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Ophira Salomon Joseph Moisseiev Tamara Vilganski Rima Dardik Shimon Kurtz Eva Shpringer David M Steinberg Nurit Rosenberg 《Blood coagulation & fibrinolysis》2006,17(6):485-488
To determine whether polymorphisms of platelet surface glycoprotein associated with arterial thrombosis are risk factors for branch retinal vein occlusion. A case-control study in which 69 patients with branch retinal vein occlusion and 147 controls who attended the eye clinic for nonvascular complications participated. DNA was extracted from whole blood and analyzed for genotyping of platelet glycoprotein polymorphisms by polymerase chain reactions and specific restricted enzymes. No relationship was found between the four platelet glycoprotein polymorphisms i.e. GPIa C807T, VNTR and Kozak of glycoprotein Ibalpha, the HPA-1 of glycoprotein IIIa and the occurrence of branch retinal vein occlusion. The HPA-2 polymorphism was found in 18 out 60 (30%) patients with branch retinal vein occlusion in comparison with 27 out 142 (19%) of controls, with an estimated odds ratio of 1.8 (95% confidence interval, 0.91-3.65). The four platelet glycoprotein polymorphisms are not risk factors for branch retinal vein occlusion and therefore it seems unnecessary to screen those patients for it. A larger study is required, however, to determine whether HPA-2 is a novel risk factor for branch retinal vein occlusion. 相似文献
3.
Pamela D Reiter Adam A Rosenberg Robert Valuck Kathryn Novak 《Journal of perinatology》2005,25(2):125-129
OBJECTIVE: To determine the effectiveness of a 10-day subcutaneous erythropoietin (rHuEpo) course of 300 units per kg per dose plus oral iron compared to oral iron alone in anemic infants during their convalescent phase of illness. STUDY DESIGN: Prospective, randomized trial performed at a 40-bed, teaching, referral, level III, neonatal intensive care unit. Infants with a gestational age at birth of less than 32 weeks, hematocrit of less than or equal to 28% with a corrected reticulocyte count of less than or equal to 5%, postconceptual age of less than 48 weeks or 5 months chronological age, and a diagnosis of anemia of prematurity were considered for inclusion. Major outcome parameters included hematocrit, corrected reticulocyte count and red cell transfusion requirements. RESULTS: A total of 60 infants were enrolled (n=30 per group). Infants randomized to rHuEpo had a significantly higher post-treatment hematocrit and corrected reticulocyte count than infants in the iron only group (p<0.001). There was a trend towards fewer red cell requirements in the rHuEpo group. CONCLUSIONS: The rHuEpo regimen studied here was associated with an acute improvement in hematocrit and corrected reticulocyte counts. This study did not demonstrate a statistically significant decrease in transfusion therapy, in part related to increased subsequent use of rHuEpo in the control group. Taken together, these data demonstrate that this regimen can effectively treat anemia in convalescent premature infants. 相似文献
4.
Use of the deoxyuridine suppression test to evaluate localized folate deficiency in rat colonic epithelium 总被引:1,自引:0,他引:1
M L Cravo J B Mason J Selhub I H Rosenberg 《The American journal of clinical nutrition》1991,53(6):1450-1454
In this study the deoxyuridine suppression test (dUST) was performed on isolated rat colonocytes to establish its value as an indicator of folate status in the colonic epithelium. [3H]thymidine incorporation into DNA was suppressed greater than 90% by deoxyuridine (dU) concentrations greater than 2.5 mumol/L. Preincubation of cells with 5-fluorouracil (1-100 mumol/L) but not methotrexate (10-100 mumol/L) resulted in a significant decrease in the degree of suppression. The dUST performed on colonocytes from folate-deficient animals displayed less suppression than on colonocytes from folate-replete animals (P less than 0.05). The abnormal degree of suppression was corrected by adding 100 mumol folinic acid/L. There was a negative correlation between the degree of suppression and the folate concentration of the colonic epithelium (P less than 0.001). These data indicate that the dUST is useful for detecting folate deficiency in the colonic epithelium and may therefore be valuable in assessing a deficiency state localized to that epithelium. 相似文献
5.
Volunteers trained by a social worker did a telephone screening of 716 elderly persons waiting for elective surgery to determine in advance of admission their need for social services. On the basis of their findings patients were given a risk rating by a social worker. While the survey was experienced positively by patients, volunteers, and social workers, the results do not establish its value in terms of shortened length of stay. Aging females living alone required the greatest amount of social work and had the longest length of stay. This group requires further study, along with the connection between intensity of illness with social problem vulnerability. The study raises other important questions critical to programming for an increasingly older population. 相似文献
6.
7.
Benign intracranial hypertension and recombinant growth hormone therapy in Australia and New Zealand
PA Crock JD McKenzie AM Nicoll NJ Howard W Cutfield LK Shield G Byrne 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):381-386
Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1 ), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1 ) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis. 相似文献
8.
M N Burnier I W McLean L E Zimmerman S H Rosenberg 《Investigative ophthalmology & visual science》1990,31(10):2037-2040
In 150 retinoblastomas the authors found a uniform thickness of the cuff of viable retinoblastoma cells that surrounds blood vessels. The mean thickness was 98.7 microns with a standard deviation of 11.9 microns. The cross-sectional area of the cuff was negatively correlated with the mitotic activity in the cuff and positively correlated with the diameter of the central vessel. The mitotic activity in the cuff of cells was inversely related to the distance from the central blood vessel. When the cuff was divided into three concentric rings, the inner ring contained a mean of 6.2 mitotic figures, the middle ring contained a mean of 2.9 mitotic figures, and the outer ring contained a mean of 0.6 mitotic figures. This pattern of growth is similar to that observed in other rapidly growing neoplasms in humans and experimental animals. In these tumors this pattern results from reduction in oxygen tension with increased distance from the central blood vessel. 相似文献
9.
Effect of dietary protein on the renin-angiotensin system in subtotally nephrectomized rats 总被引:1,自引:0,他引:1
Dietary protein restriction improves the course of renal disease in the remnant kidney model. Dietary protein restriction can also reduce plasma renin activity in several circumstances. We examined the interaction between dietary protein and the renin-angiotensin system in subtotally nephrectomized rats (1-2/3 nephrectomy). No difference was seen in tissue renin activity in rats ingesting a high (30%) versus a low (6%) protein diet. To determine the pathophysiological role of angiotensin II in subtotally nephrectomized rats, we examined the acute renal response to an intrarenal infusion of the angiotensin II antagonist Sar1 Gly8-angiotensin II (10 micrograms/kg/min). Only those subtotally nephrectomized animals ingesting a high protein diet exhibited a consistent improvement in glomerular permselectivity, as manifested by a 24% fall in the fractional clearance of albumin (basal 16.19 +/- 3.65 x 10(-4) vs. Sar1 Gly8-AII 12.26 +/- 3.21 x 10(-4); P less than 0.02) and a 19% fall in the fractional clearance of IgG (basal 3.75 +/- 0.67 x 10(-4) vs. Sar1 Gly8-AII 3.03 +/- 0.48 x 10(-4); P less than 0.02). No consistent change occurred in glomerular permselectivity in the rats on the low protein diet or rats infused with vehicle only. No change in mean arterial pressure or whole-kidney hemodynamics were seen with angiotensin II blockade. Decrements in SNGFR and glomerular capillary pressure occurred with angiotensin blockade in the animals ingesting the high protein diet, suggesting hemodynamic factors as a mechanism for the improvement in permselective defects.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.