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991.
Liver injuries may be due to either blunt or penetrating trauma to the thorax or abdomen. Specific treatment depends on the site and extent of hepatic injury. Following resuscitation with intravenous fluids and blood as needed, surgical therapy is directed to provide hemostasis, remove necrotic liver tissue and promote adequate external drainage in the postoperative period. While local measures are usually sufficient, complex hepatic wounds may require extensive resection and vascular ligature or repair. 相似文献
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Synthesis of Plastoquinone Analogs and Inhibition of Photosynthetic and Mammalian Enzyme Systems 下载免费PDF全文
Jan B?ler Ronald Pardini Hanna T. Mustafa Karl Folkers Richard A. Dilley Frederick L. Crane 《Proceedings of the National Academy of Sciences of the United States of America》1972,69(12):3713-3717
New 5-hydroxy- and 5-chloro-6-alkyl-1,4-benzoquinones with one or two methyl groups on the nucleus were synthesized as potential antimetabolites of plastoquinones for biological research on photosynthetic and mammalian enzyme systems; the primary emphasis was on photosynthesis.2,3-Dimethyl-5-hydroxy-6-phytyl-1,4-benzoquinone completely inhibited in chloroplasts the water-dependent electron transport, but photosystem I was insensitive to this analog. The data are consistent with the interpretation that this analog inhibits electron transport in the chain prior to the site of electron donation from the ascorbate-dichlorophenolindophenol couple. Concentrations of 70 muM and 120 muM of this analog caused about 50 and 100% inhibition, respectively, of cyclic photophosphorylation.2,3-Dimethyl-5-hydroxy-6-phytyl-1,4-benzoquinone is a new type of inhibitor of photosynthetic electron transport that specifically inhibits the rate-limiting step between photosystems I and II. Structurally related analogs caused inhibitions in the range of 50-100% in chloroplasts.These analogs showed marginal inhibition in mitochondrial coenzyme Q(10)-oxidase systems from beef heart. 相似文献
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Mucormycosis is caused principally by members of the genus Rhizopus, especially R arrhizus and R. oryzae. Infection attributable to R. rhizopodiformis has rarely been documented. Of 13 cases of mucormycosis diagnosed during a 4-year period (1974 to 1978) at The Mount Sinai Hospital, 6 cases, occurring within 9 months, were caused by R. rhizopodiformis. The six isolates were identified mainly by: growth at 50 degrees C; production of short, sometimes branched, sporangiophores arising from opposite rhizoids; elongated columellae; and small spherical-to-elliptical, smooth-to-finely striated sporangiospores. The possibility that this explosive occurrence of R. rhizopodiformis at our institution was because of nosocomial acquisition was strongly supported by the recovery of this same mycotic agent from adhesive bandages used in the cardiac intensive care unit, where a patient developed subcutaneous R. rhizopodiformis infection after cardiac surgery. The invasive potential of R. rhizopodiformis was manifested by the extensive subcutaneous and systemic infections in each of the six patients, three of whom developed antibody against this mucormycotic agent. 相似文献
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F Santos J C Chan R J Krieg K Niimi J D Hanna M D Wellons L F Poletti 《Kidney international》1992,41(2):356-360
To examine whether growth hormone (GH) secretion is adversely affected by chronic renal insufficiency (CRI), the GH secretory response of dispersed anterior pituitary cells perifused with GH-releasing hormone (GHRH) was investigated in 5/6 nephrectomized (CRI, N = 18) and sham-operated (N = 18) rats. Two weeks after nephrectomy, during a period of stable uremia, CRI rats had significantly higher serum concentrations (mean +/- SEM) of urea nitrogen and creatinine than sham rats, 16.8 +/- 1.4 mmol/liter (47 +/- 4 mg/dl) and 79.6 +/- 0.0 mumol/liter (0.9 +/- 0.0 mg/dl) versus 6.1 +/- 0.4 mmol/liter (17 +/- 1 mg/dl) and 35.4 +/- 0.0 mumol/liter (0.4 +/- 0.0 mg/dl), respectively (P less than 0.0001). Incremental gains in body weight and nose to tail-tip length of CRI rats over two weeks were also significantly depressed, 53.3 +/- 5.38 g (CRI) versus 87.0 +/- 3.78 g (sham; P less than 0.0001) and 3.2 +/- 0.2 cm (CRI) versus 3.6 +/- 0.1 cm (sham; P less than 0.05). The cumulative food intake as well as food efficiency (g food consumed/g weight gain) were also adversely influenced by the uremic state: food intake 304 +/- 1 g (CRI) versus 397 +/- 6 g (sham; P less than 0.0001) and food efficiency 0.173 +/- 0.013 g/g of weight gain (CRI) versus 0.219 +/- 0.008 g/g of weight gain (sham). No significant difference in GH secretory rate (ng/min/10(7) cells) was found between the uremic and sham animals under basal conditions, 65.2 +/- 2.1 (CRI) and 67.9 +/- 2.2 (sham) or in response to GH-releasing hormone, 282.8 +/- 42.4 (CRI) versus 306.2 +/- 42.6 (sham).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
Jyrki T. Kuikka Hanna Mussalo Seppo Hietakorpi Esko Vanninen Esko Länsimies 《European journal of nuclear medicine and molecular imaging》1992,19(10):882-889
The detection of viable myocardium in infarcted regions, i.e. hibernating myocardium, is a major goal in clinical cardiology today. We applied combined planar and single photon emission tomography (SPET) to the non-invasive estimation of the left ventricular ejection fraction (LVEF), myocardial blood flow and free fatty acid uptake in the heart. Of the 31 patients with coronary artery disease, 25 (81%) had had a previous myocardial infarction. All patients had at least one persistent perfusion defect on the stress-rest technetium-99m hexakis-2-methoxyisobutyl isonitrile (Sestamibi) study, and the results revealed 57/124 (46%) persistent perfusion defects. As a part of the perfusion study, the LVEF was measured at rest using the first-pass 99mTc-Sestamibi injection, and the mean LVEF was 47% ±9% (mean ± 1 standard deviation). Iodine-123 phenylpentadecanoic acid (123I-pPPA) imaging at rest was performed within 2 weeks from the perfusion study. Then 6-mm transaxial, sagittal and coronal slices of the perfusion and 123I-pPPA studies were reconstructed. The bull's eye displays of the coronal slices were visually surveyed and divided into 4 quadrants: anterior, lateral, posterior and septal. The following image score was used: 0 = fixed defect, 1 = partial uptake and 2 =normal uptake. Moreover an index of metabolic reserve (MR) was calculated by dividing the bull's eye of the 123I-pPPA study by the bull's eye of resting 99mTc-Sestamibi, and its maximum value was normalized to 100%. Fourteen segments (25%) had a normal 123I-pPPA uptake with a MR value of 96% ±8%. Twenty-two segments (39%) had a partial 123I-pPPA uptake with a MR of 74% ±20%, whereas 21 segments (36%) had no 123I-pPPA uptake and a very low MR of 36%±34%. There was a highly significant correlation (r =0.70) between LVEF and MR. These findings suggest that it is possible to identify viable myocardium by measuring contractile function (first-pass, multiple-gated 99mTc-Sestamibi) and myocardial perfusion (stress-rest 99mTc-Sestamibi) and by combining these parameters with myocardial fatty acid uptake (1231-pPPA) studies.
Correspondence to: IT Kuikka 相似文献
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