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21.
Assay of hexosaminidase A and B enzymes in four cases with developmental regression and cherry red spot on fundus examination
confirmed that three cases had Tay-Sachs disease, and one case had Sandhoff disease. Prenatal diagnosis was carried out by
hexosaminidase enzyme assay in amniotic fluid and cells in one family, and chorionic villus sample in the second family. The
fetus was diagnosed to be unaffected in one, and affected in the other family. Assay of hexosaminidase A and B is useful for
specific diagnosis of GM2 gangliosidosis, and for prenatal diagnosis to reduce the burden of these disorders. 相似文献
22.
Increased expression of transferrin receptors and iron in amoeboid microglial cells in postnatal rats following an exposure to hypoxia 总被引:2,自引:0,他引:2
This study was aimed to ascertain the effects of hypoxia on regulation of iron in the brain of newborn rats. At 3 h and 1 day after hypoxic exposure transferrin receptor expression as detected immunohistochemically with the antibody OX-26, and the iron content as shown by Perls' staining of amoeboid microglial cells was markedly increased. The induced changes, however, were not evident at 10 min and in longer surviving rats killed at 3 and 7 days. It is suggested that the upregulation of transferrin receptor expression coupled with iron uptake by amoeboid microglial cells in the periventricular regions is a protective mechanism to facilitate the sequestration of excess iron that may have been released either from the iron-rich oligodendrocytes, or accumulated due to a disruption of its normal transportation following the hypoxic insult. This would help protect the brain from harmful effects of iron. 相似文献
23.
24.
Kamaljit Kaur Nishi Sonkhya A. S. Bapna 《Indian journal of otolaryngology and head and neck surgery》2003,55(1):21-24
Traditionally, it has been accepted that chronic suppurative Otitis media is associated with a breakdown in meekanical conduction
of sound leading to conductive hearing loss, On;the contrary, there are two schools of thought when it come, to the issue
of cpchlear involvement leading to sensorineural hearing loss (SNIIL) in chronic suppura the Otitis media. The present study
was undertaken to find out whether a sensorineural component exists in hearing loss associated with chronic suppurative otitis
media, A sample of 100 patients of unilateral chronic suppurative otitis media was selected for the Study and their bone conduction
thresholds Mere analyzed in relation to the duration of disease using audiometric data. A 24 per cent incidence of sensoineural
hearing loss was found in this series, garticularly involving the higher frequencies. Moreover, the incidence of sensorineural
hearing loss progressively increased with the increase in duration of chonic suppurative Ouns meadia 相似文献
25.
Gurmeet Kaur Dorina Belotti Angelika M Burger Kirsten Fisher-Nielson Patrizia Borsotti Elena Riccardi Jagada Thillainathan Melinda Hollingshead Edward A Sausville Raffaella Giavazzi 《Clinical cancer research》2004,10(14):4813-4821
PURPOSE: The purpose of this study was to investigate the antiangiogenic properties of 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG; NSC707545), a water-soluble benzoquinone ansamycin. EXPERIMENTAL DESIGN: The activity of 17-DMAG, in vivo, was evaluated for inhibition of fibroblast growth factor (FGF)-2-induced angiogenesis in s.c. implanted Matrigel in mice. In vitro, the activity of 17-DMAG on endothelial cells (human umbilical vein endothelial cells; HUVEC) was tested in FGF-2; and vascular endothelial growth factor (VEGF)-induced proliferation and apoptosis, motility, and extracellular matrix invasion; and on the alignment of capillary like structures in Matrigel. The protein level of heat shock protein (Hsp)90 and client proteins was examined by Western blot in FGF-2 and VEGF-stimulated HUVEC. RESULTS: Daily oral administration of 17-DMAG affected the angiogenic response in Matrigel in a dose-dependent manner. The hemoglobin content in the Matrigel implants was significantly inhibited, and the histological analysis confirmed a decrease of CD31(+) endothelial cells and of structures organized in cord and erythrocyte-containing vessels. In vitro, the compound inhibited dose-dependently the migration and the extracellular matrix-invasiveness of HUVEC and their capacity to form capillary like structures in Matrigel. 17-DMAG treatment also inhibited FGF-2 and VEGF-induced HUVEC proliferation and resulted in apoptosis. Accordingly, the expression of Hsp90 direct client proteins (pAkt and c-Raf-1) or their downstream substrates including pERK was also affected. 17-DMAG consistently increased the expression of Hsp70. Throughout the study similar results were obtained with 17-allylamino-17-demethoxygeldanamycin (17-AAG; NSC330507), the analog compound currently undergoing clinical trials. CONCLUSIONS: We show that the Hsp90 targeting agents 17-DMAG and 17-AAG inhibit angiogenesis. The strong effects on endothelial cell functions, in vitro, indicate that the antiangiogenic activity of 17-DMAG/17-AAG could also be due to a direct effect on endothelial cells. The oral bioavailability of 17-DMAG might be of advantage in investigating the potential of this compound in clinical trials with antiangiogenic as well as antiproliferative endpoints. 相似文献
26.
Marilyn A Roubidoux Judith Salmon Kaur Kent A Griffith Barbara Stillwater Paul Novotny Jeff Sloan 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1081-1086
The purpose is to determine breast cancer risk factors and correlates of mammographic parenchymal patterns among Alaska Native women. A retrospective review was performed of mammograms and mammogram records among 528 sequential screening mammogram examinations performed in Anchorage, Alaska. Mammogram density was classified by American College of Radiology (Breast Imaging Reporting and Data System) density patterns 1-4 (fat-->dense) and by percent density. Clinical data, including risk factors, ethnic group (Indian, Aleut, or Eskimo), and smoking status were obtained. Results were analyzed by univariate and multivariate analyses. Of 528 women, 164 were Indian, 155 were Aleut, and 209 were Eskimo. Mean age at first birth was lower and parity higher compared with published data in white women. Breast cancer risk factors were similar across ethnic groups. In multivariate analysis, patient age, parity, hormone replacement therapy, hysterectomy, and history of biopsy were associated, and smoking was not associated with density scores. Aleut and Indian women were less likely to have high-density mammograms than were Eskimo women (P = 0.0448). No significant differences were found between ethnic group for conventional breast cancer risk factors. Mammogram density was associated with age at screening, parity, hormone replacement therapy, hysterectomy, history of biopsy, and ethnicity but not smoking status. Eskimo women had higher mammogram density than Aleuts or Indians. 相似文献
27.
Burch PA Richardson RL Cha SS Sargent DJ Pitot HC Kaur JS Camoriano JK 《The Journal of urology》2000,164(5):1538-1542
PURPOSE: We examined the role of paclitaxel and cisplatin as first line therapy for metastatic urothelial cancer. MATERIALS AND METHODS: A total of 34 patients were enrolled in this study, and all were eligible for treatment and assessable for response. Patients received 135 mg./m.2 paclitaxel intravenously for 3 hours followed by 70 mg./m.2 cisplatin for 2 hours every 3 weeks to a maximum of 6 cycles. RESULTS: Of the patients 70% experienced a major response to treatment, which was partial/regression in 38% and complete in 32%. Toxicity was manageable with no episodes of grade 4 leukopenia or thrombocytopenia. Nonhematological toxicities included primarily nausea, anorexia and neuropathy, which rarely were severe. CONCLUSIONS: This regimen of paclitaxel and cisplatin is effective, safe and convenient to administer in an outpatient setting for advanced urothelial cancer. 相似文献
28.
Taniya Sharma Nikita Kundu Sarvpreet Kaur Amlan Chakraborty Aman Kumar Mahto Rikeshwer Prasad Dewangan Jadala Shankaraswamy Sarika Saxena 《RSC advances》2022,12(34):21760
Research in recent decades has revealed that the guanine (G)-quadruplex secondary structure in DNA modulates a variety of cellular events that are mostly related to serious diseases. Systems capable of regulating DNA G-quadruplex structures would therefore be useful for the modulation of various cellular events to produce biological effects. A high specificity for recognition of telomeric G-quadruplex has been observed for BLM helicase. We identified peptides from the HRDC domain of BLM using a molecular docking approach with various available solutions and crystal structures of human telomeres and recently created a peptide library. Herein, we tested one peptide (BLM HRDC peptide) from the library and examined its interaction with human telomeric variant-1 (HTPu-var-1) to understand the basis of G4-protein interactions. Our circular dichroism (CD) data showed that HTPu-var-1 folded into an anti-parallel G-quadruplex, and the CD intensity significantly decreased upon increasing the peptide concentration. There was a significant decrease in hypochromicity due to the formation of G-quadruplex-peptide complex at 295 nm, which indicated the unfolding of structure due to the decrease in stacking interactions. The fluorescence data showed quenching upon titrating the peptide with HTPu-var-1-G4. Electrophoretic mobility shift assay confirmed the unfolding of the G4 structure. Cell viability was significantly reduced in the presence of the BLM peptide, with IC50 values of 10.71 μM and 11.83 μM after 72 and 96 hours, respectively. These results confirmed that the selected peptide has the ability to bind to human telomeric G-quadruplex and unfold it. This is the first report in which a peptide was identified from the HRDC domain of the BLM G4-binding protein for the exploration of the G4-binding motif, which suggests a novel strategy to target G4 using natural key peptide segments.Schematic representation of (HTPu–var-1-G4) located at the 3′ end, formation of G-quadruplex, model of the G-quadruplex structure, base stacking between G-quadruplex planes, G-quadruplex structure-peptide complex and twisting of G-quadruplex planes upon peptide binding. 相似文献
29.
Pannu KK Chadha S Kumar D Preeti 《Indian journal of otolaryngology and head and neck surgery》2011,63(3):208-213
To evaluate and analyse the hearing loss in tympanic membrane perforation based on size, site and duration of perforation. The material for this study was comprised of 100 patients of either sex and of age 15?years and above selected randomly. Size of tympanic membrane perforation was assessed under microscope using calibrated wire look. Patients were divided into three groups according to size; group I (0-9?mm(2)), Group II (9-30?mm(2)), Group III (≥?30?mm(2)); according to site into anterior and posterior group; according to involvement of malleus into malleolar and non malleolar and according to duration into Group A (<1?year), Group B (1-5?years), Group C (≥?5?years). Hearing loss was measured in each case with pure tone audiometry. Data was analysed statistically using paired t-test. Hearing loss increased as the perforation size increased [I vs. II (t?-?4.23, p?0.001), II vs. III (t?-?8.19, p?0.001), I vs. III (t?-?11.68, p?0.001)]. Hearing loss was more in posterior quadrant perforation than anterior quadrant perforation but difference was not significant statistically (t?-?1.15, p?>?0.05). Hearing loss was more in malleolar perforation (t?-?5.74, p?0.001). Hearing loss increased as the duration of disease increased [A vs. B (t?-?2.01, p?0.043), A vs. C (t?-?5.49, p?0.001), B vs. C (t?-?4.14, p?0.001)]. 相似文献
30.
Ramandeep Kaur Kezia Palta Meha Bhargava Lalita Dahiya 《Expert opinion on therapeutic patents》2013,23(11):783-812
ABSTRACTIntroduction: Oxazoles are oxygen and nitrogen containing five membered heterocyclic ring systems that are present in various anticancer, antimicrobial, antihyperglycemic, anti-inflammatory agents etc. of natural origin. These pharmacologically active oxazole derivatives have attracted numerous researchers to explore this scaffold for the design and development of newer potential therapeutic agents. A large number of synthetic oxazole containing molecules have been reported over the period that exhibited wide spectrum of pharmacological profiles. Some of them have shown promising therapeutic potential and have qualified for both preclinical and clinical evaluations.Areas covered: In this review, the patents (published during 2006–2017) focusing on the biological potential of oxazoles have been covered. Therapeutic applications and various techniques/assays employed for the in vitro/in vivo evaluation of patented derivatives have been discussed majorly.Expert opinion: Chemically oxazole offers three positions for substitution. These substituted oxazole derivatives of natural as well as synthetic origin have numerous pharmacological applications including anticancer, anti-Alzheimer’s, anti-hyperglycemic, anti-inflammatory, antibacterial etc. Their pharmacological actions are mainly mediated through enzyme/receptor involved in the particular disease. The flexible nature of this ligand for various molecular level targets (enzyme/receptor) make this heterocylce an attractive scaffold for development of effective and clinically relevant oxazole containing therapeutic agents. 相似文献