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61.
The cause of incontinence in a group of 11 girls (mean age 18 +/- 3 years) who had undergone internal urethrotomy during childhood was assessed. Urodynamic methods were used to characterize the detrusor, and urethral profiles were performed to identify the impact of the operation on the extrinsic and intrinsic mechanisms of urethral closure. The results show that 4 of 11 patients demonstrated detrusor instability associated with a high voiding flow rate. The average resting urethral closure pressure in all patients showed significant reduction in maximum closure pressure (62 +/- 32 cm. water) when compared to normal age-matched controls. Transmission pressures to coughing demonstrated a high percentage of transmission to the distal and mid urethra (180 +/- 20 per cent). It was concluded that the intrinsic mechanism of urethral continence as measured by the resting urethral pressure profile was compromised by the urethrotomy. However, the extrinsic mechanisms as measured by the transmission values was not affected. On the basis of these findings it is argued that internal urethrotomy compromises the closure mechanisms intrinsic to the urethra. Continence in these patients most likely is maintained by the action of extrinsic factors transmitting high closure pressures at the distal third of the urethra. Finally, it is postulated that urethrotomy patients are at increased risk for stress incontinence at an early age. 相似文献
62.
Josef Georg Heckmann Tamara Fischer Ruben Maida Juan Carlos Jesus Galeote 《Zeitschrift fur Gesundheitswissenschaften》1998,6(2):166-177
The Chiquitano-tribe lives in the southern Amazonas region in Bolivia, remote from larger towns. A study (n=1514) on morbidity over an one year period (April 1995 till March 1996) and its relation to general and social medicine is given. Most frequently, childreh under 15 years and women in parity age (15–45 years) sought consultation (34,1 %, 42,7 %). Gastrointestinal, respiratoral and gynecological-obstetric diseases were predominant (22,4 %, 16,2 % and 15,7 %). In the dry season, common colds and respiratoral infections represented the major health problem. In the rainy season, infectious diarrhea diseases caused by polluted water as a consequence of extended floods were most frequent. Typical tropical diseases (malaria, Dengue fever, Chagas’ disease, leprosy a.o.) and socially caused diseases (AIDS, dependencies on drugs and alcohol, consequencies of crime) were rarely seen. With respect to severity, 55,8 % of the patients showed mild disorders. More serious diseases were observed in 39, 8 %. 4,6 % of the patients were diagnosed severly ill and needed hospitalization. Epidemiological data on general and social medicine of minorities in developing countries and their actual degree of medical care are important in a shrinking world. The data are useful to estimate medical needs and plan improvements to the health care system especially in rural areas. 相似文献
63.
Karen J. Chandross David C. Spray Rick I. Cohen Nalin M. Kumar Marian Kremer Rolf Dermietzel John A. Kessler 《Molecular and cellular neurosciences》1996,7(6):479-500
Schwann cell responses to nerve injury are stimulated, in part, by inflammatory cytokines. This study compares changes in the phenotype of cultured Schwann cells after exposure to the cytokine tumor necrosis factor (TNF)-α or the mitogen neu differentiation factor (NDF)-β. TNFα inhibited proliferation in a dose-dependent manner without altering Schwann cell survival. TNFα also reduced both gap junctional conductance and Lucifer yellow dye coupling between Schwann cells. Moreover, both P0and glial fibrillary acidic protein (GFAP) immunoreactivity were reduced. By contrast, NDFβ initially had little effect on cell division although it reduced junctional coupling within 8 h. However, by 48 h, NDFβ stimulated proliferation with a concomitant increase in coupling. Dividing Schwann cells (BrdU+) were preferentially dye coupled compared to nondividing cells, indicating an association between proliferation and coupling. Moreover, cultured Schwann cells expressed connexin46 mRNA and protein, and changes in the levels of the protein correlated with the degree of proliferation and coupling. The data thus provide evidence for cytokine-induced modulation of Schwann cell antigenic phenotype, proliferation, and gap junction properties. These observations suggest that enhanced gap junctional communication among Schwann cells after nerve injury could help to coordinate cellular responses to the injury, and that TNFα may be a signal which terminates proliferation as well as junctional communication. 相似文献
64.
Yu L. Liu Stephen J. Riederer Phillip J. Rossman Roger C. Grim Josef P. Debbins Richard L. Ehman 《Magnetic resonance in medicine》1993,30(4):507-511
A technique is described that provides improved reproducibility of breath-holding for MR image acquisition by monitoring the superior-inferior (S/I) position of the diaphragm. The method incorporates detection of the level of inspiration using an MR signal, rapid display to the patient of diaphragm position to enable breath-hold adjustment, and triggering of image data acquisition once appropriate position is attained. The response time of the system is short, approximately 10 ms. Studies in six volunteers using this method demonstrate a considerable decrease in the S/I range of diaphragm position over 10 consecutive periods of suspended respiration. The mean range is 1.3 mm with the system, while it is 8.3 mm without using it is expected that this method will be of assistance in many abdominal and cardiothoracic studies that use breath-hold techniques. 相似文献
65.
Prognostic value of somatosensory- and motor-evoked potentials in patients with a non-traumatic coma
Josef Zentner Alois Ebner 《European archives of psychiatry and clinical neuroscience》1988,237(3):184-187
Summary A total of 28 patients with non-traumatic coma were studied both with somatosensory- and motor-evoked potentials. While somatosensory-evoked potentials (SEP) have proved to be useful in predicting the outcome in patients with severe brain damage, the aim of this study was to find out whether the additional evaluation of motor-evoked potentials (MEP) could contribute to a better prediction of the outcome than SEP alone. Our results clearly indicate that in terms of prognostic value, SEP are superior to MEP. Nine patients with bilaterally preserved MEP died, while all of the patients with bilaterally preserved SEP and a central conduction time 6.5 ms survived, with a Glasgow outcome score of 1 to 3. Therefore, we cannot recommend the inclusion of MEP in the prognostic evaluation of patients with non-traumatic coma. 相似文献
66.
Key words axillary - block 相似文献
67.
The genetic epidemiology of phobias in women. The interrelationship of agoraphobia, social phobia, situational phobia, and simple phobia. 总被引:6,自引:0,他引:6
K S Kendler M C Neale R C Kessler A C Heath L J Eaves 《Archives of general psychiatry》1992,49(4):273-281
In 2163 personally interviewed female twins from a population-based registry, the pattern of age at onset and comorbidity of the simple phobias (animal and situational)--early onset and low rates of comorbidity--differed significantly from that of agoraphobia--later onset and high rates of comorbidity. Consistent with an inherited "phobia proneness" but not a "social learning" model of phobias, the familial aggregation of any phobia, agoraphobia, social phobia, and animal phobia appeared to result from genetic and not from familial-environmental factors, with estimates of heritability of liability ranging from 30% to 40%. The best-fitting multivariate genetic model indicated the existence of genetic and individual-specific environmental etiologic factors common to all four phobia subtypes and others specific for each of the individual subtypes. This model suggested that (1) environmental experiences that predisposed to all phobias were most important for agoraphobia and social phobia and relatively unimportant for the simple phobias, (2) environmental experiences that uniquely predisposed to only one phobia subtype had a major impact on simple phobias, had a modest impact on social phobia, and were unimportant for agoraphobia, and (3) genetic factors that predisposed to all phobias were most important for animal phobia and least important for agoraphobia. Simple phobias appear to arise from the joint effect of a modest genetic vulnerability and phobia-specific traumatic events in childhood, while agoraphobia and, to a somewhat lesser extent, social phobia result from the combined effect of a slightly stronger genetic influence and nonspecific environmental experiences. 相似文献
68.
Measured attenuation correction methods 总被引:1,自引:0,他引:1
Hermann Ostertag Wolfgang K. Kübler Josef Doll Walter J. Lorenz 《European journal of nuclear medicine and molecular imaging》1989,15(11):722-726
Accurate attenuation correction is a prerequisite for the determination of exact local radioactivity concentrations in positron emission tomography. Attenuation correction factors range from 4–5 in brain studies to 50–100 in whole body measurements. This report gives an overview of the different methods of determining the attenuation correction factors by transmission measurements using an external positron emitting source. The long-lived generator nuclide68Ge/68Ga is commonly used for this purpose. The additional patient dose from the transmission source is usually a small fraction of the dose due to the subsequent emission measurement. Ring-shaped transmission sources as well as rotating point or line sources are employed in modern positron tomographs. By masking a rotating line or point source, random and scattered events in the transmission scans can be effectively suppressed. The problems of measured attenuation correction are discussed: transmission/emission mismatch, random and scattered event contamination, counting statistics, transmission/emission scatter compensation, transmission scan after administration of activity to the patient. By using a double masking technique simultaneous emission and transmission scans become feasible.This article was presented at the 1st EEC workshop on accuracy determination in PET, January 19–20th. 1989 Pisa, Italy (COMAC-BME Concerted Project Characterization and Standardization of PET Instrumentation) 相似文献
69.
Heinz Schurawitzki M.D. Paul C. Hajek Josef Kramer Florian Grabenwöger Walter Klepetko Anton Moritz 《Cardiovascular and interventional radiology》1989,12(1):10-13
In a radiologic search for embolized leaflets of Edwards-Duromedics bileaflet valves in 2 patients, the embolized fragments were localized in the iliac vessels using computed tomography. Sonography was successful in one case and standard X-ray films of the abdomen were negative in both cases.In vitro investigations with Björk-Shiley and Edwards-Duromedics leaflets suggested that standard X-ray films of the abdomen and pelvis should be considered as the first investigational technique. If negative, computed tomography of the lower abdomen should be done. 相似文献
70.
W. W. Dawson R. J. Ulshafer H. M. Engel G. M. Hope M. J. Kessler 《Documenta ophthalmologica. Advances in ophthalmology》1989,71(3):253-263
During (January) 1986–(May) 1988, we examined 272 eyes in 136 rhesus monkeys in the closed Cayo Santiago colony of the Caribbean Primate Research Center of the University of Puerto Rico. Seventy-eight eyes were less than 10 years of age. One hundred and ninety-four were aged 10–28 years. The fundi were examined and photographed. Fluorescein angiography was performed in some eyes. Selected cases were evaluated for acuity loss by recording of pattern-evoked retinal and cortical signals. Light and electron microscopy were used to evaluate the pigment epithelium of some animals. Thirty-eight percent of all eyes had posterior pole drusen. Incidence was highly age-related. When late-stage lesions were found, we did not see neovascularization, but late hyperfluorescence was consistent with degenerative scarring and atrophy. Electrophysiology demonstrated moderately reduced acuity in the presence of numerous macular drusen. Electrooculograms were low normal. Histopathology showed changes identical to those reported in human age-related macular degeneration. No eyes less than 10 years of age had confluent drusen or disciform-like lesions. The incidence of drusen in samples of some social groups was much higher than others. 相似文献