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161.
H Iwata C Arai Y Koike Y Hirouchi K Kobayashi Y Nomura M Enomoto 《Toxicologic pathology》1990,18(3):373-379
Out of the 365 young laboratory beagle dogs which were used in 17 toxicity bioassays, 15 cases (4.1%) were diagnosed as having congenital heterotopic gastric mucosa of the small intestine. Its incidence in the male dogs (12 cases out of 187) was higher than in the female dogs (3 cases out of 178). Grossly, the lesions were seen as an ulcerous focus of the small intestine, 25 cm to 88 cm proximal to the ileocecal valve. All of the lesions were quite similar histologically and electron microscopically to the normal gastric mucosa, which are composed of the surface mucous cells, chief cells, parietal cells, mucous neck cells and basal granulated cells of the stomach. And consequently, they were considered to be that of a congenital heterotopic tissue in the small intestine. The only morphological characteristic of these lesions different from the regular gastric mucosa was an association with the tubular structure seen in the basal region of these mucosal layers. These cells were considered to be of mucous-secreting cell origin because of secreting type III mucous evident from paradoxical concanavalin A or periodic acid Schiff stains. They seemed to be protecting the surrounding intestinal mucosa from gastric acid. 相似文献
162.
163.
Characterization and expression of cDNA encoding coproporphyrinogen oxidase from a patient with hereditary coproporphyria 总被引:2,自引:1,他引:2
Fujita Hiroyoshi; Kondo Masao; Taketani Shigeru; Nomura Nakao; Furuyama Kazumichi; Akagi Relko; Nagai Tadashi; Terajima Masanori; Galbraith Richard A.; Sassa Shigeru 《Human molecular genetics》1994,3(10):1807-1810
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was 相似文献
164.
165.
166.
IgG inhibits the increase of platelet-associated C3 stimulated by anti-platelet antibodies 总被引:1,自引:0,他引:1 下载免费PDF全文
S. Nomura Y. Miyazaki T. Miyake K. Yamaguchi H. Kido T. Kawakatsu T. Fukuroi H. Kagawa M. Suzuki M. Yanabu T. Kokawa 《Clinical and experimental immunology》1993,93(3):452-455
We investigated the increase of platelet-associated IgG and complement component 3 (C3) caused by the in vitro action of anti-platelet MoAbs, and the effect of mouse and human IgG on these events. Anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib MoAbs caused a slight increase of C3, but not of platelet-associated IgG. In contrast, anti-CD9 and anti-Fcγ II receptor MoAbs caused an increase of both platelet-associated C3 and IgG. In particular, three MoAbs which activated the complement system caused a marked increase of C3. When platelet-rich plasma was treated with aspirin and prostaglandin E1 before incubation with antibodies, the increase of platelet-associated IgG was inhibited in all cases. In contrast, the increase of platelet-associated C3 was scarcely influenced. These results suggest that the binding to platelets of platelet-activating antibodies caused the increase expression of IgG molecules on the platelet surface and a possible increase of platelet-associated IgG. However, the increase of platelet-associated C3 appeared to depend on specific characteristics of the antibodies tested, such as a complement-activating effect. In addition, intact mouse or human IgG inhibited the increase of platelet-associated C3 caused by complement-activating antibodies, while F(ab')2 mouse or human IgG had no such effect. This suggested that the Fc portion of IgG may block the increase of C3 mediated by anti-platelet antibodies. 相似文献
167.
In Cambodia, nearly half of pregnant women attend antenatal care (ANC), which is an entry point of services for prevention
of mother-to-child transmission of HIV (PMTCT). However, most of ANC services are provided in health centres or fields, where
laboratory services by technicians are not available. In this study, those voluntary confidential counselling and testing
(VCCT) counsellors involved in PMTCT were trained by experienced laboratory technicians in our centre on HIV testing using
Determine (Abbot Laboratories) HIV1/2 test kits through a half-day training course, which consisted of use of a pipette, how
to process whole blood samples, and how to read test result. The trained counsellors were midwives working for ANC and delivery
ward in our centre without any experience on laboratory works. The objective of this study was to assess the feasibility of
the training by evaluating the proficiency of the trained non-laboratory staffs. The trained counsellors withdrew blood sample
after pre-test counselling following ANC, and performed the rapid test. Laboratory technicians routinely did the same test
and returned reports of the test results to counsellors. Reports by the counsellors and the laboratory technicians were compared,
and discordant reports in two groups were re-tested with the same rapid test kit using the same blood sample. Cause of discordance
was detected in discussion with both groups. Of 563 blood samples tested by six trained VCCT counsellors and three laboratory
technicians, 11 samples (2.0%) were reported positive in each group, however four discordant reports (0.7%) between the groups
were observed, in which two positive reports and two negative reports by the counsellors were negative and positive by the
laboratory technicians, respectively. Further investigation confirmed that all the reports by the counsellors were correct,
and that human error in writing reports in the laboratory was a cause of these discordant reports. These findings lead us
the conclusion that the half-day training using the rapid and simple test was feasible for non-laboratory staffs to attain
enough proficiency to implement VCCT services for PMTCT in resource-limited settings, and that human error was more likely
to occur in laboratory before giving reports to counsellors. 相似文献
168.
The effect of calcium ion concentration on osteoblast viability, proliferation and differentiation in monolayer and 3D culture 总被引:9,自引:0,他引:9
Maeno S Niki Y Matsumoto H Morioka H Yatabe T Funayama A Toyama Y Taguchi T Tanaka J 《Biomaterials》2005,26(23):4847-4855
Our research group aims to develop an osteochondral composite using type II collagen gel with hydroxyapatite (HAp) deposited on one side. Soaking gels in Ca2+ and phosphate solution is indispensable to HAp deposition, so relationships between cell behavior and Ca2+ concentration were examined in two- and three-dimensional cultures. The present results indicate that 2-4 mM Ca2+ is suitable for proliferation and survival of osteoblasts, whereas slightly higher concentrations (6-8 mM) favor osteoblast differentiation and matrix mineralization in both 2- and 3-dimensional cultures. Higher concentrations (>10 mM) are cytotoxic. Purely from the perspective of calcium deposition, higher concentrations lead to increased accumulation of Ca2+. Culturing cells in phosphate-containing gel in media with Ca2+ also leads to time-dependent formation of HAp in the gel. Considering the viability of embedded cells, culturing scaffolds in media with Ca2+ concentrations around 5mM is useful for both HAp deposition and osteoblast behavior. 相似文献
169.
Babak S. Jahromi Yasuo Aihara Jinglu Ai Zhen-Du Zhang George Weyer Elena Nikitina Reza Yassari Khaled M. Houamed R. Loch Macdonald 《Neuroscience letters》2008
The pathogenesis of cerebral vasospasm after subarachnoid haemorrhage (SAH) involves sustained contraction of arterial smooth muscle cells that is maximal 6–8 days after SAH. We reported that function of voltage-gated K+ (KV) channels was significantly decreased during vasospasm 7 days after SAH in dogs. Since arterial constriction is regulated by membrane potential that in turn is determined predominately by K+ conductance, the compromised K+ channel dysfunction may cause vasospasm. Additional support for this hypothesis would be demonstration that K+ channel dysfunction is temporally coincident with vasospasm. To test this hypothesis, SAH was created using the double haemorrhage model in dogs and smooth muscle cells from the basilar artery, which develops vasospasm, were isolated 4 days (early vasospasm), 7 days (during vasospasm) and 21 days (after vasospasm) after SAH and studied using patch-clamp electrophysiology. We investigated the two main K+ channels (KV and large-conductance voltage/Ca2+-activated (KCa) channels). Electrophysiologic function of KCa channels was preserved at all times after SAH. In contrast, function of KV channels was significantly decreased at all times after SAH. The decrease in cell size and degree of KV channel dysfunction was maximal 7 days after SAH. The results suggest that KV channel dysfunction either only partially contributes to vasospasm after SAH or that compensatory mechanisms develop that lead to resolution of vasospasm before KV channels recover their function. 相似文献
170.
Normal human skin, malignant melanoma, nevocellular nevus, blue nevus, nevus of Ota and mongolian spot were immunohistochemically investigated on the localization of S-100 protein and neuron specific enolase (NSE). Tissues were fixed with buffered-formalin, processed with routine procedure and examined by the ABC technique. All cases of malignant melanoma and nevocellular nevus showed a relatively high amount of S-100 protein, but NSE was scantly demonstrated on about the half cases of these tumors. Blue nevus, nevus of Ota and mongolian spot revealed the presence of a small amount of S-100 protein and NSE on the half cases. Normal melanocytes were devoid of S-100 protein and NSE. Our results suggest that S-100 protein is the useful marker for diagnosis of malignant melanoma, and immunoreactive intensity for S-100 protein represents the differentiation of neural crest derived melanogenic cells and tumors. 相似文献