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101.
1. The possibility that altered synthesis of vascular nitric oxide (NO) plays a role in the development of corticotropin-induced hypertension in sheep was examined by determining the effect of concomitant infusion of L-arginine, a precursor of NO, on the development of the hypertension. 2. Corticotropin (5 μg/kg per h) infused over 2 days increased mean arterial pressure (MAP) from 83 ± 4 to 99 ± 4 mmHg in five conscious sheep. Concomitant infusion of L-arginine (60 mg/kg per h) did not alter this response; infusion of L-arginine alone had no effect on blood pressure. 3. The dose of L-arginine (60 mg/kg per h) used blocked the rise in MAP (+16 mmHg) in response to a 5 h infusion of N-nitro-L-arginine (1 mg/kg per h). 4. These findings suggest that disruption of NO synthesis does not play a role in the development of corticotropin hypertension in sheep. 相似文献
102.
103.
E Cuerda Galindo JJ Goday Buján JM García Silva W Martínez M Verea Hernando E Fonseca 《Journal of the European Academy of Dermatology and Venereology》2004,18(5):586-587
The pathogenetic mechanism of fixed drug eruption (FDE) is still unknown. One of the most common causes of FDE is the use of nonsteroidal antiinflammatory drugs (NSAIDs). Oxicams are in the NSAID group and piroxicam is one of the most used of these drugs. FDE caused by piroxicam is rare but a few cases have been reported. Patch tests are useful for diagnosing some cases of FDE; they give variable results on previously affected skin while no reaction appears on unaffected skin. Some cases of cross-sensitivity among piroxicam and other substances have been reported. We report two new cases of FDE due to piroxicam with negative patch test on normal skin and positive results on affected skin. 相似文献
104.
105.
鼠尾静脉流体力学转染技术对绿色荧光蛋白表达质粒器官靶向分布的影响 总被引:1,自引:1,他引:1
目的:观察流体力学尾静脉注射对绿色荧光蛋白基因器官靶向性的影响,为今后质粒载体的基因治疗和功能研究寻找潜在的靶器官。方法:实验于2005-12/2006-04在江西省分子医学重点实验室完成。选用健康雄性昆明鼠40只,将32只小鼠按随机数字表法分为流体力学注射和常规注射两大组,每大组再分为转染组和对照组两个小组(n=8),并设正常对照组(n=8)。①流体力学转染组将100μg/只绿色荧光蛋白表达质粒溶液2mL在5s内快速注入尾静脉;对照组仅在5s内注入林格氏液2mL。②常规注射组则将2mL林格氏液或绿色荧光蛋白表达质粒溶液在30s左右注入尾静脉。注射结束后24h采集各组小鼠血清检测转氨酶,并采集肝、脾、心、肾、肺和脑组织进行冰冻切片,部分肝组织采用多聚甲醛固定后切片,荧光显微镜下观察。结果:40只小鼠全部进入结果分析,无脱失。①流体力学注射组和常规注射组小鼠血清转氨酶与正常对照组比较差异均无显著性意义(P>0.05)。②常规尾静脉注射引起少数肾小球细胞表达绿色荧光蛋白,而肝、脾、心、肺及脑等组织未见明显绿色荧光蛋白表达。③流体力学注射引起肝内绿色荧光蛋白高水平表达,肝细胞表达率接近45%,其他组织则无绿色荧光蛋白表达。结论:流体力学方法是肝靶向性的活体基因转染方法,绿色荧光蛋白可作为该方法进行目的基因研究的一个可靠和方便的示踪剂。 相似文献
106.
Richter's syndrome with different immunoglobulin light chains and different heavy chain gene rearrangements 总被引:2,自引:0,他引:2
van Dongen JJ; Hooijkaas H; Michiels JJ; Grosveld G; de Klein A; van der Kwast TH; Prins ME; Abels J; Hagemeijer A 《Blood》1984,64(2):571-575
In a patient with Richter's syndrome, the chronic lymphocytic leukemia (CLL) expressed lambda, mu, and delta immunoglobulin (lg) chains and the non-Hodgkin lymphoma (NHL) kappa, mu, and delta lg chains. The difference in lg light chain expression suggests that the CLL and NHL are independent malignancies, or that the oncogenic event occurred in a B cell differentiation stage after the heavy chain gene rearrangements but before the selection of the light chain. Analysis of DNA by Southern blotting revealed that the lg heavy chain genes of the two malignancies were rearranged in a different way. We therefore conclude that in this patient the NHL cannot be regarded as a progression of the CLL but should most likely be considered as an independent B cell malignancy, which arose in a susceptible host. 相似文献
107.
Depression and depressive symptoms in rheumatoid arthritis patients: an analysis of their occurrence and determinants 总被引:6,自引:3,他引:6
Abdel-Nasser AM; Abd El-Azim S; Taal E; El-Badawy SA; Rasker JJ; Valkenburg HA 《Rheumatology (Oxford, England)》1998,37(4):391-397
The objectives were to determine the differences in depressive symptoms and
depression between rheumatoid arthritis (RA) and osteoarthritis (OA)
patients, and to analyse the contribution of sociodemographic and clinical
variables to depression in RA patients. The responses of 60 Egyptian RA
patients and 40 patients with OA of the knees to the Symptom Checklist-90-R
Depression subscale were compared. The proportions of patients from both
groups confirmed by a psychiatric interview to be clinically depressed
according to the DSM-III-R criteria were also compared. The contributions
of sociodemographic and disease variables to depressive symptoms and
clinical depression in RA patients were explored by multiple linear and
logistic regression, respectively. RA patients showed significantly higher
depression scores than OA patients (P = 0.001). The difference was
unaffected by controlling for the effects of age, sex, disease duration and
the sociodemographic covariates. A depressive disorder was clinically
confirmed in 23% of RA patients and 10% of OA patients. The erythrocyte
sedimentation rate (ESR), being unmarried and an urban residence were
significant predictors of depressive symptoms (P < 0.05), while being
unmarried (P < 0.05, OR = 2.1) and HAQ disability (P < 0.01, OR =
3.8) were significant predictors of clinical depression in RA patients. RA
patients have significantly more depressive symptoms and tend to be more
clinically depressed than OA patients. The contribution of some
sociodemographic and clinical variables to depression in RA patients was
modest, albeit significant.
相似文献
108.
Polymorphic and monomorphic HLA-DR determinants on human hematopoietic progenitor cells 总被引:2,自引:0,他引:2
Falkenburg JH; Jansen J; van der Vaart-Duinkerken N; Veenhof WF; Blotkamp J; Goselink HM; Parlevliet J; van Rood JJ 《Blood》1984,63(5):1125-1132
The expression of monomorphic Ia-like antigens and polymorphic (allotypic) HLA-DR determinants on CFU-GM, BFU-E, CFU-E, and CFU-GEMM was studied in bone marrow and peripheral blood cells from normal healthy individuals. Using various polyclonal and monoclonal anti-Ia- like antibodies, the presence of HLA-DR backbone antigens was shown on all hematopoietic progenitor cells (HPC) studied, both in complement- dependent cytotoxicity assays and in fluorescence-activated cell sorting (FACS). The expression of allotypic determinants was demonstrated on all HPCs, using the HLA-DR typing sera anti-HLA-DR1, 2, 3, 4, 5, and 7. The Class II antigen MT-2 was also shown on all HPCs, using both monoclonal and alloantisera, whereas the MB-1 (DC-1) determinant could not be demonstrated on HPCs. This might open the possibility of removing MB-1-positive malignant cells from the graft in autologous bone marrow transplantation. 相似文献
109.
Immunologic injury to vascular endothelial cells: effects on release of prostacyclin 总被引:1,自引:0,他引:1
Prostacyclin is released from cultured and ex vivo bovine vascular endothelium following sublethal immunologic injury by a heterologous antibody to endothelial cells developed in rabbits. This release was dependent on calcium and complement and was not enhanced by the presence of platelets. Prostacyclin release was diminished 1-2 hr after the injury, but recovered fully following reculture of the endothelial cells for 72 hr. 相似文献
110.