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641.
In vitro generation of tumor-specific cytotoxic lymphocytes. Secondary allogeneic mixed tumor lymphocyte culture of normal murine spleen cells 下载免费PDF全文
In vivo or in vitro immunity to murine leukemia virus (MuLV)-induced leukemia cells which do not effectively produce virus, has been difficult to demonstrate. Because immunizations with allogeneic murine leukemia cells have been used to confer syngeneic tumor immunity to virus- producing cells, we attempted to generate lymphocytes, cytotoxic to syngeneic nonproducer leukemia cells, by stimulating normal murine spleen cells with allogeneic nonproducer leukemia cells in mixed tumor lymphocyte culture (MTLC) reactions in vitro. Secondary allogeneic MTLC of normal C57BL/6 or DBA/2 spleen cells effectively produced syngeneic tumor-specific cytotoxic lymphocytes. Target cells lysed in lymphocyte- mediated cytolysis (LMC) assays, included both Friend and Rauscher virus- induced syngeneic murine leukemia cells and chemically-induced hematopoietic tumor cells. Syngeneic tumor cells were lysed regardless of whether they produced infectious MuLV or expressed viral antigens gp-71, p-30, or p-12 at the cell surface. Syngeneic normal cells (thymus, lymph node, or Concanavalin A-stimulated spleen cells) used as targets in LMC assays were uneffected by lymphocytes harvested from secondary allogeneic MTLC. Several other in vitro culture treatments including secondary syngeneic MTLC and repetitive mixed lymphocyte culture stimulations were incapable of generating tumor-specific cytotoxic lymphocytes. Based upon these results, we propose that secondary MTLC stimulation of normal spleen cells with allogeneic nonproducer leukemia cells selects for the proliferation of two subpopulations of antigen-specific cytotoxic lymphocytes. The population capable of effecting syngeneic tumor cell lysis is directed against tumor-associated cell surface antigens which may be distinct from viral structural proteins or glycoproteins. The growth of these tumor-specific cytotoxic lymphocytes may be enhanced by a soluble allogeneic effect factor produced by the proliferation of the second subpopulation of lymphocytes generated in repetitive allogeneic MTLC, namely those lymphocytes with specificities directed against differing histocompatibility antigens. 相似文献
642.
HE Hsu CE Rydzak KL Cotich B Wang PE Sax E Losina KA Freedberg SJ Goldie Z Lu RP Walensky for the CEPAC Investigators 《HIV medicine》2011,12(2):97-108
Objectives
The aim of the study was to quantify the benefits (life expectancy gains) and risks (efavirenz‐related teratogenicity) associated with using efavirenz in HIV‐infected women of childbearing age in the USA.Methods
We used data from the Women's Interagency HIV Study in an HIV disease simulation model to estimate life expectancy in women who receive an efavirenz‐based initial antiretroviral regimen compared with those who delay efavirenz use and receive a boosted protease inhibitor‐based initial regimen. To estimate excess risk of teratogenic events with and without efavirenz exposure per 100 000 women, we incorporated literature‐based rates of pregnancy, live births, and teratogenic events into a decision analytic model. We assumed a teratogenicity risk of 2.90 events/100 live births in women exposed to efavirenz during pregnancy and 2.68/100 live births in unexposed women.Results
Survival for HIV‐infected women who received an efavirenz‐based initial antiretroviral therapy (ART) regimen was 0.89 years greater than for women receiving non‐efavirenz‐based initial therapy (28.91 vs. 28.02 years). The rate of teratogenic events was 77.26/100 000 exposed women, compared with 72.46/100 000 unexposed women. Survival estimates were sensitive to variations in treatment efficacy and AIDS‐related mortality. Estimates of excess teratogenic events were most sensitive to pregnancy rates and number of teratogenic events/100 live births in efavirenz‐exposed women.Conclusions
Use of non‐efavirenz‐based initial ART in HIV‐infected women of childbearing age may reduce life expectancy gains from antiretroviral treatment, but may also prevent teratogenic events. Decision‐making regarding efavirenz use presents a trade‐off between these two risks; this study can inform discussions between patients and health care providers. 相似文献643.
T Maddess PhD S Bedford BSc AC James PhD KA Rose PhD 《Clinical & experimental ophthalmology》1997,25(4):94-97
It has been proposed that the spatial frequency doubled (FD) illusion may originate from Y-like non-linear retinal ganglion cells. If the contrast of multi-frequency stimuli is increased, Y cells show a phase advance in the self-sum frequencies but not in other output frequencies. We looked for these effects with a multi-region pattern electroretinogram (PER.G) displaying the sum of two temporal frequencies in each visual field location. Regional variation was found in the recorded sum and difference frequencies. The results indicate that PERG signals become dominated by responses from Y-like cells when the FD illusion is seen. 相似文献
644.
Cryopreservation of single human spermatozoa 总被引:6,自引:5,他引:6
Cohen J; Garrisi GJ; Congedo-Ferrara TA; Kieck KA; Schimmel TW; Scott RT 《Human reproduction (Oxford, England)》1997,12(5):994-1001
A procedure is described that allows cryopreservation and efficient
post-thaw recovery of either a single or a small group of human
spermatozoa. This is achieved by injecting them into cell-free human, mouse
or hamster zonae pellucidae before the addition of cryoprotectant. The
method involves a combination of physical micromanipulation procedures and
glycerol-mediated cryoprotection. Zonae were tracked by positioning them in
straws between two small air bubbles prior to freezing. Spermatozoa from
poor specimens were cryopreserved and their fertilizing ability after
thawing was compared with that of fresh spermatozoa from fertile men. Human
eggs used for fertilization testing were either 1 day old or in-vitro
matured. Only 2% of the frozen zonae were lost and >75% of spermatozoa
cryopreserved in this manner were recovered and prepared for
intracytoplasmic sperm injection. The feasibility of cryopreserving a
single spermatozoon was assessed. Fifteen motile spermatozoa were frozen in
15 zonae, of which 14 were recovered after thawing. Ten were injected into
spare eggs, of which eight became fertilized. Spermatozoa recovered
mechanically from human zonae fertilized the same proportion of oocytes as
fresh fertile control spermatozoa. The recovery and fertilization rates
with spermatozoa frozen in animal zonae were 87 and 78% respectively. The
fertilization rate was marginally higher (P < 0.05) than that for
spermatozoa frozen in human zonae, perhaps because the latter may have
acrosome reacted more frequently. The zona pellucida appears to be an
ideally suited sterile vehicle for storage of single spermatozoa.
相似文献
645.
AD Luber DV Condoluci PD Slowinski M Andrews K Olson CA Peloquin KA Pappa GE Pakes 《HIV medicine》2010,11(3):193-199
Objective
An open‐label, three‐period pharmacokinetic study was conducted to investigate the drug interaction potential between fosamprenavir (FPV) and tenofovir disoproxil fumarate (TDF).Methods
Thirty‐six healthy subjects received TDF 300 mg once daily (qd) for 7 days (period 1), and then were randomized to 14 days of either FPV 1400 mg twice daily (bid) or FPV/ritonavir (RTV) 700/100 mg bid alone or with TDF (period 2). Subjects continued their randomized dose of FPV for 14 more days, adding or removing TDF based upon its receipt in period 2 (period 3). Twenty‐four‐hour pharmacokinetic sampling was carried out on day 7 of period 1 and on day 14 of periods 2 and 3. Steady‐state plasma amprenavir (APV) and tenofovir (TFV) pharmacokinetics were assessed by noncompartmental analysis and parameter values observed with each regimen were compared using geometric mean ratios with 90% confidence intervals.Results
After TDF coadministration, APV geometric mean minimum concentration (Cmin), maximum concentration (Cmax), and area under the plasma concentration–time curve (AUC) increased by 31, 3 and 7% above values observed with unboosted FPV alone; they also increased by 31, 4 and 16% above values observed with FPV/RTV alone. TFV Cmin, Cmax and AUC decreased by 12, 25 and 15% after FPV coadministration and by 9, 18 and 7% after FPV/RTV coadministration. No significant changes in RTV pharmacokinetics were observed. No differences were noted in adverse events among dosing periods.Conclusions
In this evaluation of the interaction between FPV and TDF, increases in APV exposures and modest decreases in TFV exposures were observed. These were unlikely to be clinically significant.646.
目的分析艾滋病自愿咨询检测(VCT)门诊,自愿咨询检测者的艾滋病病毒(HIV)感染状况,为西藏预防HIV传播提供科学依据。方法收集整理2003-2012年西藏某VCT门诊自愿咨询者的人口学信息及HIV抗体检测结果,用描述性方法进行统计分析。结果1929名自愿咨询检测者中,检出HIV抗体阳性188例,阳性率9.75%;女性阳性率(12.94%)高于男性(8.40%);15~44岁年龄组阳性率达9.92%,其阳性人数占所有阳性者中的94.15%(177/188)。小学及以下文化程度HIV阳性率较高,为17.92%,无业者高于其他职业;静脉注射吸毒阳性率高达62.50%。性传播占总数的89.89%。结论青壮年、小学及以下文化程度者及无业者是感染HIV的高危人群,性接触是主要的传播方式,应针对高危人群的特点,加强艾滋病的宣传教育以及行为干预工作,阻断HIV传播。 相似文献
647.
AF Goodwin S Oberoi M Landan C Charles J Groth A Martinez C Fairley LA Weiss WE Tidyman OD Klein KA Rauen 《Clinical genetics》2013,83(6):539-544
Cardio‐facio‐cutaneous syndrome (CFC) is a RASopathy that is characterized by craniofacial, dermatologic, gastrointestinal, ocular, cardiac, and neurologic anomalies. CFC is caused by activating mutations in the Ras/mitogen‐activated protein kinase (MAPK) signaling pathway that is downstream of receptor tyrosine kinase (RTK) signaling. RTK signaling is known to play a central role in craniofacial and dental development, but to date, no studies have systematically examined individuals with CFC to define key craniofacial and dental features. To fill this critical gap in our knowledge, we evaluated the craniofacial and dental phenotype of a large cohort (n = 32) of CFC individuals who attended the 2009 and 2011 CFC International Family Conferences. We quantified common craniofacial features in CFC which include macrocephaly, bitemporal narrowing, convex facial profile, and hypoplastic supraorbital ridges. In addition, there is a characteristic dental phenotype in CFC syndrome that includes malocclusion with open bite, posterior crossbite, and a high‐arched palate. This thorough evaluation of the craniofacial and dental phenotype in CFC individuals provides a step forward in our understanding of the role of RTK/MAPK signaling in human craniofacial development and will aid clinicians who treat patients with CFC. 相似文献
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为了使各种类型学生在物理学实验课程中得到有关动手能力培养、物理知识增加、思维模式转换等,本文设计了两个与医学专业有联系的新型物理学实验.通过语音和脉搏这两个与人体信息相关的物理学实验,增加学生的研究兴趣,引导学生主动思考.调查结果显示,这种类型的物理学实验得到不同专业学生的普遍认可和欢迎. 相似文献