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61.
Temporal factors influence recovery of function after embryonic brain tissue transplants in adult rats with frontal cortex lesions 总被引:2,自引:0,他引:2
Adult rats with lesions of the medial frontal cortex received implants of frontal cortex taken from embryos on the 19th day of gestation and placed directly into the zone of injury at 7, 14, 30, or 60 days after initial surgery. Another group was given bilateral frontal lesions, followed 20 days later by a second small lesion to enhance the release of putative neurotrophic factors. They then received transplants 7 days after this second operation. All rats began postoperative training on a spatial alternation learning task within 4 days after the implants of fetal tissue. The brain-damaged rats with transplants at 7 or 14 days after surgery significantly improved postoperative acquisition of spatial alternation. Transplants made 30 or 60 days postoperatively had no effect; these groups were as impaired as those with lesions alone. The animals given a second, "priming" lesion after a 20-day delay, followed by implants of fetal brain tissue, performed as poorly as the group with frontal cortex lesions alone. 相似文献
62.
Kahn Jarl A.; von During Vidar; Sunde Arne; Sordal Terje; Molne Kare 《Human reproduction (Oxford, England)》1993,8(2):247-252
A cohort of 485 couples starting their first in-vitro fertilization(IVF) attempt between January, 1989 and February, 1991 inclusive,were followed until June 1, 1992. A total of 1086 treatmentcycles were initiated (mean 2.2, range 16). Of these,235 (21.8%) cycles were cancelled, giving a total of 851 embryoreplacements (mean 1.7, range 15). After IVF treatment,189 women have either delivered or have an ongoing pregnancyin the second or third trimester. This gives a baby take-homerate of 17.4% per started cycle and 22.2% per embryo replacement.For 91 (18.6%) of the couples, the treatment was abandoned priorto completion of the three scheduled IVF attempts and 57 (11.7%)of these had no completed IVF cycles. In the group of coupleswith reduced sperm quality, the delivery rate was significantlylower than that of the other groups. A total of 193 women hadembryos cryopreserved in at least one IVF cycle; 124 of thesewomen started a frozen embryo replacement cycle and 88 had atleast one cycle with replacement of frozen/thawed embryos, resultingin 25 deliveries/ongoing pregnancies. Due to the Norwegian lawon assisted procreation 65 (33.7%) of the women have had theirfrozen embryos thawed and discarded after 12 months of storage.The cryopreservation programme, with the limitations of theNorwegian law, gives a 5.2% increase in the baby take-home ratefor women entering the IVF programme, an increase of 13.2% inthe number of ongoing pregnancies/deliveries and an 11.6% increasein number of children/viable fetuses. A total of 214 women havedelivered or have ongoing pregnancies in the second or thirdtrimester. This represents 44.1% of the 485 women accepted forIVF treatment, irrespective of whether they were treated ornot, and 50.0% of those couples who completed at least one IVFcycle. 相似文献
63.
V. Candas J. P. Libert G. Brandenberger J. C. Sagot C. Amoros J. M. Kahn 《European journal of applied physiology》1986,55(2):113-122
Summary Five young unacclimatised subjects were exposed for 4 h at 34 C (10 C dew-point temperature and 0.6 m · s–1 air velocity), while exercising on a bicycle ergometer: 25 min work — 5 min rest cycles for 2 hours followed by 20 min work — 10 min rest cycles for two further hours. 5 experimental sessions were carried out: one without rehydration (NO FLUID) resulting in 3.1% mean loss of body weight ( Mb), and four sessions with 20 C fluid ingestion of spring water (WATER), hypotonic (HYPO), isotonic (ISO) and hypertonic (HYPER) solutions to study the effects of fluid osmolarity on rehydration. Mean final rehydration (±SE) after fluid intake was 82.2% (±1.2). Heart rate was higher in NO FLUID while no difference among conditions was found in either Mb or hourly sweat rates. Sweating sensitivity was lowest in the dehydration condition, and highest in the WATER one. Modifications in plasma volume and osmolarity demonstrated that NO FLUID induced hyperosmotic hypovolemia, ISO rehydration rapidly led to plasma isoosmotic hypervolemia, while WATER led to slightly hypoosmotic normovolemia.It is concluded that adequate rehydration through ingestion of isotonic electrolyte-sucrose solution, although in quantities much smaller than evaporative heat loss, rapidly restored and expanded plasma volume. While osmolarity influenced sweating sensitivity, the plasma volume changes ( PV) within the range –6% PV+4% had little effect on temperature adjustments in our conditions. 相似文献
64.
Posthuma D de Geus EJ Neale MC Hulshoff Pol HE Baaré WEC Kahn RS Boomsma D 《Behavior genetics》2000,30(4):311-319
The hunt for genes influencing behavior may be aided by the study of intermediate phenotypes for several reasons. First, intermediate phenotypes may be influenced by only a few genes, which facilitates their detection. Second, many intermediate phenotypes can be measured on a continuous quantitative scale and thus can be assessed in affected and unaffected individuals. Continuous measures increase the statistical power to detect genetic effects (Neale et al., 1994), and allow studies to be designed to collect data from informative subjects such as extreme concordant or discordant pairs. Intermediate phenotypes for discrete traits, such as psychiatric disorders, can be neurotransmitter levels, brain function, or structure. In this paper we conduct a multivariate analysis of data from 111 twin pairs and 34 additional siblings on cerebellar volume, intracranial space, and body height. The analysis is carried out on the raw data and specifies a model for the mean and the covariance structure. Results suggest that cerebellar volume and intracranial space vary with age and sex. Brain volumes tend to decrease slightly with age, and males generally have a larger brain volume than females. The remaining phenotypic variance of cerebellar volume is largely genetic (88%). These genetic factors partly overlap with the genetic factors that explain variance in intracranial space and body height. The applied method is presented as a general approach for the analysis of intermediate phenotypes in which the effects of correlated variables on the observed scores are modeled through multivariate analysis. 相似文献
65.
The search for a mechanism for red cell enzyme deficiency associated with congenital hemolytic anemia, requires one to determine the kinetic and thermodynamic properties of the enzyme reaction and study the physico-chemical and immunological characteristics of the protein which supports enzyme activity. The technique of iso-electric focalisation and the use of specific anti-enzyme antibodies, is the reason for recent progress in the understanding of the mechanism of these deficiencies. Examples of application of these techniques are given in relation to glucose-6-dehydrogenase, pyruvate kinase, glucose phosphate isomerase, phosphofructokinase and phosphoglycerate kinase of deficiencies showing the multiplicity of the molecular mechanisms. 相似文献
66.
67.
Clavert P Kempf JF Wolfram-Gabel R Kahn JL 《Surgical and radiologic anatomy : SRA》2005,27(5):385-388
Different anterosuperior aspects of the glenoid labrum have already been described and are thought to be normal anatomical
variations. The goals of this study were first to characterize these anterosuperior labral morphologies and then to analyze
their variations in function of the patients’ age. One hundred shoulder arthroscopies were recorded to study the macroscopic
characteristics of the anterosuperior labrum of the glenohumeral joint and its relationships with the proximal insertion of
the tendon of the long head of the biceps. Then, patients were divided into two groups in function of their age (below and
over 30 years old). Morphological modifications of the labrum were found in function of the age of the patient with an increase
of the nonpathologic “mobile labrum” type after 30 years (P=0.0423). Therefore a mobile and loosely attached superior labrum should not always be considered as abnormal, especially
in case of patient older than 30 years. 相似文献
68.
69.
Ivemark syndrome is a rare sporadic or autosomal recessive disorder characterized by pancreatic fibrosis, renal dysplasia and hepatic dysgenesis. There have been no data describing the renal changes during embryologic development in this syndrome. In this report, we document the pathological findings of the kidney in three subjects with Ivemark syndrome: 6 months, 21 weeks and 16 weeks, respectively. Kidneys of subjects and age-matched controls were examined by light microscopy and immunohistochemically for cytokeratin, AE1/AE3 and epithelial membrane antigen. Renal dysplasia in Ivemark syndrome becomes apparent at 16 weeks of gestation and progresses thereafter in severity. It is characterized by disturbance in glomerular differentiation, delay in tubular differentiation and abnormal expression of epithelial markers in glomeruli and tubules. Cytokeratin and epithelial membrane antigen expression of cysts is similar to that of the collecting ducts. 相似文献
70.
Deletion of the long arm of the Y chromosome and review of Y chromosome abnormalities 总被引:3,自引:0,他引:3
We report on a patient whose karyotype is 45,X/46,X,del(Y) (pter----q11.212). We also present a review of literature on the Y chromosome in which evidence is presented that there are genes on the Y chromosome that prevent Ullrich-Turner syndrome manifestations; aid in testes maturation and spermatogenesis; and affect height, tooth size, and bone maturation. 相似文献