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991.
V Penlap R Kieft AG McArthur W Mbacham D Mark Welch SL Hajduk VPK Titanji 《亚太热带病杂志(英文版)》2012,2(5):342-347
ObjectiveTo understand the spread of drug resistance and identifying diagnostic probes among the local tuberculosis (TB) strains in order to design rational control tools for tuberculosis controls.MethodsTA cloning and sequencing were used to characterize mutation associated with RIF resistance in 69 bp region of the gene, rpoB. The analysis identified two regions of mutations but no unusual insertion and deletion. No mutation was observed in RIF sensitive strains.ResultsWe employed Random Amplified Polymorphic DNA (RAPD) analysis for typing strains of M. tuberculosis to determine whether new strains were present among M. tuberculosis isolates circulating in Yaounde. Three groups (I to III) of M. tuberculosis were identified among 93 isolates randomly selected. RAPD analysis provided a rapid and easy means of identifying polymorphism in M. tuberculosis isolates, and it was found to be a valuable alternative epidemiological tool. RAPD was used to select the new site of diagnostic by PCR. Also single nucleotide polymorphisms between M. tuberculosis and M. bovis were found, suggesting that RAPD can be a useful technique for distinguishing between species.ConclusionsMolecular typing is defined as the integration of conventional epidemiological approach to track specific strains of pathogens in order to understand the distribution of disease in populations. 相似文献
992.
W R Gammon K B Yancey K L Mangum J D Hendrix C H Hammer 《The Journal of investigative dermatology》1989,93(2):195-200
We previously reported that complement-binding antibasement membrane zone (BMZ) autoantibodies can mediate complement-dependent directed migration and adherence of leukocytes to the BMZ in cryostat skin sections and that there is heterogeneity in the ability of anti-BMZ autoantibodies to mediate that response. Those observations suggested that directed migration and adherence of leukocytes to the BMZ might be dependent on the amount of complement-activating autoantibody deposited at the BMZ and the extent to which those antibodies could activate complement and generate C5-derived peptides (C5a, C5a des arg). In this study, we have examined the role of autoantibody concentration and C5 in mediating the adherence response. When cryostat skin sections were pretreated with anti-BMZ autoantibodies and subsequently incubated with neutrophils suspended in fresh serum, neutrophils adhered to the BMZ. Adherence was anti-BMZ autoantibody specific and proportional to anti-BMZ autoantibody concentration. To determine the role of C5 in mediating adherence, neutrophils were suspended in increasing concentrations of: 1) fresh serum, 2) heat-inactivated serum, 3) serum pretreated with antihuman C5, 4) serum pretreated with antihuman IgG, 5) C5-depleted serum, 6) purified C5, and 7) C5-depleted serum reconstituted with increasing concentrations of purified C5. The suspensions were then incubated with autoantibody-treated skin sections. The results showed a dose-dependent requirement for fresh serum and for C5-depleted serum reconstituted with increasing doses of C5. Adherence could be detected with C5 concentrations less than 200 ng/ml, which correspond to a C5a/C5a des arg concentration of 10(-8)-10(-9) molar. These results suggest that complement-dependent neutrophil adherence is a highly sensitive method for detecting and quantitating the ability of tissue-deposited anti-BMZ autoantibodies to activate complement and generate C5-derived bioactive peptides, for estimating the amount of C-activating anti-BMZ autoantibody deposited at the BMZ in vivo, and for evaluating the potential role of C-activating anti-BMZ autoantibodies in the pathogenesis of lesions. 相似文献
993.
Gao SL Mou BY Dai DS Han L Zhao SB Xu CS Xu X Cai JZ 《Hepatobiliary & pancreatic diseases international : HBPD INT》2023,22(3):239-244
Background: The effectiveness and safety of marginal donor livers remain controversial. This study aimed to investigate the clinical efficacy of marginal donor livers in patients with liver transplantation (LT).
Methods: This study included 199 liver donors (including 16 split donors) and 206 liver recipients from January 1, 2018 to January 27, 2020, with case follow-up until July 31, 2021. Clinical data of donors and recipients were retrospectively analyzed and were divided into the marginal donor and standard donor groups according to the criteria of marginal donor livers. Indices of liver and kidney functions, complications, and survival curves of the two groups were compared.
Results: Compared with the standard donor group, the blood creatinine levels were significantly higher in the marginal donor group in the first week after operation ( P < 0.05); there were no significant differences in alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels after LT (all P > 0.05); there was no significant difference in the incidence of complications after LT ( P > 0.05); there was also no significant difference in the survival curve ( P = 0.335).
Conclusions: There were no significant differences in liver and kidney function and survival curve between the standard donor and marginal donor groups. The marginal donor liver appears safe and reliable for LT and may be an important strategy to expand the donor pool and solve the shortage of organs. 相似文献
994.
995.
Kelly MP; Corson SL; Gocial B; Batzer FR; Gutmann JN 《Human reproduction (Oxford, England)》1997,12(12):2682-2686
The use of cryopreserved donor spermatozoa for insemination has become
necessary to decrease the risk from sexually transmitted infectious
diseases. Lower fecundity rates have been reported with this practice.
Efforts have been applied to increase success, including identification of
those sperm characteristics which correlate with increased fecundity. Data
from in-vitro fertilization have revealed sperm morphology, motility and
zona pellucida binding as important sperm parameters. Discontinuous Percoll
gradient preparation yields a high concentration of motile spermatozoa.
Using this preparation for thawed donor spermatozoa, we have identified
post-preparation motility and progression as factors associated with
increased fecundity. Consideration should be given to screening sperm
donors with a freeze- thaw Percoll gradient preparation prior to acceptance
into a donor bank.
相似文献
996.
间三氟甲基苯胺的合成 总被引:1,自引:0,他引:1
以三氟甲苛来起始原料,经混酸硝化和加氢还原反应合成间三氟甲基苯胺,总收率达83%,产品纯度98%以上。 相似文献
997.
998.
999.
S. W. Hendrix K. H. Miller T. E. Youket R. Adam R. J. O''Connor J. G. Morel B. E. Tepper 《Skin research and technology》2007,13(3):330-342
BACKGROUND/PURPOSE: This work was performed to optimize extraction conditions for D-Squame tape skin samples for use in the skin multiple analyte profile (SkinMAP) method, a Linco Research Corporation bead-based assay for skin analytes. The experiments were designed to help identify sources of variability during extraction that may be amenable to further control. METHODS: Two experimental designs were used to study factors influencing the extraction of skin samples from D-Squame tapes. Visually healthy skin samples were obtained from both female and male adult volar forearms. Factors studied in two experiments included: four surfactant (SDS) levels (0.02-0.2%), two buffer types [Citrate-phosphate buffered saline at pH 5.5, phosphate-buffered saline (PBS) at pH 7.4], two buffer volumes (1.0, 1.5 mL), two propylene glycol (PG) levels (0.1%, 1.0%), two extraction temperatures (7-10 degrees C, 22-30+ degrees C), two extraction times (30, 60 min), and location in sonication bath (two vectors). The response biomarkers were cortisol, fibronectin, human serum albumin, involucrin, keratin-6 and keratins 1, 10. Skin sampling sites were also evaluated as sources of variation. RESULTS: There was no single set of extraction conditions in our experiments that maximized recovery of all the biomarkers. SDS level had the most consistently significant (P<0.05) and directional effects on biomarker recoveries. In general, higher SDS resulted in higher recovery of all biomarkers. There was less consistency and fewer significant results for the other extraction factors. CONCLUSIONS: These data enable us to better manage SkinMAP studies and interpret their results. The use of 1.5 mL PBS containing 0.2% SDS and 0.5% PG with 30 min sonication at low (near 4 degrees C) temperature is optimal for the quantitation of a range of SkinMAP analytes. In order to protect researchers from obtaining inflated false positive rates, it is crucial to design such studies and analyze the data using appropriate statistical methodology, especially for those studies involving only a small number of subjects. 相似文献
1000.