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41.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
42.
Queenan JT Jr; Veeck LL; Toner JP; Oehninger S; Muasher SJ 《Human reproduction (Oxford, England)》1997,12(7):1573-1576
In-vitro fertilization patients (n = 15) at risk of ovarian
hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day
of human chorionic gonadotrophin administration and 25 or more follicles of
intermediate or large size) underwent aspiration of all follicles and
cryopreservation of all fertilized oocytes at the pronuclear stage.
Patients were monitored for up to 2 weeks post- retrieval. Subsequent
transfer of cryopreserved-thawed embryos was performed in programmed cycles
using exogenous oestrogen and progesterone for endometrial preparation. Two
patients (13%) developed OHSS necessitating hospitalization and vaginal
aspiration of ascitic fluid. Two other patients (13%) developed moderate
OHSS requiring ascitic fluid vaginal aspiration in the office setting, with
dramatic improvement of the condition. Subsequent transfer of
cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per
transfer and ongoing or delivery rates of 42 and 67% per transfer and per
patient respectively. By eliminating pregnancy potential with
cryopreservation of all prezygotes and examining the pregnancy potential
with subsequent cryopreserved-thawed transfers, it is concluded that OHSS
is reduced, but not eliminated for patients at risk. Subsequent transfer of
cryopreserved-thawed prezygotes in a programmed cycle with exogenous
steroids yields an excellent pregnancy rate.
相似文献
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46.
Five haplotypes account for fifty-five percent of ATM mutations in Brazilian patients with ataxia telangiectasia: seven new mutations 总被引:7,自引:0,他引:7
Coutinho G Mitui M Campbell C Costa Carvalho BT Nahas S Sun X Huo Y Lai CH Thorstenson Y Tanouye R Raskin S Kim CA Llerena J Gatti RA 《American journal of medical genetics. Part A》2004,(1):33-40
We have studied the molecular genetics of 27 Brazilian families with ataxia telangiectasia (AT). Five founder effect haplotypes accounted for 55.5% of the families. AT is an autosomal recessive disorder of childhood onset characterized by progressive cerebellar ataxia, ocular apraxia, telangiectasia, immunodeficiency, radiation sensitivity, chromosomal instability, and predisposition to cancer. The ATM gene spans more than 150 kb on chromosome region 11q23.1 and encodes a product of 3056 amino acids. The ATM protein is a member of the phosphatidylinositol 3-kinase (PI-3K) family of proteins and is involved in cell cycle control and DNA repair pathways. DNA was isolated from lymphoblastoid cell lines and haplotyped using four STR markers (D11S1818, NS22, D11S2179, D11S1819) within and flanking the ATM gene; all allele sizes were standardized in advance. In addition to the STR haplotypes, SNP haplotypes were determined using 10 critical polymorphisms. The entire gene was screened sequentially by protein truncation testing (PTT), single strand conformation polymorphism (SSCP), and then denaturing high performance liquid chromatography (dHPLC) to identify the disease-causing mutations. Of the expected 54 mutations, 50 were identified. All mutations but one, led to a truncated or null form of the ATM protein (nonsense, splice site, or frameshift). Five families (18.5%) carried a deletion of 3450nt (from IVS28 to Ex31), making this one of the two most common Brazilian mutations. Mutations were located throughout the entire gene, with no clustering or hotspots. Standardized STR haplotype analysis greatly enhanced the efficiency of mutation screening. 相似文献
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48.
A first step in the pilot-study undertaken as part of a research project on psychiatric morbidity--depression and organic brain syndrome--in the elderly population of Rio de Janeiro is described. The main objective is to "fine-tune" the instrument used (check list of DSM-III) and testing validity of the BOAS questionnaire (Brazilian version of Short-Care). The methodological aspects, and conceptual definitions are focused as well some procedures for the next stage of the project are suggested. 相似文献
49.
癌基因c-erbB-2在膀胱移行细胞癌中的扩增 总被引:2,自引:1,他引:1
0 引言 为探讨癌基因 c- erb B- 2的扩增与膀胱移行细胞癌(TCC)的关系 ,我们以斑点杂交的方法对 40例膀胱 TCC标本中 c- erb B- 2的扩增情况进行了检测 ,以期明确 c- erb B- 2扩增与膀胱 TCC病理分级及患者预后的关系 .1 材料和方法 40例膀胱 TCC患者术后石蜡包埋标本 ,随访 5~ 10 a. 11例正常膀胱粘膜石蜡标本作为对照 . c- erb B-c DNA p CER2 0 4质粒由东京大学提供 ,Bothringer缺口平移 DNA标记试剂盒及 32 P标记 d CTP购于北京福瑞公司 .所有石蜡标本经脱蜡及蛋白酶消化 ,以酚 /氯仿抽提 DNA,乙醇沉淀 .每份样品取… 相似文献
50.
Palmares J Castro-Correia J Coutinho MF Araújo D Delgado L 《Ocular immunology and inflammation》1995,3(2):99-106
The authors review the visual prognosis of 44 patients with Beh?et's disease referred to the Ophthalmology and Rheumatology Departments (Hospital S. Jo?o-one of the two major referral centers in Northern Portugal), due to ocular complaints or for routine examination, in the last ten years. All fulfilled the clinical criteria for diagnosis of Beh?et's disease. Twenty-six were male and 18 female, with mean age 37 years (range 23-66). The mean evolution time since the first clinical manifestations was ten years (range 1-21). Aphthous stomatitis (100%) and genital ulcers (77.3%) were the initial manifestations preceding eye involvement. HLA-B(51)(5) was present in 27 of 36 typed patients (75%). Ocular manifestations were present in 33 patients (75%)-22 patients with panuveitis, eight with hypopyon, four with chronic anterior uveitis and three with episcleritis. Mean age of onset of ocular complications was 32 years (range 20-54). Retinal vaso-occlusive vasculitis was diagnosed in 26 patients (22 with panuveitis and four with posterior uveitis). To prevent ocular relapses, all needed immunosuppression with corticosteroids (drops, depo or systemic), combined with cyclosporine A (CsA) (5 mg/kg/day) in 13 patients and with chlorambucil or cyclophosphamide in six patients, when sight threatening uveitis had previously been refractory to treatment with systemic steroids. The 13 patients under CsA were observed for a period ranging from eight months to five years. Lowdose CsA was found to abrogate the intraocular inflammation, was well tolerated and had no major adverse effects. Regardless of the type of treatment, 21% (14/66) of the eyes lost useful vision five to ten years after initial diagnosis. 相似文献