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61.
The levels of superoxide dismutase (SOD), a highly specific scavenging enzyme for superoxide anion radicals (O2-), and lipid peroxide produced by oxygen free radicals were measured in human seminal plasma and spermatozoa. Seminal plasma contained 366.8 +/- 20.9 U/ml (mean +/- SE) of SOD activity. SOD activity in human spermatozoa showed a significant correlation to the number of motile spermatozoa, while the activity in seminal plasma did not relate to the sperm concentration or motility. The lipid peroxide concentration in seminal plasma was 6.22 +/- 0.46 nmol/ml and had no significant relationship to sperm concentration or motility. The malondialdehyde (MDA) concentration in spermatozoa was significantly related to the number of immotile spermatozoa. A decrease in the motility of spermatozoa incubated in medium without seminal plasma was observed after 120 min, while the MDA concentration of the spermatozoa increased. Addition of exogenous SOD (400 U/ml) to the sperm suspension significantly decreased this loss of motility and the increase of the MDA concentration. These data suggest a significant role for SOD in sperm motility. It seems that lipid peroxidation of human spermatozoa may cause loss of motility and that SOD may inhibit this lipid peroxidation. These results suggest that SOD may have a possible clinical application in the use of spermatozoa for in-vitro fertilization (IVF) or artificial insemination. 相似文献
62.
Depression of the generation of cell-mediated cytotoxicity by suppressor cells after surgery 下载免费PDF全文
S Miyazaki T Akiyoshi S Arinaga F Koba T Wada H Tsuji 《Clinical and experimental immunology》1983,54(2):573-579
The effects of surgical operation on the generation of cell-mediated cytotoxicity in mixed cell cultures were studied in patients with various carcinomas or benign lesions. Peripheral blood mononuclear cells from patients were cultured with B lymphoblastoid cell line Raji in mixed culture, and the induced cytotoxicity was measured by 51Cr release assay. In 15 patients with various carcinomas, the capacity of cells to generate cytotoxic cells was significantly depressed 1, 3 and 6 days after surgery, as compared to that before surgery. It returned to the pre-operative level by the 8th post-operative day. In eight patients with benign lesions, significant decrease in cytotoxic cell activity was observed 3 and 6 days after operation. At the 8th day, however, there was a significant increase in the generated cytotoxicity. The depressed generation of cytotoxic cells 3 days after surgery could be abrogated by removal of adherent cells from the responding cell population. This effect could be partially reconstituted by addition of separated, autologous adherent cells back to the responding non-adherent cell culture. These results demonstrate that suppressor cells, presumably monocytes, may be responsible for the depressed generation of cytotoxic cells after surgery. 相似文献
63.
Shiraki M Aihara H Kinouchi Y Takahashi S Oki M Noguchi M Takahashi K Miyazaki J Shimosegawa T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(11):1491-1500
T-helper-1 (Th1) cytokines play an important role in Crohn's disease, and interleukin-12 (IL-12), which is composed of two subunits, p40 and p35, drives Th1 differentiation. In previous reports, IL-12 p40 was shown to prevent IL-12 from binding to the receptor. We demonstrate here the effect of IL-12 p40 overexpression in intestinal epithelia on enterocolitis mediated by Th1 cells in IL-10-deficient (IL-10(-/-)) mice on a C57BL/6J background. IL-10 deficient (IL-10(-/-))/T3b-IL-12 p40+ (IL-12 p40+) mice and IL-10(-/-)/T3b-IL-12 p40- (IL-12 p40-) mice were generated by crossing T3b-IL-12 p40 transgenic mice and IL-10(-/-) mice. At 8 weeks of age, IL-12 p40+ mice did not show any clinical manifestations of colitis. The colon length of IL-12 p40- mice became shorter than that of IL-12 p40+ mice. The histological score of IL-12 p40+ mice was lower. Interferon-gamma (IFN-gamma) production was suppressed in both the mesenteric lymph node cell culture and colon tissue culture of IL-12 p40+ mice. There was no significant difference in IL-4 production and tumor necrosis factor-alpha (TNF-alpha) production between the two groups. These results show that overexpression of IL-12 p40 in intestinal epithelia prevents enterocolitis in IL-10(-/-) mice by suppressing IFN-gamma production, and suggest a potential clinical application of IL-12 p40 for Crohn's disease. Furthermore, these results also suggest that local gene transduction in the intestinal epithelium may be a potent therapeutic approach for Crohn's disease. 相似文献
64.
Hamada K Sasaki T Koni PA Natsui M Kishimoto H Sasaki J Yajima N Horie Y Hasegawa G Naito M Miyazaki J Suda T Itoh H Nakao K Mak TW Nakano T Suzuki A 《Genes & development》2005,19(17):2054-2065
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis. 相似文献
65.
Y Nakao H Matsumoto T Miyazaki H Nishitani K Takatsuki R Kasukawa S Nakayama S Izumi T Fujita K Tsuji 《Clinical and experimental immunology》1980,42(1):20-26
Serum samples from 100 patients with myasthenia gravis, 322 with Graves' disease, 113 with Hashimoto's disease, 132 with systemic lupus erythematosus (SLE), 192 with insulin-dependent juvenile diabetes mellitus, 83 with Behçet's syndrome, 73 with psoriasis vulgaris, 258 with leprosy, 112 with Duchenne progressive muscular dystrophy and 343 non-related normal controls were studied for Gm allotypes. The incidence of Gm phenotypes with Gm(2) was significantly increased in patients with myasthenia gravis. Graves' disease, Hashimoto's disease, and high in SLE patients. The Gm1,2,21 haplotype was increased in patients with myasthenia gravis (chi 2 = 34 . 08, corrected P less than 0 . 001), Hashimoto's disease (chi 2 = 12 . 39, corrected P less than 0 . 05), Graves' disease (chi 2 = 8 . 65, corrected P less than 0 . 05), and SLE (chi 2 = 6 . 41, 0 . 1 greater than corrected P greater than 0 . 05). The total chi-square for the four different Gm haplotypes was significantly increased in patients with myasthenia gravis (chi 2 = 44 . 46, corrected P less than 0 . 001), SLE (chi 2 = 20 . 70, corrected P less than 0 . 005), Hashimoto's disease (chi 2 = 17 . 03, corrected P less than 0 . 025), and Graves' disease (chi 2 = 11 . 87, corrected P less than 0 . 025). Our data suggest the presence of Gm-associated pathogenic polygenes in certain autoimmune disorders. 相似文献
66.
WSX-1 is required for resistance to Trypanosoma cruzi infection by regulation of proinflammatory cytokine production 总被引:6,自引:0,他引:6
Hamano S Himeno K Miyazaki Y Ishii K Yamanaka A Takeda A Zhang M Hisaeda H Mak TW Yoshimura A Yoshida H 《Immunity》2003,19(5):657-667
WSX-1 is a class I cytokine receptor with homology to the IL-12 receptors and is essential for resistance to Leishmania major infection. In the present study, we demonstrated that WSX-1 was also required for resistance to Trypanosoma cruzi. WSX-1-/- mice exhibited prolonged parasitemia, severe liver injury, and increased mortality over wild-type mice. WSX-1-/- splenocytes produced enhanced levels of Th2 cytokines, which were responsible for the prolonged parasitemia. Massive necroinflammatory lesions were observed in the liver of infected WSX-1-/- mice, and IFN-gamma that was overproduced in WSX-1-/- mice compared with wild-type mice was responsible for the lesions. In addition, vast amounts of various proinflammatory cytokines, including IL-6 and TNF-alpha, were produced by liver mononuclear cells in WSX-1-/- mice. Thus, during T. cruzi infection, WSX-1 suppresses liver injury by regulating production of proinflammatory cytokines, while controlling parasitemia by suppression of Th2 responses, demonstrating its novel role as an inhibitory regulator of cytokine production. 相似文献
67.
Ping Xu Shuichi Hashimoto Hiroyuki Miyazaki Koushi Asabe Sachiko Shiraishi K. Sueishi 《Virchows Archiv : an international journal of pathology》1998,432(1):17-25
Morphometric analyses of the immunohistochemical expression of the Clara cell secretory 10-kDa protein (CC10) and surfactant
apoproteins A and B (SP-A and -B) were carried out on the developing bronchi and bronchioles of human fetuses and neonates.
We analysed the ratio of the number of CC10-positive cells per subepithelial length of the bronchial or bronchiolar basement
membrane and found that both the bronchial and the bronchiolar population of CC10-positive cells was significantly higher
than that of either SP-A or SP-B. In addition, CC10 was found to be distributed mainly in the bronchiole. CC10-positive cells
began to be recognized in the late pseudoglandular phase (15 weeks of gestation) and thereafter gradually increased in the
canalicular and terminal sac phases, which correspond to the active development period of the acini or peripheral airways.
The earliest expression of SP-A was also noted at 15 weeks of gestation, but its positive epithelial cells were present mainly
in the larger bronchi. Double immunohistochemical staining for CC10 and SP-A revealed that the CC10-positive cells lining
both the bronchi and bronchioles were different from the SP-A-positive cells. This finding suggests that CC10-positive cells
are functionally and developmentally heterogeneous in both fetal and neonatal lungs in humans
Received: 22 May 1997 / Accepted: 21 July 1997 相似文献
68.
Jin Y Kuroda N Kakiuchi S Yamasaki Y Miyazaki E Hayashi Y Toi M Naruse K Hiroi M Enzan H 《Pathology international》2000,50(5):421-426
The case of a 52-year-old Japanese man with bronchial granular cell tumors with osteopontin and osteonectin expression is reported here because there have been few investigations of their expression in benign tumors. He was admitted because of sudden hematemesis. A bronchoscopic examination revealed a lobulated polypoid tumor located in the left and right bronchi. Histologically, most tumor cells had abundant granular eosinophilic cytoplasm and were immunoreactive for S-100, neuron-specific enolase (NSE), CD68 and vimentin. Moreover, osteopontin-positive tumor cells were randomly distributed in the tumor tissue, but few stromal cells were positive. In contrast, osteonectin was mainly expressed in the peripheral tumor cells and was also distributed in the stromal cells. Blood vessels at the tumor border in which osteonectin-positive tumor cells were distributed, proliferated moderately. These results suggest that osteopontin and osteonectin may play a role in the progression of granular cell tumors and in the interaction between the tumor and host or angiogenesis around the tumor, respectively. 相似文献
69.
Adhesion molecule expression in Graves'' thyroid glands; potential relevance of granule membrane protein (GMP-140) and intercellular adhesion molecule-1 (ICAM-1) in the homing and antigen presentation processes. 下载免费PDF全文
To assess the potential role of adhesion molecules in the pathogenesis of Graves' disease, we examined the expression of several of these adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule (VCAM-1) and granule membrane protein-140 (GMP-140), in sections of Graves' thyroid glands and control thyroids, using immunohistochemical techniques. Up-regulated expression of GMP-140 was frequently observed on endothelial cells (EC) of post-capilliary venules in all Graves' thyroids examined, compared with an occasional weak staining on EC control glands. Some capillary EC around thyroid follicles (perifollicular EC) were strongly positive for GMP-140 in the Graves' thyroids in contrast to a negative staining on the same structures in the control glands. In addition, there was a correlation between the reactivity and frequency of GMP-140 expression on EC and the severity of mononuclear cell (MNC) infiltration in the Graves' thyroids. The expression of ICAM-1 was up-regulated on perifollicular EC and EC of small venules in some thyroids of both Graves' and control groups. Conversely, no significant expression was observed on any type of EC for both endothelial-leucocyte adhesion molecule-1 (ELAM-1) and VCAM-1. However, dendritic-like cells, present within lymphocytic infiltrates, were positive for VCAM-1 in most of the Graves' thyroids examined, especially in those with a severe lymphocytic infiltration. Thyrocytes were constantly negative for the expression of all four adhesion molecules investigated. These data suggest that GMP-140, as well as ICAM-1, could play an important role in the initiation of MNC infiltration in Graves' disease. ELAM-1 and VCAM-1 appear not to be relevant for the migration of MNC from the blood vessels into the target gland, although VCAM-1 expression on dendritic-like cells might play an additively tissue-selective role in autoantigen presentation and subsequent elicitation of autoimmune phenomena. 相似文献
70.
Emiko Ono Yuji Maeda Hidenori Tanimoto Yuma Fukutomi Chiyako Oshikata Kiyoshi Sekiya Takahiro Tuburai Naomi Turikisawa Mamoru Otomo Masami Taniguchi Houta Ishii Akihiko Asahina Eishi Miyazaki Tosihide Kumamoto Kazuo Akiyama 《Arerugī》2007,56(6):587-592
BACKGROUND: Recently, it is recognized that the patients of oral allergy syndrome (OAS) to fruits are increasing. However, there are little knowledges of the background, character, and seriousness about these patients in Kanto regions. OBJECTIVE: We aimed to investigate the clinical features of OAS patients to plant origin foods in Kanto regions. METHODS: The patient, who visited Sagamihara National Hospital from 2000 to 2005 and developed some allergic symptoms to plant origin foods, were studied by a questionary survey. RESULTS: As for the 42 subjects, average age are 36 years old, male:female=8:34, merger of other allergic disease is 35 allergic rhinitis of 42 subjects (83%), 34 of asthma (81%), 14 of atopic dermatitis (33%). The causes of OAS symptoms are 32 rose-family fruits, 34 non-rose family fruits, 14 vegetables, 11 nuts, 2 grains subjects. As for the symptom, only in the oral and pharynx symptoms are found in 12, the systemic symptoms is 29, anaphylaxis is 11 subjects. Allergic rhinitis preceded on the 90% subjects with pollinosis, very high rate. On the other hand, the 20% of all subjects have no symptoms of allergic rhinitis. CONCLUSION: A nasal catarrh symptoms went ahead in most of the OAS subjects in Kanto regions. In addition, considering from some patients have no black alder pollinosis and/or are allergic to many non-rose-family fruits at high frequency, there might be a broad cross-reactivity between many pollens other than alder and plant origin foods. 相似文献