全文获取类型
收费全文 | 40897篇 |
免费 | 3678篇 |
国内免费 | 155篇 |
专业分类
耳鼻咽喉 | 370篇 |
儿科学 | 1233篇 |
妇产科学 | 741篇 |
基础医学 | 5794篇 |
口腔科学 | 471篇 |
临床医学 | 4859篇 |
内科学 | 9326篇 |
皮肤病学 | 889篇 |
神经病学 | 4111篇 |
特种医学 | 1413篇 |
外国民族医学 | 1篇 |
外科学 | 5979篇 |
综合类 | 258篇 |
一般理论 | 30篇 |
预防医学 | 3233篇 |
眼科学 | 555篇 |
药学 | 2551篇 |
中国医学 | 84篇 |
肿瘤学 | 2832篇 |
出版年
2023年 | 168篇 |
2022年 | 332篇 |
2021年 | 818篇 |
2020年 | 598篇 |
2019年 | 1090篇 |
2018年 | 1237篇 |
2017年 | 972篇 |
2016年 | 997篇 |
2015年 | 1242篇 |
2014年 | 1571篇 |
2013年 | 2158篇 |
2012年 | 2816篇 |
2011年 | 3010篇 |
2010年 | 1837篇 |
2009年 | 1649篇 |
2008年 | 2542篇 |
2007年 | 2593篇 |
2006年 | 2562篇 |
2005年 | 2574篇 |
2004年 | 2467篇 |
2003年 | 2435篇 |
2002年 | 2433篇 |
2001年 | 374篇 |
2000年 | 298篇 |
1999年 | 391篇 |
1998年 | 478篇 |
1997年 | 424篇 |
1996年 | 329篇 |
1995年 | 357篇 |
1994年 | 304篇 |
1993年 | 283篇 |
1992年 | 203篇 |
1991年 | 208篇 |
1990年 | 181篇 |
1989年 | 153篇 |
1988年 | 163篇 |
1987年 | 165篇 |
1986年 | 153篇 |
1985年 | 151篇 |
1984年 | 158篇 |
1983年 | 126篇 |
1982年 | 180篇 |
1981年 | 175篇 |
1980年 | 156篇 |
1979年 | 99篇 |
1978年 | 107篇 |
1977年 | 95篇 |
1976年 | 75篇 |
1975年 | 66篇 |
1972年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Neurotropic melanoma has generally been described in the context of desmoplastic melanoma. The vast majority of melanomas displaying neurotropism contain relatively little or no melanin. Herein, we report an unusual case of neurotropic melanoma with prominent melanin content. The patient developed a tumor notable For pagetoid (superficial spreading) melanoma with partial regression and a deep component characterized by perineurial aggregates of melanophages and intraneural infiltration by melanoma cells. This case serves to alert dermatopathologists to the fact that the spectrum of neurotropic melanoma includes tumors with perineurial aggregates of pigment-containing cells. 相似文献
52.
Pushparany Chanmugathas Jean -Marc Bollag 《Archives of environmental contamination and toxicology》1988,17(2):229-237
An acid sandy loam soil was used in a column study to determine the effect of microorganisms on Cd mobilization in soil and its speciation in column leachates. Non-sterile and sterile (gamma-irradiated) soil columns were initially treated with 90 mg of Cd (NO3)2, and approximately 20 mg of added Cd was retained in the soil. Soil columns were subsequently eluted with a sterile nutrient medium for a period of up to 38 days. Non-sterile and sterile soil columns leached with sterile deionized water served as unsupplemented controls. During a leaching period of 38 days, about 36% of the sorbed Cd in soil was mobilized in the presence of microorganisms and nutrients, while less than 16% of the Cd was released from the sterile and unsupplemented soil controls. To characterize the chemical form of the microbially mobilized Cd, the leachates were analyzed by gel filtration chromatography. In this study, 86% to 93% of the mobilized Cd was associated with the low molecular weight inorganic and organic fraction, while the remainder was eluted in the high molecular weight range. The low molecular weight Cd fractions were further examined by solid phase extraction (C18 Sep-Pak), and cation-exchange chromatography. From the various analyses, it was concluded that a significant amount of Cd existed as a hydrophilic organic complex, and the remainder as cationic Cd. Soil microorganisms were mostly responsible for the transformation of Cd in soil and its subsequent mobilization. 相似文献
53.
P. E. Wallemacq Raymond Reding Etienne M. Sokal Jean Ville de Goyet Stéphane Clement de Clety Véronique Van Leeuw Marc De Backer Jean-Bernard Otte 《Transplant international》1997,10(6):466-470
Pediatric liver transplant recipients constitute a population characterized by a particularly unpredictable and poor bioavailability
of cyclosporin (CyA). Even though several adult studies show that the new oral formulation of CyA, Neoral (NEO), produces
better bioavailability and blood level predictability, few data describe its pharmacokinetics in children. We performed a
complete analysis of the pharmacokinetics of NEO in ten small children after primary liver transplantation. Three pharmacokinetic
profiles were set up with data obtained from tests taken during i. v. administration of CyA, after the first oral NEO dose,
and after the last NEO dose before discharge from the hospital. The mean half-lives obtained were 8.1, 7.7, and 6.9 h, respectively,
and the bioavailabilities were 22 % and 21 % for the first and last NEO doses. A large interpatient variability was observed.
This was due, in part, to episodes of diarrhea that interfered with the pharmacokinetic evaluation and, in part, to the variability
of post-transplant hepatic function. There was a good correlation between CyA trough levels and their related AUCs for both
NEO profiles (r = 0.93 and r = 0.74, respectively). We conclude that, even though the pediatric OLT population remains more unpredictable than that of
adults, NEO has a relatively rapid half-life and a remarkably improved bioavailability.
Received: 29 November 1996 Received after revision: 10 April 1997 Accepted: 15 May 1997 相似文献
54.
Joyce J. Fitzpatrick Sheila Ryan DeWitt Baldwin Roger Bulger Jean Johnson-Pawlson Christopher McLaughlin Maureen Kelley Leopold Selketr Bernardine Lacey Charlene Hanson Robin Harvan Patricia Hinton Walker David Sluyter Mary Joan Ladden Neal Vanselow 《Journal of Midwifery & Women's Health》1998,43(1):61-65
In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible. 相似文献
55.
G. Lallement Didier Clarençon Catherine Masqueliez Dominique Baubichon Monique Galonnier Marie-France Burckhart Michel Peoc’h Jean Claude Mestries 《Archives of toxicology》1997,72(2):84-92
Organophosphorus nerve agents are still in use today in warfare and as terrorism compounds. Classical emergency treatment
of organophosphate poisoning includes the combined administration of a cholinesterase reactivator (an oxime), a muscarinic
cholinergic receptor antagonist (atropine) and a benzodiazepine anticonvulsant (diazepam). However, recent experiments with
primates have demonstrated that such treatment, even when administered immediately after organophosphate exposure, does not
rapidly restore normal electroencephalographic (EEG) activity and fails to totally prevent neuronal brain damage. The objective
of this study was to evaluate, in a realistic setting, the therapeutic benefit of administration of GK-11 (gacyclidine), an
antiglutamatergic compound, as a complement to the available emergency therapy against organophosphate poisoning. GK-11 was
injected at a dose of 0.1 mg/kg (i.v) after a 45-min latency period to heavily intoxicated (8 LD50) primates. Just after intoxication, man-equivalent doses of one autoinjector containing atropine/pralidoxime/diazepam were
administered. The effects of GK-11 were examined on survival, EEG activity, signs of toxicity, recovery after challenge and
central nervous system histology. The present data demonstrate that treatment with GK-11 prevents the mortality observed after
early administration of classical emergency medication alone. EEG recordings and clinical observations also revealed that
GK-11 prevented soman-induced seizures and motor convulsions. EEG analysis within the classical frequency bands (beta, theta,
alpha, delta) demonstrated that central activity was totally restored to normal after GK-11 treatment, but remained profoundly
altered in animals receiving atropine/pralidoxime/diazepam alone. GK-11 also markedly accelerated clinical recovery of soman-challenged
primates. Lastly, this drug totally prevented the neuropathology observed 3 weeks after soman exposure in animals treated
with classical emergency treatment alone. GK-11 represents a promising adjuvant therapy to the currently available emergency
polymedication to ensure optimal management of organophosphate poisoning in man. This drug is presently being evaluated in
a human clinical trial for a different neuroprotective indication.
Received: 16 June 1997 / Accepted: 23 September 1997 相似文献
56.
Yawata Ayumi; Kanzaki Akio; Gilsanz Florinda; Delaunay Jean; Yawata Yoshihito 《Blood》1997,90(6):2471-2481
57.
Gail Pairitz Jarvik Terri H. Beaty Paul R. Gallagher Paul M. Coates Jean A. Cortner 《Genetic epidemiology》1993,10(4):257-270
A sample enriched for familial combined hyperlipidemia (FCHL) was examined for evidence of an association between genotype at an apolipoprotein B (apoB) elevating locus defined by complex segregation analysis and FCHL. Complex segregation analysis detected a locus with a large effect on plasma apoB levels and was used to compute the most probable genotype of family members. None of the 35 normolipidemic adults carried a copy of the allele associated with elevated apoB levels, yet 58% of the 109 adults with FCHL carried 1 (29%) or 2 (28%) copies. Two of 28 (7%) normal children had 1 copy of this allele and none had 2 copies, while 88 of 182 (48%) children with FCHL had 1 (26%) or 2 (22%) copies. Further, 4l of 48 (85%) individuals classified as having hyperapobetalipoproteinemia did not carry a copy of this “elevated apoB” allele. Therefore, the presence of the allele associated with elevation of apoB level is highly predictive of FCHL and this association cannot be explained solely by the presence of elevated apoB levels in FCHL, suggesting that the locus controlling apoB levels may play an etiologic role in FCHL. © 1993 Wiley-Liss, Inc. 相似文献
58.
Jean Addington Chrystal Mansley Donald Addington 《Revue canadienne de psychiatrie》2003,48(4):272-276
OBJECTIVE: To examine the extent of weight gain in the first year of treatment in an early psychosis program. METHOD: Subjects were 114 individuals who had experienced a first episode of psychosis and had completed 1 year in a comprehensive first-episode program. Weight and body mass index were calculated on entry to the program and at 6 and 12 months. Most of the subjects were all being prescribed second-generation antipsychotics. RESULTS: Significant increases in mean weight were observed in these young individuals over the course of the first year of treatment. CONCLUSIONS: If we are to work toward optimum treatment for first-episode subjects then potential weight gain needs to be addressed at the beginning of treatment and monitored during treatment. 相似文献
59.
Hsiu Hui Chiu Hsiao Hui Chou Wen Dar Jean Wung Yang Shieh 《Journal of microbiology, immunology, and infection》2007,40(1):14-23
BACKGROUND AND PURPOSE: Marine luminous bacteria were isolated and identified from samples in shallow coastal waters of Taiwan during the relatively warm seasons. METHODS: Identification of the luminous isolates was performed based on differences of phenotypic and genotypic characteristics together with data from phylogenetic analysis. RESULTS: Twenty seven strains of marine luminous bacteria were isolated. They were divided into five types based on differences of phenotypic characteristics. However, they could be clustered into only two genotypes according to the analysis of restriction patterns of polymerase chain reaction-amplified 16S rRNA genes digested with various restriction enzymes. The characterization data together with the 16S rRNA gene-based phylogenetic analysis revealed that the isolates included in phenotype I (seven isolates) could be Photobacterium leiognathi, and those included in phenotypes II-V (twenty isolates) might be classified as Vibrio harveyi. However, phylogeny based on gyrB sequences indicated that phenotypes II-V could be classified into two species, V. harveyi and Vibrio campbellii. CONCLUSION: Culturable luminous bacteria in the shallow coastal waters of Taiwan during the sampling period are dominated by V. harveyi/campbellii and P. leiognathi, and the former species appeared to be more prevalent and numerous than the latter species in general. 相似文献
60.
Dany Anglicheau Alexandre Lautrette Catherine Scieux Martin Flamant Frédéric Morinet Christophe Legendre 《Nephrology, dialysis, transplantation》2003,18(8):1654-1656
BACKGROUND: Routine cytomegalovirus (CMV)-pp65 antigenaemia monitoring shows that some patients will develop pp65 antigenaemia during valaciclovir prophylaxis or after cessation of treatment. The aim of this pilot study was to evaluate the safety and efficacy of lowering immunosuppression in kidney transplant recipients who exhibit mildly symptomatic CMV infections while on valaciclovir prophylaxis. METHODS: We selected 12 patients who experienced mildly symptomatic CMV infections defined as a positive CMV-pp65 antigenaemia test associated with either neutropenia, asthenia or arthralgia, but no fever. All of them received prophylaxis with valaciclovir for at least 3 months. Testing for CMV-pp65 antigenaemia was performed weekly for 6 months. RESULTS: The mildly symptomatic infections occurred at a median interval of 69 days after transplantation-during prophylaxis in eight cases and after valaciclovir discontinuation in the other four cases. All of them were effectively managed by lowering immunosuppressive therapy, leading to the disappearance of symptoms and CMV antigenaemia reduction. No immunological complication or recurrence of CMV infection or disease was noted. I.v. ganciclovir never became necessary. CONCLUSION: The mildly symptomatic CMV infections occurring in valaciclovir-treated patients may be managed efficiently and without immunologic complication by lowering immunosuppressive therapy. 相似文献