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51.
T Gj?rup E Agner L Bording Jensen A M?rup Jensen K M M?llmann 《Acta radiologica (Stockholm, Sweden : 1987)》1987,28(4):421-423
Patients with upper abdominal pain are often examined with both double contrast study of the stomach and endoscopy. On the basis of the results of the two examinations four diagnostic criteria of an ulcer can be formed: 1) radiography reveals an ulcer, 2) endoscopy reveals an ulcer, 3) both radiography and endoscopy reveal an ulcer, and 4) radiography and/or endoscopy reveals an ulcer. In a prospective study the accuracy of each of the four diagnostic criteria was examined. Eighty-two randomly selected outpatients had a double contrast barium examination and an upper gastrointestinal endoscopy performed by staff personnel. The diagnosis of a specialist in upper gastrointestinal endoscopy was used as the standard. For the four diagnostic criteria the overall accuracy ranged from 0.80 to 0.88. The predictive value of a positive test result was around 0.70 and the predictive value of a negative test result ranged from 0.81 to 0.96. The specificity ranged from 0.87 to 0.95, and the sensitivity from 0.38 to 0.90. It is concluded that from a clinical point of view, the accuracy of the four diagnostic criteria does not differ to an extent that justifies recommendation of one diagnostic criterion of gastric ulcer rather than the other. 相似文献
52.
H S Jensen N Tvede M Diamant H H Mogensen M B Hansen B S Thomsen P B Pedersen K Bendtzen 《Scandinavian journal of rheumatology》1991,20(2):83-90
Synovial fluid (SF) and blood from 24 patients with non-traumatic, sterile hydarthron were examined for monocyte elastolysis (M?E) and for levels of interleukin 6 (IL-6) and of soluble interleukin 2 receptor (sIL-2R). Six patients had osteoarthrosis (OA) and 18 patients had inflammatory hydarthron (IH), 10 of whom had rheumatoid arthritis (RA). Blood M?E was lower in OA than in IH, both measured as basal M?E activity and after in vitro stimulation with immune complexes and phorbol myristate acetate (PMA). SF M?E was higher than M?E in blood (p less than 0.01). This increase in SF M?E could be mimicked in vitro by prestimulation of blood M? with low levels of IC. SF IL-6 and sIL-2R were also elevated (p less than 0.01). All three parameters correlated to the degree of joint inflammation evaluated by SF leucocyte level, complement activation, blood C Reactive Protein, and to the clinical evaluation of the joint. The increase in SF M?E, IL-6 and sIL-2R in patients with IH, points to a stimulation of M? and lymphocytes in the joint. 相似文献
53.
Judy Rashotte Louise Jensen 《Revue canadienne de recherche en sciences infirmières》2007,39(4):95-115
This article explores the relationship of ethics to validity in hermeneutic phenomenological inquiry. First, the authors present a brief overview of the various discourses on validity in qualitative research that have been variously applied to hermeneutic phenomenological inquiry. Next, they examine how relational ethics is a presence to bear within this form of inquiry. Finally, they offer a set of ethical reflections to help the researcher engage in a process of ethical questioning during each step of the research process. 相似文献
54.
P A Jensen W F Todd G N Davis P V Scarpino 《American Industrial Hygiene Association journal》1992,53(10):660-667
The need to quantify airborne microorganisms in the commercial microbiology industry (biotechnology) and during evaluations of indoor air quality, infectious disease outbreaks, and agriculture health investigations has shown there is a major technological void in bioaerosol sampling techniques to measure and identify viable and nonviable aerosols. As commercialization of microbiology increases and diversifies, it is increasingly necessary to assess occupational exposure to bioaerosols. Meaningful exposure estimates, by using area or environmental samplers, can only be ensured by the generation of data that are both precise and accurate. The Andersen six-stage viable (microbial) particle sizing sampler (6-STG) and the Ace Glass all-glass impinger-30 (AGI-30) have been suggested as the samplers of choice for the collection of viable microorganisms by the International Aerobiology Symposium and the American Conference of Governmental Industrial Hygienists. Some researchers consider these samplers inconvenient for evaluating industrial bioprocesses and indoor or outdoor environments. Alternative samplers for the collection of bioaerosols are available; however, limited information has been reported on their collection efficiencies. A study of the relative sampling efficiencies of eight bioaerosol samplers has been completed. Eight samplers were individually challenged with a bioaerosol, created with a Collison nebulizer, of either Bacillus subtilis or Escherichia coli. The samplers were evaluated under controlled conditions in a horizontal bioaerosol chamber. During each experimental run, simultaneous samples were collected with a reference AGI-30 to verify the concentration of microorganisms in the chamber from run to run and day to day.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
55.
Is diabetic nephropathy an inherited complication? 总被引:15,自引:0,他引:15
K Borch-Johnsen K N?rgaard E Hommel E R Mathiesen J S Jensen T Deckert H H Parving 《Kidney international》1992,41(4):719-722
For yet unidentified reasons less than 50% of patients with insulin-dependent mellitus develop diabetic nephropathy. Genetic factors have been suggested as risk markers for development of nephropathy in diabetes. To further evaluate this hypothesis we studied the prevalence of nephropathy in diabetic siblings of diabetic patients with and without nephropathy. From a representative sample of 619 patients with insulin-dependent diabetes, we identified 20 patients with and 29 patients without nephropathy having diabetic siblings. Diabetic nephropathy (defined as urinary albumin excretion greater than 300 mg/24 hr) was found in 7 out of 21 siblings to patients with nephropathy and 3 out of 30 siblings to normoalbuminuric patients (P less than 0.04). No significant differences between the two groups of siblings with respect to age, diabetes duration, sex distribution, blood pressure or glycosylated hemoglobin A1c-levels were found. A significant correlation within sib-pair of glycosylated hemoglobin A1c was found (r = 0.47; P less than 0.001). We conclude that familial clustering of diabetic nephropathy does occur. This clustering may either be due to genetic inheritance or to sib-similarities due to shared environment, as indicated by the correlation of glycosylated hemoglobin A1c within sib-pairs. 相似文献
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59.
In a prospective, randomized study of insemination with donor semen,
intracervical insemination by straw was compared with insemination using a
cervical cap with an intracervical reservoir. A total of 91 patients
completed 486 treatment cycles. There were no significant differences in
age, parity, indication for insemination by donor, or method of cycle
monitoring between women who became pregnant and those who did not conceive
with either insemination method. In 236 standard intracervical insemination
cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients
conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude
pregnancy rates and the cumulative pregnancy rates calculated by the
Kaplan-Meier life-table method were significantly different (chi(2)-test, P
< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates
in artificial insemination with cryopreserved donor semen may be improved
by the use of a cervical cap when compared to cervical insemination by
straw. The use of the cervical cap may prolong the exposure of the
spermatozoa to the cervical mucus and prevent the backflow of semen into
the vagina.
相似文献
60.