全文获取类型
收费全文 | 3761篇 |
免费 | 187篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 84篇 |
妇产科学 | 34篇 |
基础医学 | 900篇 |
口腔科学 | 49篇 |
临床医学 | 177篇 |
内科学 | 759篇 |
皮肤病学 | 144篇 |
神经病学 | 358篇 |
特种医学 | 108篇 |
外科学 | 521篇 |
综合类 | 10篇 |
预防医学 | 68篇 |
眼科学 | 127篇 |
药学 | 214篇 |
中国医学 | 7篇 |
肿瘤学 | 405篇 |
出版年
2023年 | 23篇 |
2022年 | 26篇 |
2021年 | 66篇 |
2020年 | 40篇 |
2019年 | 72篇 |
2018年 | 67篇 |
2017年 | 54篇 |
2016年 | 60篇 |
2015年 | 67篇 |
2014年 | 96篇 |
2013年 | 121篇 |
2012年 | 165篇 |
2011年 | 188篇 |
2010年 | 96篇 |
2009年 | 96篇 |
2008年 | 224篇 |
2007年 | 207篇 |
2006年 | 230篇 |
2005年 | 291篇 |
2004年 | 281篇 |
2003年 | 290篇 |
2002年 | 274篇 |
2001年 | 48篇 |
2000年 | 29篇 |
1999年 | 61篇 |
1998年 | 76篇 |
1997年 | 81篇 |
1996年 | 50篇 |
1995年 | 61篇 |
1994年 | 50篇 |
1993年 | 54篇 |
1992年 | 43篇 |
1991年 | 26篇 |
1990年 | 27篇 |
1989年 | 37篇 |
1988年 | 21篇 |
1987年 | 19篇 |
1986年 | 31篇 |
1985年 | 20篇 |
1984年 | 25篇 |
1983年 | 22篇 |
1982年 | 8篇 |
1981年 | 12篇 |
1980年 | 23篇 |
1979年 | 6篇 |
1978年 | 16篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1975年 | 7篇 |
1969年 | 7篇 |
排序方式: 共有3979条查询结果,搜索用时 15 毫秒
21.
Masaru Kojima Shigeo Nakamura Yasuo Hosomura Kazuhiko Shimizu Yoshiyuki Kurabayashi Hideaki Itoh Katsue Yoshida Yoshihiro Ohno Akihiro Kaneko Shigeyuki Asano Haruki Wakasa Taizan Suchi Takashi Johshita 《Pathology international》1993,43(1-2):11-17
In order to clarify the histological and immunohistochemical characteristics of suppurative granuloma in abscess-forming granulomatous lymphadenitis (AGL), and the relation between AGL and cat scratch disease (CSD), 36 cases of AGL were studied. The combined results showed that there were two types of suppurative granulomas. The suppurative granulomas histologically revealed small lymphocytes of predominantly T cell phenotype distributed among the epithelioid histiocytes bordering central necrotic areas in the suppurative granulomas. These suppurative granulomas could be further subdivided into two groups, mainly those with and without the intermingling of large transformed cells of B-cell phenotypes: Type B granuloma with large transformed B cells and Type A without large transformed B cells. Both types of granulomas were observed in a varying degree in most cases. According to the predominant type of granulomas, 36 patients with AGL were further classified into two groups: Group I of Type A dominance and Group II of Type B dominance. Warthin-Starry (WS) silver stain positive bacteria, which are said to be a causative agent of CSD, were present in about 50% of both groups. No Brown-Hopps' Gram-positive bacteria, fungus, toxoplasma, Chlamydia or Bacillus Calmette-Guerin antigen were found in any case. Clinically, there was no significant difference between these two groups. On the other hand, the detection of WS-positive bacteria seemed to have some relationship with the duration of disease and the history of exposure to cats, and 70% of AGL cases occurred in autumn without a single concurrent epidemic. 相似文献
22.
Balamuthia mandrillaris is a free-living ameba that causes granulomatous amebic encephalitis in both immunocompromised and immunocompetent individuals. Because of a lack of pathognomonic symptoms and the difficulty in recognizing amebas in biopsied tissues, most cases are not diagnosed or effectively treated, leading to a >95% mortality. We report here on five cases of balamuthiasis that were diagnosed by indirect immunofluorescence (IIF) staining of serum for anti-Balamuthia antibodies (titer > or = 1:128) and confirmed by IIF of unstained brain tissue sections and/or detection of amebas in hematoxylin-eosin-stained slides. Additionally, we have used the PCR for the detection of mitochondrial 16S rRNA gene DNA from the ameba in clinical specimens such as brain tissue and cerebrospinal fluid (CSF) from individuals with Balamuthia encephalitis. Balamuthia DNA was successfully detected by the PCR in clinical samples from all five individuals. It was detected in brain tissue from three cases, in CSF from three cases, and in one of two samples of lung tissue from two individuals, but not in two samples of kidney tissue tested. One sample of unfixed brain tissue was culture positive for Balamuthia. In order to test the sensitivity of the PCR for detection of Balamuthia DNA, CSF specimens from two individuals negative for amebic infection were spiked with Balamuthia amebas. We found that it was possible to detect Balamuthia DNA in the PCR mixtures containing mitochondrial DNA from 1 to as little as 0.2 ameba per reaction mixture. A single Balamuthia ameba contains multiple mitochondrial targets; thus, 0.2 ameba represents multiple targets for amplification and is not equivalent to 0.2 of an ameba as a target. 相似文献
23.
Kojima M Nakamura S Shimizu K Yamane Y Itoh H Masawa N 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(12):1133-1136
A completely infarcted lymph node is an unusual event. However, lymph node infarction should alert the pathologist to the considerable likelihood of malignant lymphoma. We report two unusual cases of acute myeloid leukemia presenting with granulocytic sarcoma at disease onset with a lymph node lesion exhibiting extensive lymph node infarction. The infarcted tissue contained numerous eosinophilic cell ghosts. There were some islands of degenerated, pyknotic medium-sized nuclei resembling lymphoblasts present in the necrotic area. By immunohistochemistry, these medium sized cells were CD3-, CD20-, CD34+, CD43+, CD45RO-, CD68-, CD79a- and myeloperoxidase+ in both cases. Differentiation of granulocytic sarcoma from malignant lymphomas is important for adequate therapy. The present cases indicate that granulocytic sarcoma should be added to the list of differential diagnoses for lymph node infarction. 相似文献
24.
25.
Shigeru Furuhata Toru Kameya Tomoko Tsuruta Heiji Naritaka Mitsuhiro Otani Shigeo Toya 《Endocrine pathology》1992,3(4):201-204
A 51 -year-old woman with mixed growth hormone (GH) cell-prolactin (PRL) cell pituitary adenoma is presented. She had clinical
signs due to hypersecretion of GH and PRL. Resected tissue was studied immunohistochemically and morphologically. The serial
sections revealed that GH and α-subunit were co-localized in most cells, while GH and PRL were localized in different cells. 相似文献
26.
Hiroto Yamashita Shiro Noguchi Iwao Nakayama Hiroshi Togon Akira Moriuchi Shigeo Yokoyama Yuichi Mochizuki Akito Noguchi 《Pathology international》1984,34(1):123-132
A case of nonfunctioning parathyroid carcinoma in a 69-year-old female has been studied by light and electron microscopy. The tumor, located on the left side of the anterior neck, was well encapsulated by connective tissue but showed invasion to the capsule and to the thyroid. The tumor cells exhibited a trabecular arrangement surrounded by capillary networks but focally showed several ductal structures. They were polygonal in shape, had a large nucleus showing frequent mitosis and poor cytoplasm containing glycogen. Some tumor cells had clear and abundant cytoplasm, and resembled water-clear cells of the parathyroid. Immunohistochemically, no thyroglobulin was demonstrated in the tumor tissue. Electronmicroscopically, the tumor cells with high N/C ratio contained poorly developed cell organelles and abundant glycogen particles. They were poor in secretory granules and had no conglomeration of lipid. Desmosomes and tonoflbrils were observed. The ratio of the reported number of nonfunctioning parathyroid carcinoma to that of functioning one in Japan was compared with that in western countries. No difference of the ratio was found between these two, when identical criteria were employed. 相似文献
27.
Kojima M Nakamura S Ban S Inagaki M Sugihara S Yoshida K Masawa N 《Pathology, research and practice》2002,198(10):685-688
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT. 相似文献
28.
Masahiro Yasuda Shogo Tanaka Hiroshi Arakawa Yasuho Taura Yuichi Yokomizo Shigeo Ekino 《Anatomical record (Hoboken, N.J. : 2007)》2002,266(4):207-217
The calf contains two types of Peyer's patches (PPs): jejunal and ileal. The ileal PP has been thought to be equivalent to the bursa of Fabricius (BF) as a central lymphoid organ. The morphologies of ileal and jejunal PPs in the calf were compared with those of the BF and the caecal tonsil (CT) in the chicken. Immunoglobulin G–positive (IgG+) cells appear in the follicles of them all and exhibited a dendritic appearance after birth. We investigated whether the IgG in these follicles was produced in situ. IgG‐producing cells were detected in the follicular medullas of the jejunal PP and the CT, but not in those of the ileal PP and the BF. CD4+ cells were distributed in the follicular medullas of the jejunal PP and the CT, but not in those of the ileal PP and the BF. The data suggest that Ig class switching occurs in both jejunal PP follicles and CT follicles, but does not occur in either the ileal PP follicles or the bursal follicles. Because CD4+ T cells would be prerequisite for Ig class switching in these follicles, IgG+ cells of the follicular medullas in the ileal PP and the BF would trap immune complexes from the gut lumen. The primary B‐cell repertoire might be selected by gut‐derived antigens in the ileal PP and the BF before seeding the periphery. Anat Rec 266:207–217, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
29.
Yasuo Saegusa Yasuhiro Ozeki Shigeo Harada Shigeo Nakamura 《Macromolecular chemistry and physics.》1994,195(9):3189-3198
A novel thermally stable and semiconducting polyheterocycle, poly(1,3,4-thiadiazole amine), was synthesized from 2-(p-aminophenyl)-1,3,4-oxadiazoline-5-thione via ring-opening. The polymer is a new class of ordered alternating copoly(aniline) containing 1,3,4-thiadiazole heterocyclic units. An investigation of the reaction of 2-phenyl-1,3,4-oxadiazoline-5-thione with aniline was conducted as a model reaction for the polymerization, and poly(phosphoric acid) (PPA) and phosphorus pentoxide/methanesulfonic acid (PPMA) were found to be favorable both as condensing agent and solvent for the formation of 2-anilino-5-phenyl-1,3,4-thiadiazole as a model compound. The polymerization was carried out both by two-step procedure that included ring-opening self-polyaddition giving poly(1-benzoylthiosemicarbazide), followed by cyclodehydration to poly(1,3,4-thiadiazole amine), and by a one-step procedure including cyclodehydration in situ. The poly(1-benzoylthiosemicarbazide) which was formed in the first step in m-cresol had reduced viscosities up to 0,42 dL·g?1, and it was converted to poly(1,3,4-thiadiazole amine) by treating in PPA or PPMA. Poly(1,3,4-thiadiazole amine) having reduced viscosities up to 0,25 dL·g?1 was also synthesized by the direct one-step polymerization in PPA or PPMA. The polymer is highly thermally stable and exhibited no weight loss up to 350°C under nitrogen. Its electric conductivity was less than 10?10 S·cm?1 at ambient temperature, but markedly increased to 2,9·10?7 S·cm?1 upon doping with iodine. 相似文献
30.
Takashi Sekine Keiko Fukutani Tomiko Motegi Hiroshi Hayakawa Takashi Tamura Shigeo Nagafuchi Yutaka Nakahori Yasuo Nakagome 《Journal of human genetics》1992,37(2):157-162
Summary Results of DNA study on two patients of gonadal dysgenesis with a 45,X/46,X,Ynf (non-fluorescent Y chromosome) karyotype are described. In one patient who developed gonadoblastoma, all 12 loci on the non-fluorescent part of Yq were detected. Another patient did not have gonadoblastoma at 20 years, and only the proximal 6 loci out of 12 were detected. 相似文献