全文获取类型
收费全文 | 7870篇 |
免费 | 369篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 122篇 |
儿科学 | 141篇 |
妇产科学 | 58篇 |
基础医学 | 1160篇 |
口腔科学 | 193篇 |
临床医学 | 453篇 |
内科学 | 1865篇 |
皮肤病学 | 120篇 |
神经病学 | 335篇 |
特种医学 | 321篇 |
外科学 | 1518篇 |
综合类 | 24篇 |
一般理论 | 1篇 |
预防医学 | 217篇 |
眼科学 | 113篇 |
药学 | 561篇 |
中国医学 | 24篇 |
肿瘤学 | 1059篇 |
出版年
2023年 | 35篇 |
2022年 | 77篇 |
2021年 | 136篇 |
2020年 | 71篇 |
2019年 | 99篇 |
2018年 | 126篇 |
2017年 | 109篇 |
2016年 | 115篇 |
2015年 | 128篇 |
2014年 | 162篇 |
2013年 | 201篇 |
2012年 | 353篇 |
2011年 | 362篇 |
2010年 | 218篇 |
2009年 | 194篇 |
2008年 | 354篇 |
2007年 | 390篇 |
2006年 | 371篇 |
2005年 | 385篇 |
2004年 | 367篇 |
2003年 | 384篇 |
2002年 | 407篇 |
2001年 | 264篇 |
2000年 | 239篇 |
1999年 | 227篇 |
1998年 | 110篇 |
1997年 | 102篇 |
1996年 | 64篇 |
1995年 | 75篇 |
1994年 | 65篇 |
1993年 | 72篇 |
1992年 | 193篇 |
1991年 | 190篇 |
1990年 | 165篇 |
1989年 | 163篇 |
1988年 | 161篇 |
1987年 | 169篇 |
1986年 | 134篇 |
1985年 | 128篇 |
1984年 | 78篇 |
1983年 | 55篇 |
1982年 | 33篇 |
1979年 | 61篇 |
1978年 | 37篇 |
1974年 | 32篇 |
1973年 | 36篇 |
1971年 | 41篇 |
1970年 | 33篇 |
1968年 | 41篇 |
1967年 | 35篇 |
排序方式: 共有8285条查询结果,搜索用时 15 毫秒
101.
102.
A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue. 相似文献
103.
Higashino K 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(12):1122-1128
In mail testing, a testee collects samples at home from his or her own body, and mails them to the medical institution. Because the testee does not need to attend the medical institution, an advantage of mail testing is that it is not time-consuming. Because the amount of sample is small and time from sampling to measurement is long, the manner of collecting and transporting samples are important factors affecting the precision of the result. There is the risk that inappropriate sample picking can occur, as the testee, who is not skilled in medical testing, may obtain the sample. Moreover, the samples may include blood, urine, secretions, and so on. Depending on the purpose of the test, the transport and sampling method varies, and the character of the sampling device and transport method influence the procedure required. I describe collection methods and other issues in this paper according to medical examination item, sample, and sampling. 相似文献
104.
Regulation of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and TRAIL receptor expression in human neutrophils 总被引:14,自引:0,他引:14 下载免费PDF全文
Kamohara H Matsuyama W Shimozato O Abe K Galligan C Hashimoto S Matsushima K Yoshimura T 《Immunology》2004,111(2):186-194
Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily, which is capable of inducing apoptosis in many cell types, including tumour and virus-infected cells, but rarely in normal cells. Expression of TRAIL mRNA and TRAIL receptors has previously been detected in neutrophils; however, the expression of TRAIL protein and the regulation of TRAIL and TRAIL receptor expression in these cells remain unknown. Here we report, for the first time, that neutrophils constitutively express TRAIL protein on their cell surface and that the TRAIL protein is shed during culture. TNF-alpha is a down-regulator of TRAIL expression, whereas IFN-gamma up-regulates the expression of TRAIL. Neutrophils did not express a detectable level of TRAIL-R1 or -R4, but constitutively expressed a low, but substantial, level of TRAIL-R2 and a high level of TRAIL-R3. Although the level of TRAIL-R2 was not significantly altered during culture under different experimental conditions, approximately 30% of TNF-alpha-treated cells rapidly lost their high-level TRAIL-R3 expression, whereas the majority of IFN-gamma-treated cells retained a high level of TRAIL-R3 expression. Anti-TRAIL neutralizing antibody significantly inhibited neutrophil apoptosis during cultures in medium alone, or in the presence of TNF-alpha or IFN-gamma. Thus, our study identified human neutrophils as a cellular source of TRAIL and suggests that neutrophil-derived TRAIL may play a role in immune surveillance. Our results also suggest a role for the TRAIL/TRAIL receptor system in neutrophil apoptosis. 相似文献
105.
Michio Tanaka Shutaro Satake Yutaka Kawahara Masaya Sugiura Kenzo Hirao Kazushi Tanaka Tokuhiro Kawara Akihiro Masuda Toshio Nishikawa Takeshi Kasajima 《Pathology international》1991,41(7):487-498
Radiofrequency catheter ablation of the atrioventricular (AV) node or bundle of His was performed in 12 adult mongrel dogs. The aim was to create chronic incomplete AV block (first- and second-degree AV block) and to examine the histopathology of the ablated lesions. However, the late electrophysiological results (2 4 weeks follow up) were various: normal in 2 dogs, mild PR prolongation (< 50%) in 2 dogs, first-degree AV block (PR prolongation a 50%) in 2 dogs, second degree AV block in 2 dogs, complete AV block in 4 dogs. The maximally ablated area (%) of the atrioventricular conduction system in serial histologic sections from dogs with these conditions was 69%, 75%, 89.5%, 95% and 99.5%, respectively. The number of intact conduction cells at the maximally ablated site varied from 6 to 30 in the four cases of incomplete AV block. The mean ablated volume (%) of either the AV node or penetrating His bundle correlated roughly with the degree of AV block. The ablated lesions were well demarcated and almost replaced by dense fibrous tissue at 4 weeks. Interruption (3 dogs) or thinning (1 dog) of the endocardial elastic lamellae was detected, in association with endocardial thickening (mean 913 μm). Endocardial thrombi were found in 3 dogs (2 fresh, 1 organized). We conclude that radiofrequency catheter ablation does not cause severe complicated lesions. Several possible conditions for creating chronic incomplete AV block are discussed. Acta Pathol Jpn 41: 487–498, 1991. 相似文献
106.
Connexin 26 distribution in gap junctions between melanocytes in the human vestibular dark cell area
Masuda M Usami S Yamazaki K Takumi Y Shinkawa H Kurashima K Kunihiro T Kanzaki J 《The Anatomical record》2001,262(2):137-146
We have previously demonstrated the presence of gap junctions between melanocytes in the human vestibular organ and have speculated that melanocytes function in maintaining the homeostasis of the microenvironment of the inner ear. The purpose of the present study was to characterize the expression and ultrastructural localization of connexin (Cx) protein in melanocytes of the human vestibular organs. Surgical material was obtained from patients operated on for vestibular schwannoma and was processed for light microscopy, confocal laser scanning microscopy, conventional TEM, and immuno TEM. The specimens were labeled with anti-Cx26, Cx32, and Cx43 antibodies and examined by light microscopy. Specimens were also labeled with anti-Cx26 antibody and examined by laser microscopy and immuno-TEM methods. The specimens examined in this study were mainly dark cell areas from the human vestibular organ, whose epithelial and subepithelial layers are rich in melanocytes. Light-microscopic immunohistochemical studies showed positive labeling for Cx26 protein between subepithelial melanocytes, and Cx32 was also detected. Use of anti-Cx26 antibody and confocal laser scanning microscopy revealed high levels of Cx26 around the subepithelial melanocytes. Post-embedding immuno-gold transmission electron microscopy showed significant aggregation of gold particles (33.97 +/- 8.01% of total gold particles) around the gap junctions of the subepithelial melanocytes. The results of this study indicated that melanocytes are connected through gap junctions that mainly contain Cx26. This suggested that the melanocytes in the human vestibular organ may play a role in transporting material between the endolymph and perilymph. 相似文献
107.
Phylogenetic analyses of Chlamydia psittaci strains from birds based on 16S rRNA gene sequence. 下载免费PDF全文
T Takahashi M Masuda T Tsuruno Y Mori I Takashima T Hiramune N Kikuchi 《Journal of clinical microbiology》1997,35(11):2908-2914
The nucleotide sequences of 16S ribosomal DNA (rDNA) were determined for 39 strains of Chlamydia psittaci (34 from birds and 5 from mammals) and for 4 Chlamydia pecorum strains. The sequences were compared phylogenetically with the gene sequences of nine Chlamydia strains (covering four species of the genus) retrieved from nucleotide databases. In the neighbor-joining tree, C. psittaci strains were more closely related to each other than to the other Chlamydia species, although a feline pneumonitis strain was distinct (983 to 98.6% similarity to other strains) and appeared to form the deepest subline within the species of C. psittaci (bootstrap value, 99%). The other strains of C. psittaci exhibiting similarity values of more than 99% were branched into several subgroups. Two pigeon strains and one turkey strain formed a distinct clade recovered in 97% of the bootstrapped trees. The other pigeon strains seemed to be distinct from the strains from psittacine birds, with 88% of bootstrap value. In the cluster of psittacine strains, three parakeet strains and an ovine abortion strain exhibited a specific association (level of sequence similarity, 99.9% or more; bootstrap value, 95%). These suggest that at least four groups of strains exist within the species C. psittaci. The 16S rDNA sequence is a valuable phylogenetic marker for the taxonomy of chlamydiae, and its analysis is a reliable tool for identification of the organisms. 相似文献
108.
BACKGROUND: It has been reported that local thermal therapy with a hot pack or paraffin relieves pain. We hypothesized that systemic warming may decrease pain and improve the outcomes in patients with chronic pain. The purpose of this study was to clarify the effects of systemic thermal therapy in patients with chronic pain. METHODS: Group A (n = 24) patients with chronic pain were treated by a multidisciplinary treatment including cognitive behavioral therapy, rehabilitation, and exercise therapy, whereas group B (n = 22) patients were treated by a combination of multidisciplinary treatment and repeated thermal therapy. A far-infrared ray dry sauna therapy and post-sauna warming were performed once a day for 4 weeks during hospitalization. We investigated the improvements in subjective symptoms, the number of pain behavior after treatment and outcomes 2 years after discharge. RESULTS: The visual analog pain score, number of pain behavior, self-rating depression scale, and anger score significantly decreased after treatment in both groups. After treatment, the number of pain behavior was slightly smaller (p = 0.07) and anger score was significantly lower in group B than those in group A (p = 0.05). Two years after treatment, 17 patients (77%) in group B returned to work compared with 12 patients (50%) in group A (p < 0.05). CONCLUSION: These results suggest that a combination of multidisciplinary treatment and repeated thermal therapy may be a promising method for treatment of chronic pain. 相似文献
109.
110.
Y H Park T Suzuki M Miyama-Inaba T Masuda Y Yoshida H Uchino 《International archives of allergy and applied immunology》1986,81(2):156-164
Cloned TS4.44 cells, which were hybridized HAT-sensitive 3T3-4E cells with B cells stimulated by immune complexes produce a lymphokine, biochemical and biological characteristics of which are identical with those of conventional suppressive B cell factor (SBF) synthesized by Fc receptor bearing B cells stimulated with immune complexes. This factor is known to suppress B cell responses to antigen/mitogen. The present studies were carried out by using this hybridoma-derived SBF to characterize the large proportion of B cells sensitive to SBF and the small proportion of B cells resistant to it in terms of affinities of antibodies which these cells are able to produce. The treatment of normal spleen cells with SBF resulted in a 50-70% decrease in anti-dinitrophenyl (DNP) antibody production when the cells were transferred into X-ray-irradiated mice along with alum-precipitated dinitrophenyl-conjugated keyhole limpet hemocyanin (DNP-KLH). The affinity of anti-DNP antibody molecules produced in these mice was significantly lower than that of the controls, even if immunization was repeated. The target cells for SBF were B, and not helper T cells which might be involved in the process of affinity maturation. A single treatment of spleen cells in vitro with SBF was sufficient to abrogate the precursors committed to mediate high-affinity anti-DNP antibody responses, since the retreatment with SBF in vitro and transfer into the second irradiated recipients along with antigens of spleen cells of mice to which SBF-treated spleen cells were transferred 3 weeks before resulted in almost the same level of plaque-forming-cell-responses as in mice which received medium-treated.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献