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51.
PURPOSE: To determine preoperative and intraoperative factors that affect the healing pattern of a myomectomy uterine incision and to estimate the incidence and outcome of postmyomectomy hematoma demonstrated with sonography. METHODS: This observational longitudinal prospective study followed the course of patients diagnosed with at least 1 leiomyomata. Each patent was scheduled for abdominal myomectomy. Preoperative assessments included sonographic measurement of the uterine volume as well as identification of the numbers and sites of the leiomyomata. Detailed operative notes were reported for every patient. Transvaginal sonography was performed for all cases on day 2, day 7, and at 1 month and 3 months postoperatively. The main outcome measure was the occurrence of postoperative hematoma versus preoperative and postoperative factors that possibly affect uterine healing. RESULTS: We found a statistically significant reduction of the uterine volume on follow-up (P < 0.001) of the 169 women enrolled. Hematoma in the myomectomy bed was observed postoperatively in 40 (24%) 28 (17%) and 12 (7%) patients on day 2, day 7, and 1 month, respectively. A preoperative myoma size greater than 110 cm(3), the use of a tourniquet, and the experience of the surgeon were significantly correlated with formation of uterine scar hematomas. CONCLUSIONS: The postoperative sonographic diagnosis of wound hematoma may be used as an indicator of wound healing that is usually complete within 3 months. Use of a tourniquet is frequently associated with hematoma formation. Myomectomy should usually be performed by an experienced surgeon without a tourniquet, using microsurgical principles, especially when the sizes of the leiomyomata exceed 110 cm(3).  相似文献   
52.
The TEPC 15 (T15) clonotype, a putatively germline antibody specificity, does not appear in the neonatal B-cell repertoire until approximately 1 wk of age. This report extends this observation by the demonstration that (a) the T15 clonotype follows similar kinetics of appearance in germfree as well as conventionally-reared mice; (b) maternal influences and genetic background play a minor role in the development of the T15 clonotype since CBFI neonates raised by C57BL/6 or BALB/c mothers acquire the T15 clonotype at the same time in ontogeny as BALB/c neonates; (c) the lack of phosphorylcholine (PC)-specific B cells shortly after birth is reflected in a dearth of PC-binding cells in the neonate as well; and (d) no PC-specifc B cells are found in 19-day fetal liver or in bone marrow until 7 days of life, coincident with their appearance in the spleen. These findings, along with a previous report that PC-specific splenic B cells are tolerizable as late as day 10 after birth, confirm the invariant, late occurrence of the T15 clonotype and support a highly- ordered, rigorously predetermined mechanism for the acquisition of the B- cell repertoire. The results are discussed in light of other studies on the ontogeny of B-cell specificity, and in terms of the implications on the mechanism by which antibody diversity is generated.  相似文献   
53.
We investigated the ability of blood B cells, bone marrow (BM) plasma cells, and terminal leukemic plasma cells (T-PCL) from patients with multiple myeloma (MM) to migrate on extracellular matrix proteins. Hyaluronan (HA), but not collagen type I, collagen type IV, or laminin, promoted migration of MM blood B cells, as determined by time-lapse video microscopy. Between 13% and 20% of MM blood B cells migrated on HA with an average velocity of 19 micron/min, and greater than 75% of MM blood B cells exhibited vigorous cell movement and plasma membrane deformation, as did circulating T-PCL and extraskeletal plasma cells from patients with MM. In contrast, plasma cells obtained from BM of patients with MM lacked motility on all substrates tested and did not exhibit cell membrane protrusions or cellular deformation. MM blood B cells and MM plasma cells from all sources examined expressed the HA- binding receptors receptor for HA-mediated motility (RHAMM) and CD44. On circulating MM B cells, both RHAMM and CD44 participated in HA- binding, indicating their expression ex vivo in an activated conformation. In contrast, for the majority of BM plasma cells in the majority of patients with MM, expression of RHAMM or CD44 was not accompanied by HA binding. A minority of patients did have HA-binding BM plasma cells, involving both RHAMM and CD44, as evidenced by partial blocking with monoclonal antibodies (MoAbs) to RHAMM or to CD44. Despite HA binding by both RHAMM and CD44, migration of MM blood B cells on HA was inhibited by anti-RHAMM but not by anti-CD44 MoAbs, indicating that RHAMM but not CD44 mediates motility on HA. Thus, circulating B and plasma cells in MM exhibit RHAMM- and HA-dependent motile behavior indicative of migratory potential, while BM plasma cells are sessile. We speculate that a subset(s) of circulating B or plasma cells mediates malignant spread in myeloma.  相似文献   
54.
Migliaccio  AR; Bruno  M; Migliaccio  G 《Blood》1987,70(6):1867-1871
The biologic activity of human biosynthetic granulocyte-monocyte colony stimulating factor (GM-CSF) was investigated in serum-free culture of erythroid progenitors derived from adult peripheral blood. The morphology of erythroid bursts and the cloning efficiency of BFU-E under serum-free conditions were similar to those observed in dishes with fetal bovine serum (FBS). For these experiments, progenitor cells were partially purified by Ficoll-Paque density centrifugation, adherence to a plastic surface, and complement-mediated cytotoxicity of Leu-1+ elements. For some studies, blastlike cells were harvested directly from 6-day-old semisolid cultures. In serum-free culture of the light-density cell fraction, biosynthetic erythropoietin (Ep) was sufficient for formation of pure and mixed erythroid colonies whereas GM-CSF was required for granulocyte-monocytic colonies. When adherent and Leu-1+ cells were removed, or when in vitro differentiated blast cells were used as a source of progenitors, neither Ep or GM-CSF alone induced colony formation. In dishes supplemented with both growth factors, erythroid bursts were detected. Although the presence of GM- CSF alone did not induce formation of any colony or clusters, BFU-E were recorded when Ep was added 8 days later, suggesting that BFU-E could be maintained. Terminal maturation of the resulting erythroid bursts was delayed by 8 days. These results provide evidence that GM- CSF acts directly on early erythroid progenitors. Furthermore, they suggest that both Ep and GM-CSF are necessary to start the differentiation process.  相似文献   
55.
56.

Background

We tried to investigate the hair contamination of pet dogs and farm sheepdog with Toxocara eggs in terms of the different sex and age groups in north-west of Iran (Urmia and its suburbs).

Methods

Hair samples were collected from a total of 138 pet and farm sheepdogs from November 2008 to June 2009 in Urmia City and the suburb (West Azerbaijan-Iran) and examined for the presence of T. canis eggs.

Results

T. canis eggs found in 60 samples altogether (pet and shepherd dogs) showed a contamination rate of 36.2%. The number of observed T. canis eggs in each microscope field was varied from 1 to > 400. The age of the dog was found a significant factor to influence the prevalence and intensity of contamination, with 82% of all the eggs recovered from puppies (six months and younger). Additionally, the numbers of eggs in farm sheepdogs were significantly higher than pet dogs (P<0.05).

Conclusion

This report shows that direct contact with T. canis infected dogs, particularly puppies from shepherd dogs, may pose a serious hazard to human. Besides, as they may harbor a considerable number of eggs on their hair, they can contaminate the soil and the environment.  相似文献   
57.

Background

Hadjelia truncata is a nematode that causes lesions in the gizzard lining of pigeons, which may even lead to death. The aim of this study was to introduce Alphitobius diaperinus as a new intermediate host for Hadjelia truncata.

Methods

H. truncata infection was identified in a pigeon flock in Ahvaz City, Khuzestan Province, Iran by performing fecal examination and autopsy. Adult and larval stages of beetles were collected from the litter of pigeon houses, and identified morphologically. The beetle larvae were cultured in a medium, containing feces of the infected pigeons. Nematode larval stages from naturally and experimentally (culturally) infected adult beetles were fed to two groups of pigeons

Results

The collected beetles were identified as Alphitobius diaperinus. Average length and width of the adult beetles were 6.31 mm and 2.88 mm respectively. Infection rates of naturally and experimentally infected beetles with larval stages of the nematode were 66.2% and 45.1% respectively. The adult nematodes collected from gizzards of experimentally infected pigeons were identified as H. truncata. Nematode infection rates in pigeons after feeding the infective larvae collected from naturally and experimentally infected beetles were 44.7% and 32.5% respectively.

Conclusion

A. diaperinus can serve as a natural intermediate host for H. truncata.  相似文献   
58.
Giles  AR; Nesheim  ME; Hoogendoorn  H; Tracy  PB; Mann  KG 《Blood》1982,59(2):401-407
In vitro evaluation of prothrombin complex concentrates in a thrombin generation assay, using DAPA and purified components of the prothrombinase complex, demonstrated significant levels of coagulant- active "phospholipid replacing" activity. Quantification of this activity showed a significant correlation (r = 0.8747, p less than 0.01) with thrombogenicity measured in vivo in a stasis model in rabbits. Extracted lipid material retained full phospholipid replacing activity in the vitro assay. Thin-layer chromatographic characterization confirmed the presence of phospholipids with known coagulant activity in vitro. In vivo, the extracted material was nonthrombogenic but augmented the thrombogenicity of purified factor Xa. Substitution of a synthetic coagulant-active phospholipid (phosphatidylcholine-phosphatidylserine lipid vesicles) for the extracted phospholipid produced a similar augmentation of a factor-Xa- induced thrombogenicity in vivo. It is concluded that the coagulant- active phospholipid content of prothrombin complex concentrates is a major determinant of thrombogenicity but requires the presence of activated clotting factors for its expression in vivo.  相似文献   
59.
Thrombocytopenia is a common serious adverse effect of drug treatment. A variety of in vitro diagnostic techniques to confirm the diagnosis are available, but the majority lack sufficient sensitivity to detect all cases of drug-induced thrombocytopenia. We studied 19 patients with suspected drug-induced thrombocytopenia and demonstrated that platelet- associated IgG (PAIgG) was elevated in all at the time of thrombocytopenia, and PAIgG returned to normal levels as the thrombocytopenia resolved. In the majority of patients, the platelet count rapidly returned to normal after the drug was discontinued; however, in six patients, the thrombocytopenia persisted well beyond the period of time that the offending drug would be expected to be cleared from the blood. In 13 patients, serum obtained after recovery was used to identify the drug responsible for the thrombocytopenia in an in vitro assay. In all cases, the addition of the drug historically associated with the thrombocytopenic episode was associated with an increased binding of IgG to control platelets. For uncertain reasons, the concentration of drug required to increase the in vitro binding of IgG to test platelets was often more than the concentration usually achieved in vivo. Wider application of these techniques may provide better understanding of the clinical characteristics and mechanisms responsible for drug-induce thrombocytopenia.  相似文献   
60.
Type II mixed cryoglobulinemia (MC) is an often progressive vasculitis characterized by circulating cold-precipitable proteins that usually consists of polyclonal IgG and monoclonal IgM kappa with rheumatoid factor (RF) activity. Its etiology is unknown, although recent evidence strongly suggests that hepatitis C virus (HCV) plays a major role. Plasmapheresis, corticosteroids, and cytotoxic drugs have been used in the therapy of MC patients. Recently, favorable results with recombinant interferon-alpha (rIFN alpha) have been reported. To further assess its effectiveness, we studied the effects of natural human interferon-alpha (nIFN alpha), alone and in combination with 6- methyl-prednisolone (PDN), in a prospective, randomized, controlled trial in patients with symptomatic MC. Sixty-five patients were enrolled onto the trial, 52 (80%) of whom presented serum anti-HCV antibodies and specific genomic RNA sequences. Fifteen patients received nIFN alpha (3 MU) intramuscularly (IM) three times weekly, whereas 17 patients also received 16 mg/d of PDN orally on non-IFN days. Moreover, 18 patients received 16 mg/d of PDN only, and 15 were untreated. Treatment was discontinued after 1 year and patients were monitored for 8 to 17 months (mean, 13). A complete response was achieved in eight of 15 patients (53.3%) treated with nIFN alpha and nine of 17 (52.9%) treated with nIFN alpha plus PDN, as compared with three of 18 patients (16.7%) who received PDN only (P < .05) and one of 15 (6.7%) untreated controls (P < .01). Partial response occurred in two of 15 (13.3%) patients treated with nIFN alpha, three of 17 (17.6%) who received nIFN alpha plus PDN, one of 18 (5.5%) who received PDN only, and one of 15 (6.7%) controls. A complete response in six patients (66.7%) was achieved within 3 months in the group that received nIFN alpha plus PDN, as compared with two patients (25%) of those who received nIFN alpha alone (P < .02). In anti-HCV-positive patients, the clinical response occurred in step with reduced or undetectable levels of HCV RNA and transaminase normalization. Quantification of circulating HCV RNA represented a good predictive response marker. The probability of relapse within 3 months after treatment was 100% (three of three patients) and 75% (six of eight patients), respectively, in patients who received PDN alone or nIFN alpha alone as compared with none of those who received nIFN alpha plus PDN (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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