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91.
92.
Existing criteria for admission of newborns to the special care nursery, Sarawak General Hospital, resulted in the admission of many neonates with certain risk factors ("at risk" neonates). To test whether such babies could be safely and better cared for in postnatal wards, 392 of these babies were randomly allocated into two groups. One group of 196 was admitted to the special care nursery and the other group of 196 was cared for with their mothers in the postnatal wards. The two groups were compared for mortality, morbidity and breastfeeding. There was no significant difference in mortality and morbidity between the two groups. While in hospital a larger proportion of babies cared for in postnatal wards were breastfed, compared to babies admitted to the special care nursery. In addition, they initiated their breastfeeding earlier. Babies with these risk factors should therefore be cared for with their mothers in the postnatal wards. 相似文献
93.
94.
Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous
enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin,
EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use
to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were
incubated at 37°C for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining
in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the
mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic
fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin,
EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the
other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation
containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for
the treatment of open wound. 相似文献
95.
环枕关节脱位:附二例报告 总被引:1,自引:0,他引:1
环枕脱位十分少见。此种病例,由于环枕部结构复杂,照片显示常不够清楚。人们往往只注住只注意环枢椎的关系而对环枕脱位的警惕性不足,容易漏诊,其后果是严重的。本文报道两例环枕关节脱位病例,并对该病的病因、发病机制、局部解剖、合并症及其诊断要点进行分析,并提出“斜坡-齿突线”对本病的诊断有重要意义。 相似文献
96.
Shang-Ying P. King Allison M. Agra Huey-Shin L. Shen Cecilia L. Chi David B. Adams Violante E. Currie Joseph R. Bertino Henry J. Pieniaszek Jr. Check Y. Quon 《Cancer chemotherapy and pharmacology》1994,35(2):101-108
The protein binding of weakly acidic and basic drugs has been shown to be altered in cancer patients. Brequinar is a weakly acidic, low-clearance, and highly protein-bound (>98% bound) antitumor agent. The pharmacokinetic parameters of brequinar are subject to large interpatient variability. This large interpatient variability may be related to brequinar's plasma protein-binding capacity (assuming no change in the intrinsic clearance of the unbound drug). The objectives of this study, therefore, were (a) to characterize brequinar's protein binding in the plasma of healthy donors and cancer patients and (b) to examine the relationships between brequinar's plasma protein binding and its pharmacokinetics in patients. Brequinar protein binding was determined in human serum albumin (HSA) solution, drug-free donor plasma, and brequinar-free, predose plasma samples obtained from a phase I cancer trial. Pharmacokinetic results from this study were used to examine relationships between plasma protein binding and drug disposition. In HSA solution and healthy donor plasma, brequinar's protein binding as determined using spiked samples was concentration-dependent. The unbound brequinar fraction increased by a factor of 3 (from 0.3% to 0.9% free) in 4% HSA solution and by a factor of 4 (from 0.4% to 1.6% free) in donor plasma as the brequinar concentrations increased from 0.1 to 2.3 mM in the HSA solution and from 0.076 to 1.5 mM in the donor plasma. Analysis of brequinar binding characteristics using the binding ratio and Rosenthal binding plots showed that albumin was the primary protein for brequinar binding in human plasma. The addition of various concentrations of 1-acid glycoprotein to 4% HSA solution did not affect the protein binding of brequinar to HSA. The protein binding determined in the plasma of cancer patients was not quantitatively different, except for variability, from that observed in the plasma of healthy donors. Examination of relationships between the unbound brequinar fraction and pharmacokinetics suggested that plasma protein binding was not a major determinant of brequinar disposition in cancer patients. 相似文献
97.
目的:探索诊断早期肝纤维化的敏感指标。方法:用放射免疫法检测236例各型肝病患者血清Ⅲ型胶原(TpyeⅢcolagen,PCⅢ)、Ⅳ型胶原(TpyeⅣcolagen,Ⅳ-C)和板层素(Laminin,LN)水平。结果:各类肝病患者血清PCⅢ、Ⅳ-C和LN水平随病情进展而逐渐升高。以PCⅢ≥135μg/L、Ⅳ-C≥130μg/L为诊断肝纤维化的临界点,其敏感度、特异性、准确率分别达80%以上。结论:表明PCⅢ、Ⅳ-C及LN可作为肝纤维化诊断较为敏感的指标,其中Ⅳ-C对早期肝纤维化的诊断优于PCⅢ及LN,对肝癌的诊断有一定意义 相似文献
98.
Xu H Lu YF Partilla JS Zheng QX Wang JB Brine GA Carroll FI Rice KC Chen KX Chi ZQ Rothman RB 《Synapse (New York, N.Y.)》1999,32(1):23-28
Previous data obtained with the cloned rat mu opioid receptor demonstrated that the "super-potent" opiates, ohmefentanyl (RTI-4614-4) and its four enantiomers, differ in binding affinity, potency, efficacy, and intrinsic efficacy. Molecular modeling (Tang et al., 1996) of fentanyl derivatives binding to the mu receptor suggests that Asp147, Tyr148, Trp318, and His319 are important residues for binding. According to this model, Asp147 interacts with the positively charged opiate agonist to form potent electrostatic and hydrogen-bonding interactions. In this study, the role of weak electrostatic and hydrogen-bonding "pi-pi" interactions of the O atom of the carbonyl group and the phenyl ring structures of RTI-4614-4 and its four enantiomers with residues Tyr148, Trp318, and His319 were explored via site-directed mutagenesis. Tyr148 (in transmembrane helix 3 {TMH3}), Trp318 (TMH7), and His319 (TMH7) were individually replaced with phenylalanine or alanine. Receptors transiently expressed in COS-7 cells were labeled with [125I]IOXY according to published procedures. Mutation of Tyr148 to phenylalanine reduced the binding affinities of some mu-selective agonists (2-7 fold) but did not alter the affinities of DAMGO, naloxone, and the non-selective opiates etorphine and buprenorphine. In contrast, this mutation significantly increased the binding affinities (decreased the Kd values) of [D-Ala2,D-Leu5]enkephalin, IOXY, and dermorphin. Mutation of Trp318 decreased opioid receptor binding to almost undetectable levels. Substitution of alanine for His319 significantly reduced binding affinities for the opioid ligands tested (1.3- to 48-fold), but did not alter the affinities of naloxone and bremazocine. These results indicate the importance of Tyrl48 and His319 for the binding of fentanyl derivatives to the mu receptor. Functional studies using the mutant receptors will provide additional insight into the mechanism of action of RTI-4614-4 and its four enantiomers. 相似文献
99.
Theoretically, Medicare provides one standard benefit package to all enrollees. But because of State-level variations in populations, service supply, and local practice patterns, national policy changes may have unequal impacts on access and service utilization. Across-the-board policy changes may create hardships in one area while appropriately discouraging use in another area. In this article, the authors describe State-level variations in Medicare enrollees, their insurance coverage, 1995 Medicare and beneficiary spending patterns in aggregate, per capita, and by service, and certain spending patterns for dually eligible beneficiaries. These data are useful for considering the State-level effects of payment reform. 相似文献
100.
硫酸二甲酯眼损伤的临床表现及治疗 总被引:1,自引:1,他引:0
对我们所遇8例硫酸二甲酯眼部中毒的临床表现及治疗进行分析讨论。眼部中毒主要为酸性烧伤、角膜损害,常同时合并呼吸道症状,重者可合并肝肾损害。治疗以硷性溶液冲洗结膜囊及局部对症为主。 相似文献