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排序方式: 共有461条查询结果,搜索用时 78 毫秒
401.
Arrhythmias in general practice: diagnostic value of patient characteristics, medical history and symptoms 总被引:3,自引:3,他引:0
Zwietering PJ; Knottnerus JA; Rinkens PE; Kleijne MA; Gorgels AP 《Family practice》1998,15(4):343-353
BACKGROUND: Complaints possibly caused by arrhythmias are frequently seen
in general practice. It is unclear to what extent such complaints can
differentiate between arrhythmias and other pathology in general practice.
OBJECTIVES: We aimed to assess the value of symptoms (a) in diagnosing
arrhythmias in general practice and (b) in identifying patients with
clinically relevant arrhythmias. METHOD: During a 2-year period, a
structured history from 762 patients with new complaints possibly related
to an arrhythmia was taken by the GP, and a transtelephonic
electrocardiogram (ECG) was made. RESULTS: In 28.3% of the patients,
arrhythmias were detected and 8.8% were clinically relevant. Several
patient characteristics, symptoms and medical history findings have high
predictive values in diagnosing arrhythmias. In the logistic regression
analysis, age and, to a lesser extent, male gender, palpitations and
dyspnoea during consultation and the use of cardiovascular drugs are
associated with the presence of arrhythmias. In detecting clinically
relevant arrhythmias the same parameters apart from gender are important,
as well as a history of arrhythmias. The use of central nervous system
medication and frequent psychosomatic complaints are negatively associated
with the presence of clinically relevant arrhythmias. CONCLUSIONS: In
general practice, patient characteristics, symptoms and medical history
findings can be used in the detection of arrhythmias and the assessment of
their severity. They can help in the decision of whether to make an ECG
recording.
相似文献
402.
403.
The relation of human erythrocyte Rh0(D) to Du sites is an important unresolved question in the field of immunohematology. To compare the immunological reactivity of Rh0(D)-positive and Du erythrocytes, the binding characteristics of two anti-Rh0(D) antisera to human Rh0(D)- positive and Du ("low-grade") erythrocytes were studied. 14C-Protein A and direct antibody-labeled techniques were used to generate binding curves and to derive double-reciprocal plots. The results show that the number of antigen sites differ by a factor of 10 to 15 between the Rh0(D)-positive and Du red cells, but that the dissociation constants between anti-Rh0(D) and the Rh0(D) and Du antigens are indistinguishable when studied by the two labeling methods and two different anti-Rh0(D) antibodies. The extent of binding to 112 different Du samples showed a normal distribution and was independent of apparent phenotype. These data suggest immunologic identity of Rh0(D) and Du ("low-grade") sites and that the difference between the antigens of Rh0(D) and Du cells is quantitative only. The data are incompatible with the "missing mosaic" and gene interaction theories of mechanism. 相似文献
404.
Wang ML; Hussey DH; Vigliotti AP; Benda J; Wen BC; Doornbos JF; Anderson B 《Radiology》1987,165(2):561-565
Between 1960 and 1979, 41 patients with adenocarcinoma of the endometrium who were poor surgical risks were treated with radiation therapy at the University of Iowa. Local tumor control was achieved in 78% of the patients, 5% manifested complications, and 46% survived 5 years ("uncorrected" 5-year survival rate). Intercurrent disease was the major cause of death (54%), and intrauterine recurrence (22%) was the most frequent recurrence. Intraperitoneal spread (12%) occurred as commonly as hematogenous metastases (12%). Three of nine local failures occurred after 5 years. Local control rates correlated well with clinical stage, and the survival rates correlated well with the stage and grade of the tumor. Local tumor control was achieved in 95% of patients who received greater than 7,000 mg-h intracavitary radium, compared with 63% of patients treated with less than 7,000 mg-h. 相似文献
405.
The sonographic records of 27 children who underwent a Cohen ureteroneocystostomy were reviewed. In 13 children (48%) sonograms demonstrated an echogenic, nonacoustically shadowing structure at or just above the trigone that was fixed in position within the bladder wall and covered by intact mucosa. This constellation of sonographic findings, which represent the submucosal segment of the reimplanted ureter, produces a "tunnel sign." Awareness of this appearance will enable the sonographer to better evaluate children who have undergone surgical procedures on the bladder. 相似文献
406.
Linkage and physical mapping of X-linked lissencephaly/SBH (XLIS): a gene causing neuronal migration defects in human brain 总被引:6,自引:2,他引:6
Ross ME; Allen KM; Srivastava AK; Featherstone T; Gleeson JG; Hirsch B; Harding BN; Andermann E; Abdullah R; Berg M; Czapansky-Bielman D; Flanders DJ; Guerrini R; Motte J; Mira AP; Scheffer I; Berkovic S; Scaravilli F; King RA; Ledbetter DH; Schlessinger D; Dobyns WB; Walsh CA 《Human molecular genetics》1997,6(4):555-562
While disorders of neuronal migration are associated with as much as 25% of
recurrent childhood seizures, few of the genes required to establish
neuronal position in cerebral cortex are known. Subcortical band
heterotopia (SBH) and lissencephaly (LIS), two distinct neuronal migration
disorders producing epilepsy and variable cognitive impairment, can be
inherited alone or together in a single pedigree. Here we report a new
genetic locus, XLIS, mapped by linkage analysis of five families and
physical mapping of a balanced X;2 translocation in a girl with LIS.
Linkage places the critical region in Xq21-q24, containing the breakpoint
that maps to Xq22.3-q23 by high-resolution chromosome analysis. Markers
used for somatic cell hybrid and fluorescence in situ hybridization
analyses place the XLIS region within a 1 cM interval. These data suggest
that SBH and X-linked lissencephaly are caused by mutation of a single
gene, XLIS, that the milder SBH phenotype in females results from random
X-inactivation (Lyonization), and that cloning of genes from the breakpoint
region on X will yield XLIS.
相似文献
407.
Immediate skin hypersensitivity to various inhalant allergens was present in 59% of 123 children with cystic fibrosis (CF), a much higher percentage than in the general population. This is consistent with the idea that atopy arises as a result of impaired handling of antigen at mucosal surfaces. The allergic CF children had more chest infections, a worse chest x-ray appearance, and lower peak expiratory flow rates. Allergic diseases were also frequent in the CF obligate heterozygotes (32% of mothers and 26% of fathers). It is suggested that the heterozygotes may also have a mucosal abnormality resulting in defective antigen handling. 相似文献
408.
409.
410.
2-(2-噻吩)乙胺的合成 总被引:4,自引:0,他引:4
目的:改进药物中间体2-(2-噻吩)乙胺的合成方法,使之适合工业化生产。方法:以噻吩为原料,经Vilsmeier反应制得噻吩甲醛,再将Darzen反应、水解、脱羧、与盐酸羟胺缩合等用一锅煮方法制得噻吩-2-乙醛肟,再经Raney Ni还原得目的物2-(2-噻吩)乙胺。结果:总收率可达70.09%,略高于文献。结论:此方法适合工业化生产。 相似文献