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41.
Mesoderm induction in Xenopus laevis distinguishes between the various TGF-beta isoforms 总被引:6,自引:0,他引:6
A B Roberts P Kondaiah F Rosa S Watanabe P Good D Danielpour N S Roche M L Rebbert I B Dawid M B Sporn 《Growth factors (Chur, Switzerland)》1990,3(4):277-286
Induction of mesoderm in ectodermal explants of Xenopus laevis blastula embryos had previously been shown to respond selectively to TGF-beta 2, with TGF-beta s 1 and 5 having no activity in this assay. As TGF-beta s 1, 2, and 3 are frequently coexpressed in tissues, we wished to examine the activity of TGF-beta 3 relative to that of TGF-beta s 1 and 2 in this assay as well as in other in vitro assays. We report here that when the activity of recombinant TGF-beta 3 is normalized to that of TGF-beta 1 in the assay for growth inhibition in CCL-64 cells, it is also equal to that of TGF-beta 1 in assays for stimulation of both anchorage-independent growth of rat NRK cells and chemotaxis of human monocytes. In contrast, in the assay for mesoderm induction, recombinant TGF-beta 3 is 10-fold more active than TGF-beta 2, inducing expression of muscle specific alpha-actin at concentrations as low as 1 ng/ml. These results suggest that more complex systems, in contrast to individual cell types, may respond selectively to the various TGF-beta isoforms and that there might be biological consequences of TGF-beta isoform switching in vivo. 相似文献
42.
E De Clercq J Balzarini D Madej F Hansske M J Robins 《Journal of medicinal chemistry》1987,30(3):481-486
Treatment of 7-amino-3-beta-D-ribofuranosylpyrazolo[4,3-d]pyrimidine (formycin) with alpha-acetoxyisobutyryl bromide followed by deprotection of the resulting trans-vicinal acetoxy bromides and hydrogenolysis of the separated bromohydrins gave 2'-deoxy-(23%) and 3'-deoxyformycin (32%) after complete deprotection and purification of their hydrochloride salts. An analogous sequence gave 3'-deoxytoyocamycin and/or 3'-deoxysangivamycin in approximately 80% yields from toyocamycin. Antiviral, antineoplastic, and antimetabolic effects were evaluated for the formycin compounds and 4-amino-7-beta-D-ribofuranosylpyrrolo[2,3-d]pyrimidine (tubercidin), its 5-cyano- (toyocamycin), and 5-carbamoyl-(sangivamycin) antibiotic congeners in comparison with their 2'-deoxy, 3'-deoxy, and arabino analogues. In all cases, the modified-sugar compounds were less cytotoxic than the parent antibiotics. The majority also exhibited lower antiviral potency. However, the xylo-tubercidin analogue retained potent antiherpes 1 and 2 activity with decreased cytotoxicity. Labeled metabolite studies suggested that effects of these compounds on RNA and/or protein synthesis might be more significant than interference with DNA synthesis. 相似文献
43.
Madej A Puzianowska-Kuznicka M Tanski Z Nauman J Nauman A 《Nephron. Clinical practice》2003,93(4):e150-e157
Vitamin D co-regulates cell proliferation, differentiation and apoptosis, the processes that are disturbed in cancer tissues. It acts through the vitamin D nuclear receptor (VDR) that binds to DNA in the regulatory sequences of the target genes. As the kidney is one of the key organs for vitamin D metabolism and action, we analyzed VDR expression and its DNA binding activity in human renal clear cell cancer. 24 tumors, 24 controls that were excised from the opposite pole of the same kidney and 7 controls originating from kidneys without cancer were examined. Independently of tumor grading neither Northern blots nor immunoblotting demonstrated statistically significant differences of the mean VDR mRNA and protein amounts, respectively, in the cancer as compared to both control types. In contrast, the amount of VDR-DNA complexes was lower in 52.2% of the tumors in comparison to their corresponding controls. After normalization against VDR receptor protein amount in 34.8% of the tumors VDR-DNA binding was at least 3-4 times weaker than in the controls. However, the expression of vitamin D-dependent P21 gene on the mRNA level was not decreased in these cancers. It remains to be elucidated if altered VDR function due to its impaired binding to DNA contributes to the process of tumorigenesis, and what potential vitamin D-dependent mechanisms are involved in this process. 相似文献
44.
Dariusz Dudek Tomasz Rakowski Stanislaw Bartus Dawid Giszterowicz Wojciech Dobrowolski Krzysztof Zmudka Jaroslaw Zalewski Andrzej Ochala Pawel Wieja Bogdan Janus Artur Dziewierz Jacek Legutko Leszek Bryniarski Jacek S. Dubiel 《Journal of thrombosis and thrombolysis》2010,30(3):347-353
Early rapid platelet inhibition with abciximab before primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) is suggested as beneficial. In previous studies on early abciximab administration clopidogrel was administered in cathlab in low loading dose. We investigated the role of early abciximab administration on top of early clopidogrel 600 mg loading dose in patients with STEMI treated with PPCI. A total of 73 non-shock STEMI < 6 h patients admitted to remote hospitals with anticipated delay to PPCI < 90 min were randomly assigned to three study groups—24 pts received abciximab before transfer to cathlab (early = group EA), 27 in cathlab during PPCI (late = group LA) and in 22 abciximab administration was left to operator’s discretion during PPCI (selective = SA; given in 22.7% of patients). All patients received clopidogrel (600 mg), aspirin and heparin (70 U/kg) before transfer to cathlab. Angiography revealed more frequent infarct-related artery patency (TIMI 2 + 3: EA vs LA vs SA: 45.8 vs 18.5 vs 13.6%, P = 0.024), better myocardial tissue perfusion (MBG 2 + 3: EA vs LA vs SA: 45.8 vs 14.8 vs 13.6%, P = 0.02) in EA group in baseline angiography. There was no difference in these angiographic parameters and ECG ST-segment resolution after PPCI. In multivariate analysis early abciximab administration was an independent predictor of infarct-related artery patency in baseline angiography (OR 6.5; 95% CI 1.83–23.1; P = 0.004). Early abciximab administration before transfer for PPCI in patients with STEMI pretreated with 600 mg of clopidogrel results in more frequent infarct-related artery patency and better myocardial tissue perfusion before PPCI. 相似文献
45.
Hypolipemic agents, both statins and fibrates, may cause a spectrum of side-effects, including the transient increase in creatine phosphokinase (CPK) activity. Muscle injury may present as common myalgia, non-specific myositis with normal CPK levels, myopathy and in the most serious cases, as rhabdomyolysis. Muscle damage is much more probably in patients with concomittant kidney and liver diseases, hypothyroidism, and serious infections or after some injuries or a heavy physical effort. On the other hand, one of the most common causes of secondary hypercholesterolemia and myopathy is hypothyroidism. This condition, which may enhance the risk of muscle damage in the course of hypolipemic treatment, may sometimes present with an atypical clinical presentation, making its diagnosis challenging. In this article, we present the case of a 50-year-old male physical worker presented with marked dyslipidemia, in whom myopathy was diagnosed during therapy with hypolipemic agents. Cessation of the treatment resulted in the only moderate reduction of CPK activity. Only just the introduction of thyroid hormone supplementation led to regression of symptoms and normalization of abnormalities found in laboratory examinations including remarkable improvement in lipid profile. After several months of observation we consider that hypolipemic treatment probably revealed previously occult autoimmune thyroid disease in this patient. 相似文献
46.
Gertraut Altreuther Annette Schimmel Iris Schroeder Thomas Bach Samuel Charles Dawid J. Kok Friederike Kraemer Sonja Wolken David Young Klemens J. Krieger 《Parasitology research》2009,105(Z1):1-8
The efficacy of emodepside plus praziquantel tablets (Profender? tablets for dogs) against mature adult, immature adult and
larval stages of Toxocara canis and Toxascaris leonina was evaluated in ten randomised, blinded and placebo-controlled dose confirmation studies in naturally or experimentally
infected dogs. The tablets were used at the proposed minimum dose of 1 mg emodepside and 5 mg praziquantel per kg body weight.
Efficacy was calculated based on worm counts after necropsy. Five studies demonstrated >99% efficacy against mature adult,
>92% efficacy against immature adult, >98% efficacy against L4 and >94% efficacy against L3 larval stages of T. canis. Another five studies demonstrated >99% efficacy against mature and immature adult and >95% efficacy against L4 larval stages
of T. leonina. No side effects of the treatment were observed. Emodepside plus praziquantel tablets thus provide a comprehensive new treatment
option for ascarid infections in the dog. 相似文献
47.
Skvara H Dawid M Kleyn E Wolff B Meingassner JG Knight H Dumortier T Kopp T Fallahi N Stary G Burkhart C Grenet O Wagner J Hijazi Y Morris RE McGeown C Rordorf C Griffiths CE Stingl G Jung T 《The Journal of clinical investigation》2008,118(9):3151-3159
PKC isoforms tau, alpha, and beta play fundamental roles in the activation of T cells and other immune cell functions. Here we show that the PKC inhibitor AEB071 both abolishes the production of several cytokines by activated human T cells, keratinocytes, and macrophages in vitro and inhibits an acute allergic contact dermatitis response in rats. To translate these findings into humans, single and multiple ascending oral doses of AEB071 were administered to healthy volunteers and patients with psoriasis, respectively. AEB071 was well tolerated with no clinically relevant laboratory abnormalities. Ex vivo stimulation of lymphocytes from subjects exposed to single doses of AEB071 resulted in a dose-dependent inhibition of both lymphocyte proliferation and IL2 mRNA expression. Clinical severity of psoriasis was reduced up to 69% compared with baseline after 2 weeks of treatment, as measured by the Psoriasis Area Severity Index (PASI) score. The improvement in psoriasis patients was accompanied by histological improvement of skin lesions and may be partially explained by a substantial reduction of p40+ dermal cells, which are known to mediate psoriasis. These data suggest that AEB071 could be an effective novel treatment regimen for psoriasis and other autoimmune diseases, and that AEB071 warrants long-term studies to establish safety and efficacy. 相似文献
48.
Mortenson MM Evans DB Lee JE Hunter GJ Shellingerhout D Vu T Edeiken BS Feng L Perrier ND 《Journal of the American College of Surgeons》2008,206(5):888-895
BACKGROUND: Reoperation for hyperparathyroidism (HPT) carries an increased risk for morbidity and failure to cure. Accurate preoperative localization minimizes operative risk but is often difficult to achieve in the reoperative setting. Four-dimensional computed tomography (4D-CT) is an emerging technique that uses functional parathyroid anatomy for precise preoperative localization. We evaluated 4D-CT as a tool for localization of hyperfunctioning parathyroid tissue in the reoperative setting. STUDY DESIGN: A prospective endocrine database was queried to identify 45 patients who underwent reoperative parathyroidectomy after preoperative localization using 4D-CT. The patients were categorized into 1 of 3 groups: group 1 included those who had previous neck surgery for non-HPT conditions; group 2 included those who had undergone a previously unsuccessful neck exploration for HPT; and group 3 included patients with HPT who had a previous neck exploration with resection of at least 1 hypercellular parathyroid. RESULTS: The sensitivity of 4D-CT for localization was 88% compared with 54% for sestamibi imaging. Four-dimensional CT more often correctly localized (p=0.0003) and lateralized (p=0.005) hyperfunctional parathyroid tissue than sestamibi did. Four-dimensional CT successfully localized hyperfunctional parathyroid tissue in 18 (82%) of 22 group 1 patients, 10 (91%) of 11 group 2 patients, and 8 (67%) of 12 group 3 patients. Three patients were lost to followup. At a mean followup of 9.8 months, 39 (93%) of 42 patients were surgically cured and 3 patients (7%; 2 in group 3) had persistent HPT. CONCLUSIONS: Four-dimensional-CT is an ideal tool for preoperative localization of hyperfunctioning parathyroid tissue in the reoperative setting. Localization and successful reoperation are most difficult in patients who have undergone an earlier operation that included resection of at least one hypercellular parathyroid suggesting multigland disease. 相似文献
49.
50.
Unlabelled and radioiodinated ovine lutropin (oLH) was fractionated using reverse-phase high pressure liquid chromatography, employing a 5 micron Spherisorb C18 column. Following chromatography of unlabelled oLH at pH 3.3, 4.3 and 5.3, all eluted fractions were tested by radioimmunoassay of oLH, oLH alpha and oLH beta. Regardless of pH, the material corresponding to the first peak contained only alpha-subunit immunoreactivity. With increasing pH, the oLH alpha, oLH and oLH beta immunoreactivity separated into two groups of fractions. The retention times of the radioiodinated alpha- and beta-subunits of oLH corresponded to those of the first (descending part) and last peaks from unlabelled oLH, respectively. Following chromatography of radioiodinated oLH at pH 3.3, 5.3 and 6.5, all eluted fractions were analyzed using antiserum against either alpha- or beta-subunits of oLH. At pH 3.3 two radioactive peaks were detected: the first corresponded to the fraction with maximum binding to alpha-subunit antiserum, and the second corresponded to the fraction with maximum binding to beta-subunit antiserum. At pH 5.3 and 6.5, maximum radioactivity occurred in conjunction with maximum binding to both antisera. A free alpha-subunit in the radioiodinated oLH was even detected after chromatography at pH 6.5. 相似文献