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101.
102.
Kazuhiko Sasai Rikuo Tanaka Mitsutoshi Kawamura Kazumitsu Honjo Naofumi Matsunaga Taishi Nakada Kiichi Homma Hiroshi Fujimura 《Journal of gastroenterology》1996,31(4):505-511
The requirement for well spread out chromosomes for the cytogenetic analysis of primary gastrointestinal tumors led us to
develop new techniques. These techniques involved two main procedures: (1) preliminary incubation with culture medium in the
presence of collagenase, Dispase, and colcemid, for 3h, and (2) treatment with an extremely hypotonic solution (0.044 M KCl)
for 30 min. The techniques were applied to 11 gastrointestinal malignancies (including 1 early gastric cancer and 1 metastatic
liver lesion of colon cancer) and significant increases (P<0.01) in the number of metaphases of analyzable karyotypes were obtained, compared with a previous method in which the standard
hypotonic molarity of KCL (0.075 M) was employed. The mean value for metaphase numbers of the analyzable karyotypes was 37.0±3.7%
in the 5 gastric cancers and 44.7±4.8% in the 5 colon cancers and 1 metastatic lesion. These values were three times and more
than twice, respectively, the values obtained by the previous method. A fluorescence in situ hybridization (FISH) study was
carried out on one cologenic tumor, the α-satellite centromere-specific probe 17 being used. Deletion of the long arm of chromosome
17 was demonstrated. The method proposed here could yield a sufficient number of metaphases without the use of tissue culture
that might cause alteration of karyotype. It can be employed with small biopsy specimens and in studies utilizing the FISH
technique. 相似文献
103.
Ultrastructural study of M cells from colonic lymphoid nodules obtained by colonoscopic biopsy 总被引:4,自引:0,他引:4
Dr. Yoshinori Fujimura MD Masayo Hosobe MD Tsuyoshi Kihara MD 《Digestive diseases and sciences》1992,37(7):1089-1098
The present study was undertaken to investigate ultrastructurally the epithelium covering lymphoid nodules obtained from colonoscopic biopsies of the human colon and rectum. Colonoscopy using the dye spraying contrast, method was performed in nine patients who showed x-ray evidence of lymphonodular hyperplasia. Fifty-two colonoscopical biopsy specimens, of lymphoid nodules were obtained from the ascending, transverse, and descending colon and rectosigmoid region. All specimens were observed by light and electron microscopy. Light microscopy disclosed large lymphoid follicles protruding into the lumen with a dome-type configuration. These extended to the lamina propria of the mucosa and were associated with a massive lymphoid aggregation extending as far as the muscularis mucosa from the submucosa. The epithelium covering these nodules contained a few goblet cells and many lymphocytes. Observation of the elevated surface at the apex by scanning electron microscopy revealed M cells with sparse microvilli in the dome epithelium surrounded by crypts. Transmission electron microscopy disclosed M cells enfolding many immature or mature lymphocytes and plasmocytes. The M cells had cytoplasmic microvilli (so-called microfolds) on their surfaces, well-developed tubulovesicular systems, and vacuoles in the cytoplasm. The basic structure of the M cells as observed by scanning and transmission electron microscopy was the same as that of M cells in the Peyer's patches of humans and mice. The apical surface of the colonic lymphoid follicles in Crohn's disease patients was associated with erosions observed by scanning electron microscopy. The erosions proved to be the naked surface of the dome after removal of the epithelium and many holes from 2.0 to 6.0 m in diameter were observed on the naked surface. At high magnification, lymphocytes were seen projecting from holes (18%) on the naked surface of the dome. These ultrastructural findings indicate that human colonic lymphoid follicles are very similar to those seen in other species. 相似文献
104.
Charles L Bennett Benjamin Kim Anaadriana Zakarija Nicholas Bandarenko Dilip K Pandey Charlie G Buffie June M McKoy Amul D Tevar John F Cursio Paul R Yarnold Hau C Kwaan Davide De Masi Ravindra Sarode Thomas J Raife Joseph E Kiss Dennis W Raisch Charles Davidson J Evan Sadler Thomas L Ortel X Long Zheng Seiji Kato Masanori Matsumoto Masahito Uemura Yoshihiro Fujimura 《Journal of the American College of Cardiology》2007,50(12):1138-1143
OBJECTIVES: We sought to describe clinical and laboratory findings for a large cohort of patients with thienopyridine-associated thrombotic thrombocytopenic purpura (TTP). BACKGROUND: The thienopyridine derivatives, ticlopidine and clopidogrel, are the 2 most common drugs associated with TTP in databases maintained by the U.S. Food and Drug Administration (FDA). METHODS: Clinical reports of TTP associated with clopidogrel and ticlopidine were identified from medical records, published case reports, and FDA case reports (n = 128). Duration of thienopyridine exposure, clinical and laboratory findings, and survival were recorded. ADAMTS13 activity (n = 39) and inhibitor (n = 30) were measured for a subset of individuals. RESULTS: Compared with clopidogrel-associated TTP cases (n = 35), ticlopidine-associated TTP cases (n = 93) were more likely to have received more than 2 weeks of drug (90% vs. 26%), to be severely thrombocytopenic (84% vs. 60%), and to have normal renal function (72% vs. 45%) (p < 0.01 for each). Compared with TTP patients with ADAMTS13 activity >15% (n = 13), TTP patients with severely deficient ADAMTS13 activity (n = 26) were more likely to have received ticlopidine (92.3% vs. 46.2%, p < 0.003). Among patients who developed TTP >2 weeks after thienopyridine, therapeutic plasma exchange (TPE) increased likelihood of survival (84% vs. 38%, p < 0.05). Among patients who developed TTP within 2 weeks of starting thienopyridines, survival was 77% with TPE and 78% without. CONCLUSIONS: Thrombotic thrombocytopenic purpura is a rare complication of thienopyridine treatment. This drug toxicity appears to occur by 2 different mechanistic pathways, characterized primarily by time of onset before versus after 2 weeks of thienopyridine administration. If TTP occurs after 2 weeks of ticlopidine or clopidogrel therapy, therapeutic plasma exchange must be promptly instituted to enhance likelihood of survival. 相似文献
105.
Kita T Nishi K Fujimura M Abo M Ohka T Yasui M Ogawa H Minato H Kurumaya H Nakao S 《Respirology (Carlton, Vic.)》2003,8(1):95-98
A 51-year-old housewife with hypersensitivity pneumonitis caused by Humicola fuscoatra is reported. The diagnosis was made by an inhalation challenge with H. fuscoatra antigen. She was admitted for diagnosis and treatment of a fever and productive cough. Auscultation of her lungs revealed inspiratory fine crackles. Her chest CT showed diffuse miliary nodules in a centri-lobular distribution with patchy ground glass opacities. Findings of transbronchial lung biopsy and BAL fluid were compatible with a hypersensitivity pneumonitis. Her symptoms worsened on returning home, which suggested the existence of some aetiological agent in the subject's house. H. fuscoatra, Penicillium decumbens and Aspergillus versicolor were isolated from a number of rooms. High titres of serum anti H. fuscoatra, P. decumbens and A. versicolor were detected. Inhalation challenge tests with both P. decumbens and A. versicolor antigen were negative, in contrast to that with H. fuscoatra which was positive. Based on these results, we advised the patient to cleanse her entire house. Since cleaning, her symptoms have not worsened upon returning home. This is the first report of hypersensitivity pneumonitis caused by H. fuscoatra antigen. 相似文献
106.
Hiroyuki Kimura Tomoki Nakajima Keizo Kagawa Takeshi Deguchi Masamichi Kakusui Tatsuo Katagishi Takeshi Okanoue Kei Kashima Tsukasa Ashihara 《Liver international》1998,18(1):14-19
ABSTRACT— To clarify the relationship between angiogenesis and hepatocarcinogenesis on progression of hepatocellular carcinoma (HCC), we quantitatively evaluated angiogenesis by CD34 immunohistochemistry in liver cirrhosis (LC), adenomatous hyperplasia (AH), and HCC, and proliferative activity estimated by Ki-67 immunohistochemistry. Angiogenesis was evaluated by CD34 immunohistochemistry using monoclonal antibody HPCA-2, and tumor proliferative activity was evaluated using monoclonal antibody MIB-1. We used an image analysis system to assess the microvessel density as the area percentage of the endothelial area. Angiogenesis was generally observed in HCC and there was no significant difference among all clinical stages and histological grades of HCC. On the other hand, the staining of CD34 was partly observed in sinusoids of AH, although no positive staining was seen in any sinusoids of LC. The proliferative activity was significantly correlated with the clinical stage and histological grade of HCC. Our results indicate that the quantitation of angiogenesis does not provide significant prognostic information in HCC, but that it may have diagnostic value in distinguishing HCC from non-HCC. Meanwhile, AH, which is not morphologically diagnosed as cancer, shows positive staining for CD34, suggesting that some portion of AH contains cancerous characteristics. 相似文献
107.
108.
A 50-kD integrin-associated protein (IAP) has been reported to be associated with beta 3 integrins and to modulate their function, especially vitronectin receptor in human erythroleukemia (HEL) cells and leukocyte response integrin in neutrophils. We studied the involvement of IAP in the function of platelet beta 3 integrin, glycoprotein (GP) IIb-IIIa complex. IAP was a widely distributed protein and was also expressed in the cells that do not have beta 3 integrin. Platelets from a patient with thrombasthenia, which lack GPIIb and IIIa, expressed IAP as well as normal platelets. Neither platelet aggregation nor intracellular Ca2+ elevation after stimulation was influenced by the anti-IAP antibody, B6H12, which was reported to be inhibitory for other beta 3 integrins. The expression level of GPIIb- IIIa complex was not influenced by coexpression of human IAP in the transfected Chinese hamster ovary (CHO) cells. IAP did not facilitate the binding of soluble fibrinogen to the CHO cells expressing GPIIb- IIIa complex. Furthermore, cell adhesion onto the immobilized fibrinogen via GPIIb-IIIa complex was not inhibited by B6H12 in HEL cells and was not altered by coexpression of human IAP in CHO cells. We concluded that expression of IAP is regulated independently with that of GPIIb-IIIa complex and that IAP does not influence the function of GPIIb-IIIa complex. 相似文献
109.
Is it feasible to identify preterm infants with respiratory distress syndrome for early extubation to continuous positive airway pressure post‐surfactant treatment during retrieval? 下载免费PDF全文
110.
Nobuyuki Katayama Masaki Fujimura Masahide Yasui Haruhiko Ogawa Shinji Nakao 《Allergology international》2008,57(3):277-280
We report a case of hypersensitivity pneumonitis and asthma attacks caused by environmental fungi in a 75-year-old man. The diagnosis was established by inhalation challenge with Bjerkandera adusta and Aspergillus fumigatus. The patient was admitted for treatment of fever, wheezing, and dyspnea. Chest computed tomography showed small nodular shadows with diffuse, partially patchy, ground-glass opacities. The findings of bronchoalveolar lavage fluid were compatible with hypersensitivity pneumonitis. His symptoms and objective findings, including chest radiographs, worsened after returning home, suggesting the existence of causative antigens in his house. B. adusta and A. fumigatus were isolated from the living room and bedroom. Based on the results of antigen inhalation bronchoprovocation test, he was given a diagnosis of hypersensitivity pneumonitis caused by B. adusta and bronchial asthma attacks caused by B. adusta and A. fumigatus. After cleaning the entire house, the patient has had no recurrence of the symptoms on returning home. 相似文献