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111.
112.
S L Mackenzie G S Sundaram H S Sodhi 《Clinica chimica acta; international journal of clinical chemistry》1973,43(2):223-229
A technique is described for the detection of free fatty acids, triglycerides, wax esters and cholesterol esters on thin-layer Chromatographic plates. The fatty acids present in each fraction can be recovered from the plates after detection and quantitatively measured by gas-liquid chiomatography. This procedure has been sucessfully applied to the analysis of skin surface lipids. 相似文献
113.
Racial differences in the incidence of limb loss secondary to peripheral vascular disease: a population-based study 总被引:1,自引:0,他引:1
Dillingham TR Pezzin LE Mackenzie EJ 《Archives of physical medicine and rehabilitation》2002,83(9):1252-1257
OBJECTIVE: To evaluate racial differences in limb loss caused by peripheral vascular disease in a diverse, statewide population. DESIGN: Retrospective analysis of a cohort of dysvascular amputees. SETTING: Maryland State Hospital Discharge Data from 1986 to 1997. PARTICIPANTS: Persons with a procedure code for lower-limb amputation (ICD9-CM code 84.11-.19) were identified. Patients with limb loss because of trauma, malignancy, or congenital anomalies were excluded. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Incidence rates standardized for age, gender, and race; and time trends. RESULTS: There were 27,149 discharges with dysvascular amputations, yielding an average annual rate of 44.3 per 100,000 persons. Incidence rates for dysvascular amputations increased from 41.4 per 100,000 in 1986 to 47.2 per 100,000 in 1997. For all levels of amputation, annual incidence rates among African Americans were considerably higher than those of other persons. African Americans were 2 to 4 times more likely to lose a lower limb than white persons of similar age and gender. CONCLUSIONS: Rising rates of lower-limb amputations in the general population combined with disproportionately higher rates among African Americans are concerning and warrant further investigation into their underlying causes and consequences. 相似文献
114.
Purpose : The Home Falls and Accidents Screening Tool (HOME FAST) was designed as part of a comprehensive health assessment instrument to measure falls risk for older people within their home environment. This paper describes the evaluation of the inter-rater reliability of the HOME FAST.
Method : Forty home visits were undertaken, in urban and rural settings of the UK, by pairs of raters, one of whom was an expert rater. Occupational therapists, occupational therapy assistants and a social worker rated each home using the HOME FAST concurrently with an expert rater. The kappa statistic was used to determine the degree of agreement between pairs of raters.
Results : The overall kappa value for the checklist was 0.62, indicating a fair to good level of agreement between raters. 'Hazardous outside paths' was the only item that demonstrated poor agreement (kappa=0.30). The expert rater consistently identified more hazards than the other raters, and the level of agreement was stable between raters irrespective of the number of hazards present in the homes visited.
Conclusions : Definitions of non-applicable household features and improving the objectivity of the operational definitions for recognizing hazards that demand more qualitative judgements will enhance the reliability of the HOME FAST. 相似文献
Method : Forty home visits were undertaken, in urban and rural settings of the UK, by pairs of raters, one of whom was an expert rater. Occupational therapists, occupational therapy assistants and a social worker rated each home using the HOME FAST concurrently with an expert rater. The kappa statistic was used to determine the degree of agreement between pairs of raters.
Results : The overall kappa value for the checklist was 0.62, indicating a fair to good level of agreement between raters. 'Hazardous outside paths' was the only item that demonstrated poor agreement (kappa=0.30). The expert rater consistently identified more hazards than the other raters, and the level of agreement was stable between raters irrespective of the number of hazards present in the homes visited.
Conclusions : Definitions of non-applicable household features and improving the objectivity of the operational definitions for recognizing hazards that demand more qualitative judgements will enhance the reliability of the HOME FAST. 相似文献
115.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
116.
Summary. A tymovirus isolated from Malaysian crops of Calopogonium mucunoides has been shown to have virions that are serologically indistinguishable from those of clitoria yellow vein tymovirus. We
have sequenced the virion protein (VP) gene of the virus and have found that although it is a member of the cluster that includes
CYVV, it is the most distinct member of that cluster (< 62% sequence identity with all the others), and is clearly a separate
species, which we propose should be named calopogonium yellow vein virus. Most of the serological specificity of the virions
of tymoviruses seems to reside in the C-terminal hexapeptide of the virion protein.
Received December 12, 1996 Accepted March 7, 1997 相似文献
117.
S E Noble K Leyland C A Findlay C E Clark J Redfern J M Mackenzie R W Girdwood M D Donaldson 《Archives of disease in childhood》2000,82(1):27-31
OBJECTIVE: To determine the feasibility of annual hypothyroid screening of children with Down's syndrome by measuring thyroid stimulating hormone (TSH) on dried blood spots at school, and to describe the outcome in positive children. DESIGN: Establishment of a register of school children with Down's syndrome, and procedures for obtaining permission from parents, annual capillary blood samples, TSH measurement, and clinical assessment of children with TSH values > 10 mU/litre. SUBJECTS: All school age children with Down's syndrome within Lanarkshire and Glasgow Health Boards during 1996-7 and 1997-8. RESULTS: 200 of 214 school children with Down's syndrome were screened. Four of the unscreened children were receiving thyroxine treatment, and only 5 remained unscreened by default. 15 of the 200 children had capillary TSH > 10 mU/litre, and all but 1 had evidence of Hashimoto's thyroiditis. Seven of the 15 children started thyroxine treatment immediately, 6 with a pronounced rise in venous TSH and subnormal free thyroxine (fT4), and one with mildly raised TSH and normal fT4 but symptoms suggesting hypothyroidism. Eight children with mildly raised venous TSH and normal fT4 were left untreated; 1 year after testing positive, fT4 remained > 9 pmol/litre in all cases, but 4 children were started on thyroxine because of a rise in TSH. TSH fell in 3 of the 4 remaining children and there was a marginal rise in 1; all remain untreated. The prevalence of thyroid disease in this population is >/= 8.9%. CONCLUSION: Dried blood spot TSH measurement is effective for detecting hypothyroidism in Down's syndrome and capillary sampling is easily performed at school. The existing programme could be extended to the whole of Scotland within a few years. 相似文献
118.
Matthias Niedrig Katrin Leitmeyer Wilina Lim Malik Peiris John S Mackenzie Maria Zambon 《Journal of clinical virology》2005,34(1):22-25
To confirm an infection with the new coronavirus (SARS-CoV) causing the severe acute respiratory syndrome (SARS) diagnostic assays for detection of SARS-CoV specific antibody are necessary. To evaluate the diagnostic performance of laboratories an external quality assurance (EQA) study was performed in 2004. Participating laboratories (9/20) correctly detected anti-SARS antibodies in serum samples without false positive results in an immunofluorescence assay. In contrast, only 4/13 laboratories detected most of the anti-SARS antibody positive samples without false positive results using enzyme immunoassays (EIA) and/or immunoblot. The overall results clearly demonstrate that serological diagnosis of SARS-CoV remains at an early stage of development, with further technical improvements required, particularly with respect to the use of SARS specific EIAs. 相似文献
119.
120.
Ott MM Nuding SC Segers LS O'Connor R Morris KF Lindsey BG 《Journal of neurophysiology》2012,107(2):603-617
Ventrolateral respiratory column (VRC) circuits that modulate breathing in response to changes in central chemoreceptor drive are incompletely understood. We employed multielectrode arrays and spike train correlation methods to test predictions of the hypothesis that pre-B?tzinger complex (pre-B?tC) and retrotrapezoid nucleus/parafacial (RTN-pF) circuits cooperate in chemoreceptor-evoked tuning of ventral respiratory group (VRG) inspiratory neurons. Central chemoreceptors were selectively stimulated by injections of CO(2)-saturated saline into the vertebral artery in seven decerebrate, vagotomized, neuromuscularly blocked, and artificially ventilated cats. Among sampled neurons in the B?tzinger complex (B?tC)-to-VRG region, 70% (161 of 231) had a significant change in firing rate after chemoreceptor stimulation, as did 70% (101 of 144) of the RTN-pF neurons. Other responsive neurons (24 B?tC-VRG; 11 RTN-pF) had a change in the depth of respiratory modulation without a significant change in average firing rate. Seventy B?tC-VRG chemoresponsive neurons triggered 189 offset-feature correlograms (96 peaks; 93 troughs) with at least one responsive B?tC-VRG cell. Functional input from at least one RTN-pF cell could be inferred for 45 B?tC-VRG neurons (19%). Eleven RTN-pF cells were correlated with more than one B?tC-VRG target neuron, providing evidence for divergent connectivity. Thirty-seven RTN-pF neurons, 24 of which were chemoresponsive, were correlated with at least one chemoresponsive B?tC-VRG neuron. Correlation linkage maps and spike-triggered averages of phrenic nerve signals suggest transmission of chemoreceptor drive via a multipath network architecture: RTN-pF modulation of pre-B?tC-VRG rostral-to-caudal excitatory inspiratory neuron chains is tuned by feedforward and recurrent inhibition from other inspiratory neurons and from "tonic" expiratory neurons. 相似文献