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991.
The role of subchondral insufficiency fracture in rapid destruction of the hip joint: a preliminary report 总被引:4,自引:0,他引:4
OBJECTIVE: The pathophysiology of rapidly destructive arthrosis of the hip joint (RDA) is unknown. The purpose of this study was to document cases of subchondral insufficiency fracture of the femoral head, which has similar clinicoradiologic features to those of early-stage RDA. METHODS: This study was based on a retrospective review of 11 cases of subchondral insufficiency fracture of the femoral head that were confirmed histopathologically and for which radiographs both at the onset of hip pain and at the time of surgery were available. RESULTS: All patients were > 60 years of age (range 61-78 years, mean age 69), and 9 were women. On plain radiographs, the normal joint space had undergone rapid narrowing and/or disappeared within 9 months (mean 5.8 months). Magnetic resonance imaging, available in 2 cases, showed a pattern of bone marrow edema from the upper portion of the femoral head to the intertrochanteric region, with an associated focal low-intensity band on T1 paralleling the articular surface. In all cases, evidence of subchondral insufficiency fracture was confirmed histopathologically. In addition, in the marrow space, there were several round-to-oval granulomatous foci, which consisted of amorphous debris, fragmented bone, and articular cartilage surrounded by reactive histiocytes and giant cells. All 11 patients were osteopenic, as shown both radiologically and histopathologically. CONCLUSION: Subchondral insufficiency fracture resulting from osteopenia may lead to a rapid breakdown of the hip joint. 相似文献
992.
Modulation by thymus-derived (T) cells of thyroid cell-stimulated prostaglandin E release by human peripheral blood mononuclear cells. 下载免费PDF全文
M Yamamoto N A Takai B Rapoport W E Hinds 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(12):6627-6631
Cultures of plastic-adherent, human peripheral blood mononuclear cells generated prostaglandin E (PGE). Culture of the adherent cells (predominantly monocytes) with human thyroid cells enhanced PGE accumulation in the medium, although to a lesser degree than occurs with unseparated blood mononuclear cells. Recombination of the adherent cells with monocyte-depleted, nonadherent cells restored both basal and thyroid cell-stimulated PGE generation to the levels seen with unseparated cells. Thymus-derived (T) cells, obtained by rosetting with sheep erythrocytes, similarly enhanced both the adherent cell basal PGE production as well as the increased PGE accumulation that occurs in the presence of thyroid cells (50-120% augmentation by the T cells). Significant augmentation of thyroid cell-stimulated PGE release by 10(5) adherent cells occurred with the addition of as few as 5 x 10(4) T cells. Culture medium transfer experiments and separation of cell types during culture by a semipermeable membrane provided evidence against the possibility that the adherent cells were releasing a factor that stimulated T-cell PGE generation or that T cells were releasing a factor that enhanced adherent cell PGE generation. The results suggest instead that this T-cell effect requires direct contact with the adherent cells. These data demonstrate the importance of human T cells in the release by adherent cells of PGE, a mediator of suppressor function by some immune cells. 相似文献
993.
Isolation of transforming sequences of two human lung carcinomas: structural and functional analysis of the activated c-K-ras oncogenes. 总被引:12,自引:11,他引:12 下载免费PDF全文
H Nakano F Yamamoto C Neville D Evans T Mizuno M Perucho 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(1):71-75
Human lung tumors PR310 and PR371 maintained in nude mice contain activated c-K-ras oncogenes detectable by the ability of their DNAs to induce the morphological transformation of NIH 3T3 mouse fibroblasts. Using phage libraries constructed with DNA from NIH 3T3 mouse fibroblast transformants, we have isolated human sequences that span greater than 40 kilobase pairs of the c-K-ras oncogene. Based on the conservation of these human sequences in mouse fibroblast transformants, we conclude that the transforming ability of the oncogene activated in these tumors resides within a 43- to 46-kilobase-pair DNA region. No clear differences were observed between the structures of the PR310 and PR371 cloned oncogene sequences. Nucleotide sequence analysis in concert with DNA transfection experiments suggests that the PR371 oncogene has been activated by a single base change in the first exon, which results in the substitution of cysteine for glycine in position 12 of the predicted amino acid sequence. The genetic alteration responsible for the transforming activity of the PR310 oncogene, however, does not reside in the first exon. These results indicate that the activation of the c-K-ras oncogene in human lung cancer can occur by different mutational events. 相似文献
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Masahiro Horiuchi Junko Endo Shin Akatsuka Tatsuya Hasegawa Eriko Yamamoto Tadashi Uno Sachiko Kikuchi 《Journal of Physical Therapy Science》2015,27(12):3711-3716
[Purpose] Forest walking may be effective for human health, but little information is
available about effects of energy expenditure on blood pressure responses after forest
walking. The aim of this study was to investigate the relationship between the activity
energy expenditure and changes in blood pressure in individuals after forest walking.
[Subjects] The subjects were 54 middle-aged and elderly people. [Methods] All subjects
walked in the forest for approximately 90 min. Blood pressure, salivary amylase, and the
Profile of Mood States were evaluated before and after forest walking, and activity energy
expenditure was monitored throughout forest walking. Subjects were divided into two groups
according to mean arterial pressure changes: a responder group (>5% decreases) and a
nonresponder group (<5%). [Results] Forest walking significantly reduced the mean
arterial pressure and improved the Profile of Mood States in both groups. Activity energy
expenditure was related to changes in mean arterial pressure in the responder group, while
this relation was not observed in the nonresponder group. Differential activity energy
expenditure did not strongly affect improvement of the Profile of Mood States.
[Conclusion] Greater walking-related greater activity energy expenditure might be required
to accentuate physiological beneficial effects on in middle-aged and aged people.
Furthermore, the forest environment per se can attenuate psychological stress.Key words: Hypertension, Profile of Mood States, Responder and nonresponder 相似文献
997.
Kazushi Yamamoto Shuang E Yu Hatakeyama Yu Sakamoto Tsuyoshi Tsuduki 《Journal of Clinical Biochemistry and Nutrition》2015,57(3):204-211
We examined the effect of a high-fat diet from senescence as a means of preventing malnutrition among the elderly. The senescence-accelerated mouse P8 was used and divided into three groups. The 6C group was given a normal diet until 6 months old. The 12N group was given a normal diet until 12 months old. The 12F group was given a normal diet until 6 months old and then a high-fat diet until 12 months old. In the oral fat tolerance test, there was a decrease in area under the curve for serum triacylglycerol level in the 12N group and a significant increase in the 12F group, suggesting that the attenuation of lipid absorption ability with aging was delayed by a high-fat diet from senescence. To examine this mechanism, histological analysis in the small intestine was performed. As a result, the degeneration of villi with aging was inhibited by the high-fat diet. There was also a significant decrease in length of villus in the small intestine in the 12N group and a significant increase in the 12F group. The high-fat diet from senescence inhibited the degeneration of villi with aging in the small intestine, and inhibited the attenuation of lipid absorption ability. 相似文献
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