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951.
Catherine Richard Claude Delaude Louisette Le Men-Olivier Jean Le Men 《Phytochemistry》1978,17(3):539-541
The structure of a new bisindole alkaloid has been elucidated by chemical correlation and analysis of 13C NMR spectra. 相似文献
952.
A 13C-NMR study of the biosynthesis of dothistromin by Dothistroma pini was undertaken. The biosynthetic labelling pattern in this bistetrahydr 相似文献
953.
Michael D. Scawen John A.M. Ramshaw Richard H. Brown Donald Boulter 《Phytochemistry》1978,17(5):901-905
The amino acid sequences of the plastocyanins from Mercurialis perennis and Capsella bursa-pastoris have been determined. The amides at positions 64 and 68 in the Mercurialis sequence were positioned by ‘homology’ Both proteins are single polypeptide chains of 99 residues and are closely related to other higher plant plastocyanins. 相似文献
954.
W.David Ollis Brian T. Redman Richard J. Roberts Ian O. Sutherland Otto R. Gottlieb Mauro T. Magalhaães 《Phytochemistry》1978,17(8):1383-1388
The trunkwood of Machaerium kuhlmannii contains methyl palmitate, 3-O-acetyloleanolic acid and sitosterol; the benzene derivatives 2,3-dimethoxyphenol, 2,6-dimethoxyphenol, 2-hydroxy-3-methoxyphenol, 2,3-dimethoxybenzaldehyde and methyl 3-(2-hydroxy-4-methoxyphenyl)-propionate; the isoflavonoids formononetin and (6aS,11aS)-medicarpin; the neoflavonoids (R)-3,4-dimethoxydalbergione, (R)-3,4-dimethoxydalbergiquinol, kuhlmanniquinol [(R)-3-(4-hydroxyphenyl)-3-(5-hydroxy-2,3,4-trimethoxyphenyl)-propene], dalbergin, kuhlmannin (6-hydroxy-7,8-dimethoxy-4-phenylcoumarin) and kuhlmannene (6-hydroxy-7,8-dimethoxy-4-phenylchrom-3-ene), as well as the cinnamylphenol kuhlmannistyrene [Z-1-(5-hydroxy-2,3,4-trimethoxybenzyl)-2-(2-hydroxyphenyl)-ethylene]. Five of these compounds, in addition to (R)-4′-hydroxy-3,4-dimethoxydalbergione, were also isolated from a trunkwood extract of M. nictitans. Structural assignments were confirmed by chemical interconversion and by the synthesis of (±)-kuhlmanniquinol. 相似文献
955.
From February 1972 to August 1974 ten immatureCebus albifrons monkeys were weighed and vaginal swabbing performed at monthly or shorter intervals to determine age and weight at the onset
of puberty. The average weight (±S.E.M.) at birth and at puberty was 226±5.8 g and 1,617±32.45 g, respectively. The average
age at puberty was 3.59±0.17 years. The average weight velocity for all ten monkeys shows the maximum rate of weight gain
to occur shortly after birth and decrease rapidly to its smallest prepubertal increment at nine months of age (weaning). From
nine months there is a post-weaning weight spurt which reaches its greatest velocity at an average age of 15 months. Thereafter,
the weight velocity decreases to its lowest level. Individual weight velocity curves of each of the ten animals show a slight
prepubertal weight spurt which is not obvious in the average growth curve. 相似文献
956.
The theoretical basis is developed for a population model which allows the use of constant temperature experimental data in predicting the size of an insect population for any variable temperature environment. The model is based on a stochastic analysis of an insect's mortality, development, and reproduction response to temperature. The key concept in the model is the utilization of a physiological time scale. Different temperatures affect the population by increasing an individual's physiological age by differing rates. Conditions for the temperature response properties are given which establish the validity of the model for variable temperature regimes. These conditions refer to the relationship between chronological and physiological age. Reasonable agreement between the model and field populations demonstrates the practicality of this approach. 相似文献
957.
The complete nucleotide sequence of the leader RNA synthesized in vitro by the Indiana serotype of vesicular stomatitis virus is presented. The sequence was determined by the technique described by Donis-Keller, Maxam and Gilbert (1977) in combination with the standard two-dimensional fingerprint techniques described by Barrell (1971). The leader RNA contains 48 nucleotides variably terminating at the 3′ terminus with cytosine (68%) and adenosine at position 47 (32%). Since the leader RNA is complementary to the 3′ terminal portion of the viral genome RNA, the first 48 nucleotides from the 3′ end of the genome RNA can be deduced. The leader RNA contains repetitive and palindromic sequences with a polypurine sequence at its 3′ terminus. The possible role of some of the sequences is discussed. 相似文献
958.
Harold J. C. Swan Peter T. Magnusson Neil A. Buchbinder Jack M. Matloff Richard J. Gray 《The Western journal of medicine》1978,128(1):26-34
Ventricular aneurysm is usually a complication of acute transmural myocardial infarction. The development of cardiac aneurysm represents a process of continued thinning and fibrosis of the necrotic tissue of the ventricular wall. Survival allows the development of a solid fibrous scar which of itself does not affect global ventricular function substantially. Hence, ventricular aneurysms can be present for up to 18 years without production of serious symptoms. The cases were reviewed of 45 patients in whom aneurysmectomy and myocardial revascularization were carried out. Surgical mortality was low (6.6 percent, 30 days); survival one year after operation was 76 percent, but at three years had fallen to 47 percent. Cause of late death was dominantly cardiac. In 19 patients post-operative study was done; although graft patency was observed in 98 percent, substantive improvement in ventricular performance was seen in a minority of patients. The outcome in patients with ventricular aneurysm is primarily related to the status of the residual myocardium and to the status of the vessels which supply it. The mechanism of clinical improvement after aneurysmectomy has not been clarified. However, the long-term results appear to be similar to those in patients with extensive myocardial infarction. 相似文献
959.
960.
Argun Saylam Joao Q. Melo Aftab Ahmad Richard D. Chapman James A. Wood Albert Starr 《The Western journal of medicine》1978,128(5):377-381
Embolectomy was carried out in eight patients with pulmonary emboli. Angiographic diagnosis was obtained in six, and in two cases pulmonary angiography could not be done because of the very critical condition of the patients. In the latter two, diagnosis was made based only on clinical findings. Two patients died in the operating room (25 percent). Six patients were discharged in good condition.It is emphasized that pulmonary embolectomy should be done in cases of pulmonary emboli when a clinical status of shock is present (systolic blood pressure less than 80 mm of mercury and the patient in low cardiac output syndrome) and when there is no response to medical treatment regardless of the degree of obstruction in the pulmonary arterial tree. 相似文献