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991.
Emilio del Rio Evaristo Sánchez Yus Pilar Simón Hugo A. Vázquez Veiga 《Journal of cutaneous pathology》1998,25(4):228-232
Two unrelated patients, a woman aged 44 and a man aged 56, with a type I neurofibromatosis, showed comedo-like formations at the top of some neurofibromas. One of them was excised in each case and they were studied histopathologically. The comedo-like formation of the first case mimicked the epithelial component of a fibrofolliculoma, and that of the second case had the structure of a primary late microcomedo and showed also anagen hair differentiation in the form of a follicular bulb and papilla. Both events are considered to be the result of a stimulation phenomenon and to reflect the essential role of the stroma in many cutaneous epithelial hyperplasias, hamartomas and possibly in some neoplasms. 相似文献
992.
W. Lane Duvall Lori B. Croft Jared S. Corriel Andrew J. Einstein Jonathan E. Fisher Pilar S. Haynes Randi K. Rose Milena J. Henzlova 《Journal of nuclear cardiology》2006,13(2):202-209
BACKGROUND: Obesity is a growing epidemic in the United States, and little is known about the characteristics of the morbidly obese population (body mass index [BMI] > or = 40 kg/m2) undergoing stress myocardial perfusion imaging (MPI). METHODS AND RESULTS: We retrospectively reviewed all consecutive morbidly obese patients without known coronary artery disease presenting for a clinically indicated technetium 99m (Tc-99m) gated stress single photon emission computed tomography imaging study over a 42-month period. Studies were analyzed for image quality, for the contribution of attenuation correction to image interpretation, and for the hemodynamic response to pharmacologic stress. In patients who subsequently had cardiac catheterization, the results were compared with those from the initial MPI study, and the Social Security Death Index and hospital medical records were searched to the assess survival rate in the entire cohort. A total of 433 patients were identified with a mean BMI of 47.3 +/- 8 kg/m2 and a mean Tc-99m stress dose of 35.6 +/- 5.4 mCi. Image quality was good in 61% of the patients, adequate in 37%, and poor in 2%. It was found to be dependent on the stressor used (better with exercise) but did not correlate with increasing weight or BMI. Attenuation correction was used in 95% of the studies reviewed and was helpful for image interpretation in 60%. The heart rate response to dipyridamole and adenosine was more pronounced and the blood pressure response to dipyridamole was less pronounced in morbidly obese patients compared with nonobese control patients. In the 43 patients who underwent catheterization, stress MPI had a sensitivity of 95% and negative predictive value of 80%. Kaplan-Meier survival analysis at 1 year showed a significant difference in survival rate of 98.3% for normal MPI studies and 94.0% for abnormal MPI studies (P = .02). CONCLUSION: Diagnostic-quality single photon emission computed tomography imaging is feasible in the majority (98%) of morbidly obese patients with the use of a dual-head camera, attenuation correction, and high stress Tc-99m tracer doses. Exercise stress was associated with better image quality. The prognostic value of a normal MPI study in this population appears to be less favorable than in non-morbidly obese patients. 相似文献
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Effects of cinacalcet on gastrointestinal hormone release in patients with secondary hyperparathyroidism undergoing dialysis. 总被引:1,自引:0,他引:1
Juan J Díez Jose Luis Miguel Rosa Codoceo Pedro Iglesias M Auxiliadora Bajo Carmen Sánchez Gloria Del Peso Fernando Gil Jorge Martinez-Ara Pilar González Gancedo Rafael Selgas 《Nephrology, dialysis, transplantation》2008,23(4):1387-1395
Objective. Our aim has been evaluating the influence of an acute dose of cinacalcet on the gastrointestinal hormonal responses to a test meal in uraemic patients with secondary hyperparathyroidism undergoing peritoneal dialysis (PD) or haemodialysis (HD). METHODS: Twenty patients (11 PD, 9 HD) on cinacalcet treatment (30-120 mg/day) were studied. Twelve patients (1 PD, 11 HD) who never received cinacalcet were studied as control group. Each patient received a test meal with blood samples at 0, 2 and 4 h. At 0 time, patients in the cinacalcet group received their usual oral dose of this calcimimetic. Plasma concentrations of intact parathyroid hormone (PTH), vasoactive intestinal peptide (VIP), ghrelin, substance P, serotonin, cholecystokinin (CCK) and gastrin were quantified at 0, 2 and 4 h. RESULTS: No significant differences in baseline concentrations of serum VIP, ghrelin, substance P, serotonine, CCK and gastrin were found between controls and cinacalcet-treated patients. In comparison with the control group, cinacalcet administration was followed by a significant decrease in VIP concentration at 4 h and a significant increase in substance P at 4 h. However, the areas under the curves of all studied gut hormones were similar in both groups. CONCLUSION: An acute dose of cinacalcet exerts minimal influence on gut hormone responses to a mixed meal in dialysis patients on chronic therapy with this drug. The small but significant differences between control subjects and patients on cinacalcet in VIP and substance P levels at 4 h should be investigated in symptomatic patients. 相似文献
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G Giussi G Ballejo E Marinho J Xercavins J Vinacur F Nieto R Roca G Rieppi 《Journal of perinatal medicine》1979,7(5):243-249
In order to find a reliable index of fetal wellbeing, maternal estriol, hCS and oxytocinase levels were related with condition of the neonate. Fifty six high risk pregnancies were studied. Estriol and hCS were determined by specific radioimmunoassay and oxytocinase with a colorimetric method. The condition of the newborn was evaluated by the APGAR score. Neonates were divided into two groups, depressed (APGAR score 0-6) and vigorous (APGAR score 7-10). When the mean birthweights of both groups were statistically different, maternal estriol levels were corrected to avoid the influencing factor of newborn weight. Mean maternal estriol level corresponding to vigorous newborns was 46.73 ng/ml. This value was statistically higher than that corresponding to the group of depressed newborns, which was 26.25 ng/ml (Fig. 1). The mean birthweight of depressed infants (2,382.75 g) was statistically lower than that of the vigorous group (3,044.75 g). The corrected mean maternal estriol values of vigorous neonates (45.44 ng/ml) was different from that of depressed ones (25.14 ng/ml) (Fig. 2). When patients were divided according to maternal diseases (diabetes, vascular pathology, Rh sensitization) serum estriol levels of the mother were statistically different according to the Apgar score of the newborns. There was no significant difference between serum hCS and oxytocinase levels of mothers with depressed and vigorous newborns. Discarding fetal weight as an influencing factor in maternal hormone level, our results indicate the suitability of maternal serum estriol determinations to predict condition of the newborns in high risk pregnancies. 相似文献
999.
Julio Martin M.D. Montserrat Garcia Anna Duran Pilar Forcada Vicente Marco 《Urologic radiology》1989,11(1):25-29
A case of leiomyosarcoma of the renal vein occurring in a 48-year-old woman is reported, and the literature is reviewed. Ultrasonography (US) revealed a rounded uniform echogenic mass in the renal hilus. Computed tomography (CT) showed a well-demarcated, uniform, soft tissue density mass. Both US and CT were useful to detect the renal mass in the present case, and may be useful for staging of renal vein leiomyosarcoma. However, these imaging procedures did not reveal diagnostic features of leiomyosarcoma. 相似文献
1000.
Selective reinnervation of two cell populations in the adult pigeon ciliary ganglion 总被引:1,自引:0,他引:1 下载免费PDF全文
1. Presynaptic fibres innervating the adult pigeon ciliary ganglion were cut 2 mm proximal to the ganglion. The modification of transmission in the ciliary and choroid cell populations was studied after periods of 6 hr-100 days.2. Transmission failed after 2 days and for the next 10 days there was no transmission through the ganglion. Long latency responses in both ciliary and choroid nerves were first observed at 13-15 days, and the latency decreased toward control values in 40 days. Electrical transmission reappeared in the ciliary population in about 26 days.3. Presynaptic fibres innervating the ciliary population have higher conduction velocities and lower electrical thresholds than those innervating the choroid group. This relation was maintained throughout the reinnervation process. Fibres innervating the extraocular muscles also regenerated and achieved conduction velocities similar to their control values.4. In two experiments out of seventeen, a few fast conducting, low threshold fibres, presumably stray ciliary fibres, innervated choroid cells and induced electrical transmission.5. It is concluded that each group of cells, ciliary and choroid, was reinnervated in a highly selective manner by its original class of presynaptic fibres, and that the presynaptic ciliary elements cause the specializations necessary for electrical transmission. 相似文献