent rat prostatic carcinoma cell line AT6.3.

Materials and Methods

Rat prostatic carcinoma AT6.3 cells were implanted in nude mice subcutaneously. Antimetastatic and growth-inhibitory effects of TNF-470 in vivo were examined 3 weeks after inoculation of AT6.3 cells. Direct growth-inhibitory effect was examined by MTT assay in vitro.

Results

TNP-470 inhibited the growth of AT6.3 cells in vitro. Subcutaneously injected TNP-470 markedly reduced numbers and individual size of lung metastases from AT6.3 cells inoculated percutaneously or intravenously into male BALB/c-nu/nu mice.

Conclusion

This agent, which acts as an angiogenesis inhibitor, may prove to be clinically useful in preventing metastasis of hormone-independent prostatic cancer.  相似文献   
167.
168.
BACKGROUND: As a first step to formulate a new treatment strategy for refractory acute lymphoblastic leukemia (ALL) in infants, clinical results and immunophenotypic and cytogenetic data were analyzed and compared with those from overseas. METHODS: There were 62 infants with ALL who were treated between 1977 and 1995 at 30 institutions affiliated with the Tokyo Children's Cancer Study Group. Clinical and laboratory data obtained from these infants (all under 1 year of age) were retrospectively studied. RESULTS: The morphological diagnoses were FAB-L1 for 51 patients (82.2%) and FAB-L2 for 11 patients (17.8%). Hepatomegaly and splenomegaly were found in 40 (70.0%) and 40 patients (68.3%), respectively. The mean (+/- SEM) leukocyte count at diagnosis was 205,900 +/- 35,700/microL. The involvement of the central nervous system was evident in nine of 36 patients who were subjected to lumbar puncture, while three of these nine patients were free of neurological symptoms at diagnosis. Thirty-one patients (55.4%) were CD10 negative and 14 (25.0%) were CD10 positive. Thirty-one of 47 patients (65.9%) exhibited chromosomal abnormalities, including 28 patients (59.6%) with 11q23 abnormalities. Rearrangements in the MLL gene were found in nine of 13 infants (69.2%) examined. Translocation of 11q23 and/or MLL gene rearrangement (11q23/MLL) was significantly associated with the absence of the CD10 antigen. Hyperleukocytosis of more than 50,000/microL and 11q23/MLL gene rearrangements were related to a poor prognosis. The probability of an event-free survival in 62 infants was 13.1 +/- 4.8% at 48 months. CONCLUSIONS: New therapeutic strategies and large-scale cooperative prospective trials are needed to improve the prognosis of ALL in infants.  相似文献   
169.
PURPOSE: To evaluate the practical value of initial C-reactive protein (CRP) in the diagnosis of bacterial infection in children. METHODS: The subjects comprised 11 children, six boys and five girls, aged 3 months through to 3 years (median age 16 months), whose initial CRP levels were < 1.0 mg/dL despite bacterial infection. C-reactive protein was quantitated at the first medical examination by nephelometry. RESULTS: The diagnosis was urinary tract infection (n = 4), bacterial meningitis (n = 2), sepsis (n = 2), pneumonia (n = 2) and arthritis of the hip joint (n = 1). The CRP levels were significantly elevated during the course of infection, ranging from 7.6 to 28.5 mg/dL. The bacterial etiology was non-specific. Eight patients were examined within 12 h of onset, three exhibited negative CRP values despite the duration of the insult over 12 h. Six patients were tentatively diagnosed as having a bacterial infection, but the other five were not. Each patient was treated, leading to a favorable outcome without any serious complications. CONCLUSIONS: Low levels of CRP do not rule out the possibility of bacterial infection in children. The initial value of CRP may be negative, even in patients with severe bacterial infection or even after 12 h from onset. The data suggest that pediatricians should consistently be aware of the possibility of bacterial infection even if the initial CRP test result is negative and that serial CRP measurements appear to be practical.  相似文献   
170.
The giant cell tumour of tendon sheath (GCTTS) is mainly composed of mononucleated stromal cells (SC) and multinucleated giant cells (GC), so-called osteoclast-like GC. It is thought that GC are derived from SC, but their precise relationship is not fully understood. Parathyroid hormone (PTH)-related peptide (PTHrP) is now considered to be a cytokine for cell differentiation, which may stimulate osteoclast-like cell formation in haematopoietic cells. Five cases of GCTTS were evaluated immunohistochemically, using a variety of antibodies against PTHrP, PTH/PTHrP receptor, KP-1 as a histiocytic phenotypic antigen, fibronectin as a fibroblastic phenotypic antigen, and proliferating cell nuclear antigen (PCNA). In situ hybridization and immunohistochemistry revealed that in all cases both SC and GC expressed PTHrP. PTH/PTHrP receptor was observed only in histiocytic SC and GC, but not in fibroblastic SC. Almost all GC showed histiocytic features. PCNA immunoreactivity was detected only in the nuclei of SC, and not in GC. Moreover, SC with PTH/PTHrP receptor immunoreactivity were negative for PCNA. These results suggest that GC are derived from histiocytic SC expressing PTH/PTHrP receptor and losing proliferative activity in the process of transition from mononuclear to multinucleated. PTHrP produced by SC and GC may be involved in the formation of osteoclast-like cells in GCTTS by acting in an autocrine/paracrine fashion.  相似文献   
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