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31.
A V Pinto V F Ferreira R S Capella B Gilbert M C Pinto J S da Silva 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(4):609-610
Accidental transmission of Chagas disease to man by blood transfusion is a serious problem in Latin America. This paper describes the testing of several naphthoquinones, some of which were active against blood trypomastigotes in vitro at 4 degrees C and might therefore warrant further study for preventing transmission of Chagas disease by blood transfusion. 相似文献
32.
Ronald J. Hogg Fred G. Silva Philip L. Berry James E. Wenz 《Pediatric nephrology (Berlin, Germany)》1993,7(1):27-31
We report clinical and pathological data in 56 adolescents presenting with gross hematuria (GH) and 65 presenting with idiopathic nephrotic syndrome (INS). IgA nephropathy (present in 52%) and other mesangial lesions were found in the majority of the 56 patients with GH. Many of these patients had complex urological procedures prior to consideration of a nephrological problem. This often led to significant delays in making the appropriate diagnosis. Pathological lesions in the 65 patients with INS included minimal change NS (MCNS) in 31%, membranous glomerulonephritis (MGN) and focal segmental glomerulosclerosis (FSGS) in 18.5% each, and membranoproliferative GN (MPGN) in 12%. In 47 of the patients with INS, in whom no specific treatment had been given prior to renal biopsy, MCNS and MGN were observed with a similar frequency (26% and 23%, respectively), with FSGS and MPGN being found in 21% and 11%. These results indicate that the pathological lesions in adolescents with INS who undergo a renal biopsy more closely resemble those in adults, and are usually more severe than those in young children. However, it should be noted that our study was retrospective. Hence, there were probably some adolescents with INS who had a successful response to therapy and therefore did not have a renal biopsy performed.
Southwest Pediatric Nephrology Study Group (Central Office, Baylor University Medical Center at Dallas, Tex., USA). Director, Ronald J. Hogg; Associate Directors, Fred G. Silva and F. Bruder Stapleton; Statistician, Joan S. Reisch; Administrative Assistant, Kaye Green. Participating Centers—Baylor College of Medicine, Houston, Tex.: Phillip L. Berry, L. Leighton Hill, Sami A, Sanjad, Edith Hawkins; Baylor University Medical Center, Dallas, Tex.: Ronald J. Hogg, Kaye Green; Tulane University Medical Center, New Orleans, La.: Frank Boineau, John E. Lewy, Radhakrishna Baliga, Patrick Walker; University of Arkansas, Little Rock, Ark.: Watson Arnold, Eileen Ellis, Edward Uthman; University of Colorado Health Science Center, Denver, Colo.: Gary M. Lum, Wiliam Hammond; University of Oklahoma Medical Center, Oklahoma City, Okla.: James Wenzl, James Matson, Geoffrey Altshuler, Sarah Johnson; University of Tennessee, Memphis, Tenn.: F. Bruder Stapleton, Shane Roy, III, Robert J. Wyatt, Charles McKay, William Murphy; University of Texas Health Science Center at Dallas, Tex.: Billy S. Arant Jr, Michel Baum, Fred G. Silva, Arthur Weinberg, Craig Argyle, Joseph Rutledge, Ed Eigenbrodt; University of Texas Medical School, Houston, Tex.: Susan B. Conley, Jacques Lemine, Ron Portman, Ann Ince, Regina Verani; University of Texas Health Science Center at San Antonio, Tex.: Michael Foulds, Sudesh Makker, Kanwal Kher, Melanie Sweet, Victor Saldivar, Fermin Tio; University of Texas Medical Branch, Galveston, Tex.: Ben H. Brouhard, Alok Kalia, Luther B. Travis, Lisa Hollander, Tito Cavallo, Srinivasan Rajaraman; University of Utah Medical Center, Salt Lake City; Utah: Eileen Brewer, Richard Siegler, Elizabeth Hammond, Theodore Pysher.
Note that this list reflects the investigators' addresses and positions during the period of this study and not necessarily their current situations. 相似文献
33.
Diagnosis of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes in a Chinese family by PCR/restriction enzyme analysis 总被引:1,自引:0,他引:1 下载免费PDF全文
C W Lam K Jain K Y Chan D K Silva Y W Chan L J C Wong 《Journal of clinical pathology》1995,48(5):M285-M288
The clinical presentation and the biochemical and molecular genetic findings are described in a 13 year old Chinese boy with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes). The diagnosis was initially suspected because of the characteristic clinical features and the strong family history of convulsions. Using polymerase chain reaction—restriction enzyme analysis, the heteroplasmic nt3243 A→G mutation in mtDNA of peripheral blood leucocytes and a muscle sample was demonstrated. The oligosymptomatic relatives were then screened by this method and the degree of heteroplasmy was analysed. This appears to be the first report of a MELAS family in Hong Kong with this described mutation. Molecular genetic techniques are advantageous in the diagnosis of MELAS. 相似文献
34.
Razeq Shetab Stuart H. Cohen Thomas Prindiville Yajarayma J. Tang Mary Cantrell Darush Rahmani Joseph Silva Jr. 《Journal of clinical microbiology》1998,36(6):1729-1732
Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases. 相似文献
35.
36.
C. M. A. Pennartz R. F. Ameerun H. J. Groenewegen F. H. Lopes da Silva 《The European journal of neuroscience》1993,5(2):107-117
Extra- and intracellular recordings in slices were used to examine what types of synaptic plasticity can be found in the core of the nucleus accumbens, and how these forms of plasticity may be modulated by dopamine. Stimulus electrodes were placed at the rostral border of the nucleus accumbens in order to excite primarily infralimbic and prelimbic afferents, as was confirmed by injections of the retrograde tracer fluoro-gold. In extracellular recordings, tetanization induced long-term potentiation (LTP) of the population spike in 20 out of 53 slices. The presynaptic compound action potential did not change following LTP induction. For the intracellularly recorded excitatory postsynaptic potential, three types of synaptic plasticity were noted: long-term potentiation (16 out of 54 cells), decremental potentiation (eight cells) and long-term depression (LTD; six cells). No correlation was found between the occurrence of potentiation or depression and various parameters of the tetanic depolarization (e.g. peak voltage, integral under the curve). The N -methyl- d -aspartate receptor antagonist d (–)-2-amino-5-phosphonopentanoic acid (50 μM; d -AP5) reduced, but did not completely prevent, the induction of LTP. The incidence of LTD was not markedly affected by d -AP5. No difference in LTP was found when comparing slices bathed in dopamine (10 μM) and controls. Likewise, slices treated with a mixture of the D1 receptor antagonist Sch 23390 (1 μM) and the D2 antagonist S (–)-sulpiride (1 μM) generated a similar amount of LTP as controls. In conclusion, both LTP and LTD can be induced in a key structure of the limbic-innervated basal ganglia. LTP in the nucleus accumbens strongly depends on N -methyl- d -aspartate receptor activity, but is not significantly affected by dopamine. 相似文献
37.
Mariana Diniz Bisi Santos Arthur Braga Pfeifer Marcos Rogério Pupo Silva Claudio Luiz Sendyk WIlson Roberto Sendyk 《Journal of applied oral science : revista FOB》2007,15(2):148-151
One of the causes of implant failures in cemented implant-retained prostheses is the fracture of abutment screw or UCLA abutment. This article reports a case of simultaneous fracture of two UCLA abutments screws occurring in an implant-supported prosthesis placed in the mandibular molar region. The fractured structures were examined under scanning electron microscopy to investigate the probable causes of the failure, which were not related to failures on materials or fabrication of the screws, but rather were due to shear forces. The misfit in cemented prostheses may be the most likely cause of shear force generation. 相似文献
38.
M Salim-Hanna A M Edwards E Silva 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1987,57(2):155-159
Studies in animals have suggested that the products of the irradiation of tryptophan in the presence of riboflavin may play a role in the development of hepatic dysfunction during parenteral nutrition. In this paper we describe the formation of an adduct between tryptophan and riboflavin obtained as a consequence of an anaerobic irradiation of these compounds. Through the use of molecular sieves and of an ion-exchange resin it was possible to separate the photo-adduct from the dimer riboflavin and other reaction products. The various fractions were characterized on the basis of their absorption and emission spectra. Also used were measures of anisotropy of fluorescence emission in order to characterize the derived adduct. 相似文献
39.
F. M. O. Silva J. E. Vergara‐Parente J. K. N. Gomes M. N. Teixeira R. P. Lima 《Transboundary and Emerging Diseases》2007,54(3):119-122
Serum chemistry analyses represents a fundamental tool for the diagnosis and understanding of diseases in marine mammals. Although several studies are being conducted within the field of clinical pathology, haematological and serum chemistry data for Antillean manatees are deficient. The purpose of this study was to determine serum chemistry values for captive Antillean manatees within the CMA/Ibama facility in Brazil. Serum samples were obtained from five captive adult Antillean manatees fed with seagrass and analysed for aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, urea, creatinine, glucose, triglycerides, cholesterol, total protein, albumin, globulin, phosphate, chloride, calcium and uric acid. Blood chemistry parameters were determined using a semi‐automatic analyzer. Maximum, minimum, mean and standard deviations were calculated for each serum chemistry parameter. Differences on the values of males and females were verified using an unpaired Student's t‐test. All the parameters analysed were similar between sexes, with exception of AP, which was higher in females (191.43 ± 31.86 U/l). Alanine aminotransferase and uric acid values for Trichechus manatus manatus are reported for the first time in this paper. This study is the first to report serum chemistry parameter values for long‐term captive male and female Antillean manatees. Therefore, the lower values of albumin, phosphate, chloride, cholesterol and triglycerides obtained here highlight the importance of clinical pathology during health monitoring of captive marine mammals. 相似文献
40.
Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献