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41.
Large-cell variants are uncommon in mantle cell lymphoma (MCL). Here we describe the pathologic and clinical findings in five patients with large-cell lymphoma related to MCL (L-MCL), and compare them to a group of classic small-cell MCL (s-MCL) cases. Histologically, the MC origin of the large cells was evinced by their association with a small mantle cell component in the same tissue, or their distribution in a classic mantle zone pattern, or their development in a patient with previous s-MCL. The large cells were either pleomorphic mantle cells (case 1) or transformed blast-like cells (cases 2–5). The median nuclear diameter, median nuclear area and proliferation index of L-MCLs and s-MCLs, were statistically different. Immunophenotypic characterization of four specimens of L-MCL and 10 of s-MCLs with a large panel of antibodies showed the classic findings of MCL, i.e. the IgM+ D+/?, CD5+, CD10?, CD23? phenotype in all cases except two (one CD5? and one CD23+), and the association with a loose follicular dendritic cell network. Two of four L-MCLs and 5/10 s-MCLs demonstrated rearrangements of the bcl-1 gene by Southern blot or by polymerase chain reaction (PCR); 2/4 L-MCLs and 1/9 s-MCLs had p53 mutations on single-strand conformation polymorphism analysis; none of the 14 specimens showed rearrangement of bcl-2 by PCR or bcl-6 and c-myc by Southern blot. All patients with ‘transformed’ histology (versus 37% of all others) died of lymphoma; their survival (15–18 months; median 17) was much shorter than that of all the others (28–117+ months; median 43) (P = 0.0035). All three patients with p53 anomalies, two of whom had tumours with transformed histology, died of their disease in a short time (15, 18 and 28 months). In contrast, the presence of bcl-1 rearrangements did not have prognostic implications. This study documents the existence of large-cell variants of MCL and the poor prognosis associated with the ‘transformed’ cytologic type and/or p53 abnormalities.  相似文献   
42.
Four new recurring translocations in non-Hodgkin lymphoma   总被引:13,自引:0,他引:13  
The identification of recurring chromosomal translocations has provided clues to the gene regions important in lymphoma development. Among 157 patients with non-Hodgkin lymphoma studied by cytogenetic analysis, four new recurring translocations have been identified--t(8;9) (q24;p13), t(11;18)(q21;q21), t(14,15)(q32;q15), and an unbalanced translocation giving rise to der(22)t(17;22) (q11;p11). Each translocation appeared twice. The t(11;18) was the only karyotypic abnormality in the two patients with it, and the t(14;15) was the sole karyotypic abnormality in one patient. All translocations were found in B-cell malignancies and were associated with both nodal and extranodal disease. Among the regions affected, only the immunoglobulin heavy- chain gene MYC, and BCL2, have thus far been associated with lymphoma. The breakpoint sites identified by these translocations warrant further investigation at the molecular level.  相似文献   
43.
Clinical Oral Investigations - The aim of this study was to investigate bone turnover alterations after alendronate (ALD) withdrawal and its influence on dental implants osseointegration. Seventy...  相似文献   
44.
We report a novel chromosome translocation--t(2;5)(p23;q35) or its variant, t(2;5;13)(p23;q35;q12)--in 3 patients with peripheral T-cell lymphoma. All 3 were female children who had peripheral lymphadenopathy without organomegaly and underwent complete remission with or without chemotherapy. Their tumors were characterized histologically by predominant large cells, at times showing phagocytosis, and immunologically by peripheral T-cell phenotype and expression of Ki-1 antigen and epithelial membrane antigen (EMA). Since the same translocation has been reported in the literature in 4 patients with malignant histiocytosis (MH), and our patients had histologic features suggestive of that disease, it is likely that many tumors previously interpreted as MH are actually phagocytic large T-cell lymphoma carrying this translocation.  相似文献   
45.
46.
The posttransplantation lymphoproliferative disorders (PT-LPDs) are a morphologically heterogeneous group of Epstein-Barr virus (EBV)-driven lymphoid proliferations of varying clonal composition. Some PT-LPDs regress after a reduction in immunosuppression, while others progress in spite of aggressive therapy. Previously defined morphologic categories do not correlate with clonality, and neither morphology nor clonality has reliably predicted the clinical behavior of PT-LPDs. We investigated 28 PT-LPD lesions occurring in 22 patients for activating alterations involving the bcl-1, bcl-2, c-myc, and H-, K- and N-ras proto-oncogenes and for mutations involving the p53 tumor suppressor gene. We correlated the results of these studies with the morphology of the lesions, their clonality based on Ig heavy and light chain gene rearrangement analysis, and the presence and clonality of EBV infection. We found that the PT-LPDs are divisible into three distinct categories as follows: (1) plasmacytic hyperplasia: most commonly arise in the oropharynx or lymph nodes, are nearly always polyclonal, usually contain multiple EBV infection events or only a minor cell population infected by a single form of EBV, and lack oncogene and tumor suppressor gene alterations; (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma: may arise in lymph nodes or various extranodal sites, are nearly always monoclonal, usually contain a single form of EBV, and lack oncogene and tumor suppressor gene alterations; and (3) immunoblastic lymphoma or multiple myeloma: present with widely disseminated disease, are monoclonal, contain a single form of EBV, and contain alterations of one or more oncogene or tumor suppressor genes (N-ras gene codon 61 point mutation, p53 gene mutation, or c-myc gene rearrangement). The PT-LPDs are divisible into three categories exhibiting distinct morphologic and molecular genetic characteristics. Alterations involving the N-ras and c-myc proto- oncogenes and the p53 tumor suppressor gene may play an important role in the development and/or progression of the PT-LPDs.  相似文献   
47.
We report the association in a 10-year-old boy of an angiomatoid malignant fibrous histiocytoma (AMFH) of the left thigh with ipsilateral inguinal, pelvic and extensive retroperitoneal lymphadenopathy, and severe systemic manifestations. These include growth retardation, fever, severe anemia, hypergammaglobinemia, and hypoalbuminemia. At ultrastructural level the tumor was characterized by an abundance of myofibroblasts, occasional histiocytes, and small vessels with marked reduplication of the basal lamina. Biopsies of the inguinal and abdominal lymph nodes showed follicular hyperplasia and massive plasmacytosis indistinguishable from Castleman's disease (giant lymph node hyperplasia) of plasma cell type. The radical surgical excision of the primary tumor in the thigh resulted in the disappearance of the abdominal lymphadenopathy and a marked reduction in size of the pelvic lymph nodes with marked decrease of the gammaglobulins, thus proving that the nodal lesions were the expression of a reactive process to the tumor rather than a coincidental independent lymphoproliferative disorder. Retroperitoneal and pelvic node dissection ivas performed I year after the radical excision of the thigh tumor because of persistent pelvic lymphadenopathy and failure of serum immunoglobulins M and A to return to normal level, with, a recent peak of IgA to twofolds that of normal value. Metastatic AMFH was found in the three pelvic nodes. One month postoperatively IgA returned to near normal level whereas IgM remained slightly elevated.  相似文献   
48.
A randomized clinical trial of combination chemotherapy for patients who relapsed following primary radiation therapy for Hodgkin's disease was conducted from 1975 to 1981 by the Cancer and Leukemia Group B (CALGB). One hundred thirteen patients were prospectively randomized to receive 12 cycles of either CVPP (CCNU, vinblastine, procarbazine, and prednisone), ABOS (bleomycin, vincristine [Oncovin; Lilly, Indianapolis], doxorubicin [Adriamycin, Adria Laboratories, Columbus, Ohio], and streptozotocin), or alternating cycles of CVPP and ABOS. The median length of observation for patients in this report is 4 years. Toxicities of the three treatment programs were primarily hematologic. Frequencies of complete response were 72% for CVPP, 70% for ABOS, and 82% for CVPP/ABOS (P = .37). Females and patients who had nodular sclerosing disease at initial diagnosis had significantly higher complete response rates. The 5-year disease-free survival for the complete responders was 55%; the 5-year overall survival was 60%. There were no significant differences among the treatments on disease-free survival (P = .78) or overall survival (P = .18). Age under 40 years was the only significant positive prognostic factor for disease-free survival (P = .095) and overall survival (P = .003). This study demonstrates no statistically significant advantage for alternating cycles of combination chemotherapy in affecting complete response frequency, disease-free survival, or overall survival as compared with therapy with CVPP or ABOS alone. However, the power to detect differences in these outcome parameters is somewhat limited by the sample sizes.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
49.
Histopathologic slides of 368 cases collected from 16 institutions around the world for the Fifth International Chromosome Workshop were independently reviewed by a group of five hematopathologists consisting of two Americans and three Japanese. Agreement rates of their diagnoses using the Working Formulation (WF) for non-Hodgkin's lymphomas were studied. A modified classification scheme of the WF was used in order to define cytologic subtypes more specifically, enabling 65 possible diagnostic choices. Data analyses by computer revealed that at least four out of five diagnostic agreements were observed in 290 cases (78.9%). Similar agreements were observed in more than 80% of the cases for most of the categories of the WF, excepting diffuse small cleaved (73.3%), diffuse mixed (64.2%), diffuse large cell (76.5%), and immunoblastic lymphoma (70.2%). Agreement rates between American and Japanese pathologists did not demonstrate statistically significant differences against expected values. It was concluded that the WF was a reliable and useful classification system for multi-institutional as well as international projects, although refinements may be necessary in some categories for better diagnostic agreement.  相似文献   
50.
Nineteen renal allograft recipients developed B-cell lymphoproliferative diseases. Clinically there were two groups: a) young patients (mean age, 23 years) who presented soon (mean, 9 months) after transplantation or antirejection therapy with fever, pharyngitis, and lymphadenopathy resembling infectious mononucleosis, and b) older patients (mean age, 48 years) who presented later (mean, 6 years) after transplantation with localized tumor masses. Histologically, the diseases were classified as polymorphic diffuse B-cell hyperplasia (PDBH) or polymorphic B-cell lymphoma (PBL). Immunologic cell typing revealed either polyclonal or monoclonal B-cell proliferations. Malignant transformation of polyclonal proliferations in two patients was suggested by the finding of clonal cytogenetic abnormalities. Epstein-Barr virus (EBV) specific serology, staining of biopsy specimens for the Epstein-Barr nuclear antigen, and EBV DNA molecular hybridization studies implicated EBV as the cause of both PDBH and PBL. Acyclovir, an antiviral agent that blocks EBV replication in vitro, inhibited oropharyngeal shedding of EBV and caused complete remission in four patients with polyclonal B-cell proliferations. The monoclonal tumors were acyclovir resistant. We suggest that surgical treatment, radiotherapy, or chemotherapy may be more appropriate therapy in selected patients with acyclovir resistant tumors. Therapeutic decisions require not only documentation of the viral etiology of these tumors, but also immunologic and cytogenetic analysis to determine the stage of tumor evolution in individual patients.  相似文献   
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