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61.
Werner M Mattis A Aubele M Cummings M Zitzelsberger H Hutzler P Höfler H 《Virchows Archiv : an international journal of pathology》1999,435(5):469-472
The 20q13 region harboring recently described putative oncogenes is frequently amplified in invasive ductal carcinoma (IDC).
The aim of this study was to examine the 20q13 copy number in intraduct hyperplasia (IH), atypical duct hyperplasia (ADH),
and ductal carcinoma in situ (DCIS) adjacent to IDC. In 5 patients, comparative genomic hybridization (CGH) after laser microdissection
revealed 20q13 amplification in four of five cases of IH, in all of three cases of IH with atypia, all five of DCIS, and all
five of IDC. Fluorescence in situ hybridization (FISH) confirmed the amplification at 20q13.2 in IH in the two specimens analyzed.
The amplification rate, however, was higher in DCIS and IDC. In phenotypically normal ductal epithelium normal values were
found for 20q13 copy number by FISH (n=2) and CGH (n=5). Although the number of cases presented here is small, our results suggest that mutations in the 20q13.2 region in IH
may be associated with accelerated proliferation and hyperplasia of the ductal epithelium. Progression to DCIS and ICD is
accompanied by a further increase in the 20q13.2 copy number.
Received: 17 March 1999 / Accepted: 22 June 1999 相似文献
62.
Classification of Breast Masses Using Selected Shape,Edge-sharpness,and Texture Features with Linear and Kernel-based Classifiers 总被引:2,自引:0,他引:2
Breast masses due to benign disease and malignant tumors related to breast cancer differ in terms of shape, edge-sharpness, and texture characteristics. In this study, we evaluate a set of 22 features including 5 shape factors, 3 edge-sharpness measures, and 14 texture features computed from 111 regions in mammograms, with 46 regions related to malignant tumors and 65 to benign masses. Feature selection is performed by a genetic algorithm based on several criteria, such as alignment of the kernel with the target function, class separability, and normalized distance. Fisher's linear discriminant analysis, the support vector machine (SVM), and our strict two-surface proximal (S2SP) classifier, as well as their corresponding kernel-based nonlinear versions, are used in the classification task with the selected features. The nonlinear classification performance of kernel Fisher's discriminant analysis, SVM, and S2SP, with the Gaussian kernel, reached 0.95 in terms of the area under the receiver operating characteristics curve. The results indicate that improvement in classification accuracy may be gained by using selected combinations of shape, edge-sharpness, and texture features. 相似文献
63.
Fernando Carlos Schmitt Maria Jos Bento Isabel Amendoeira 《Diagnostic cytopathology》1995,13(4):347-351
We describe a method of immunocytochemically assessing estrogen receptor (ER) status on alcohol-fixed smears obtained by fine-needle aspiration (FNA) from breast cancer patients, using a commercially available monoclonal antibody (1D5) with microwave oven processing. A series of 31 cases of aspirates from breast cancer were analysed and the results were compared with assessment by ER immunocytochemical assay using the same procedure on formalin-fixed tissue and with assessment by ER-ICA assay on frozen sections. The results were scored semiquantitatively using a five grade scoring system. Of the 31 cases examined, 21 were positive at least by two methods and 10 were negative for all three determinations. The results obtained in the ER immunocytochemical assay on aspirates and paraffin-sections using the antibody 1D5 and those obtained on frozen sections using the antibody H222 were closely similar. In only one case was it not possible to interpret the reaction in the cytological specimen because there was a strong background in the smear. In general, we obtained more intense positivity with the antibody 1D5 in aspirates and formalin-fixed material than with the antibody H222 in frozen sections. The scoring results of the three methods were almost identical. We conclude that the application of ER method on alcohol-fixed smears will eliminate the need for using a special fixation procedure and will provide several advantages, such as: improvement in morphological concomitant analysis, utilization whenever malignancy is found without necessity to re-aspirate the patient, and adequacy of archival material. © 1995 Wiley-Liss, Inc. 相似文献
64.
A computer model was designed as a relational database to assess breast cancer screening in a cohort of women where the growth and development of breast cancer originates with the first malignant cell. The concepts of thresholds for growth, axillary spread, and distant sites are integrated. With tumor diagnosis, staging was performed that includes clinical and sub-clinical states. The model was parameterized to have staging characteristics similar to data published by the Surveillance, Epidemiology, and End-Results (SEER) Program. Validation was accomplished by comparing simulated staging results with non-SEER sources, and simulated survival with independent clinical survival data. 相似文献
65.
Zhang Y Siebert R Matthiesen P Harder S Theile M Scherneck S Schlegelberger B 《Virchows Archiv : an international journal of pathology》2000,436(3):271-275
For the first time, combined immunophenotyping and fluorescence in situ hybridization (FISH) technique according to the ”fluorescence
immunophenotyping and interphase cytogenetics as a tool for investigation of neoplasms” (FICTION) technique have been successfully
applied in solid tumors. Thus, we were able to visualize the antigen expression of cells with chromosomal deletions of a tumor
suppressor region directly. In six breast carcinoma cell lines, we investigated the correlation between estrogen receptor
(ER) expression status and deletions of the estrogen receptor gene (ESR). To screen for deletions of the ESR gene, dual-color
FISH was performed with a YAC (yeast artificial chromosome) probe containing the ESR gene and, as internal control, with a
centromeric probe of chromosome 6. Deletions of the ESR gene were detected in four of six cell lines. For direct comparison
of ER expression with the copy number of the ESR gene at the single cell level, immunophenotyping with mouse anti-human ER
antibody was combined with FISH with the YAC probe containing the ESR gene according to the FICTION technique. There was no
correlation between lack of or reduced ER expression and deletions of the ESR gene. One cell line with deletions of the ESR
gene did express ER on the protein level, while another cell line without a deletion did not. Cells with deletions of the
ESR gene were either ER expression positive or negative. The staining intensity of ER expression was not associated with the
copy number of the ESR gene. Thus, this FICTION study unequivocally shows that deletions of the ESR gene are not the major
cause of absent or reduced ER expression in breast carcinoma cell lines.
Received: 6 September 1999 / Accepted: 14 September 1999 相似文献
66.
67.
Klaus Hamprecht Matthias Vochem Andrea Baumeister Michael Boniek Christian P Speer Gerhard Jahn 《Journal of virological methods》1998,70(2):167-176
Human cytomegalovirus (HCMV) DNA can be detected in different compartments of human milk. A protocol for the preparation of milk whey free of fat and cells for the detection of human cytomegalovirus (HCMV) by nested PCR is presented. This is based upon the experience of the separation of more than 200 milk specimens of healthy seropositive breast feeding mothers. HCMV DNA could be detected in freshly centrifuged and filtrated milk whey specimens without contamination by cellular DNA. In limiting dilution experiments using HCMV plasmid DNA, the effect of different DNA extraction procedures from native milk and milk whey on the detection limit of cytomegaloviral DNA was demonstrated. About 200 viral genome equivalents/ml in milk whey or native milk were detectable by classical organic phenol/chloroform extraction or a spin column method, respectively. The detection of viral DNA in milk cells depended on a minimum number of milk cells (105–2×105) available for DNA extraction. In contrast to the findings of cytomegaloviral DNA in native sera or plasma of immunosuppressed patients we failed to amplify low level viral DNA from native breast milk by nested PCR due to an inhibition of Taq polymerase by lipid components. Finally, the course of cell associated and cell free DNAlactia was monitored. Analyzing sequential milk specimens, in some cases the presence of HCMV DNA in colostrum could be demonstrated. DNAlactia of milk cells and whey was partially discordant. Onset (week 1–4 after delivery) and duration (2 weeks up to more than 3 months) of DNAlactia showed distinct individual patterns. The methods described, allow further analysis of the mechanisms involved in the postnatal HCMV transmission by breast feeding seropositive mothers. 相似文献
68.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer. 相似文献
69.
Joan McCutcheon Rosemary A. Walker 《Virchows Archiv : an international journal of pathology》1987,410(5):369-374
Summary The significance of demonstrating argyrophilia in human breast carcinomas is a complex issue, although there is general agreement that true carcinoid tumours of the breast are rare.A predominantly unselected series of breast carcinomas has been investigated for evidence of argyrophilia using the Churukian Schenk method (Churukian and Schenk 1979), alpha lactalbumin and prealbumin, a marker of neuroendocrine cells.Argyrophilia has been detected in 25% of carcinomas, including all of mucinous types. However, only 4 of the 68 tumours had a diffuse cytoplasmic reaction typical of that seen in neuroendocrine cells. The others showed a focal or subluminal/ peripheral reaction. Those argyrophilic carcinomas with demonstrable alpha lactalbumin had this latter pattern of reactivity, although the milk protein was always detected in lesser amounts by comparison. Prealbumin was only found to varying degrees in eight tumours and the majority of these had a diffuse or focal cytoplasmic argyrophilic reaction.It would appear that in only a small number of breast carcinomas, approximately six percent, does the presence of argyrophilia probably represent neuroendocrine differentiation, whilst in others it is related to the secretory nature of the tumour cells. 相似文献
70.
Riegel P Liégeois P Chenard MP Mathelin C Monteil H 《International journal of medical microbiology : IJMM》2004,294(6):413-416
The recently described species Corynebacterium kroppenstedtii was isolated from a breast abscess in a 38-year-old woman on two occasions. We discuss the pathogenic role of this bacteria and the methods used for its isolation. 相似文献