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101.
The short term effects of a dental health educational video on adolescents' knowledge, attitude and future behaviour were assessed. Results showed a large effect on knowledge and a small effect on five attitudinal aspects. No effects were found on future behaviour. 相似文献
102.
Schröter A Zerr I Henkel K Tschampa HJ Finkenstaedt M Poser S 《Archives of neurology》2000,57(12):1751-1757
OBJECTIVE: To evaluate the diagnostic usefulness of magnetic resonance imaging (MRI) in the clinical diagnosis of Creutzfeldt-Jakob disease (CJD). BACKGROUND: Creutzfeldt-Jakob disease is a rare neurodegenerative disease that belongs to the group of human spongiform encephalopathies and usually affects elderly people. It is clinically characterized by rapidly progressive dementia and development of neurological symptoms, such as myoclonus or ataxia. Until now, neuroradiologic investigations have only played a minor role in establishing the clinical diagnosis of CJD, and they are often performed to exclude differential diagnoses. SETTING: A university hospital, base of the German National Creutzfeldt-Jakob Disease Surveillance Study. METHODS AND PATIENTS: In this study, MRIs from suspected cases of CJD were examined by one investigator blinded to the diagnosis. Patients were classified according to the established clinical and neuropathological criteria. RESULTS: Bilateral symmetric, high signal intensities on T2-weighted MRIs were present in the basal ganglia of 109 (67%) of 162 patients with CJD. In the control group, which consisted of non-CJD dementia patients, these abnormalities on T2-weighted MRIs were found in 4 (7%) of 58 patients. This corresponds to a high specificity in the differential diagnosis of CJD. CONCLUSION: These results indicate that MRI is a useful and valuable tool with reasonable sensitivity (67%) and high specificity (93%) and should be considered as an additional cornerstone in the clinical diagnosis of CJD. 相似文献
103.
104.
BACKGROUND: The excess of cardiovascular disease in end-stage renal disease (ESRD) patients is unexplained, but could relate to altered intrinsic vascular wall properties, such as increased arterial stiffness, which could be mediated by hyperhomocysteinemia. We investigated potential determinants of carotid artery stiffness in ESRD patients and the effect of long-term homocysteine-lowering treatment. PATIENTS AND METHODS: Fifty-four patients on maintenance dialysis treatment were studied at baseline. Fourty-one patients completed the treatment protocol, which consisted of a 12-week treatment with folic acid 5 mg daily with or without betaine 4 g per day, and of 1 or 5 mg of folic acid thereafter for 40 weeks. Both phases were randomized. Compliance and distensibility coefficients (CC and DC) and the stiffness index (beta) of the common carotid artery were determined at baseline and after 52 weeks of treatment using a non-invasive vessel wall movement detector system. RESULTS: At baseline, plasma total homocysteine was elevated (44.1+/-33.7 micromol/l), but showed no relationship with CC, DC or beta. Age and mean arterial pressure (MAP) were the only independent determinants of CC and DC, whereas beta was associated with age only. Plasma homocysteine showed a sustained decrease after therapy (20.7+/-9.0 micromol/l at week 52). No significant changes occurred in CC (from 0.59+/-0.21 to 0.60+/-0.22 mm2/kPa; p = 0.47), in DC (from 14.9+/-6.1 to 15.3+/-6.2 10(-3)/kPa; p = 0.55), or in beta (from 10.9+/-4.7 to 11.2+/-4.4; p = 0.64). No independent determinants were detected for the change in CC, whereas the change in DC was inversely related to the change in MAP (stand. r = -0.58; p<0.0002). The decrease in MAP after therapy was significant (p = 0.003) and was related to the dialysis mode (p = 0.003) and smoking status (p = 0.02). CONCLUSION: Folic acid treatment of hyperhomocysteinemia has no major effect on carotid artery stiffness in chronic dialysis patients. The results do, however, emphasize the importance of tight blood pressure control in these patients. 相似文献
105.
106.
A 49-year-old white female patient was referred to the ENT Department, Zentralkrankenhaus, Bremen, because of conductive hearing
loss. Widespread tumor formation was found in the left temporal bone and was identified by biopsy to be an osteoclastoma.
The tumor was extirpated surgically and reconstruction was performed. Periodic clinical follow-ups during a 36-month period
after surgery have included control computed tomographic scans and have shown no evidence for recurrent disease. The specific
pathology of the osteoclastoma is presented and different ways for treatment are discussed. 相似文献
107.
M. C. Koch K. Stegmann A. Ziegler B. Schröter A. Ermert 《European journal of pediatrics》1998,157(6):487-492
A number of recent studies have demonstrated that the occurrence and recurrence risk of neural tube defects (NTD) is reduced
by folic acid supplementation before and during pregnancy. Epidemiological studies have shown low plasma folate and raised
plasma homocysteine in women with spina bifida aperta (SB) children suggesting an abnormal folate metabolism. The 5,10-methylenetetrahydrofolate
reductase (MTHFR) variant C677T, resulting in a decreased activity of the enzyme, has been associated with the development
of NTD. Several studies demonstrated that homozygosity for the C677T mutation occurs at a higher frequency in patients with
SB phenotype than in control individuals. The SB risk is strongest if both the mother and her child have the mutation in the
homozygous state. In the present study we compared the frequency of the C- and T-alleles in healthy German individuals (n=153) with German SB patients (n=137). Our study groups reveal no significant difference in C/T-allele frequencies and genotype distributions. A family based
association study, the transmission disequilibrium test, confirms the absence of an association between T-allele and SB. In
9 of 40 families we were able to exclude linkage to the MTHFR locus (1p36.3) employing different inheritance models.
Conclusion Our data show no evidence for an association between the C677T mutation and the occurrence of the SB phenotype. Therefore
we cannot support the hypothesis that the MTHFR variant does account for a significant genetic predisposition to the SB phenotype
in the studied German patients.
Received: 11 June 1997 / Accepted in revised form: 3 November 1997 相似文献
108.
The projections to the mushroom bodies (mbs) have been clearly described in the brain of adult honeybees (Apis mellifera). Olfactory projection neurons arborize in the lip of the calyceal neuropil, whereas visual projection neurons project to the collar. To study the maturation of this pattern of innervation, as well as the development of uniglomerular projection neurons within the antennal lobes (als), we conducted the following three studies focused on the first four stages of pupal development: mass staining of olfactory projection neurons, single cell labeling of olfactory projection neurons, and simultaneous labeling of olfactory projection neurons and visual projection neurons. Examination of whole-mount preparations with the confocal laser scanning microscope revealed that the olfactory projection neurons achieved their adult arborization pattern within their main output region, the lip of the mb calyces, earlier during development (pupal stage 1) than their dendritic processes within their main input region, the al (pupal stage 2). Simultaneous labeling experiments showed further that the fiber terminals of olfactory projection neurons and visual projection neurons did not overlap but instead occupied their respective projection areas within the mb calyces as early as pupal stage 1. We conclude that selective innervation of different subregions of the calycal neuropil precedes the segregation of glomerular units within the antennal lobe neuropil, and that the Kenyon cells themselves provide a template for the innervation of olfactory and visual projection neurons. 相似文献
109.
Wolfs JF van den Ham LF ter Laak MP van der Zwan A Tulleken CA 《Acta neurochirurgica》2000,142(12):1399-1407
Summary Background. The nonocclusive Excimer laser-assisted bypass technique has been described in previous studies and proved to be a promising
bypass operation in vascular brain surgery. Little is known about the morphological regeneration process of the laser-assisted
anastomosis in time.
By way of a scanning electron microscopic study we examined the way in which the anastomosis site created by the nonocclusive
Excimer laser-assisted anastomosis technique becomes endothelialized.
Methods. In 14 rabbits the internal jugular vein was placed in a loop on the abdominal aorta. The distal anastomosis was made using
the nonocclusive Excimer laser-assisted technique. The proximal anastomosis was made either laser-assisted or conventional
end-to-side. After clipping of the aorta between the two anastomoses sites the vein served as a bypass. To evaluate the endothelialization
at the laser-assisted anastomosis site in time, a scanning electron microscopic study was performed.
Results. In the first hours after the bypass operation a new intimal surface is formed by fibrin and activated platelets. Some leukocytes
are seen during the first days. The endothelialization process of the laser-assisted anastomosis site begins one day after
the operation. The gradual endothelialization process evolved along two lines. First, endothelial cells grow from the side
of the aorta to the bypass. Second, after one day solitary (blood-borne) endothelial cells deposit on the laser edge and the
sutures, covering the platelet aggregates.
Conclusions. The endothelialization of the Excimer laser-assisted anastomosis is more or less completed 9 days after the operation. The
edge created by the laser becomes smoother after a few days and is gone for the most part after 9 days. 相似文献
110.
van Dongen EP ter Beek HT Aarts LP Schepens MA Morshuis WJ Benning FJ de Boer A Boezeman EH 《Acta anaesthesiologica Scandinavica》2000,44(7):799-803
BACKGROUND: Transcranial stimulation of the motor cortex using high-voltage electrical stimuli given in train is a method of monitoring the integrity of the motor pathways during thoracoabdominal aortic aneurysm surgery. The purpose of this study was to assess the relationship between the stimulus intensity and the corresponding amplitude of the myogenic motor evoked potential (tcMEP) in response to six-pulse transcranial electrical stimulation during two levels of low-dose propofol infusion and stable fentanyl/nitrous oxide anaesthesia. METHODS: Nine patients (37-78 yr) scheduled to undergo surgery on the thoracoabdominal aorta were studied. After achieving a stable anaesthetic state the output voltage was decreased with 50 V intervals from 350 V to 200 V during a target propofol infusion aimed at a plasma steady-state concentration of 0.7 microg x ml(-1) and increased with 50 V intervals from 200 V to 450 V during a target propofol infusion aimed at a plasma steady-state concentration of 1.4 microg x ml(-1). TcMEPs were recorded from the right tibialis anterior muscle. RESULTS: Doubling the target propofol infusion to 1.4 microg x ml(-1) resulted in a 30-50% decrease in tcMEP amplitude. The largest tcMEP amplitude using the six-pulse paradigm was found during a propofol infusion aimed at a plasma concentration of 0.7 microg x ml(-1) and demanded a stimulus output of 350 V, corresponding to a charge density of 7.5 microC x cm(-2) per phase. CONCLUSION: Doubling the target propofol infusion to 1.4 microg x ml(-1) provides less robust, but still recordable tcMEPs in response to six-pulse electrical stimulation. Safety guidelines are discussed. 相似文献