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81.
Richards AJ; Yates JR; Williams R; Payne SJ; Pope FM; Scott JD; Snead MP 《Human molecular genetics》1996,5(9):1339-1343
Stickler syndrome (hereditary arthro-ophthalmopathy) is the commonest
inherited cause of retinal detachment and one of the commonest autosomal
dominant connective tissue dysplasias. There is clinical and locus
heterogeneity with about two thirds of families linked to the gene encoding
type II procollagen (COL2A1). Families with Sticklers syndrome type 1 have
a characteristic congenital vitreous anomaly and are linked without
recombination to markers at the COL2A1 locus. In contrast families with the
type 2 variety have a different vitreo- retinal phenotype and are not
linked to the COL2A1 gene. Type XI collagen is a quantitatively minor
fibrillar collagen related to type V collagen and associated with the more
abundant type II collagen fibrils. A mutation in COL11A2, the gene for
alpha 2 (XI) procollagen, has recently been found in a family described as
having Stickler syndrome, although there was no ocular involvement. Here we
show for the first time that a family with the full Type 2 Stickler
syndrome including vitreous and retinal abnormalities is linked to the
COL11A1 gene and characterise the mutation as a Glycine to Valine
substitution at position 97 of the triple helical domain caused by a single
base G-- >T mutation. These results are the first to provide
confirmation that type XI collagen is an important structural component of
human vitreous. They also support previous work suggesting that mutations
in the genes encoding collagen XI can give rise to some manifestations of
Stickler syndrome, but of these, only mutations in COL11A1 will give the
full syndrome including the vitreo-retinal features.
相似文献
82.
Background
Interventions aimed at behavior change are increasingly being delivered over the Internet. Although research on intervention effectiveness has been widely conducted, their true public health impact as indicated by reach, effectiveness, and use is unclear.Objective
The aim of this paper is to (1) review the current literature on online prevention aimed at lifestyle behaviors, and (2) identify research gaps regarding reach, effectiveness, and use.Methods
A systematic search in PubMed revealed relevant literature published between 2005 and 2012 on Internet-delivered behavior change interventions aimed at dietary behaviors, physical activity, alcohol use, smoking, and condom use. Our search yielded 41 eligible reviews, which were analyzed in terms of reach, effectiveness, and use according to the RE-AIM framework.Results
According to health priorities, interventions are largely targeted at weight-related behaviors, such as physical activity and dietary behavior. Evaluations are predominantly effect-focused and overall effects are small, variable, and not sustainable. Determinants of effectiveness are unclear; effectiveness cannot yet be unambiguously attributed to isolated elements. Actual reach of interventions is undiversified, mostly reaching participants who are female, highly educated, white, and living in high-income countries. One of the most substantial problems in online prevention is the low use of the interventions, a phenomenon seen across all behavior domains.Conclusions
More research is needed on effective elements instead of effective interventions, with special attention to long-term effectiveness. The reach and use of interventions need more scientific input to increase the public health impact of Internet-delivered interventions. 相似文献83.
G Cheng ; DS Chiu ; AS Chung ; HF Wong ; MW Chan ; YK Lui ; FM Choy ; JC Chan ; AH Chan ; ST Lam ; TC Fan 《Transfusion》1996,36(4):347-350
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up. 相似文献
84.
Clinical usefulness of K-ras gene mutation detection and cytology in pancreatic juice in the diagnosis and screening of pancreatic cancer. 总被引:6,自引:0,他引:6
J Boadas J Mora E Urgell P Puig M Roca X Cussó G Capellà F Lluís A Farré 《European journal of gastroenterology & hepatology》2001,13(10):1153-1159
BACKGROUND: The significance of K-ras codon 12 mutation in pancreatic juice is still unclear. Although considerable controversy surrounds this question, the diagnostic utility of K-ras in patients with clinical suspicion of pancreatic cancer (PC) and in PC-risk patients remains unknown. OBJECTIVE: To study prospectively the utility of the K-ras gene mutation and cytology in the diagnosis and screening of PC, and to assess its contribution to clinical decision making. METHODS: Pancreatic juice samples obtained from 90 patients were evaluated prospectively. Group I (n = 40) comprised patients with clinical suspicion of PC; group II (n = 50) comprised 49 patients with chronic pancreatitis and one patient proceeding from a PC family screening. The K-ras mutation was detected by means of artificial restriction fragment length polymorphisms (RFLP) in DNA after polymerase chain reaction (PCR) amplification. RESULTS: In group I, of those patients with a definitive diagnosis of PC, malignant cells were found in 27% and K-ras mutation in 44%. In five cases, molecular analysis contributed to diagnosis (4/11 with negative cytology and 1/2 with insufficient cytological material). K-ras mutation revealed an early tumour in one patient, and was the only sample available for diagnosis in another. In group II, the K-ras gene mutation was detected in 8/49 patients (16%) with chronic pancreatitis, one of whom developed PC (2%). CONCLUSIONS: K-ras mutation analysis of pancreatic juice may complement cytological evaluation in the diagnosis of PC, in spite of its limited contribution to clinical decision making. The presence of K-ras mutation in chronic pancreatitis classifies a subgroup of PC-risk patients who should be evaluated carefully by long-term follow-up. 相似文献
85.
Characterization and functional analysis of adult human bone marrow cell subsets in relation to B-lymphoid development 总被引:2,自引:2,他引:2
Pontvert-Delucq S; Breton-Gorius J; Schmitt C; Baillou C; Guichard J; Najman A; Lemoine FM 《Blood》1993,82(2):417-429
To study the frontiers between pluripotent stem cells and committed progenitors and to further define the B-cell pathway in adult bone marrow (BM), CD34+ subpopulations and CD34- B-lineage cells were analyzed by multiparameter flow cytometry, studied by light and electron microscopy, and in short-term and long-term cultures (LTC). While the total CD34+ cells represent 4.9% +/- 0.8 of BM mononuclear cells within the lymphoid-blast window, 73.8 +/- 3.5%, 14.4 +/- 1.8% and 8.8 +/- 2.9% of them were CD34+ CD10- CD19-, CD34+ CD10+ CD19+, and CD34+ CD10+ CD19-, respectively. CD34+ CD10+ CD19+ cells represent a smal homogeneous TdT4 c micro-blast population. Although expressing CD38 and high level of HLA-DR antigens, like myeloid committed progenitors, they did not generate LTC, myeloid, and T lymphoid colonies suggesting that the CD34+ CD10+ CD19+ population represents exclusively B lymphoid committed progenitors. By contrast, all myeloid progenitors and LTC-initiating cells were found in the CD34+ CD10- CD19- cell fraction. This fraction appeared more heterogeneous and contained CD38- HLA-DRlow small cells, larger blasts, and promonocyte-like cells exhibiting small peroxidase-positive granules. Interestingly, CD10 was also present on CD34+ CD19- cells. This population mainly coexpressed CD33 and gave rise to macrophagic colonies. 相似文献
86.
Humphrey RW; O'Brien TR; Newcomb FM; Nishihara H; Wyvill KM; Ramos GA; Saville MW; Goedert JJ; Straus SE; Yarchoan R 《Blood》1996,88(1):297-301
Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed. 相似文献
87.
Vasoactive intestinal peptide, one of the putative neurotransmitters of non-adrenergic inhibitory nerves in human airways, is a potent relaxant of human airways in vitro. Previous in vivo studies of infused vasoactive intestinal peptide in asthmatic subjects have shown only a small bronchodilator effect, which may have been secondary to the cardiovascular effects of the peptide. The effect on airway function of infused vasoactive intestinal peptide was studied in normal subjects, who readily develop bronchodilation in response to a beta agonist. Separate experiments were designed to assess whether there is any synergy between this peptide and the beta agonist isoprenaline. Incremental doses of 1, 3, and 6 pmol/kg/min of vasoactive intestinal peptide were infused for 15 minutes. At 6 pmol/kg/min it caused a mean fall in systolic blood pressure from 108 to 88 mm Hg and a rise in heart rate from 71 to 95 beats/min. There was no significant change in specific airways conductance (sGaw) at any dose of vasoactive intestinal peptide. No significant changes were found with placebo. Isoprenaline (400 microgram) given by inhalation at the end of the infusion produced a mean increase in sGaw of 50%. Infused peptide caused no significant change in the cumulative dose-response curve for inhaled isoprenaline. The lack of effect of vasoactive intestinal peptide on airway responses in vivo may be due to rapid enzymatic breakdown of the peptide or to the fact that dosage has to be limited by the cardiovascular effects. 相似文献
88.
Characterization of a new non-Hodgkin's lymphoma cell line (NCEB-1) with a chromosomal (11:14) translocation [t(11:14)(q13;q32)] 总被引:2,自引:2,他引:2
Saltman DL; Cachia PG; Dewar AE; Ross FM; Krajewski AS; Ludlam C; Steel CM 《Blood》1988,72(6):2026-2030
A new cell line, NCEB-1, was established by Epstein-Barr virus (EBV) transformation of peripheral blood mononuclear cells from a patient with centroblastic-centrocytic diffuse lymphoma expressing IgM lambda. The transformed cells were lymphoblastoid, with many cells showing a plasmacytoid morphology. The NCEB-1 cells had cytoplasmic Ig (CyIg), with loss of the surface Ig (SIg) expression. Cytogenetic analysis of the cell line demonstrated two clones with variations: a hypodiploid clone, with a complex karyotype including a t(11;14)(q13;q32) similar to the original tumor cells, and a near tetraploid clone with the same markers. Southern blot analysis of DNA from the patient's neoplastic cells and NCEB-1 demonstrated identical Ig heavy chain gene rearrangement, confirming the origin of the cell line. The cell line was not tumorigenic when tested in an in vitro assay using immunosuppressed mice. NCEB-1 has been in continuous culture for 9 months and will be valuable for the in vivo study of non-Hodgkin's lymphoma and EBV transformation. 相似文献
89.
Muscle enzyme and fiber type‐specific sarcomere protein increases in serum after inertial concentric‐eccentric exercise 下载免费PDF全文
G. Carmona M. Guerrero R. Cussó J.M. Padullés G. Moras M. Lloret J.L. Bedini J.A. Cadefau 《Scandinavian journal of medicine & science in sports》2015,25(6):e547-e557
Muscle damage induced by inertial exercise performed on a flywheel device was assessed through the serum evolution of muscle enzymes, interleukin 6, and fiber type‐specific sarcomere proteins such as fast myosin (FM) and slow myosin (SM). We hypothesized that a model of muscle damage could be constructed by measuring the evolution of serum concentration of muscle proteins following inertial exercise, according to their molecular weight and the fiber compartment in which they are located. Moreover, by measuring FM and SM, the type of fibers that are affected could be assessed. Serum profiles were registered before and 24, 48, and 144 h after exercise in 10 healthy and recreationally active young men. Creatine kinase (CK) and CK‐myocardial band isoenzyme increased in serum early (24 h) and returned to baseline values after 48 h. FM increased in serum late (48 h) and remained elevated 144 h post‐exercise. The increase in serum muscle enzymes suggests increased membrane permeability of both fast and slow fibers, and the increase in FM reveals sarcomere disruption as well as increased membrane permeability of fast fibers. Consequently, FM could be adopted as a fiber type‐specific biomarker of muscle damage. 相似文献
90.
Holgate ST Bousquet J Chung KF Bisgaard H Pauwels R Fabbri L Rabe K Doherty M Snell NJ Cuss F D'Amato M Reginster JY;Group for the Respect of Ethics Excellence in Science: Asthma section 《Respiratory medicine》2004,98(6):479-487
With new drugs being introduced to treat asthma it is timely to review criteria that can be used to assess efficacy in clinical trials. Anti-asthma drugs are classified into symptoms-modifying, symptom preventers and disease modifying agents. Attention is drawn to the types of experimental evidence required in preclinical studies to support further clinical development of a new therapy. Clinical trials demand careful selection of patients to maximise the strength of the efficacy signal according to the type of trial being designed. While provocation tests are useful in suggesting efficacy, negative tests do not necessarily indicate lack of anti-asthma activity. Therapeutic trial designs need to take account of duration of treatment, dose-response relationships and confirmatory trials. Outcome measures include symptoms, lung function, reduction in concomitant medication, exacerbations, quality of life and measures of inflammation. Interpretation of results need to include the clinical relevance of any changes as well as statistical significance. Special consideration needs to be given to the evaluation of drugs for acute severe asthma, asthma in children and older people, co-morbidity such as rhinitis, and inhaler devices. As with all drugs introduced into practice, careful attention needs to be paid to both short- and long-term safety. 相似文献