全文获取类型
收费全文 | 1162篇 |
免费 | 92篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 62篇 |
妇产科学 | 15篇 |
基础医学 | 125篇 |
口腔科学 | 8篇 |
临床医学 | 240篇 |
内科学 | 186篇 |
皮肤病学 | 5篇 |
神经病学 | 140篇 |
特种医学 | 108篇 |
外国民族医学 | 1篇 |
外科学 | 156篇 |
综合类 | 31篇 |
一般理论 | 1篇 |
预防医学 | 47篇 |
眼科学 | 43篇 |
药学 | 36篇 |
中国医学 | 1篇 |
肿瘤学 | 37篇 |
出版年
2019年 | 13篇 |
2018年 | 18篇 |
2017年 | 11篇 |
2016年 | 14篇 |
2015年 | 19篇 |
2014年 | 9篇 |
2013年 | 63篇 |
2012年 | 38篇 |
2011年 | 49篇 |
2010年 | 26篇 |
2009年 | 19篇 |
2008年 | 39篇 |
2007年 | 41篇 |
2006年 | 43篇 |
2005年 | 45篇 |
2004年 | 34篇 |
2003年 | 27篇 |
2002年 | 37篇 |
2001年 | 26篇 |
2000年 | 25篇 |
1999年 | 31篇 |
1998年 | 17篇 |
1997年 | 9篇 |
1994年 | 11篇 |
1993年 | 17篇 |
1992年 | 45篇 |
1991年 | 34篇 |
1990年 | 27篇 |
1989年 | 34篇 |
1988年 | 45篇 |
1987年 | 38篇 |
1986年 | 23篇 |
1985年 | 30篇 |
1984年 | 23篇 |
1983年 | 25篇 |
1981年 | 23篇 |
1980年 | 13篇 |
1979年 | 19篇 |
1978年 | 15篇 |
1977年 | 11篇 |
1976年 | 16篇 |
1975年 | 18篇 |
1974年 | 20篇 |
1973年 | 10篇 |
1972年 | 16篇 |
1971年 | 14篇 |
1970年 | 12篇 |
1969年 | 11篇 |
1967年 | 10篇 |
1966年 | 8篇 |
排序方式: 共有1271条查询结果,搜索用时 15 毫秒
1.
2.
In a randomized, double-masked study, 41 patients with primary open-angle glaucoma or ocular hypertension were treated with betaxolol 0.5% or timolol 0.5% drops for 26 weeks. The average decrease in intraocular pressure (IOP) over the total study period was significant with both betaxolol (-6.3 mmHg) and timolol (-7.2 mmHg) in patients receiving no adjunctive therapy. There was no difference between betaxolol and timolol with respect to changes from baseline IOP. Significantly decreased mean brachial arterial pressure (MAP) was seen only with timolol, although the difference between the two groups was not significant. Pulse, pupil size, and basal tear secretion were unchanged in both groups. Burning upon instillation of the drops was more frequent with betaxolol. 相似文献
3.
L R Mandell N Wollner Z Fuks 《International journal of radiation oncology, biology, physics》1987,13(3):359-363
The records of 95 consecutive children less than or equal to 21 years of age with previously untreated diffuse histology NHL registered in our protocols from 1978 to 1983 were reviewed. Seventy-nine patients were considered eligible for analysis. The histologic subtypes represented included lymphoblastic (LB) 37%; histiocytic (DHL) 29%; undifferentiated (DU) 19%; poorly differentiated (DPDL) 9%; and unclassified (UNHL) 6%. Distribution of the patients according to stage showed Stage I, 0%; Stage II, 11%; Stage III, 53%; Stage IV, 36%. Four different Memorial Hospital protocols for systemic chemotherapy were used (LSA2L2 73%; L10 9%; L17 10%; L17M 8%); however, the IT (intrathecal) chemotherapy was uniform (Methotrexate: 6.0-6.25 mg/M2 per treatment course) and was included in the induction, consolidation, and maintenance phases of all treatment protocols. Cranial radiation was included in the induction, consolidation, and maintenance phases of all treatment protocols. Cranial radiation was not included in the CNS prophylaxis program. The overall median time of follow-up was 43 months. The overall CNS relapse rate was 6.3%, however, the incidence of CNS lymphoma presenting as the first isolated site of relapse in patients in otherwise complete remission (minimum follow-up of 19 months with 97% of patients off treatment) was only 1/58 (1.7%). Our data suggests that IT chemotherapy when given in combination with modern aggressive systemic combination chemotherapy, and without cranial radiation appears to be a highly effective modality for CNS prophylaxis regardless of stage, histology, or bone marrow or mediastinal involvement. Therefore, with the commonly used aggressive combination chemotherapy for the management of all stage diffuse pediatric NHL, and the known increased risk of leukoencephalopathy with combination of cranial radiation and intensive systemic and intrathecal chemotherapy, we believe that cranial radiation may not be indicated for CNS prophylaxis in pediatric NHL. 相似文献
4.
5.
L A Mandell M Afnan 《Clinical and investigative medicine. Médecine clinique et experimentale》1991,14(2):131-141
Our objective was to define the functional characteristics of chemotactic inhibitors in sera of patients with various neoplastic diseases. Fifty-nine patients were studied: lung cancer (15), breast cancer (11), lymphoma (20), leukemia (13). Chemotaxis and random motility were measured using a modified agarose technique with C5a and a bacterial filtrate of E. coli as the chemoattractants. Two types of inhibitors were found: chemotactic factor inhibitors and cell-directed inhibitors. The type of inhibitor as well as the specificity of the inhibitor for the chemoattractant (C5a or bacterial filtrate) varied depending upon the underlying neoplasm. Cell-directed inhibitors were reversible and none of the inhibitors affected random motility. Contrary to previous reports, the chemotactic factor inhibitors were heat-stable (p less than 0.001). Morphometric analysis of inhibited and non-inhibited cells using scanning electron photomicrographs showed a significant alteration in shape of the inhibited cells (p less than 0.003). The results indicate greater heterogeneity of the chemotactic inhibitors than was previously thought, as well as a tumour-dependent specificity of the inhibitors for the chemoattractants. 相似文献
6.
M Susan Mandell Tamara J Stoner Rebecca Barnett Abraham Shaked Mark Bellamy Gianni Biancofiore Claus Niemann Ann Walia Youri Vater Zung V Tran Igal Kam 《Liver transplantation》2007,13(11):1557-1563
Small single-institutional studies performed prior to the introduction of organ allocation using the Model for End-Stage Liver Disease (MELD) suggest that early airway extubation of liver transplant recipients is a safe practice. We designed a multicenter study to examine adverse events associated with early extubation in patients selected for liver transplantation using MELD score. A total of 7 institutions extubated all patients meeting study criteria and reported adverse events that occurred within 72 hours following surgery. Adverse events were uncommon: occurring in only 7.7% of 391 patients studied. Most adverse events were pulmonary or surgically related. Pulmonary complications were usually minor, requiring only an increase in ambient oxygen concentration. The majority of surgical adverse events required additional surgery. Analysis of a limited set of perioperative variables suggest that blood transfusions and technical factors were associated with an increased risk of adverse events. In conclusion, while early extubation appears to be safe under specified circumstances, there are performance differences between institutions that remain to be explained. 相似文献
7.
Richard D. Pearson James A. Sullivan Denise Roberts Roseann Romito Gerald L. Mandell 《Infection and immunity》1983,40(1):411-416
Leishmania donovani is an important intracellular protozoal pathogen of humans, which resides solely within mononuclear phagocytes. Phase-contrast microscopy and cinemicroscopy were used to examine the interaction of L. donovani promastigotes with human phagocytes to characterize and quantitate the sequence of events that results in leishmanial infection. 相似文献
8.
We are intrigued by the possibility of using digital spectral analysis to detect hemodialysis vascular access stenosis. Such a monitor could be inexpensive, noninvasive, and portable enough to allow continuous monitoring. This report suggests how individuals wishing to conduct such research can use a simple but effective transducer design we have employed, how the data so obtained can be analyzed in the time and frequency domains using inexpensive digital signal processing software available via the Internet, and how data recordings might be shared via the Internet to facilitate collaboration. © 2002 Biomedical Engineering Society.
PAC2002: 8763Df, 8780Tq 相似文献
9.
G W Sullivan H T Carper J A Sullivan T Murata G L Mandell 《Journal of leukocyte biology》1989,45(5):389-395
Both purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) primed neutrophils for increased superoxide production and chemiluminescence in response to f-met-leu-phe. In addition, purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) altered neutrophil shape. Recombinant interleukin-1 (alpha) used at the same concentration of interleukin-1 (beta) did not prime neutrophils for increased superoxide production after stimulation with f-met-leu-phe. Interleukin-1 expressed by monocytes in response to endotoxin stimulation could act as a modulator of neutrophil function. 相似文献
10.
The simian immunodeficiency virus (SIV) nef gene is an important determinant of viral load and acquired immunodeficiency syndrome (AIDS) in macaques. A role(s) for the HIV-1 nef gene in infection and pathogenesis was investigated by constructing recombinant viruses in which the nef gene of the pathogenic molecular clone SIVmac239 nef was replaced with either HIV-1sf2nef or HIV-1sf33nef. These chimeras, designated SHIV-2nef and SHIV-33nef, expressed HIV-1 Nef protein and replicated efficiently in cultures of rhesus macaque lymphoid cells. In two SHIV-2nef-infected juvenile rhesus macaques and in one of two SHIV-33nef-infected juvenile macaques, virus loads remained at low levels in both peripheral blood and lymph nodes in acute and chronic phases of infection (for >83 weeks). In striking contrast, the second SHIV-33nef-infected macaque showed high virus loads during the chronic stage of infection (after 24 weeks). CD4+ T-cell numbers declined dramatically in this latter animal, which developed simian AIDS (SAIDS) at 47-53 weeks after inoculation; virus was recovered at necropsy at 53 weeks and designated SHIV-33Anef. Sequence analysis of the HIV-1sf33 nef gene in SHIV-33Anef revealed four consistent amino acid changes acquired during passage in vivo. Interestingly, one of these consensus mutations generated a tyr-x-x-leu (Y-X-X-L) motif in the HIV-1sf33 Nef protein. This motif is characteristic of certain endocytic targeting sequences and also resembles a src-homology region-2 (SH-2) motif found in many cellular signaling proteins. Four additional macaques infected with SHIV-33Anef contained high virus loads, and three of these animals progressed to fatal SAIDS. Several of the consensus amino acid changes in Nef, including Y-X-X-L motif, were retained in these recipient animals exhibiting high virus load and disease. In summary, these findings indicate that the SHIV-33Anef chimera is pathogenic in rhesus macaques and that this approach, i.e., construction of chimeric viruses, will be important for analyzing the function(s) of HIV-1 nef genes in immunodeficiency in vivo, testing antiviral therapies aimed at inhibiting AIDS, and investigating adaptation of this HIV-1 accessory gene to the macaque host. 相似文献