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排序方式: 共有2174条查询结果,搜索用时 15 毫秒
91.
Comparison of genetic probe with immunophenotype analysis in lymphoproliferative disorders: a study of 87 cases 总被引:4,自引:0,他引:4
Henni T; Gaulard P; Divine M; Le Couedic JP; Rocha D; Haioun C; Henni Z; Marolleau JP; Pinaudeau Y; Goossens M 《Blood》1988,72(6):1937-1943
We examined 91 specimens (from 87 patients) for the expression of B- cell- and T-cell-associated differentiation antigens and rearrangements of the Ig and beta-chain of the T-cell (beta-TCR) genes. Of these, 74 were representative of various histologic subtypes of non-Hodgkin's lymphoma and related disorders, 11 of Hodgkin's disease, and 6 of reactive lymphoid hyperplasia. An Ig gene clonal rearrangement correlated to a monotypic (kappa/lambda) phenotype in 32 of 33 histologically defined lymphoma samples. The genotypic analysis also confirmed clonality in six of seven malignant diffuse lymphomas that were nonmonotypic but expressed pan-B antigens; in four, more than one clone was detected within individual tumors. A beta-TCR clonal rearrangement was found in 19 of 19 tumor samples considered as malignant T-cell lymphoma on the basis of histopathology and of the CD3- positive phenotype of tumoral cells, and in two cases of CD3-positive lymphomatoid disorders. A loss of pan-T antigens (CD7, CD5, CD2, CD4/CD8) was observed in all but three of these CD3-positive samples. Such an incomplete T-cell phenotype always correlated to the presence of a monoclonal process as revealed by genotypic analysis. DNA analysis was the only way to demonstrate clonality in other samples with either a polymorphous (partial involvement, pseudolymphoma, angioimmunoblastic lymphodenopathy [AILD]) or an undifferentiated (large cell anaplastic) phenotype. It is concluded that although in the majority of cases immunophenotyping alone provides criteria adequate for the diagnosis of lymphoid malignancy, in some, particularly polymorphous or large cell anaplastic processes, genetic probe analysis was additionally discriminative. 相似文献
92.
Barry J. Iacopetta Richie Soong Anthony K. House Richard Hamelin 《The Journal of pathology》1999,187(4):428-432
The replication error phenotype (RER+) represents an important new form of genetic alteration characterized by widespread instability in repetitive nucleotide sequences. The aim of this study was to compare the features of RER+ gastric tumours with those of RER+ colonic tumours. RER status was determined by analysis of size alterations in the BAT-26 mononucleotide repeat microsatellite. Twelve of 121 (10 per cent) gastric carcinomas from a low-incidence region were found to be RER+. BAT-26 instability was associated with tumours showing an absence of nodal invasion (p = 0·009) and with a trend for improved prognosis. These tumours were more frequent in older, female patients. Frameshift mutations in mononucleotide repeat sequences within the transforming growth factor-β receptor II (RII), insulin-like growth factor II receptor (IGFIIR), and BAX genes were observed in 83, 33, and 25 per cent, respectively, of RER+ tumours. Only 1/12 (8 per cent) RER+ tumours contained a p53 gene mutation compared with 29/109 (27 per cent) RER− tumours. RER+ gastric carcinomas therefore share several important features with RER+ colonic tumours, including less frequent nodal invasion, improved prognosis, a similar frequency of mutation in growth control genes containing repetitive nucleotide sequences, and a low frequency of mutation of the p53 tumour suppressor gene. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
93.
Five patients with optic neuropathy, four vascular and one demyelinating, are described who each complained of an unusual symptom. Bright flashes of light (phosphenes) occurred in the affected eyes and were evoked by sudden unexpected sounds. Movement of the eye alone did not reproduce the symptom. In all patients the phenomenon was sufficiently prominent to interfere with sleep and was the main complaint of one patient. An anticonvulsant (phenytoin) greatly reduced the frequency and intensity of the phosphene in one patient. 相似文献
94.
Macon WR; Williams ME; Greer JP; Hammer RD; Glick AD; Collins RD; Cousar JB 《Blood》1996,87(4):1474-1483
Natural killer (NK)-like T cells are major histocompatibility complex- unrestricted cytotoxic T cells that are surface CD3-positive, express NK-cell antigens, and rearrange their T-cell receptor. Most neoplasms arising from this T-cell subpopulation have been a chronic lymphoproliferative disease referred to as T-large granular lymphocyte (LGL) leukemia. Only 10 NK-like T-cell lymphomas have been described in detail previously; this study presents the clinicopathologic features of six others and distinguishes these lymphomas from T-LGL leukemia. All patients presented with B-symptoms and often had marked hepatosplenomegaly without significant peripheral lymphadenopathy. Four of the six patients were immunosuppressed. All had CD3, CD8, CD56- positive tumors, presumably of hepatosplenic (n = 3), intestinal (n = 1), pulmonary (n = 1), or nodal (n = 1) origin. Three patients had lymphomatous bone marrow infiltrates, and four had peripheral blood involvement by neoplastic large lymphocytes, some of which had a blastic appearance or resembled virocytes. Azurophilic granules, ultrastructurally corresponding to cytoplasmic dense core and/or double density granules, were seen in all cases. T-cell clonality was shown in five tumors by Southern blot analysis, and three had abnormal karyotypes. Two untreated patients died 20 days after presentation, and three patients who received combination chemotherapy died within 5 months of presentation. One patient remains in complete remission 22 months after treatment. These findings suggest NK-like T-cell lymphomas are aggressive, are clinicopathologically distinct from T-LGL leukemia, and should be in the differential diagnosis of extranodal T-cell lymphoproliferations, including those in immunosuppressed patients. Furthermore, the LGL morphology, phenotype, and tissue distribution of some NK-like T-cell lymphomas suggest they arise from thymic- independent T cells of the hepatic sinusoids and intestinal mucosa. 相似文献
95.
High-dose intravenous gammaglobulin in alloimmunized platelet transfusion recipients 总被引:1,自引:1,他引:1
High-dose intravenous gammaglobulin (polyvalent immunoglobulin G) has been shown to be of benefit in some patients with immune thrombocytopenic purpura (ITP), possibly by producing reticuloendothelial system blockade. We studied this approach in patients refractory to random donor platelet transfusion using an IV IgG preparation manufactured by the Swiss Red Cross. Eleven adult patients with acute leukemia received either 0.4 g IgG/kg/d intravenously X five days (four patients) or 0.6 g/kg/d X five days (seven patients). All patients had high levels of lymphocytotoxic antibody and poor responses to random donor platelets. Except for mild headaches in two patients, there were no side effects related to the IgG infusions. All patients had significant elevations of serum IgG on the day after completion of treatment. Either random donor or partially HLA-matched platelet transfusions were administered the day after and, in some cases, during the IgG therapy. No patient had an improvement in one hour posttransfusion platelet count increments. Two additional patients received pooled platelet concentrates incubated for 30 minutes at 37 degrees C with IgG at a final concentration of 3 g% prior to transfusions. These results indicate that high-dose IgG, an extremely expensive treatment, cannot be recommended for alloimmunized adults with leukemia. 相似文献
96.
To determine the transmissibility of human T-lymphotropic virus types I and II (HTLV-I and HTLV-II) via transfusion, persons who, from 1983 to 1989, received blood components donated by persons who subsequently tested anti-HTLV-I-positive were evaluated. It was found that 16 (30%) of 54 evaluable recipients of transfused cellular components became infected with one of the HTLVs: 8 had HTLV-I and 8 had HTLV-II. Forty percent of platelet recipients and 28 percent of red cell recipients acquired infection. The rate of transmission of HTLV-I and HTLV-II was significantly correlated with storage age of red cell units prior to transfusion: 47 percent for red cells stored < or = 14 days and 0 for red cells stored > 14 days (p < 0.01). Multiple confirmatory serologic tests performed in 46 anti-HTLV-I enzyme immunoassay-negative recipients revealed that HTLV infection could not be excluded in 3 recipients of blood components from HTLV-II-infected donors. Polymerase chain reaction established HTLV-II infection in one recipient, and the other two recipients could not be classified with respect to HTLV infection status. It appears that some HTLV-II-infected transfusion recipients will not be detected by existing HTLV-I antigen-based reagents. If it is deemed necessary to initiate or continue look-back programs to detect transfusion transmission of HTLV-II infection, it is suggested that the current testing algorithm be modified in selected cases. 相似文献
97.
98.
Queenan JT Jr; Veeck LL; Toner JP; Oehninger S; Muasher SJ 《Human reproduction (Oxford, England)》1997,12(7):1573-1576
In-vitro fertilization patients (n = 15) at risk of ovarian
hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day
of human chorionic gonadotrophin administration and 25 or more follicles of
intermediate or large size) underwent aspiration of all follicles and
cryopreservation of all fertilized oocytes at the pronuclear stage.
Patients were monitored for up to 2 weeks post- retrieval. Subsequent
transfer of cryopreserved-thawed embryos was performed in programmed cycles
using exogenous oestrogen and progesterone for endometrial preparation. Two
patients (13%) developed OHSS necessitating hospitalization and vaginal
aspiration of ascitic fluid. Two other patients (13%) developed moderate
OHSS requiring ascitic fluid vaginal aspiration in the office setting, with
dramatic improvement of the condition. Subsequent transfer of
cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per
transfer and ongoing or delivery rates of 42 and 67% per transfer and per
patient respectively. By eliminating pregnancy potential with
cryopreservation of all prezygotes and examining the pregnancy potential
with subsequent cryopreserved-thawed transfers, it is concluded that OHSS
is reduced, but not eliminated for patients at risk. Subsequent transfer of
cryopreserved-thawed prezygotes in a programmed cycle with exogenous
steroids yields an excellent pregnancy rate.
相似文献
99.
Supriya Srivastava Bhavin Thakkar Khay Guan Yeoh Khek Yu Ho Ming Teh Richie Soong Manuel Salto-Tellez 《Virchows Archiv : an international journal of pathology》2015,466(5):541-548
In the development and progression of hepatocellular carcinoma, tumor hypoxia plays an important role, as does activation of the Wnt pathway. The aim of this study was to characterize the expression and interrelationship between hypoxia and Wnt-pathway-associated proteins as prognostic factors for hepatocellular carcinoma. Expression of HIF-1α, CA-IX, E-cadherin, β-catenin, and Ki-67 was assessed by immunohistochemistry in 179 primary hepatocellular carcinoma cases. Univariate and multivariate analyses were performed to assess the relationship between the clinicopathological factors, protein expression, overall survival (OS), and recurrence-free survival (RFS). By univariate analysis, tumor stage, size, satellitosis, and vascular invasion were confirmed as prognostic factors for worse OS and RFS. High expression of HIF-1α, CA-IX, β-catenin, Ki-67, and E-cadherin was observed in 60, 15, 64, 8, and 64 % of tumors, respectively, and this was significantly associated with poor OS. CA-IX, HIF-1α, and E-cadherin were independent predictors of poor prognosis. We stratified 169 patients into four groups according to the expression level of hypoxia and Wnt pathway markers. The group with high expression of both hypoxia and Wnt-pathway-associated proteins showed worst OS. The poor survival of this group was also significant in patients with early stage disease and tumor size of less than 5 cm (p?<?0.05). We identified a subgroup of hepatocellular carcinoma patients with high expression of both hypoxia and Wnt pathway proteins and found this predictive of poor survival. The therapeutic options for this group might need to be revisited. 相似文献
100.
Kuo-Yang Huang Kuen-Yi Chien Yin-Chun Lin Wei-Min Hsu I-Kai Fong Po-Jung Huang Yuan-Ming Yueh Richie Ruei-Chi Gan Petrus Tang 《Parasitology research》2009,104(4):927-933
Trichomoniasis caused by Trichomonas vaginalis is the most common sexual transmitted infection in the world. The 170-MB genome of this protozoan contains 60,000 genes,
the largest number of genes ever identified in protozoan. High-throughput expression sequenced tag analysis showed that at
least 4,000 genes were expressed in the trophozoite stage. In the present study, we use two-dimensional electrophoresis combined
with matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis to profile, identify, and characterize
proteins expressed in the trophozoite stage of T. vaginalis. A total of 247 spots representing 164 different proteins were identified. The identified proteins with known sequence or
motif/domain homologies were further classified into groups according to their biological functions. Among them, proteins
related to carbohydrate metabolism represented the most abundant category in the T. vaginalis proteome. This study presented the most extensive proteomic analysis of T. vaginalis to date and provided a reference proteome database for future comparative proteomic studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献