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81.
Differential effects of nitric oxide on erythroid and myeloid colony growth from CD34+ human bone marrow cells 总被引:15,自引:0,他引:15
Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL- 60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S- nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit- granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo. 相似文献
82.
83.
Serogroup B Meningococcal Disease Outbreak and Carriage Evaluation at a College — Rhode Island, 2015
Heidi M. Soeters Lucy A. McNamara Melissa Whaley Xin Wang Nicole Alexander-Scott Koren V. Kanadanian Catherine M. Kelleher Jessica MacNeil Stacey W. Martin Nathan Raines Steven Sears Cynthia Vanner Jeni Vuong Utpala Bandy Kenneth Sicard Manisha Patel 《MMWR. Morbidity and mortality weekly report》2015,64(22):606-607
84.
85.
Borkowsky W Wara D Fenton T McNamara J Kang M Mofenson L McFarland E Cunningham C Duliege AM Francis D Bryson Y Burchett S Spector SA Frenkel LM Starr S Van Dyke R Jimenez E 《The Journal of infectious diseases》2000,181(3):890-896
Children of mothers infected with human immunodeficiency virus type 1 (HIV-1) were immunized at birth and at 1, 3, and 5 months with 1 of 3 doses of recombinant gp120 vaccines prepared from SF-2 or MN strains of HIV-1. A total of 126 children were not infected; 21 received adjuvant only. Vaccine recipients developed lymphoproliferative responses on >/=2 occasions, responding more often to homologous HIV-1 antigens than did adjuvant recipients (56% vs. 14%; P<.001). Responses were appreciated after 2 immunizations and were maintained for >84 weeks after the last immunization. An accelerated immunization schedule (birth, 2 weeks, 2 months, and 5 months) with the lowest dose of the SF-2 vaccine produced responses in all 11 vaccinees by 4 weeks. Responses to heterologous envelope antigens were also detected. Immune responses to vaccination are achievable at an age when some infection (perinatal or breast milk exposure related) may be prevented. 相似文献
86.
Diagnostic accuracy of oropharyngeal cultures in infants and young children with cystic fibrosis. 总被引:3,自引:0,他引:3
M Rosenfeld J Emerson F Accurso D Armstrong R Castile K Grimwood P Hiatt K McCoy S McNamara B Ramsey J Wagener 《Pediatric pulmonology》1999,28(5):321-328
The objective of this study was to assess the diagnostic accuracy of oropharyngeal (OP) cultures relative to simultaneous bronchoalveolar lavage (BAL) cultures in very young children with CF, and to examine the effects of bacterial density, age, and study cohort on diagnostic accuracy. Respiratory culture data were analyzed from three independent, prospective studies involving simultaneous collection of 286 OP and BAL cultures from 141 children with CF <5 years of age. For predicting any growth of Pseudomonas aeruginosa (Pa) from the lower airway in subjects =18 months of age (mean age, 8 +/- 5 months), OP cultures had a sensitivity of 44% (95% CI 14%, 79%), specificity of 95% (90%, 99%), positive predictive value of 44% (14%, 79%), and negative predictive value of 95% (90%, 99%). Diagnostic accuracy was similar for Haemophilus influenzae (Hi). Specificity was significantly lower for Staphylococcus aureus (Sa). Sensitivity for all organisms improved if a positive lower airway culture was defined as >/=10(3) or >/=10(5) cfu/mL. Specificity for Pa declined significantly with increasing age. In children with CF <5 years of age, the specificity and negative predictive value of OP cultures for Pa are high, while the sensitivity and positive predictive value are poor. Thus, in this age range, a negative throat culture is helpful in "ruling out" lower airway infection with Pa. However, a positive culture does not reliably "rule in" the presence of Pa in the lower respiratory tract. These findings may have implications for study design and interpretation as well as clinical management of young children with CF. 相似文献
87.
Coakley G; Mok CC; Hajeer AH; Ollier WE; Turner D; Sinnott PJ; Hutchinson IV; Panayi GS; Lanchbury JS 《Rheumatology (Oxford, England)》1998,37(9):988-991
OBJECTIVE: To examine whether promoter polymorphisms associated with
variation in interleukin-10 (IL-10) production are relevant to the
development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS:
DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The
promoter region between -533 and - 1120 was amplified by polymerase chain
reaction, and polymorphisms detected by restriction enzyme digest or
sequence-specific oligonucleotide probing. RESULTS: We found no significant
difference in allele or haplotype frequencies between the groups.
CONCLUSION: There is no association between FS or RA and these recently
identified IL-10 promoter polymorphisms. Other genetic or environmental
factors could explain the alterations in IL-10 levels seen in these
conditions.
相似文献
88.
Intermittent outpatient ultrafiltration for the treatment of severe refractory congestive heart failure 总被引:2,自引:0,他引:2
Sheppard R Panyon J Pohwani AL Kapoor A Macgowan G McNamara D Mathier M Johnston JR Murali S 《Journal of cardiac failure》2004,10(5):380-383
BACKGROUND: Patients with severe congestive heart failure (CHF) become refractory to conventional medical therapy, leading to recurrent rehospitalizations. We examined the impact of intermittent outpatient ultrafiltration (UF), using either peritoneal dialysis or hemofiltration, on long-term clinical outcomes in patients with refractory CHF. METHODS AND RESULTS: We analyzed clinical and hemodynamic data in 19 consecutive patients with refractory CHF who received intermittent outpatient UF for at least 1 year between July 1998 and November 2002. The mean left ventricular ejection fraction of all 19 patients was 30.2 +/- 19.0%. All patients (100.0%) were New York Heart Association (NYHA) class IV. Only 5 patients (26.3%) received peritoneal dialysis; the remaining 14 (73.7%) received hemofiltration. There were 6 patients with a normal left ventricular ejection fraction (45%). After UF was started, the number of patients that were considered inotrope-dependent was reduced from 86.4% to 36.8% (P < .005). Compared with the year before UF was initiated, the number of CHF hospitalizations during follow-up was reduced from 2.6 to 0.3 (P < .005), and the NYHA class was improved from 4 to 3.1 (P < .005). Among all patients, 2 deaths were related to complications of UF, and cumulative 1-year survival was 63.2%. CONCLUSION: Our study suggests that UF is a safe, feasible therapy, but it needs further evaluation in carefully designed, prospective, randomized clinical trials. UF has the potential for offering another important therapeutic option for patients with severe and refractory CHF. 相似文献
89.
90.
Howard P. Gutgesell Arthur Garson Dan G. McNamara 《The American journal of cardiology》1979,44(1):96-100
To determine the prognosis for the newborn with transposition of the great arteries, the clinical course of 112 consecutive neonates with dextro-transposition was reviewed. Patients were managed with balloon atrial septostomy at initial cardiac catheterization, palliative operation if needed in the 1st year of life and Mustard's intraatrial baffle repair.The 1st month of life was the period of greatest risk (8 percent mortality rate). Between balloon septostomy and baffle repair, 14 of 103 patients at risk (14 percent) either died or had a cerebrovascular accident. The mortality rate at baffle repair was 14 percent (10 deaths in 71 patients), and there were 3 late postoperative deaths. Actuarial analysis of the data indicates that with this plan of management, approximately 50 percent of newborns with transposition of the great arteries will survive 5 years with excellent function and an additional 15 to 20 percent will survive with one or more medical handicaps. 相似文献