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101.
About 30% of patients who have a Roux-en-Y gastrojejunostomy after gastrectomy suffer from abdominal pain, nausea, vomiting
of food and bloating made worse by eating. This syndrome, called the Roux stasis syndrome, is caused, in part, by a motility
disorder of the Roux limb. Transection of the jejunum during the construction of the limb separates the limb from the natural
small intestinal pacemaker located in the duodenum. Ectopic pacemakers then appear in the limb and trigger retrograde contractions
in its proximal portion. These contractions slow transit through the limb and result in Roux stasis. Current nonsurgical treatment
of the syndrome includes the use of prokinetic agents and intestinal pacing, neither of which has demonstrated long-term benefits.
A near-total gastrectomy may speed upper gastrointestinal transit somewhat, but stasis in the Roux limb often persists. Our
current approach aims at preventing the syndrome by the use of an ‘uncut’ Roux limb, an operation which preserves myoneural
continuity between the duodenal pacemaker and the Roux limb and so prevents the appearance of ectopic pacemakers and stasis
in the limb. 相似文献
102.
103.
Baker CM Ogden SJ Prapaipanich W Keith CK Beattie LC Nickleson LE 《The Journal of nursing administration》1999,29(3):11-20
Nearly three of every five hospitals in the United States have been involved in some form of consolidation during the past 5 years. Within this turbulent hospital merger environment, nurse executives are confronted with organizational, professional, and personal decisions. Stakeholder analysis is offered as one strategy to facilitate effectiveness throughout the hospitals' merger life-cycle. 相似文献
104.
Simons-Morton Bruce G.; Crump Aria Davis; Haynie Denise L.; Saylor Keith E. 《Health education research》1999,14(1):99-107
Adolescent problem behavior, including substance use, schoolmisconduct and delinquency, is a national concern. Implicitin the concept of middle school is the recognition that studentswho develop positive social bonds with their school are morelikely to perform well academically, and refrain from misconductand other antisocial behavior. However, little scientific attentionhas been given to the complex interactions between middle schoolstudents and the school environment. Prior to implementing amiddle school problem behavior prevention program we conducteda survey in the seven middle schools in one US school district.Out of 4668 grade 68 students enrolled, 4263 (91.3%)completed the survey. Studentschool bonding was positivelycorrelated with school adjustment (r = 0.49) and perceived schoolclimate (r = 0.77), but inversely correlated with problem behavior(r = 0.39 to 0.43). Problem behavior was significantlyhigher (P < 0.001) among males than females and among studentsin higher grades. Conversely, school bonding, climate and adjustmentwere significantly higher (P < 0.001) among females thanmales, but declined significantly from one grade to the next.The data support the conclusion that school bonding is associatedwith problem behavior. We describe the development of a multiple-componentintervention in middle schools designed to increase studentschoolbonding and prevent problem behavior. 相似文献
105.
By means of two different types of enzyme-linked immunosorbent assay (ELISA) techniques, antibodies to methadone were detected in blood plasma of heroin addicts on methadone maintenance treatment. In 11-15% of cases immunoglobulin (Ig) M antibodies were detected, while IgG antibodies were observed in 33-40%. At least two types of antibodies to methadone were induced-antibodies with high affinity to methadone and low-affinity antibodies more specific for morphine than for methadone. The methadone antibody-positive group of patients had a significantly higher plasma methadone concentration--440 ng/ml, than the antibody-negative group--250 ng/ml (P < 0.005) despite almost the same mean therapeutic doses of methadone. Of patients with all types of antibodies to methadone 52% were human immunodeficiency virus (HIV)-positive, whereas in the group without antibodies, HIV-positive reactions were observed in 10.5% only (P < 0.002). Alternatively, 87.5% of HIV-positive patients had antibodies to methadone, a fact which should be taken into consideration during methadone dose adjustment. 相似文献
106.
Vree TB Maljers L Van den Borg N Nibbering NM Verwey-van Wissen CP Lagerwerf AJ Maes RA Jongen PJ 《The Journal of pharmacy and pharmacology》1999,51(10):1155-1166
Fourteen metabolites of methylprednisolone have been analysed by gradient-elution high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). The compounds were separated on a Cp Spherisorb 5 microm ODS column connected to a guard column packed with pellicular reversed phase. The mobile phase was an acetonitrile- 1.0% aqueous acetic acid gradient at a flow rate of 1.5 mL min(-1) The analysis gave a complete picture of parent drug, prodrugs and metabolites, and the alpha/beta stereochemistry was resolved. The short (1-2 h) elimination half-life of methylprednisolone is explained by extensive metabolism. The overall picture of the metabolic pathways of methylprednisolone is apparently simple-reduction of the C20 carbonyl group and further oxidation of the C20,C21 side chain (into C21COOH and C20COOH), in competition with or in addition to oxidation at the C6 position. 相似文献
107.
Falloon IR McGill CW Matthews SM Keith SJ Schooler NR 《The Journal of psychotherapy practice and research》1996,5(1):45-56
The NIMH Treatment Strategies in Schizophrenia (TSS) collaborative study group investigated the efficacy of antisychotic drug maintenance strategies involving reduced medication exposure in interaction with applied and supportive family management for the long-term treatment of schizophrenia. Therapy was provided at five centers by 25 clinicians who did not participate in the development of the therapies. They were trained by two of the authors, I.R.H.F and C.W.M, in applied family management, a homebased treatment derived from the behavioral family therapy developed by them. Clinicians' characteristics, selection, and training methods, as well as patient rehospitalization rates, are reported for the two family management conditions. The TSS study represents a bridge between the development of a novel therapy and its dissemination in general clinical practice. 相似文献
108.
D. Keith Rose Robert J. Byrick Marsha M. Cohen Gary M. Caskennette 《Journal canadien d'anesthésie》1996,43(4):333-340
Purpose
To determine which factors influence the clinician in choosing critical care admission and postoperative ventilation, we prospectively examined the incidence, timing, causes, and risk factors for admission to critical care for postoperative ventilation within 48 hr of a surgical procedure (excluding cardiac and neurosurgical).Methods
Patients were categorized as: admission planned preoperatively; admission unplanned and identified in the OR (Operating Room) or PACU (Post Anaesthetic Care Unit); and admission unplanned, identified after PACU discharge. Rates of admission by category for those with specific preoperative and intraoperative characteristics were compared to those without the characteristics to determine risk factors for admission (P < 0.01).Results
Only 329 of 15,059 cases (2.2%) had a critical care admission. Of these, 288 were planned, 31 identified in the OR or PACU, and 10 after PACU discharge. A respiratory aetiology was the reason for admission in 75% of unplanned cases. Preoperatively, age ≥ 60 yr and common systemic illnesses (cardiac, renal, pulmonary) were markers for planned admission, but only positive HIV status was a risk factor for unplanned admission. The two main physiological features which identified all critical care admissions were haemoglobin oxygen saturation <90% (preoperatively breathing room air and intraoperatively) and tachycardia during the operative period. Six of ten of the unplanned after PACU discharge patients underwent bronchoscopy with a neurolept analgesic technique.Conclusion
Postoperative admissions to a critical care unit, both planned and unplanned, are uncommon. This study has identified haemoglobin oxygen desaturation during the perioperative period and intraoperative tachycardia as important markers for all admissions to critical care. 相似文献109.
Fucosidosis: four new mutations and a new polymorphism 总被引:2,自引:0,他引:2
Seo Hee-Chan; Willems Patrick J.; Kretz Keith A.; Martin Brian M.; O'Brien John S. 《Human molecular genetics》1993,2(4):423-429
Fucosidosis is a rare lysosomal storage disease due to a nearlycomplete deficiency of -L-fucosidase (EC 3.2.1.51
[EC]
). In thisstudy, all 8 exons of the -L-fucosidase structural gene (FUCA-1)were amplified by PCR methods, and the amplified products weresubcloned and sequenced. Five patient groups with fucosidosiswere selected according to their ethnic backgrounds and haplotypesfor RFLPs in FUCA-1. Four presumptive disease causing mutationswere detected: 1) A major deletion of DNA containing the lasttwo exons of FUCA-1 in two Algerian siblings. 2) A G to T mutationin exon 6 resulting in an in-frame termination codon (E375X)in eight Hispanic patients from Colorado and New Mexico. 3)A G to A mutation (G60D) in exon 1 in four Italian patientsand in three related French-American (Cajun) patients. ThisG60D mutation creates a unique site for Afl III. 4) A frameshiftmutation resulted from a two-base deletion in exon 2 (K151fs)in an Italian patient. This deletion obliterates a unique BstXIsite and creates a new BpmI site, and was found in only thispatient and in only one allele. The rationale for proposingthese defects as disease causing mutations includes pedigreeanalysis and the predicted consequences of each defect uponthe activity and the concentration of the enzyme. An A to Gtransition (Q281R) in exon 5 was found to be present in homozygousform in affected patients and also in normal subjects; it appearsto be a newly identified polymorphism. It causes a charge changeand may be responsible for the electrophoretic variant phenotypeof fucosidosis. This polymorphism is inherited concordant withthe RFLP PvuIIBglI haplotype 2 2, 2 2.The 4 new mutations identified here comprise 70% of allelesof the 25 fucosidosis patients in our study. 相似文献
110.
Summary Chondrocytes in epiphyseal cartilage were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) using freeze-fracture techniques. Freeze-fracture replicas showed large numbers of fingerlike, 0.11–0.15 m diameter, projections from the chondrocyte surface, with numerous 95–180 Å diameter intramembranous particles associated with both the cell membrane surface and these projections. With SEM, these cytoplasmic projections were also obvious, but appeared collapsed into clusters of globular-shaped projections on the surface of the chondrocytes. With freeze-fracture techniques, in which shrinkage artifacts were essentially eliminated, the cytoplasmic projections were often seen in intimate contact with the extracapsular matrix. However, with chondrocytes prepared by both SEM and conventional TEM, there was evidence of shrinkage, the cytoplasmic projections having little contact with the extracapsular matrix. These findings show that the cytoplasmic processes are not artifacts of tissue processing and provide morphological evidence in support of the hypothesis that matrix vesicles are of cellular origin.Correlation of Freeze-Fracture and Scanning Electron Microscopy of Epiphyseal Chondrocytes 相似文献