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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
981.
Philip J. Langlais PhD Mark L. Wardlow BS Hitoshi Yamamoto MD 《Pediatric neurology》1991,7(6):440-445
Cerebrospinal fluid (CSF) from 7 patients with infantile spasms (mean age: 6.7 months) was collected before and after treatment with adrenocorticotropic hormone (ACTH). The concentration of neurotransmitter metabolites was analyzed using high-performance liquid chromatography and compared to the metabolite concentration in the CSF from 7 age-matched controls (mean age: 6.1 months). Pretreatment levels of CSF 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid, 3-methoxy-4-hydroxyphenyl glycol (MHPG), and kynurenine were significantly lower in infantile spasm patients compared to controls. Following treatment, marked increases in 5-HIAA and decreases in kynurenine levels were observed in the CSF of the 5 infants whose seizures were eliminated or reduced by ACTH. In the 2 nonresponders 5-HIAA levels decreased. The level of MHPG was reduced slightly in 5 infants, including the 2 nonresponders, and was increased in 2 responders. CSF homovanillic acid levels increased in 4 infantile spasm infants and decreased in 3 following ACTH. These data demonstrate that the presence of seizures in infantile spasms is associated with a significant decrease in serotonergic activity and that elimination of seizures by ACTH is accompanied by increased serotonin turnover. The simultaneous increase of 5-HIAA and decrease of kynurenine, an alternate metabolite of tryptophan, suggests an underlying disturbance of tryptophan metabolism in infantile spasms. The possibility that elimination of seizures by ACTH may be related to decreased production of certain kynurenine metabolites, particularly quinolinic acid, is discussed. 相似文献
982.
B Kerboul J Le Saout C Lefevre D Miroux L Fabre J F Le Noac'h J M Rogero B Courtois 《Journal de chirurgie》1986,123(6-7):428-434
Results of three therapeutic modalities used for the treatment of a homogeneous series of patients with a Pouteau Colles fracture are analyzed. Orthopedic treatment provided deceiving results. Pinning was, on the contrary, very effective, intrafocal pinning with immediate mobilization of the wrist appearing perfectly effective. Few complications were reported in contrast to plastered immobilizations. Good results were obtained in 80% of cases and functional recovery was rapid, indicating that this method represents undoubted progress when compared with conventional therapies. 相似文献
983.
Lymphoscintigraphy in lymphedema: an aid to microsurgery 总被引:3,自引:0,他引:3
M Vaqueiro P Gloviczki J Fisher L H Hollier A Schirger H W Wahner 《Journal of nuclear medicine》1986,27(7):1125-1130
The role of lymphoscintigraphy, performed with 99mTc-labeled antimony sulfur colloid, in the diagnosis of lymphedema and as a test for selection of patients for microvascular operation was evaluated in 32 patients with primary and secondary lymphedema and four patients with other causes of leg edema. Lymphoscintigraphy clearly demonstrated if edema was of lymphatic origin. Five different image patterns were identified; abnormal image patterns could not be predicted from clinical history or physical findings. Quantitative evaluation of removal of the radioactive colloid from the injection site and appearance in lymph node sites and liver was of limited usefulness. Nine patients underwent various surgical procedures before or after lymphoscintigraphy. Lympho-venous anastomoses were possible only in patients who had patent lymph channels visible on lymphoscintigrams. Based on initial experience, lymphoscintigraphy seems to be useful to select patients for microvascular operation. 相似文献
984.
Allografts of CNS tissue possess a blood-brain barrier. II. Angiogenesis in solid tissue and cell suspension grafts 总被引:2,自引:0,他引:2
R D Broadwell H M Charlton P S Ebert W F Hickey Y Shirazi J Villegas A L Wolf 《Experimental neurology》1991,112(1):1-28
Angiogenesis and patency of blood vessels were analyzed qualitatively in solid CNS and peripheral tissue syngeneic, allogeneic, and xenogeneic grafts and in individual cell suspension grafts of astrocytes, fibroblasts, PC12, and three additional tumor cell lines placed intracerebrally in adult host mice. Postgrafting survival times were 1 day through 4 weeks. The patency of graft vessels was determined in sections from immersion-fixed tissues incubated to reveal the endogenous peroxidase activity of host red cells trapped within the lumen of blood vessels. Additionally, horseradish peroxidase (HRP) was administered intravenously to live hosts; HRP labels host brain and graft vessels on the luminal surface and reveals the presence or absence of a blood-brain barrier (BBB) within the grafts. The origins of blood vessels supplying solid tissue xenografts were identified immunohistochemically with primary antibodies against host (athymic AKR mice) and donor (fetal Lewis rats) major histocompatibility complex (MHC) class I. Blood vessels supplying solid CNS grafts at 1-7 days post-transplantation were identified ultrastructurally and possessed interendothelial tight junctional complexes; however, they were not perfused with either host blood or blood-borne HRP prior to 8 days. Graft vessels at 10 days were outlined consistently by peroxidase-positive red cells in immersion-fixed material and labeled with blood-borne HRP. These vessels provided a BBB to the circulating HRP and exhibited interendothelial tight junctions. Evidence of angiogenesis within solid anterior pituitary grafts and the variety of cell suspension grafts was obtained prior to 3 days post-transplantation in immersion-fixed preparations; the vessels, with the notable exception of those supplying astrocyte cell suspensions, failed to present a BBB to blood-borne peroxidase. Endothelia in the solid pituitary allografts and the PC12 cell grafts were highly fenestrated and exhibited open interendothelial junctions; those in the tumor and fibroblast cell grafts, for the most part, appeared nonfenestrated, and many possessed open interendothelial junctional complexes. Immunostaining for host and donor MHC class I revealed that donor blood vessels predominate over host vessels in CNS xenografts and supply pituitary xenografts exclusively; in both preparations, donor vessels were not identified within the host CNS. Because cell suspension grafts were derived from endothelia-free preparations grown in culture, blood vessels supplying these grafts were necessarily of host CNS origin and manifested a morphological transformation from a BBB to a non-BBB endothelium. The data suggest that angiogenesis in solid CNS grafts placed into the adult host CNS, compared to similarly placed solid peripheral tissue/cell suspension grafts, is not rapid.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
985.
986.
987.
T. A. Fedotcheva N. L. Shimanovskii A. I. Senderovich N. S. Chermnykh A. V. Semeikin V. M. Rzheznikov L. E. Golubovskaya G. S. Grinenko V. V. Banin P. V. Sergeev 《Pharmaceutical Chemistry Journal》2007,41(7):345-349
The hormonal compound with the highest cytostatic activity against MCF-7 tumor cells (human breast cancer, BC) and the lowest
activity against normal cells (rat skin fibroblasts) was sought among gestagens, androstenes, and antiestrogencytostatics.
It was found that antiestrogencytostatics and androstenes had the highest cytostatic activity against tumor cells whereas
gestagens and antiestrogencytostatics were least active against fibroblasts. Studies of the activity of the hormonal compounds
in combination with doxorubicin on the viability of MCF-7 and rat skin fibroblasts found that all investigated compounds with
the exception of dehydroepiandrosterone (DHEA) intensify the cytostatic activity of doxorubicin against tumor cells, the greatest
effect seen for antiestrogencytostatics. A chemoprotective effect of androstenes on normal cells was noted.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 7, pp. 3–7, July, 2007. 相似文献
988.
Ruben A. Mesa MD Alfonso Quintás-Cardama MD Srdan Verstovsek MD PhD 《Current hematologic malignancy reports》2007,2(1):25-33
Myelofibrosis with myeloid metaplasia (MMM) is currently classified as a classic (ie, BCR-ABL-negative) myeloproliferative
disorder characterized by anemia, multiorgan extramedullary hematopoiesis, constitutional symptoms, and premature death from
either leukemic transformation or other disease complications. Stem cell transplantation can be curative, but many patients
either are not appropriate candidates or do not choose to accept the significant risks associated with transplantation. Current
pharmacologic therapy has been beneficial mainly in terms of palliating disease-associated cytopenias, constitutional symptoms,
splenomegaly, and other organ damage from excess myeloproliferation. Novel treatment strategies are under investigation, including
targeted inhibition of JAK2V617F, the activating tyrosine kinase point mutation present in about half of patients with MMM. In this article, we review both
the old and new pharmacologic options for MMM. 相似文献
989.
990.