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J A Thorp G R Cohen J D Yeast D Perryman C Welsh N Honssinger S Stephenson J Hedrick 《American journal of perinatology》1992,9(1):22-24
Fetal hydrops at 26 weeks' gestation was diagnosed following a massive fetomaternal hemorrhage. Fetal intravascular transfusion was performed, and the hydrops completely resolved within 72 hours. The fetus required one more transfusion at 27 weeks' gestation. A subsequent percutaneous umbilical blood sampling at 30 weeks' gestation demonstrated a normal fetal hematocrit. A vaginal delivery at term resulted in a normal newborn. Massive fetomaternal hemorrhage is a well-known cause of nonimmune hydrops and may occur spontaneously in an otherwise normal pregnancy. Confirmation by percutaneous umbilical blood sampling and treatment by intravascular transfusion is recommended when massive fetomaternal hemorrhage causes hydrops in preterm gestations. 相似文献
23.
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Mary ER O'Brien Janet Hardy Sylvia Tan Jackie Walling Brian Peters Sarah Hatty Eve Wiltshaw 《Cancer chemotherapy and pharmacology》1992,30(3):245-248
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted. 相似文献
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Familial dyslipidemic hypertension. Evidence from 58 Utah families for a syndrome present in approximately 12% of patients with essential hypertension 总被引:17,自引:0,他引:17
R R Williams S C Hunt P N Hopkins B M Stults L L Wu S J Hasstedt G K Barlow S H Stephenson J M Lalouel H Kuida 《JAMA》1988,259(24):3579-3586
Population-based sibships with essential hypertension diagnosed before the age of 60 years are being screened in Utah to find two or more hypertensive siblings with the same biochemical abnormality as a clue to an inherited cause for their specific type of hypertension. Among 131 hypertensive subjects in 58 sibships, concordant abnormalities in fasting serum lipid concentrations were observed in two or more siblings in 48% of the sibships. After adjusting for effects of antihypertensive medications, abnormal values reported in only 10% of the Lipid Research Clinics data were observed in 30% of patients for serum triglycerides, 19% for serum low-density lipoprotein cholesterol, and 39% for high-density lipoprotein cholesterol. More than one lipid level was abnormal in almost all concordant sibships, suggesting an association between hypertension and a syndrome of mixed lipid abnormalities, probably familial combined hyperlipidemia (renamed "familial combined dyslipidemia" because of common low high-density lipoprotein cholesterol levels). We conclude that familial dyslipidemic hypertension may be a specific syndrome with lipid abnormalities more severe than blood pressure elevations. 相似文献
28.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献
29.
Summary Mechanically skinned skeletal muscle fibres of three crustaceans (barnacle, crayfish and crab) and two insects (cockroach and cricket) were activated in Ca2+- and Sr2+-buffered solutions of different concentrations and the isometric force response was determined. The maximum force response induced by Sr2+ (P
0
Sr
) was only 0–10% of that induced by Ca2+ (P
0
Ca
) in all crustacean muscles, but approached 90% in insects. Experiments on barnacle muscle fibres activated simultaneously by Ca2+ and Sr2+ suggested that Sr2+ competes with Ca2+ for binding onto the regulatory sites without, however, being able to turn all of them on as efficiently as Ca2+. Interestingly, the ratioP
0
Sr
/P
0
Ca
and the sensitivity for both Sr2+ and Ca2+ increased substantially after 4–6 h following the dissection of the animals in most intact decapod muscle fibres and after 24 h in most barnacle muscle fibres. The steepness of the activation curves for both Ca2+ and Sr2+ was similar for each muscle regardless of the age of the fibre and implied that more than 2 Ca2+ (2 Sr2+) were involved in the activation process of each muscle.A Ca2+-induced Ca2+ release mechanism of physiological importance was found to operate in all arthropod muscle fibres investigated. 相似文献
30.
Theory and observation of spontaneous oscillatory contractions in skeletal myofibrils 总被引:1,自引:0,他引:1
Summary At low levels of activation, an isometrically-held myofibrillar preparation on the descending limb may exhibit persistent oscillations of period 1–6 s in tension and sarcomere lengths. We propose a sarcomeric theory of spontaneous oscillatory contraction, based on the phenomena of force creep and delayed length activation. The time delay leads to oscillations and controls their period. A computer model using these ideas simulates spontaneous oscillatory contraction for fixed-end fibres only if isometric tension capacity varies slightly along the fibre. The form of this inhomogeneity controls a diversity of spontaneous oscillatory contraction behaviour: the tension waveform can vary from large and sinusoidal to small-amplitude pulses or chaotic behaviour, and these variations are observed in slow-twitch soleus fibres from the same animal (rat). The model predicts that oscillatory and quiescent regions coexist in the fibre, with large-amplitude sawtooth waveforms in sarcomere length in the former as observed. It can also generate travelling-wave structures, similar to those found by the Tokyo group, in oscillating regions when there is a spatial gradient in isometric tension capacity. Phase discontinuities in sarcomere length occur near the oscillatory-quiescent boundary. Predictions for the Ca2+ concentrations and sarcomere lengths in which spontaneous oscillatory contraction occurs and for differences in the spontaneous oscillatory contraction frequencies of fast-and slow-twitch fibres compare well with experiment. Spontaneous oscillatory contraction is also predicted under isotonic conditions. 相似文献