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141.
142.
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor.  相似文献   
143.
Diethyl 1-cyclopropyl-5,7,8-trifluoro-1,4-dihydro-4-oxoquinoline-3,6-dicarboxylate 4 as a key-intermediate was synthesized via the Dieckmann reaction. The reaction of 4 with nucleophiles proceeded regioselectively at C-5. Facile cyclization between the C-5 and C-6 side chains of the resulting products gave novel pyrroloquinolones 10 and 12 and pyrazoloquinolones 15. They were converted into a series of cyclic amino-substituted pyrroloquinolones 17–21 and pyrazoloquinolones 22–24, and their in vitro antibacterial activities were tested. 1H-Pyrrolo[2,3-f]quinolone 17a and 2H-pyrrolo[3,4-f]quinolone 21a exhibited a potent in vitro antibacterial activity.  相似文献   
144.
The prognostic value of prostate specific antigen was evaluated to predict disease progression after endocrine therapy in patients with prostatic cancer. A total of 73 patients was studied (6 with stage B2, 16 with stage C, 9 with stage D1 and 42 with stage D2 disease). Endocrine therapy included bilateral orchiectomy, diethylstilbestrol diphosphate and luteinizing hormone-releasing hormone analogue. Pre-treatment serum prostate specific antigen levels were determined in all patients with an enzyme immunoassay kit. During a followup of 4 to 68 months (average 24 months) clinical disease progression occurred in 24 of the 73 patients. The pre-treatment prostate specific antigen level by itself did not predict disease progression. Changes in prostate specific antigen level with treatment were correlated with the interval to disease progression in the 44 patients who had prostate specific antigen determinations at regular intervals after endocrine therapy and whose initial level was greater than 10 ng./ml. Patients who had a decrease in the prostate specific antigen levels of 80% or more within 1 month after the beginning of therapy survived significantly longer free of disease progression (p less than 0.001). Patients whose prostate specific antigen level remained elevated for more than 3 months had a high risk of disease progression within 2 years. Our study suggests that patients with the more favorable prognosis can be identified early, after 1 to 3 months of endocrine therapy, by the rapid decrease in the prostate specific antigen levels.  相似文献   
145.
P E Pepe  K L Mattox  R P Fischer  C M Matsumoto 《The Journal of trauma》1990,30(9):1125-31; discussion 1131-2
The purpose of this study was to investigate the distribution of various mechanisms of injury and the relative severity of such injury cases throughout the different geographic zones of a large urban area using a computerized emergency medical services (EMS) dispatch/patient record database. The study city (population, 2 million residents) was divided into 156 geographic grids (each 4.5 by 3 miles) and the incidence and relative severity of various injury mechanisms were determined for each zone. Results: In one year (1988), there were more than 115,000 separate EMS incidents involving more than 150,000 patients, 26,000 of whom were transported for injuries incurred in 10,064 motor vehicle accidents, 4,587 falls, 4,015 lacerations/stabwounds, 1,796 beatings, 1,270 gunshots, and 952 auto-pedestrian accidents. Analysis of the 156 zones showed a disproportionate number of EMS responses in the city center with two centralmost grids accounting for about 25% of all responses. Call volume then progressively diminished toward the periphery of the city. However, with some very minor exceptions, the relative incidence and severity of the various injury mechanisms remained proportionally uniform within each zone, regardless of geographic location. Therefore, contrary to popular notoriety, the incidence and associated severity of any given injury type generally was not necessarily predicted by any particular neighborhood predilection for it, but rather by the overall demand for EMS in that zone of the city.  相似文献   
146.
To find antiviral agents, various sulfonamidobenzophenone oximes (II) were synthesized from the appropriate m-sulfonamidobenzophenones by hydroxylamine reaction. The reaction products were generally obtained as syn/anti mixtures which were separable by fractional crystallization. The anti isomer had more potent antipoliovirus activity than the syn isomer. Various sulfonamidobenzamides (III) which were structurally related to II were synthesized by the reactions of amino-substituted benzamides with sulfuryl chloride or amines with (aminosulfonyl)benzoyl chloride. Antiviral activity was examined by the plaque-inhibition test. Compounds 5, 36, and 69 exhibited strong antipicornavirus activity. The structure-activity relationships are discussed.  相似文献   
147.
148.
A Usui  K Fujita  M Imaizumi  T Abe  K Inoue  S Matsumoto  K Kato 《Gan no rinsho》1987,33(14):1763-1770
The serum concentrations of both CK-BB and NSE in patients with various lung carcinoma have been determined by the enzyme immunoassay. Serum CK-BB levels were found to be significantly increased (less than 1.0 ng/ml) in patients with a small cell carcinoma (51 cases, 74.5%), adenocarcinoma (77 cases, 36.5%), and a squamous cell carcinoma (68 cases, 39.7%). The serum NSE levels also were increased (less than 6.0 ng/ml) in cases of small cell carcinoma (72.5%), adenocarcinoma (27.3%), and squamous cell carcinoma (26.5%). Since the serum concentrations of bos CK-BB and NSE changed in parallel with the clinical course, they may be useful biomarkers for monitoring the clinical course of patients with lung cancer, especially in cases of small cell carcinoma.  相似文献   
149.
Calcineurin (CaN) is a Ca2+- and calmodulin-dependent protein phosphatase (PP2B) that, in yeast, is an integral intermediate of a salt-stress signal transduction pathway that effects NaCl tolerance through the regulation of Na+ influx and efflux. A truncated form of the catalytic subunit and the regulatory subunit of yeast CaN were coexpressed in transgenic tobacco plants to reconstitute a constitutively activated phosphatase in vivo. Several different transgenic lines that expressed activated CaN also exhibited substantial NaCl tolerance, and this trait was linked to the genetic inheritance of the CaN transgenes. Enhanced capacity of plants expressing CaN to survive NaCl shock was similar when evaluation was conducted on seedlings in tissue culture raft vessels or plants in hydroponic culture that were transpiring actively. Root growth was less perturbed than shoot growth by NaCl in plants expressing CaN. Also, NaCl stress survival of control shoots was enhanced substantially when grafted onto roots of plants expressing CaN, further implicating a significant function of the phosphatase in the preservation of root integrity during salt shock. Together, these results indicate that in plants, like in yeast, a Ca2+- and calmodulin-dependent CaN signal pathway regulates determinants of salt tolerance required for stress adaptation. Furthermore, modulation of this pathway by expression of an activated regulatory intermediate substantially enhanced salt tolerance.  相似文献   
150.
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