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41.
Birth injury to the spinal cord 总被引:3,自引:0,他引:3
11 cases of children with birth injury to the spinal cord born between 1960 and 1970 are presented in review and compared to about 200 previously published cases. 8 children presented at delivery with one or both feet and 2 with breech. 9 of these infants were born by difficult extraction and needed resuscitation due to primary asphyxia. One child had an easy vertex delivery without evident risk. Diagnosis was established within the first days of life, based on flaccid motor and sensory paralysis below a defined level, mostly in the cervical or upper thoracic spine, with bladder and bowel paralysis, and confirmed by autopsy or by follow-up study. One child with disruption of the spinal cord above C4 survived only a few hours despite artificial ventilation. 4 children died within the first three years of life, 3 of them due to acute pneumonia. 5 of 6 surviving children were followed regularly and are now 10 to 18 years old. They are ambulant with crutches and are well integrated in their families. 4 children attend normal school, and one girl gets special training for mentally retarded children. 相似文献
42.
Platelet adhesion and thrombus formation on subendothelium in platelets deficient in glycoproteins IIb-IIIa, Ib, and storage granules 总被引:22,自引:1,他引:22
Patients whose platelets are deficient in glycoprotein (GP) Ib, IIb- IIIa (thrombasthenia), or granule substances (storage pool deficiency, SPD) were studied to define further the properties of platelets that mediate platelet adhesion and thrombus formation on subendothelium. Both nonanticoagulated and citrated blood were exposed to everted, de- endothelialized rabbit vessel segments under controlled flow conditions and shear rates varying from 650 to 3,300 sec-1. Morphometry was used to measure platelet thrombus dimensions and the percentage of the subendothelial surface covered with contact (C) or spread (S) platelets. Adhesion was defined as C + S. The results in SPD demonstrated (1) reduced thrombus dimensions in delta-SPD (pure dense granule deficiency) in proportion to the magnitude of the dense granule defect; (2) an even greater reduction in thrombus dimensions in patients with combined deficiencies of alpha and dense granules (alpha delta-SPD); and (3) impaired platelet adhesion at several conditions in alpha delta-SPD and, in delta-SPD, a hematocrit-dependent impairment of adhesion in citrated blood at 2,600 sec-1. In thrombasthenia, platelets were present as a monolayer on the subendothelial surface in both nonanticoagulated and citrated blood, indicating an absolute requirement for GPIIb-IIIa in promoting platelet-platelet interaction at all shear rates and perfusion times. Two types of abnormalities in platelet-vessel wall interactions were observed. In nonanticoagulated blood, the percentage of platelets in the C phase was consistently increased at all shear rates, but C + S values were normal. These observations indicate that platelets deficient in GPIIb-IIIa do not spread normally on the subendothelial surface exposed to nonanticoagulated blood. With citrated blood, the C + S value in thrombasthenia was reduced at both 800 and 2,600 sec-1, as in von Willebrand's disease, and a similar degree of reduction (about 50%) was observed in normal blood treated with a monoclonal antibody to GPIIb- IIIa. The findings, together with theoretical considerations, are consistent with an hypothesis that GPIIb-IIIa mediates the spreading of platelets on subendothelium following the initial attachment through GPIb and that GPIIb-IIIa may be considered an adhesion site on the platelet membrane. Abnormalities of GPIIb-IIIa may, depending on the conditions of study, result in either increased values of C platelets or decreased values of C + S. The results of the study further suggest that a complex interaction of platelet granule factors and membrane GP mediate platelet adhesion and thrombus formation. 相似文献
43.
44.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献
45.
46.
Background
Due to the lack of a suitable and economic test for the analysis of the polymorphism at codon 167, we developed a new PCR-RFLP technique, based on a modified forward primer (UT-HC167 MF-primer), to identify simultaneously the SNPs at codons 167 and 200 of isotype 1 β-tubulin gene of Haemonchus contortus.Methods
There already are several safe and easy methods for identification of point mutations at codons 198 and 200. Due to the lack of a reliable and easy method for the detection of the single nucleotide polymorphism (SNP) at codon 167, we developed an innovative PCR-RFLP technique based on a modified forward primer (UT-HC167 MF-primer), in which the nucleotide T at the position 443 was substituted through a nucleotide A creating a restriction site for restriction endonuclease SnaB I in the nucleotide sequences including codon 167. A total of 138 adult male H. contortus were collected from three different geo-climatic areas of Iran. The isolated genomic DNA of each single worm was amplified by PCR using primers flanking codon 167. The PCR product (527 bp) was then amplified by semi-nested PCR using the UT-HC167 MF-primer and the reverse primer achieving a PCR product of 451 bp in length. This PCR product was subsequently digested with the restriction endonucleases SnaB I and TaaI for analysis of the mutations at codons 167 and 200, respectively.Results
All worms had two alleles encoding for phenylalanine (BZss homozygote) for both codons.Conclusion
Using the UT-HC167 MF-primer and a suitable reverse primer designed upstream from codon 200, it is possible to amplify a PCR product which can be used for analysis of the SNPs at all three mentioned codons using RFLP. 相似文献47.
David P. Parsons M.D. Harry A. Kahn M.D. M.P.H. John T. Isler M.D. Dr. Richard P. Billingham M.D. 《Diseases of the colon and rectum》1999,42(7):959-960
PURPOSE: An original case of rectal injury after a personal watercraft accident is reported. Principles of rectal trauma management are discussed. METHODS: We present a case of a rectal injury after a fall from a personal watercraft. Rigid sigmoidoscopy and a water-soluble contrast enema documented a posterior rectal tear. The patient was managed by diversion, drainage, and administration of antibiotics. RESULTS: The patient's rectal tear healed without complication. CONCLUSION: To our knowledge, this is the first reported case of an injury to the rectum as a result of a personal watercraft accident. A high suspicion of rectal injury must be maintained in victims who have fallen from the back of a personal watercraft. Treatment of a rectal injury should follow the basic principles of drainage, diversion, and administration of antibiotics, but variations in traditional management may be appropriate. Finally, preventative methods including wearing protective clothing, and possible modification to the watercraft to reduce risk of injury should be considered. 相似文献
48.
49.
H Isler 《Headache》1986,26(1):27-29
SYNOPSIS
Studies of forgotten non-English and Latin texts often show that new discoveries are not quite new.Are these studies futile, or do they make sense? Some examples of missing references, found byapplied history of medicine, may provide an answer. 相似文献
Studies of forgotten non-English and Latin texts often show that new discoveries are not quite new.Are these studies futile, or do they make sense? Some examples of missing references, found byapplied history of medicine, may provide an answer. 相似文献
50.
The purpose of this report was to determine the required number of electrodes to record the infant and adult electroencephalogram (EEG) with a specified amount of spatial sampling error. We first developed mathematical theory that governs the spatial sampling of EEG data distributed on a spherical approximation to the scalp. We then used a concentric sphere model of current flow in the head to simulate realistic EEG data. Quantitative spatial sampling error was calculated for the simulated EEG, with additive measurement noise, for 64, 128, and 256 electrodes equally spaced over the surface of the sphere corresponding to the coverage of the human scalp by commercially available "geodesic" electrode arrays. We found the sampling error for the infant to be larger than that for the adult. For example, a sampling error of less than 10% for the adult was obtained with a 64-electrode array but a 256-electrode array was needed for the infant to achieve the same level of error. With the addition of measurement noise, with power 10 times less than that of the EEG, the sampling error increased to 25% for both the infant and adult, for these numbers of electrodes. These results show that accurate measurement of the spatial properties of the infant EEG requires more electrodes than for the adult. 相似文献