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41.
本研究的目的是提高用过氧化物酶试验检测精液中的白细胞时所得的圆形细胞数量的精确度。精液样本的圆形细胞浓度在(0.6~6)×10^6/mL之间,降低精液的稀释度,增加被测悬浮液的体积。1+5(1:6)的稀释度适合于测量过氧化物酶活性,并能为细胞检测提供足够清晰的背景。在该稀释度下,测定Neubauer-改良精子计数板两边所有18个网格中的细胞数量,额定细胞浓度为(1.9~3.3)×10^6/mL的10个样本中只有3个样本的圆形细胞数/〉400个。由于更低浓度的精子稀释液不适合测定圆形细胞或其过氧化物酶反应产物,所以无法精确测量(抽样误差5%)参考下限值(1×10^6/mL)。结果表明,正是由于测定精液中的10个样本中圆形细胞很难精确到1×10^6/mL,所以白细胞精液症临界值的确定一直存在诸多分歧。因此需要建立一些统计学上合理的参考限。  相似文献   
42.
Journal of Neurology - Parkinson’s disease (PD) is an ageing disorder with deterioration of dopamine neurons which leads to motor complications like tremor, stiffness, slow movement and...  相似文献   
43.
BACKGROUND: Preoperative autologous blood donation is accepted as a standard of care for radical prostatectomy. Acute normovolemic hemodilution (ANH) is an alternative method for obtaining autologous blood. The cost and benefits of these two autologous blood-collection techniques are compared. STUDY DESIGN AND METHODS: Thirty consecutive patients scheduled for radical prostatectomy underwent ANH to a target hematocrit level of 28 percent. Blood was transfused in the perioperative period to maintain the hematocrit level > 25 percent. Hematocrit levels, transfusion outcomes and costs, and postoperative outcomes for these patients (hemodilution group) were compared with a matched patient cohort who preoperatively donated 3 units of blood for autologous use in prostatectomy surgery (nonhemodilution group, n = 30). RESULTS: Thirty patients underwent ANH to a hematocrit level of 28.7 +/− 1.7 percent, and 1740 +/− 346 mL (3.5 +/− 0.7 units) of blood were collected. Three (10%) of the patients in each cohort had allogeneic blood exposure. Transfusion costs were 73 percent higher for the nonhemodilution group patients than for the hemodilution group patients ($330 +/− $100 vs. $191 +/− $55, p < 0.001). No differences were found in postoperative outcomes. CONCLUSION: An integrated blood conservation program utilizing hemodilution and a defined transfusion trigger can decrease the requirement for preoperative donation of blood for autologous use in radical prostatectomy. Point-of-care autologous blood procurement is more cost-effective than preadmission donation of autologous blood units.  相似文献   
44.
Inhorn  L; Fleming  JW; Klingberg  D; Gabig  TG; Boswell  HS 《Blood》1988,71(4):1003-1011
Mechanisms of leukemic cell clonal dominance may include aberrations of transmembrane signaling. In particular, neoplastic transformation has been associated with reduced capacity for hormone-stimulated adenylate cyclase activity. In the present study, prostaglandin E, a hormonal activator of adenylate cyclase that has antiproliferative activity in myeloid cells, and cholera toxin, an adenylate cyclase agonist that functions at a postreceptor site by activating the adenylate cyclase stimulatory GTP-binding protein (Gs), were studied for antiproliferative activity in two murine myeloid cell lines. FDC-P1, an interleukin 3 (IL 3)-dependent myeloid cell line and a tumorigenic IL 3- independent subline, FI, were resistant to these antiproliferative agents. The in vitro ability of the "differentiation" agent, sodium butyrate, to reverse their resistance to adenylate cyclase agonists was studied. The antiproliferative action of butyrate involved augmentation of transmembrane adenylate cyclase activity. Increased adenylate cyclase catalyst activity was the primary alteration of this transmembrane signaling group leading to the functional inhibitory effects on leukemia cells, although alterations in regulatory G- proteins appear to play a secondary role.  相似文献   
45.
We analyzed the reactivity and the structure of the VH and VL segments of two IgM monoclonal antibodies (MoAbs) produced by spontaneously in vitro outgrowing cell lines, HBL-2 and HBL-3, established from two acquired immunodeficiency syndrome (AIDS) patients with Epstein-Barr virus (EBV)-negative Burkitt's lymphoma (BL). These B-cell clones were representative of the respective neoplastic parental clones, as determined by immunophenotypic and molecular genetic analysis. The IgM MoAbs were highly specific for the i determinant on red blood cells (cold agglutinins), but bound none of the other eight self and nine foreign antigens (Ags) tested, including those most commonly recognized by natural antibodies or autoantibodies. Structural analysis showed that the IgM MoAb VH segment sequences were 93.5% and 84.2% identical with that of the germline VH4-21 gene, which encodes the vast majority of cold agglutinins that are specific for the i/l carbohydrate Ag and are produced under chronic lymphoproliferative conditions. The HBL-2 MoAb VH4-21 gene segment was juxtaposed with 20P3 and JH6 genes and paired with a V lambda 1 segment, the sequence of which was 95.5% identical to that of the germline Humlv117 gene; the HBL-3 MoAb VH4-21 gene segment was juxtaposed with DXP'1 and JH5 genes and paired with a V lambda 1 segment, the sequence of which was 86.7% identical to that of the germline Humlv1L1 gene. The high degree of conservation of the VH4-21 gene in the human population, the nature of the nucleotide differences in the expressed VH4-21 segments, and the presence of nucleotide substitutions in the HBL-2 and HBL-3 IgM MoAb JH and/or J lambda segments suggested that the MoAb V segments underwent a process of somatic hypermutation. This was formally shown in the HBL-3 MoAb VH segment, by differentially targeted polymerase chain reaction amplification of the HBL-3 MoAb-producing cell genomic DNA. In addition, cloning and sequencing of the genomic DNA from fibroblasts of the same patient whose neoplastic B cells gave rise to the HBL-3 cell line yielded a germline copy of the VH4-21 gene. Thus, the expression of VH4-21 gene products may be involved in a self Ag-driven process of clonal B-cell expansion and selection associated with BL in these AIDS patients.  相似文献   
46.
Apoptosis is the major form of cell death associated with the action of chemotherapeutic agents on tumor cells, and therefore the expression of genes that interfere with apoptosis can have important consequences for the efficacy of therapeutic approaches. Here we show that K562, a chronic myelogenous leukemia (CML) cell line expressing the BCR-ABL fusion protein, are resistant to the induction of apoptosis by a number of agents and conditions. Antisense oligodeoxynucleotides corresponding to the translation start of bcr downregulate bcr-abl protein in these cells and render them susceptible to induction of apoptosis by chemotherapeutic agents or serum deprivation. Expression of a temperature sensitive v-Abl protein reverses the effects of the antisense oligonucleotides, such that the cells remain resistant to apoptosis at the permissive temperature. These data indicate that bcr- abl acts as an anti-apoptosis gene in CML cells and suggests that the effect is dependent on the abl kinase activity in this chimeric protein. Inhibition of bcr-abl to render CML cells susceptible to apoptosis can be combined with therapeutic drugs and/or treatment capable of inducing apoptosis to provide an effective strategy for elimination of these cells.  相似文献   
47.
We report a laparoscopic Nissen fundoplication for gastroesophageal reflux disease (GERD) in a patient with situs inversus totalis (SIT). A 34-year-old man was diagnosed with SIT on performing chest X-ray and abdominal sonography as a routine preoperative investigations. He presented with chronic gastro-esophageal reflux disease (GERD) inadequately controlled by medications. The laparoscopic procedure was performed using five ports placed in a mirror-image configuration and with the patient in the modified lithotomy position. Few technical difficulties were encountered during the operation. The position of the primary surgeon, working between the lower limbs of the patient as in case of standard fundoplication, was considered most prudent position to the success of this case. In SIT, this position provides the least visual disorientation from the reversed abdominal organs. We recommend that preoperative detection of SIT is essential to understand the symptomatology of the patient and for planning of any upper abdominal laparoscopic procedure.  相似文献   
48.
49.

Background:

Haemosuccus pancreaticus (HP) is a rare cause of upper gastrointestinal bleeding. The objective of our study was to highlight the challenges in the diagnosis and management of HP.

Methods:

The records of 31 patients with HP diagnosed between January 1997 and June 2008 were reviewed retrospectively.

Results:

Mean patient age was 34 years (11–55 years). Twelve patients had chronic alcoholic pancreatitis, 16 had tropical pancreatitis, two had acute pancreatitis and one had idiopathic pancreatitis. Selective arterial embolization was attempted in 22 of 26 (84%) patients and was successful in 11 of the 22 (50%). Twenty of 31 (64%) patients required surgery to control bleeding after the failure of arterial embolization in 11 and in an emergent setting in nine patients. Procedures included distal pancreatectomy and splenectomy, central pancreatectomy, intracystic ligation of the blood vessel, and aneurysmal ligation and bypass graft in 11, two, six and one patients, respectively. There were no deaths. Length of follow-up ranged from 6 months to 10 years.

Conclusions:

Upper gastrointestinal bleeding in a patient with a history of chronic pancreatitis could be caused by HP. Diagnosis is based on investigations that should be performed in all patients, preferably during a period of active bleeding. These include upper digestive endoscopy, contrast-enhanced computed tomography (CECT) and selective arteriography of the coeliac trunk and superior mesenteric artery. Contrast-enhanced CT had a high positive yield comparable with that of selective angiography in our series. Therapeutic options consist of selective embolization and surgery. Endovascular treatment can control unstable haemodynamics and can be sufficient in some cases. However, in patients with persistent unstable haemodynamics, recurrent bleeding or failed embolization, surgery is required.  相似文献   
50.
BACKGROUND/AIMS: Management of pancreatic ascites is challenging. The aim of the present study was to study the role of pancreaticogastrostomy in management of pancreatic ascites. METHODOLOGY: Retrospective analysis of twelve operated cases with pancreatic ascites following failed conservative and endoscopic treatment was done for its outcome in terms of morbidity and a successful outcome. Patient data, imaging information and surgical procedure were noted. RESULTS: Four of the 12 patients with leak from the dilated main pancreatic duct had longitudinal pancreaticogastrostomy. The gross edematous jejunum and a shortened mesentery due to sub-acute peritonitis necessitated this surgery. None had recurrence of ascites. Steatorrhea was distinctly absent. None had deterioration of endocrine function. CONCLUSIONS: Longitudinal pancreaticogastrostomy is a viable option in patients with pancreatic ascites and dilated main pancreatic duct especially in those with a shortened mesentery and an edematous small bowel.  相似文献   
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