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81.
BACKGROUND/AIMS: Reflux of bile to the oesophagus has been shown to be of importance in the development of gastro-oesophageal reflux disease. This study aims to assess oesophageal motility patterns in relation to acid and bile reflux to the oesophagus. METHODS: Forty-nine subjects with and without reflux disease underwent 24-hour ambulatory recordings of oesophageal pH, bile and 3-channel manometry. Gastroscopy was performed to assess severity of oesophagitis. The percentage of effective peristaltic contractions (oesophageal contractions with a peristaltic pattern and a pressure >30 mm Hg) were correlated to the degree of acid and bile reflux. Ten subjects were re-evaluated within 2 years post-fundoplication. RESULTS: Acid and bile reflux were associated with fewer effective contractions (R(2) = 0.07, p = 0.06 and R(2) = 0.21, p = 0.008, respectively). However, in a multivariate model including acid, bile, age and gender dependency, only bile could show a systematic effect on the variation in percentage of effective peristaltic contractions (R(2) = 0.22, p = 0.001). One year after laparoscopic fundoplication, 24-hour oesophageal motility was unchanged. CONCLUSION: Reflux of duodenal juice to the oesophagus is associated with less effective oesophageal motility, which in turn can perpetuate the disease by less effective oesophageal clearance of bile and acid. The reduced oesophageal motility is not reversed by fundoplication. 相似文献
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Eight adult patients with sickle cell anemia were followed over a 6-mo period. During this time all patients had elevated plateletcounts, 1.7-fold (mean, 438,398 +/- 86,223), and megathrombocyte numbers, 2.3-fold (mean, 79,535 +/- 38,907), during asymptomatic periods. These data are interpreted as suggesting that the elevated platelets and megathrombocytes in asymptomatic sickle cell patients result from lack of splenic sequestration. During three crises in two patients, both megathrombocyte number and platelet count fell significantly. It is speculated that platelets may be associated with the pathology in this disease. Platelet function studies performed during crises, therefore, must take into account the number of megathrombocytes. 相似文献
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Robyn Westmacott Morris Freedman Sandra E. Black Kathryn A. Stokes Morris Moscovitch 《Cognitive neuropsychology》2013,30(2-4):353-378
Abstract Semantic knowledge of famous names and words that entered popular North American culture at different times in the 20th century was examined in 16 patients with mild-to-moderate Alzheimer's disease (AD), 12 of whom were re-tested 1 year later. All patients showed evidence of temporally graded memory loss, with names and words from the remote past being relatively better preserved than recent names and words. There was considerable between-patient variability with respect to severity of semantic impairment. Most patients exhibited losses extending back 30-40 years; however, two mildly impaired (MMSE >28) patients showed deficits restricted to the last 10-15 years. At the 1-year follow-up, patients not only exhibited more severe deficits overall, but the temporally graded period of loss extended further back in time, suggesting that this deficit reflects a loss of previously intact knowledge and not merely faulty encoding or lack of exposure to the material. The extensive period of graded semantic loss exhibited by most patients contrasts with the temporally limited retrograde semantic loss typical of medial temporal lobe amnesia. We propose that short periods of temporally graded semantic memory loss can be explained by damage to medial temporal structures, but that extensive periods of graded loss occur only with additional damage to neocortical tissue. This pattern contrasts with that of autobiographical memory loss, which is often ungraded and extends for the person's entire lifetime, even when damage is restricted to the medial temporal lobes. 相似文献
87.
Abstract Speech error data and empirical studies suggest that the scope of planning is larger for semantic than for phonological form representations in speech production. Previous results have demonstrated that some patients show dissociable impairments in the retention of semantic and phonological codes. The effect of these STM deficits on speech production was investigated using a phrase production paradigm that manipulated the semantic relatedness of the words in the phrase. Subjects produced a conjoined noun phrase to describe two pictures (e.g., "ball and hat") or produced the same phrases in response to pairs of written words. For the picture naming condition, control subjects showed an interference effect for semantically related pictures relative to unrelated pictures. This interference effect was greatly exaggerated for two patients with semantic short-term memory deficits but not for a patient with a phonological STM deficit. For the written words, control subjects showed a small facilitatory effect for the onset of phrases containing semantically related words. One of the patients with a semantic STM deficit who was tested on picture naming was also tested on these materials and showed a small facilitatory effect within the range of controls. The findings support the contention that speech planning is carried out at a phrasal level at the lexical-semantic level and that the capacities that support semantic retention in list recall support speech production planning. 相似文献
88.
David S. Freedman Jack Wang Cynthia L. Ogden John C. Thornton Zuguo Mei Richard N. Pierson 《Annals of human biology》2013,40(2):183-194
Background: Although the body mass index (BMI, kg?m?2) is widely used as a measure of adiposity, it is a measure of excess weight, rather than excess body fat. It has been suggested that skinfold thicknesses be measured among overweight children to confirm the presence of excess adiposity.Objective: The present study examined the additional information provided by skinfold thicknesses on body fatness, beyond that conveyed by BMI-for-age, among healthy 5- to 18-years old (n?=?1196).Methods and procedures: Total body dual-energy X-ray absorptiometry (DXA) provided estimates of % body fat, and the sum of two skinfolds (triceps and subscapular) was used as an indicator of the overall skinfold thickness.Results: As assessed by the multiple R2s and the residuals of various regression models, information on the skinfold sum significantly (?p?<?0.001) improved the prediction of body fatness beyond that obtained with BMI-for-age. For example, the use of the skinfold sum, in addition to BMI-for-age, increased the multiple R2s for predicting % body fat from 0.81 to 0.90 (boys), and from 0.82 to 0.89 (girls). The use of the skinfold sum also reduced the overall prediction errors (absolute value of the residuals) for % body fat by 20–30%, but these reductions varied substantially by BMI-for-age. Among overweight children, defined by a BMI-for-age ≥95th percentile, the skinfold sum reduced the predication errors for % body fat by only 7–9%.Conclusions: Although skinfold thicknesses, when used in addition to BMI-for-age, can substantially improve the estimation of body fatness, the improvement among overweight children is small. 相似文献
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Clarissa Romez Kenn Freedman David Zaritzky Joshua W. Brown 《Explore (New York, N.Y.)》2021,17(1):79-83
An 18-year-old female lost the majority of her central vision over the course of three months in 1959. Medical records from 1960 indicate visual acuities (VA) of less than 20/400 for both eyes corresponding to legal blindness. On fundus examination of the eye there were dense yellowish-white areas of atrophy in each fovea and the individual was diagnosed with juvenile macular degeneration (JMD). In 1971, another examination recorded her uncorrected VA as finger counting on the right and hand motion on the left. She was diagnosed with macular degeneration (MD) and declared legally blind. In 1972, having been blind for over 12 years, the individual reportedly regained her vision instantaneously after receiving proximal-intercessory-prayer (PIP). Subsequent medical records document repeated substantial improvement; including uncorrected VA of 20/100 in each eye in 1974 and corrected VAs of 20/30 to 20/40 were recorded from 2001 to 2017. To date, her eyesight has remained intact for forty-seven years. 相似文献
90.
Lestou VS Gascoyne RD Sehn L Ludkovski O Chhanabhai M Klasa RJ Husson H Freedman AS Connors JM Horsman DE 《British journal of haematology》2003,122(5):745-759
In order fully to identify secondary chromosomal alterations, such as duplications, additions and marker chromosomes that remained unresolved by G banding, 60 cases of t(14;18)-positive follicular lymphoma (FL) were analysed by multicolour karyotyping techniques [multicolour fluorescence in situ hybridization (MFISH)/multicolour banding for chromosome 1 (MBAND1)]. A total of 165 additional structural chromosomal aberrations were delineated. An increased frequency of chromosomal gains involving X, 1q, 2, 3q27-q29, 5, 6p11-p21, 7, 8, 11, 12, 14q32, 17q, 18 and 21 and deletions of 1p36, 3q28-q29, 6q, 10q22-q24 and 17p11-p13 was revealed by the MFISH/MBAND1 analysis. Balanced translocations other than t(14;18) were uncommon, whereas unbalanced translocations were numerous. Deletion of 1p36 and duplication of 1p33-p35, 1p12-p21 and 1q21-q41 were regularly involved in chromosome 1 alterations, seen in 53% of the cases. A strong correlation was demonstrated between gains of individual chromosomal bands and increased gene expression, including 1q22/MNDA, 6p21/CDKN1A, 12q13-q14/SAS, 17q23/ZNF161, 18q21/BCL2 and Xq13/IL2RG. Unfavourable overall survival was associated with del(1)(p36) and dup(18q). These data support the notion that translocation events are primarily responsible for FL disease initiation, whereas the unbalanced chromosomal gains and losses that mirror the gene expression patterns characterize clonal evolution and disease progression, and thus provide further insights into the biology of FL. 相似文献