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31.
David B. Sanford M. D. Anita Yeomans-Kinney R. N. Peter W. McLaughlin M. D. Gabriel N. Hortobagyi M. D. Kapil Dhingra M. D. 《The breast journal》1996,2(5):312-319
Abstract: We performed a retrospective analysis of clinical course of 91 patients who developed both breast cancer and a chronic lymphoproliferative neoplasm and were seen at the M. D. Anderson Cancer Center between January 1, 1970 and December 30, 1991. The sample included 24 individuals who developed lymphoproliferative neoplasm first (Group A), 22 individuals with concurrent diagnosis of both malignancies (Group B), and 45 individuals who developed breast cancer first (Group C). The median time to diagnosis of secondary breast cancer and lymphoproliferative neoplasm was 66 months (range, 7–459) and 65 months (range, 0–334), respectively. A higher proportion of Group B lymphomas were low-grade (77% vs. 47% [Group A] vs. 37% [Group C] p = 0.009). Prior occurrence of either one of these malignancies did not affect the disease-specific survival from the second malignancy. However, continuing mortality from the first malignancy appeared to contribute to a poor overall survival following second malignancy. Group A included 8 patients who developed breast cancer following radiation therapy for Hodgkin's disease after a mean interval of 18 (± 4.3) years. Three of these individuals had coexisting ductal and lobular histology (vs. none of the individuals in Groups B and C, p = 0.02). Another interesting finding was the high incidence of multiple additional malignancies in this patient population. A total of 29 additional neoplasms occurred in 21 (23%) of the 91 study subjects. These malignancies involved a wide variety of organ sites and could not be attributed to the therapy for either the breast cancer or the lymphoma in most cases. The data suggest that individuals who develop both breast cancer and a lymphoproliferative neoplasm are at a high risk for multiple malignancies. Close surveillance of such individuals for additional malignancies and further studies to understand the molecular basis of this predisposition are warranted.? 相似文献
32.
Simple color tests based on an alanyl peptidase reaction which differentiate Listeria monocytogenes from other Listeria species. 总被引:1,自引:0,他引:1 下载免费PDF全文
The hydrolysis of DL-alanine-beta-naphthylamide and D-alanine-p-nitroanilide for identification of Listeria spp. has been studied with 227 cultures. All species of Listeria, except L. monocytogenes, hydrolyzed these substrates. The reactions were detected by simple chromogenic reactions and could substitute for the CAMP test. 相似文献
33.
M. A. Pfaller A. L. Barry L. D. Sabath B. N. Kreiswirth P. R. Murray P. C. Fuchs J. C. McLaughlin 《European journal of epidemiology》1993,9(6):658-662
The in vitro activity of ceftriaxone and six additional antimicrobial agents (ceftizoxime, cefoperazone, cefuroxime, fleroxacin, ciprofloxacin, and trimethoprim/sulfamethoxazole) was assessed or 602 recent clinical isolates of staphylococci from six geographically distinct medical centers in North America. All seven antimicrobial agents were active (90–100% of strains susceptible) against oxacillin-susceptible (OS) strains of Staphylococcus aureus (OSSA) and coagulase-negative staphylococci (OSCNS) but had limited activity against oxacillin resistant (OR) staphylococci. Our assessment of the in vitro antistaphylococcal activity of ceftriaxone against contemporary isolates of Staphylococcus aureus and coagulase-negative staphylococci indicates that the activity versus OS staphylococci has not changed over the past decade despite widespread use of the drug. It appears that these agents will continue to be useful for empiric therapy in those centers in which OR strains are uncommon.Corresponding author. 相似文献
34.
McLaughlin DS 《Journal of clinical laser medicine & surgery》1992,10(3):193-198
With proper laser instrumentation, the gynecologic microlaser surgeon enhances his ability to accomplish intra-abdominal fertility-promoting procedures in a safe and efficient manner. 相似文献
35.
36.
Summary Our previous studies have shown that a breakdown in tight junctions in the dystrophic retinal pigment epithelium (RPE) of Royal College of Surgeons' rats is accompanied by changes in intramembrane structure which suggest a redistribution of intramembrane particles. We have now investigated, using thep-nitrophenyl phosphate technique, the possibility that a specific membrane protein, Na-K-ATPase, is redistributed as tight junctions break down in the dystrophic RPE. In the normal RPE, Na-K-ATPase activity is restricted to the apical membrane. Junctional membranes and membranes around phagosomes are free of enzyme activity, suggesting a segregation of the transport enzyme from the Junctional and phagocytic membrane. In the dystrophic RPE, prior to changes in tight junctions, enzyme activity is restricted to the apical membrane. During the initial stages of Junctional breakdown, Junctional membranes and membranes around cytoplasmic inclusions are also labelled. As the breakdown progresses, Na-K-ATPase activity is often present laterally and basolaterally and is sometimes absent apically. Enzyme activity is seen basally only where RPE cells have detached from Bruch's membrane and are superimposed over each other. These changes suggest that Na-K-ATPase redistributes during junctional breakdown, but that attachments between the RPE and Bruch's membrane may restrict the redistribution. The apparent reduction of enzyme activity apically suggests that active transport across the dystrophic RPE may be reduced as the tight junctions break down. 相似文献
37.
Effects of Medicaid drug-payment limits on admission to hospitals and nursing homes 总被引:19,自引:0,他引:19
S B Soumerai D Ross-Degnan J Avorn T j McLaughlin I Choodnovskiy 《The New England journal of medicine》1991,325(15):1072-1077
BACKGROUND. Many state Medicaid programs limit the number of reimbursable medications that a patient can receive. We hypothesized that such limitations may lead to exacerbations of illness or to admissions to institutions where there are no caps on drug reimbursements. METHODS. We analyzed 36 months of Medicaid claims data from New Hampshire, which had a three-drug limit per patient for 11 of those months, and from New Jersey, which did not. The study patients in New Hampshire (n = 411) and a matched comparison cohort in New Jersey (n = 1375) were Medicaid recipients 60 years of age or older who in a base-line year had been taking three or more medications per month, including at least one maintenance drug for certain chronic diseases. Survival (defined as remaining in the community) and time-series analyses were conducted to determine the effect of the reimbursement cap on admissions to hospitals and nursing homes. RESULTS. The base-line demographic characteristics of the cohorts were nearly identical. In New Hampshire, the 35 percent decline in the use of study drugs after the cap was applied was associated with an increase in rates of admission to nursing homes; no changes were observed in the comparison cohort (RR = 1.8; 95 percent confidence interval, 1.2 to 2.6). There was no significantly increased risk of hospitalization. Among the patients in New Hampshire who regularly took three or more study medications at base line, the relative risk of admission to a nursing home during the period of the cap was 2.2 (95 percent confidence interval, 1.2 to 4.1), and the risk of hospitalization was 1.2 (95 percent confidence interval, 0.8 to 1.6). When the cap was discontinued after 11 months, the use of medications returned nearly to base-line levels, and the excess risk of admission to a nursing home ceased. In general, the patients who were admitted to nursing homes did not return to the community. CONCLUSIONS. Limiting reimbursement for effective drugs puts frail, low-income, elderly patients at increased risk of institutionalization in nursing homes and may increase Medicaid costs. 相似文献
38.
Paul E. Baer Lisa Berg Garmezy Robert J. McLaughlin Alex D. Pokorny Mark J. Wernick 《Journal of behavioral medicine》1987,10(5):449-466
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence. 相似文献
39.
There is a new radiochromic film, a highly uniform, thin (100-microns) detector whose sensitive layer (6 microns thick) changes from colorless to blue by dye polymerization without processing, upon exposure to ionizing radiation. Because the dose gradients around brachytherapy sources are steep, the high spatial resolution offered by film dosimetry is an advantage over other detectors such as thermoluminescent dosimeters (TLDs). This compares the photon energy dependence of the sensitivities of GafChromic film, silver halide verification film (Kodak X-Omat V Film), and lithium fluoride TLDs (Harshaw), over the photon energy range 28 keV to 1.7 MeV, which is of interest in brachytherapy. Sensitivity of the radiochromic film is observed to decrease by about 30% as effective photon energy decreases from 1710 keV (4-MV x rays) to 28 keV (60-kV x rays, 2-mm A1 filter). In contrast, the sensitivity of verification film increases by 980% and that of LiF TLDs increases by 41%. The variation of the sensitivity of radiochromic film with photon energy is considerably less than that for silver halide film and similar to that for LiF TLDs, but in the opposite direction. Radiochromic film, like LIF TLDs, does not exhibit the drastic sensitivity changes below 127 keV that silver halide film exhibits. Dose distribution in the immediate vicinity of a high activity (370 GBq) brachytherapy 192Ir source has been mapped using radiochromic film and is presented to illustrate the applicability of this new technology to brachytherapy dosimetry. 相似文献
40.
Increased Escherichia coli enterotoxin detection after concentrating culture supernatants: possible new enterotoxin detectable in dogs but not in infant mice. 下载免费PDF全文
D R Nalin M M Levine C R Young E J Bergquist J C McLaughlin 《Journal of clinical microbiology》1978,8(6):700-703
The heat-stable enterotoxin (ST) of Escherichia coli can be detected by infant mouse or dog intestinal loop tests. These tests differ in that the dog assay uses concentrated culture supernatants and is based on measurements of net intestinal absorption, whereas the mouse test uses unconcentrated supernatants and depends on gross fluid accumulation. To compare the relative sensitivities of these assays, culture supernatants of randomly selected E. coli isolates from 34 Bangalee diarrhea patients were tested for ST in dog loops and infant mice. Supernatants were also tested for heat-labile enterotoxin (LT) in dog loops, Y-1 adrenal cells, and Chinese hamster ovary cells. E. coli supernatants that produced positive responses for both ST and LT in the dog loop assay (ST+/LT+) also produced positive responses when tested for ST in infant mice and for LT in cell lines. Supernatants of strains negative for ST and LT in dog loop (ST-/LT) were also negative in other assays. Of 10 strains positive for just ST in the dog loop test (ST+/LT-), only 5 were ST positive in the standard infant mouse test. Supernatants of the other five strains (dog loop positive, mouse test negative) were then concentrated 100-fold and retested in mice. Three of these five gave consistently positive results after concentration, and two were only intermittently positive. Concentrated supernatants of negative control strains (ST-/LT-) were all negative in mice. The dog assay detects more strains producing ST than the infant mouse test. The infant mouse test, which detects only gross fluid accumulation, failed to detect approximately half of the 10 strains which produced ST alone (ST+/LT-; P = 0.025). Concentrating supernatants for the mouse assay increases sensitivity for detection of ST, but certain E. coli strains produce a variety of ST to which infant mice do not respond. 相似文献