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61.
分析47例骨髓穿刺干抽的临床和病理改变,干抽占同期1319例骨穿的3.6%。根据骨髓细胞的密度和间质纤维增殖的程度,把干抽的原因分为4类:高细胞伴间质细胞增多者19例(42.2%);间质细胞增多者14例(31.1%);高细胞者8例(17.8%)及低细胞者4例(8.9%)。主要疾病为:急性淋巴细胞白血病(25.5%),急性非淋巴细胞白血病(17.0%),慢性白血病(14.9%),骨髓转移瘤(10.6  相似文献   
62.
A new micropore membrane assay for leukocyte migration has been devised. It permits the complete retrieval in monodisperse suspension of functionally intact cells that have traversed the membrane, thus allowing the application of precise, automated techniques, including flow cytometry and electronic particle counting. Hemocytometers may also be used. Direct comparison with 2 different conventional membrane methods showed that the new method performed superiorly. It was also much more economical with regard to time and labor. This technique permitted detection of functional differences between leukocytes isolated from blood in different ways. Data on the duration of concentration gradients in chemotaxis chambers are also presented.  相似文献   
63.
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed.  相似文献   
64.
We have studied 3 cases of sarcoidosis involving the parotid gland by means of fine-needle aspiration cytology (FNAC). The main findings were noncaseating granulomas, multinucleated giant cells (MGCs), and lymphocytes. In one case MGCs contained asteroid bodies and in another case we observed calcium oxalate crystals (COCs) over both stromal fragments and MGCs. Although nonpathognomonic for sarcoidosis, these 2 findings may help in the diagnosis of this condition. However, both are easily overlooked and must be borne in mind when viewing noncaseating granulomas. Sarcoid granulomas displaying COC must be differentiated from foreign-body granulomas. The aforementioned cytological findings must be assessed in conjunction with clinical findings. Nevertheless, in most cases the diagnosis of sarcoidosis is made by exclusion.  相似文献   
65.
Microsurgical epididymal sperm aspiration (MESA) and in-vitrofertilization (IVF) were found to offer limited opportunityfor fatherhood to 45 men with obstructive azoospermia, due principallyto poor embryo implantation. Adequate sperm preparations wereobtained in 46/50 treatment cycles (92%), with the best motilityfound in the caput epididymis in 89% of cases. The mean fertilizationrate was 11.2% and fertilization occurred in 23 cycles (50%),with embryo transfer arising from 12/26 men with was aplasia(CAV), 4/9 with genital tract obstruction (EV) and 7/11 withirreversible vasectomy (VV). The overall implantation rate waslow, 8.7% per embryo transfer (11.7% per 2-3 embryo transfers)and was not improved by Fallopian transfer. There were two pregnancies(4% per cycle), both in the EV group where embryo formationand implatation (2/4, 50% per cycle) were optimum even thoughsperm preparations were paradoxically inferior to the CAV andVV groups. The spermatozoa retrieved in the two successful EVcycles were appreciably blood contaminated. Analysis of the21 failed embryo transfers showed delayed fertilization in 10cycles, cystic fibrosis (CF) mutation or familial disease in7/12 CAV men and the VV men were older (P<0.001). A pregnancywhich miscarried arose from a case of Young's syndrome, a carrierof CF mutation DF508. Male factors could thus be implicatedin the high embryo wastage of MESA cycles and might also beinfluencing implantation in other IVF procedures. Where feasible,male reconstructive surgery is preferable unless fertilizationcan be improved, possibly by speedier retrieval techniques orby permitting sperm capacitation in vitro, but probably moreeffectively by micro-assisted insemination.  相似文献   
66.
Rhabdomyoblasts demonstrating immunoreactivity for muscle-specific actin, desmin, and myoglobin were identified in smears obtained by aspiration from a large retroperitoneal mass in a 14-mo-old girl. Following a tentative diagnosis of a rhabdomyogenous neoplasm, retroperitoneal exploration and adrenalectomy demonstrated a stromal poor neuroblastoma with extensive rhabdomyogenous differentiation. The presence of a subpopulation of rhabdomyoblasts was not diagnostic of rhabdomyosarcoma when obtained by fine-needle aspiration from a retroperitoneal tumor composed predominantly of primitive small round cells.  相似文献   
67.
We have analyzed 245 transplant aspirative cytologies (TACs) from 96 renal allograft patients. TACs were divided in two chronological groups: Early (TACs performed during the first 3-mo post-transplantation) and late (TACs performed after the third month post-transplantation), in order to assess the effect of allograft tolerance on TAC features. Both morphological and immunocytochemical aspects were evaluated, including CD4, CD8, IL2-R, and HLA-DR immunolabeling. A final diagnosis for each case of allograft dysfunction was achieved by other independent diagnostic means. Four diagnostic groups were considered in the present study: acute rejection (AR), chronic rejection (CR), acute tubular necrosis (ATN), and Cyclosporin A toxicity (CsA-T). In addition, a control group (C) was established from patients with stable allograft function. We found that immunocytochemical analysis of TACs is particularly helpful in the diagnosis of late allograft dysfunction, a time period when the simple cytological study of renal infiltrate is not informative enough to help take therapeutic decisions.  相似文献   
68.
Epithelioid gastrointestinal stromal tumors (GISTs) may cause significant diagnostic confusion on fine-needle aspiration (FNA) with carcinomas, neuroendocrine tumors, and melanoma, particularly when metastatic. This study characterizes the cytologic features of nine cases of epithelioid GISTs that were obtained by computerized tomographic guidance in five, by endoscopic ultrasound in three, and from an excised liver tumor in one. Six cases presented as liver masses, one as a perisplenic mass, one as an abdominal mass, and one as a gastric mass. The aspirates revealed mainly single or small clusters of epithelioid cells with a moderate amount of granular to clear cytoplasm, small uniform nuclei with mild to marked nuclear envelope irregularities. Binucleation and intranuclear inclusions were frequent findings. Collagenous stroma was seen in most cases. In three cases, a neuroendocrine tumor was the initial diagnosis. Immunocytochemical staining for c-kit (CD117) was performed on cellblocks in six cases and was positive in five cases. On the subsequent surgical specimen, CD117 was positive in the c-kit-negative cytology case. The diagnosis of GIST should be considered in aspirates of the gastrointestinal tract, liver, mesentery, or abdominal wall mass lesions when epithelioid cells are the predominant cell type. Ancillary studies such as immunohistochemical stains are usually helpful in making a definitive diagnosis.  相似文献   
69.
To evaluate the clinical applicability of galectin-3 and CD44 variant 6 (CD44v6) immunostaining in fine-needle aspiration cytology (FNAC) of thyroid follicular tumors, 79 cytological specimens (35 follicular carcinomas and 44 follicular adenomas) were studied. The positive rates of galectin-3 and CD44v6 were 89 and 74% in follicular carcinoma, respectively, and 25 and 30% in follicular adenoma, respectively. There were no significant correlations between the expression of galectin-3 or CD44v6 in follicular carcinoma and characteristics such as capsular invasion, vascular invasion, metastasis, or tumor size. Positive staining of either galectin-3 or CD44v6 resulted in a diagnostic sensitivity of 97% and a specificity of 52% for follicular carcinoma among follicular tumors. Immunostaining of galectin-3 or CD44v6 using cytological specimens can provide independent information on conventional morphological findings of cytology to distinguish follicular carcinoma from adenoma.  相似文献   
70.
Large B-cell lymphomas (LBCLs) have significant false-negative results when immunophenotyped by flow cytometry (FC). To clarify the role fine-needle aspiration (FNA) in reducing this false-negative rate, 28 cases ultimately diagnosed as LBCL that had FNA as part of the workup and a negative FC were identified. We examined their clinical and cytologic features, in comparison with cases of LBCL with FNAs that were positive by FC. In 24/28 FC-negative cases (86%) a cytologic diagnosis of suspicious or positive for malignancy was rendered. We conclude that cytologic analysis is more sensitive than FC in the diagnosis of malignancy in FNA of LBCL, particularly in aspirates with low cellularity and/or low viability. Examination of cytospin preparations of the actual material analyzed by FC may provide an indication that an FC result is falsely negative. It is important to recognize the potential of false-negativity by FC of LBCLs when interpreting FNAs with features suggesting lymphoma.  相似文献   
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