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51.
Sharma Sheela Nemecz Susane K. Zhu Songyun Steele Vernon E. 《Methods in Cell Science》1997,19(1):49-52
For selection and identification of potential chemopreventive agents, a biochemical assay using induction of a phase II enzyme, glutathione-S-transferase (GST) in a liver cell culture is described. A normal human liver cell line (Chang liver cells) was selected as the candidate cell line for induction of GST (liver tissues are abundant in GST) by a known chemopreventive agent, oltipraz. Exponentially growing cells plated for 24 hours are exposed to various doses of a chemopreventive agent for an additional 24 hours, homogenized by sonication, and the homogenate is assayed for GST in a modified microplate enzyme assay using CDNB (1-chloro-2,4-dinitrobenzene) as a substrate. A concurrent protein assay is performed to determine the specific enzyme activity. As the assay is modified from a spectrophotometric assay to a microplate assay, it is reliable, sensitive and fast, a significant number of test agents can be screened in a short time. 相似文献
52.
Spear GT Kersh E Guenthner P Vishwanathan SA Gilbert D Zariffard MR Mirmonsef P Landay A Zheng L Gillevet P 《AIDS research and human retroviruses》2012,28(10):1244-1249
Abstract Vaginal bacterial communities play an important role in human health and have been shown to influence HIV infection. Pigtailed macaques (Macaca nemestrina) are used as an animal model of HIV vaginal infection of women. Since the bacterial microbiota could influence retrovirus infection of pigtailed macaques, the genital microbiota in 10 cycling macaques was determined by pyrosequencing. The microbiota of all macaques was polymicrobial with a median of 13 distinct genera. Strikingly, the genera Sneathia and Fusobacterium, both in the phylum Fusobacteria, accounted for 18.9% and 13.3% of sequences while the next most frequent were Prevotella (5.6%), Porphyromonas (4.1%), Atopobium (3.6%), and Parvimonas (2.6%). Sequences corresponding to Lactobacillus comprised only 2.2% of sequences on average and were essentially all L. amylovorus. Longitudinal sampling of the 10 macaques over an 8-week period, which spanned at least one full ovulatory cycle, showed a generally stable presence of the major types of bacteria with some exceptions. These studies show that the microbiota of the pigtailed macaques is substantially dissimilar to that found in most healthy humans, where the genital microbiota is usually dominated by Lactobacillus sp. The polymicrobial makeup of the macaque bacterial populations, the paucity of lactobacilli, and the specific types of bacteria present suggest that the pigtailed macaque microbiota could influence vaginal retrovirus infection. 相似文献
53.
Shankar EM Kumarasamy N Vignesh R Balakrishnan P Solomon SS Murugavel KG Saravanan S Velu V Farooq SM Hayath K Muthu S Solomon S Rao UA 《Japanese journal of infectious diseases》2007,60(6):337-341
The prevalence of Mycoplasma pneumoniae among HIV-positive patients with community-acquired pneumonia (CAP) remains unclear. We investigated 300 HIV-positive adults (200 with CAP and 100 with no respiratory illness) and 75 HIV-negative adults with CAP for the prevalence of respiratory pathogens using culture and serology. A growth inhibition test was employed to confirm the isolates of M. pneumoniae using species-specific typing sera. The prevalence of M. pneumoniae in HIV-positive subjects was 17% by induced sputum and 11.3% by throat swab culture. The seroprevalence of anti-M. pneumoniae IgM was 11.7% by ELISA and 14.3% by the gelatin microparticle agglutination test. The prevalence of M. pneumoniae among HIV-negative cases was relatively low. Streptococcus pneumoniae was predominant (28%) among subjects with lower respiratory disease, whereas Staphylococcus aureus (15%) was common among upper respiratory symptomatic cases. Rales (P=0.001), pharyngeal erythema (P=0.02), cervical adenopathy (P=0.004), skin rash (P=0.001), and crepitations (P=0.001) were each significantly related to M. pneumoniae positivity. Statistical significance was observed in relation to total lymphocyte count (P=0.02) and erythrocyte sedimentation rate (P=0.04), as well as M. pneumoniae positivity. This study shows that the prevalence of M. pneumoniae in HIV-positive subjects is comparatively higher than in HIV-negative subjects with pulmonary symptoms, and concords with previous pilot studies carried out in Chennai, South India. 相似文献
54.
S L Mackenzie G S Sundaram H S Sodhi 《Clinica chimica acta; international journal of clinical chemistry》1973,43(2):223-229
A technique is described for the detection of free fatty acids, triglycerides, wax esters and cholesterol esters on thin-layer Chromatographic plates. The fatty acids present in each fraction can be recovered from the plates after detection and quantitatively measured by gas-liquid chiomatography. This procedure has been sucessfully applied to the analysis of skin surface lipids. 相似文献
55.
Yu Ni Adam A. Szpiro Michael T. Young Christine T. Loftus Nicole R. Bush Kaja Z. LeWinn Sheela Sathyanarayana Daniel A. Enquobahrie Robert L. Davis Mario Kratz Annette L. Fitzpatrick Jennifer T. Sonney Frances A. Tylavsky Catherine J. Karr 《Environmental health perspectives》2021,129(4)
Background: Limited data suggest air pollution exposures may contribute to pediatric high blood pressure (HBP), a known predictor of adult cardiovascular diseases.Methods: We investigated this association in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) study, a sociodemographically diverse pregnancy cohort in the southern United States with participants enrolled from 2006 to 2011. We included 822 mother–child dyads with available address histories and a valid child blood pressure measurement at 4–6 y. Systolic (SBP) and diastolic blood pressures (DBP) were converted to age-, sex-, and height-specific percentiles for normal-weight U.S. children. HBP was classified based on SBP or DBP percentile. Nitrogen dioxide () and particulate matter in aerodynamic diameter () estimates in both pre- and postnatal windows were obtained from annual national models and spatiotemporal models, respectively. We fit multivariate Linear and Poisson regressions and explored multiplicative joint effects with maternal nutrition, child sex, and maternal race using interaction terms.Results: Mean and in the prenatal period were 10.8 [standard deviation (SD): 0.9] and 10.0 (SD: 2.4) ppb, respectively, and 9.9 (SD: 0.6) and 8.8 (SD: 1.9) ppb from birth to the 4-y-old birthday. On average, SBP percentile increased by 14.6 (95% CI: 4.6, 24.6), and DBP percentile increased by 8.7 (95% CI: 1.4, 15.9) with each increase in second-trimester . averaged over the prenatal period was only significantly associated with higher DBP percentiles [ 11.6 (95% CI: 2.9, 20.2)]. Positive associations of second-trimester with SBP and DBP percentiles were stronger in children with maternal folate concentrations in the lowest quartile ( 0.05 and 0.07, respectively) and associations with DBP percentiles were stronger in female children ( 0.05). We did not detect significant association of , road proximity, and postnatal with any outcomes.Conclusions: The findings suggest that higher prenatal exposure, particularly in the second trimester, is associated with elevated early childhood blood pressure. This adverse association could be modified by pregnancy folate concentrations. https://doi.org/10.1289/EHP7486 相似文献
56.
57.
Asif Padiyath M.D. Paul Gribben B.S. Joseph R. Abraham B.S. Ling Li M.D. Ph.D. Sheela Rangamani M.D. Andreas Schuster M.D. David A. Danford M.D. Gianni Pedrizzetti Ph.D. Shelby Kutty M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(2):203-210
We investigated intermodality agreements of strains from two‐dimensional echocardiography (2DE) and cardiac magnetic resonance (CMR) feature tracking (FT) in the assessment of right (RV) and left ventricular (LV) mechanics in tetralogy of Fallot (TOF). Patients were prospectively studied with 2DE and CMR performed contiguously. LV and RV strains were computed separately using 2DE and CMR‐FT. Segmental and global longitudinal strains (GLS) for the LV and RV were measured from four‐chamber views; LV radial (global radial strain [GRS]) and circumferential strains (GCS) measured from short‐axis views. Intermodality and interobserver agreements were examined. In 40 patients (20 TOF, mean age 23 years and 20 adult controls), LV, GCS showed narrowest intermodality limits of agreement (mean percentage error 9.5%), followed by GLS (16.4%). RV GLS had mean intermodality difference of 25.7%. GLS and GCS had acceptable interobserver agreement for the LV and RV with both 2DE and CMR‐FT, whereas GRS had high interobserver and intermodality variability. In conclusion, myocardial strains for the RV and LV derived using currently available 2DE and CMR‐FT software are subject to considerable intermodality variability. For both modalities, LV GCS, LV GLS, and RV GLS are reproducible enough to warrant further investigation of incremental clinical merit. 相似文献
58.
Bhat S Kamble RT Sundaram P Joshi JM 《The Indian journal of chest diseases & allied sciences》2002,44(3):191-194
Transdiaphragmatic extension of hydatid cyst (HC) or cystic echinococcosis (CE) of the liver is a rare phenomenon. We report a case that presented as a right middle lobe consolidation. The diagnosis of transdiaphragmatic extension of hepatic hydatid cyst was suspected on CT scan of the chest and abdomen, and confirmed operatively. A successful outcome was achieved by a combination of pre- and post-operative albendazole therapy combined with surgery. 相似文献
59.
von Eckardstein S Noe G Brache V Nieschlag E Croxatto H Alvarez F Moo-Young A Sivin I Kumar N Small M Sundaram K;International Committee for Contraception Research The Population Council 《The Journal of clinical endocrinology and metabolism》2003,88(11):5232-5239
Several preparations of testosterone and its esters are being investigated alone or in combination with other gonadotropin-suppressing agents as possible antifertility agents for men. We studied the effectiveness of 7 alpha-methyl-19-nortestosterone (MENT) as an antispermatogenic agent in men. MENT has been shown to be more potent than testosterone and to be resistant to 5 alpha-reduction. For sustained delivery of MENT, we used a system consisting of ethylene vinyl acetate implants containing MENT acetate (Ac), administered subdermally. Thirty-five normal volunteers were recruited in 3 clinics and were randomly assigned to 1 of 3 doses: 1 (12 men), 2 (11 men), or 4 (12 men) MENT Ac implants. The initial average in vitro release rate of MENT Ac from each implant was approximately 400 micro g/day. Implants were inserted subdermally in the medial aspect of the upper arm under local anesthesia. The duration of treatment was initially designed to be 6 months. However, in 2 clinics the duration of treatment was extended to 9 months for the 2-implant group and to 12 months for the 4-implant group. Dose-related increases in serum MENT levels and decreases in testosterone, LH, and FSH levels were observed. Effects on sperm counts were also dose related. None of the subjects in the 1-implant group exhibited oligozoospermia (sperm count, <3 million/ml). Four subjects in the 2-implant group became oligozoospermic, 2 of whom reached azoospermia. Eight subjects in the 4-implant group reached azoospermia, with 1 exhibiting oligozoospermia, whereas 2 were nonresponders. Side effects generally seen with androgen administration, such as increases in erythrocyte count, hematocrit, and hemoglobin and a decrease in SHBG, were also seen in this study and were reversible. Changes in lipid parameters were moderate and transient. Liver enzymes showed small changes. This study demonstrates that MENT Ac, when administered in a sustained release fashion via subdermal implants, can inhibit spermatogenesis over a prolonged period after a single administration and has the potential to be used as a male contraceptive. 相似文献
60.