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71.
Alfred C. deCiutiis Charles M. Peterson Margaret J. Polley Linda J. Metakis 《Journal of the National Medical Association》1978,70(7):503-506
Total hemolytic complement activity (CH50), immuno-electrophoretic conversion of Factor B (C3PA), and of C3 were studied in 16 patients with sickle cell disease in a steady state, eight patients in crisis, and ten patients with β-thalassemia major anemia maintained on a constant transfusion regimen. Patients with sickle cell disease in a steady state have moderatley 56 (percent) depressed conversion of Factor B in addition to markedly decreased conversion of C3 in four of ten patients. One of the three sickle cell patients and two of the four thalassemia patients with low C3 conversion levels have died subsequent to the studies. The combination of chronically decreased Factor B conversion in the face of markedly decreased C3 conversion may make these patients occasionally vulnerable to overwhelming infection analagous to the situation seen in postsplenectomy cases. 相似文献
72.
June A Peters Susan T Vadaparampil Joan Kramer Richard P Moser Lori Jo Peterson Court Jennifer Loud Mark H Greene 《Genetics in medicine》2006,8(12):760-770
PURPOSE: This study is part of an ongoing National Cancer Institute multidisciplinary, etiologically-focused, cross-sectional study of Familial Testicular Cancer (FTC). The current report targets interest in clinical genetic testing for susceptibility to FTC. METHODS: Demographics, knowledge, health beliefs, and psychological and social factors were evaluated as covariates related to interest in genetic testing. RESULTS: The majority (66%) of 229 participants (64 affected men, 66 unaffected men, and 99 women) from 47 multiple-case FTC families expressed interest in having a genetic test within 6 months, should such a test become available. Interest was similar among the three subgroups mentioned above. Worries about insurance discrimination based on genetic test results were associated with a significantly lower interest in testing. Alternatively, participants were more likely to be interested in genetic testing if they were younger and had higher levels of family support, a physician's recommendation supporting testing, cancer distress, and a need for information to inform the health care of their children. CONCLUSIONS: This study reveals social and relationship factors that FTC survivors and their relatives considered important when contemplating the use of new genetic technologies. This is the first study describing hypothetical interest in genetic testing for familial testicular cancer. 相似文献
73.
Indirect evidence of bronchial inflammation assessed by titration of inflammatory mediators in BAL fluid of patients with asthma 总被引:10,自引:0,他引:10
J Bousquet P Chanez J Y Lacoste I Enander P Venge C Peterson S Ahlstedt F B Michel P Godard 《The Journal of allergy and clinical immunology》1991,88(4):649-660
Bronchial inflammation is a characteristic of asthma that may be examined indirectly by bronchoalveolar lavage (BAL). Nine normal individuals were compared with 38 age-matched adults with asthma of variable severity to appreciate the importance of cell activation in the severity of asthma. The severity of asthma was appreciated by the clinical score of Aas and the pulmonary function of the patients. FEV1 ranged between 35% and 130% of predicted. The indirect activation of eosinophils (EOSs), mast cells, fibroblasts, and neutrophils was examined by the titration of eosinophil cationic protein (ECP), tryptase, hyaluronan (HA), and myeloperoxidase (MPO) by radioimmunoassay in BAL fluid (BALF) and cytology of BALF. In the adults with asthma, there was a significantly increased number of EOSs and a significantly increased level of all mediators but MPO. MPO levels were increased in seven patients only; three of these patients were previous smokers. Only ECP and HA levels were significantly correlated with the severity of asthma. These results demonstrate EOSs, mast cells, and fibroblasts are activated in asthma, whereas the involvement of neutrophils is less clear. There was a significant correlation between ECP and HA levels, suggesting a common activation of EOSs and fibroblasts. 相似文献
74.
M L Olson C J Shanholtzer K E Willard L R Peterson 《American journal of clinical pathology》1991,96(4):454-458
A slide centrifuge Gram stain procedure was performed to screen for bacteriuria 4161 urine specimens submitted in urine preservative tubes for routine culture. For slide centrifuge Gram staining, each urine sample was mixed well. Thereafter, 0.2 mL of each sample was placed, using a pipette, into a slide centrifuge chamber and centrifuged at 2,000 rpm for 5 minutes. The slides were heat fixed, Gram stained, and read by laboratory personnel who scanned 12 consecutive oil-immersion fields using a set pattern. The presence of the same organism in six or more fields was defined as a positive urine screen. Urine samples were cultured using a 0.001-mL loop and a comparison of culture growth with slide centrifuge screening was made. When growth of 100,000 or more colony-forming units per milliliter (CFU/mL) was the reference for comparison, the screen had a sensitivity rate of 98%, a specificity rate of 90%, a negative predictive value of 99%, and a positive predictive value of 65%. When a lower colony count of 10,000 or more CFU/mL was the reference for comparison, the screen had a sensitivity rate of 88%, a specificity rate of 95%, a negative predictive value of 96%, and a positive predictive value of 84%. The slide centrifuge Gram stain is a very sensitive screening method to detect bacteriuria in an adult male population. 相似文献
75.
Purkinje cell protein-2 regulatory regions and transgene expression in cerebellar compartments 总被引:4,自引:0,他引:4
S Vandaele D T Nordquist R M Feddersen I Tretjakoff A C Peterson H T Orr 《Genes & development》1991,5(7):1136-1148
The Purkinje cell protein 2 (Pcp-2) is expressed in cerebellar Purkinje cells and retinal bipolar neurons. To illuminate how Pcp-2 expression is restricted to only two neuronal types and to derive tools to express heterologous genes in these neuronal subpopulations, genomic sequences of the mouse Pcp-2 gene have been cloned and flanking sequences have been evaluated as a source of neuron-specific regulatory elements. An upstream region with homology to other genes expressed in neurons was identified and a hybrid gene containing this sequence was constructed by ligating 0.4 kb of upstream and 0.3 kb of downstream Pcp-2-flanking DNA to lacZ. Transgenic mice bearing this construct exhibited beta-galactosidase in a wide array of neuron types, suggesting that this sequence may play an important role in specifying neuronal expression. Addition of a further 3.1 kb of Pcp-2 upstream sequences restricted expression of beta-galactosidase to a small number of neuron types and most notably to Purkinje cells within parasagitally oriented cerebellar compartments. The presence of elements lying within the 3.1-kb upstream region and acting to specifically restrict Pcp-2 expression is therefore suggested. Moreover, as beta-galactosidase was not expressed in the bipolar cells of these transgenic mice, retinal expression of the endogenous Pcp-2 gene must involve elements in addition to those conferring expression within Purkinje cells. 相似文献
76.
Zhang ZX Lazdina U Chen M Peterson DL Sällberg M 《Clinical and diagnostic laboratory immunology》2000,7(1):58-63
We have produced a murine monoclonal antibody (MAb), ZX10, recognizing the NTPase/helicase domain of the hepatitis C virus (HCV) nonstructural 3 protein (NS3), from which we designed a single-chain variable fragment (ScFv). The ZX10 MAb recognized a discontinuous epitope of the NTPase/helicase domain, of which the linear sequence GEIPFYGKAIPL at residues 1371 to 1382 constitutes one part. cDNAs from variable regions coding for the heavy and light chains were cloned, sequenced, and assembled into the NS3-ScFv, which was inserted into procaryotic and eucaryotic expression vectors. Escherichia coli-expressed NS3-ScFv inhibited the binding of the ZX10 MAb to NS3, confirming a retained specificity. However, the ability to bind the peptide 1371-1382 had been lost. In vitro-translated NS3-ScFv and HCV NS3/NS4A were coprecipitated by antibodies to HCV NS4A, confirming the in vitro activity of the NS3 ScFv. Thus, we have designed a functional NS3 NTPase/helicase domain-specific ScFv which should be evaluated further with respect to disturbing enzymatic functions of the NS3 protein. 相似文献
77.
Detection of rubella antibodies by hemagglutination inhibition, indirect fluorescent-antibody test, and enzyme-linked immunosorbent assay. 总被引:1,自引:10,他引:1 下载免费PDF全文
M V Zartarian G Friedly E M Peterson L M de la Maza 《Journal of clinical microbiology》1981,14(6):640-645
Using hemagglutination inhibition (HAI) as a reference method, 292 (40 nonimmune, 252 immune) human serum samples were tested by indirect fluorescent antibody (IFA) and enzyme-linked immunosorbent assay (ELISA) for immune status and quantitation of rubella antibodies. The overall agreement with HAI for immune status was 99.7% (291/292) with IFA and 98.6% (288/292) with ELISA. Two specimens (0.7%, 2/292), negative by HAI, were equivocal by ELISA. Initially a 6.5% (19/292) overall disagreement was obtained for immune status evaluation between HAI and IFA, which was reduced to 0.3% (1/292) upon repeat testing. All of these samples were near the immune/nonimmune cutoff point (95 samples), reflecting an initial disagreement of 20% (19/95) in this category (HAI titers less than 1:20). Likewise, an initial overall disagreement of 4.5% (13/292) was obtained between HAI and ELISA which was reduced to 0.7% (2/292) upon repeated testing. Eleven of the 13 samples were near the immune/nonimmune cutoff point, reflecting an initial disagreement of 11.6% (11/95) with sera having an HAI antibody titer of less than 1:20. Quantitation of rubella antibodies by IFA showed an overall correlation with HAI of 86.6% within less than twofold titer and 99.3% within less than fourfold titers. In testing the ability of ELISA to quantitate antibody, a correlation coefficient (r) of 0.996 was obtained by plotting the measured average optical density (405 nm) of ELISA against the corresponding log of HAI titer. Both IFA and ELISA showed good correlation with HAI for immune status evaluation and for quantitation of rubella antibodies. Technically the HAI was the most cumbersome to perform, whereas IFA was the least technically demanding. Originally, 308 samples were tested; 16 samples (5.2%) could not be evaluated by IFA because of a high level of nonspecific fluorescence. The strict requirement of controlling the temperature range (23 to 24 degrees C) during substrate hydrolysis proved to be a problem with the ELISA test in our laboratory. 相似文献
78.
Phagocytosis and killing of staphylococci by human polymorphonuclear and mononuclear leucocytes. 总被引:15,自引:2,他引:15 下载免费PDF全文
The phagocytosis and killing of 3H-thymidine-labelled Staphylococcus aureus by polymorphonuclear leucocytes (PMNs) and monocytes (MNs) obtained from 50 health donors were evaluated. In addition, extracellular factors that might influence phagocytosis and killing were studied. The method described gave highly reproducible results. No significant difference was observed in the phagocytic and killing functions of a single donor's PMNs and MNs when studied several times in one day and longitudinally over a period of 1-12 weeks for six donors tested. Likewise, no signigicant difference in uptake and killing was observed when bacteria were opsonised with sera from 11 different normal donors. When Staph. aureus opsonised with normal serum was added to the leucocytes in a ratio of 10 bacteria: 1 leucocyte, the uptake by PMNs and MNs from 50 donors after 20 minutes' incubation was 85% +/- 7 standard deviation (SD) (range 75-98%) and 69% +/- 11 SD (range 54-90%), respectively. The rate of uptake by MNs in the first three minutes of the assay period was only 60% of that by PMNs. 相似文献
79.
The authors performed whole-blood clotting time (WBCT), activated partial thromboplastin time (APTT), and whole-blood recalcification time (WBRCT) tests on normal blood or citrated plasma, each milliliter containing 0-0.5 unit heparin, and on samples from patients, of whom many were receiving heparin anticoagulation therapy. Six partial thromboplastin reagents were used. Linearity between clotting time and heparin concentration was observed with WBCT and APTT, determined with Hyland partial thromboplastin (kaolin-activated) and Dade ("Improved" Activated Cephaloplastin and Actin) reagents. With a General Diagnostics preparation (Platelin -plus, celite as the activator) and another Hyland partial thromboplastin reagent (silica-activated), the sensitivity to heparin decreased to beyond 0.3 unit/ml plasma. No correlation was observed with the old Dade Activated Cephaloplastin reagent, WBRCT was completely insensitive to heparin in concentrations as high as 0.24 unit/ml blood. With patient samples, correlations were observed between WBCT and Hyland (kaolin) APTT, and between Hyland and Dade Actin APTT. However, WBCT and WBRCT, and APTT and WBRCT, correlated poorly. 相似文献
80.
Synergistic protection against experimental cholera by immunization with cholera toxoid and vaccine. 总被引:2,自引:8,他引:2 下载免费PDF全文
J W Peterson 《Infection and immunity》1979,26(2):528-533
Rabbits were immunized with two parenteral injections of Wellcome toxoid PX389A, Wyeth toxoid 20101, or Merck bivalent vaccine. Other groups of rabbits were immunized with combinations of the Merck vaccine and each of the two toxoids. Antitoxin responses were monitored in each group of rabbits before livecell challenge of each animal by the ligated intestinal loop assay. Inaba and Ogawa strains of Vibrio cholerae were used for challenge experiments. Basically, the data indicate that the toxoids were equivalent in antigenic potency and antitoxin responses were unaffected by combination of the toxoids with the whole-cell vaccine. The 50 microgram doses of each toxoid as well as the 4 X 10(9) cells of the bivalent vaccine provided the same magnitude of protection against live-cell challenge with either Inaba or Ogawa vibrios. Immunization with either toxoid in combination with the bivalent vaccine resulted in a synergistic protective response against live-cell challenge of intestinal loops with V. cholerae. Synergistic protection was observed when toxoid and vaccine were administered together by the oral and parenteral routes. Maximum protection was obtained when rabbits were immunized with the combined toxoid-whole-cell vaccine administered by both oral and parenteral routes. 相似文献