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61.
Honda T Ota H Arai K Hayama M Fujimoto K Yamazaki Y Haniuda M 《Virchows Archiv : an international journal of pathology》2002,441(1):47-52
The etiology of usual interstitial pneumonia (UIP), a progressive lung disease, remains unclear. We examined alveolar structure in UIP three-dimensionally. Lung biopsy specimens from five patients with idiopathic pulmonary fibrosis were used. Sections 150-microm thick were stained with elastica solution for elastic fibers, with alpha-smooth muscle actin antibody for myofibroblasts, with anti-Thomsen-Friedenreich antibody for type-II pneumocytes and with anti-CD34 antibody for blood vessels. We examined them three-dimensionally using a laser confocal microscope or light microscope. In the fibrotic lesions, the thick elastic fibers forming the alveolar framework were not particularly dense considering the reduction in alveolar volume. Near the fibrotic lesions, some of the thin elastic fibers in the alveolar wall were slightly sinuous and ended with rounded tips. Type-II pneumocytes had proliferated and were distributed uniformly over the alveolar surface. Smooth muscle actin filaments were detected only around the alveolar orifice. These findings show that in UIP destruction of the elastic fiber framework of the alveoli may lead to irreversible focal alveolar collapse after damage to the alveolar epithelial cells, and proliferation of type-II pneumocytes may be involved with this elastolysis. 相似文献
62.
Jun-ichi Kadokawa Yoshitaka Matsumura Shiro Kobayashi 《Macromolecular chemistry and physics.》1994,195(11):3689-3698
This paper describes a new ring-opening-closing alternating copolymerization (ROCAC) of 2-methyl-2-oxazoline (five-membered cyclic imino ether, 1 ) with N-methyldiacrylamide ( 2 ). The reaction of a 1 : 1 monomer feed ratio proceeded without any added catalyst to give an alternating copolymer 3 having two structural units formed by ring-opening and ring-closing (cyclization). The structure of copolymer 3 was determined by 1H, 13C NMR, and IR spectroscopies. The extent of cyclization was at most 65%. The copolymerization was reasonably explained by a mechanism of propagation via zwitterion intermediates. 相似文献
63.
Nagai Y Fujikake N Ohno K Higashiyama H Popiel HA Rahadian J Yamaguchi M Strittmatter WJ Burke JR Toda T 《Human molecular genetics》2003,12(11):1253-1259
Polyglutamine (polyQ) diseases are a growing class of inherited neurodegenerative diseases including Huntington's disease, which are caused by abnormal expansions of the polyQ stretch in each unrelated disease protein. The expanded polyQ stretch is thought to confer toxic properties on the disease proteins through alteration of their conformation leading to pathogenic protein-protein interactions including oligomerization and/or aggregation. Hypothesizing that molecules with selective binding affinity to the expanded polyQ stretch may interfere with the pathogenic properties, we previously identified Polyglutamine Binding Peptide 1 (QBP1) from combinatorial peptide phage display libraries. We show here that a tandem repeat of the inhibitor peptide QBP1, (QBP1)(2), significantly suppresses polyQ aggregation and polyQ-induced neurodegeneration in the compound eye of Drosophila polyQ disease models, which express the expanded polyQ protein under the eye specific promoter. Most importantly, (QBP1)(2) expression dramatically rescues premature death of flies expressing the expanded polyQ protein in the nervous system, resulting in the dramatic increase of the median life span from 5.5 to 52 days. These results suggest that QBP1 can prevent polyQ-induced neurodegeneration in vivo. We propose that QBP1 prevents polyQ oligomerization and/or aggregation either by altering the toxic conformation of the expanded polyQ stretch, or by simply competing with the expanded polyQ stretches for binding to other expanded polyQ proteins. The peptide inhibitor QBP1 is a promising candidate with great potential as a therapeutic molecule against the currently untreatable polyQ diseases. 相似文献
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65.
Takashi Wakabayashi Michio Horiuchi Mikako Sakaguchi Hiroyuki Onda Moritake Iijimass 《Pathology international》1984,34(3):471-480
Propyl alcohol and butyl alcohol had similar effects to ethyl alcohol on ultrastructure of liver mitochondria. Rats were given 32% ethyl alcohol, 32% n-propyl alcohol, and 6.9% n-butyl alcohol in drinking water for up to three months. After one month, mitochondria in hepatocytes obtained from the experimental animals became elongated, constricted or cup-shaped with scanty cristae. After two months, mitochondria in some hepatocytes became gigantic. In extreme cases, the megamitochondria exceeded 10 μm in diameter. Coupling efficiencies of hepatic mitochondria obtained from alcohol-fed animals were well preserved despite their drastic morphologic changes. ACTA PATHOL. JPN. 34: 471–480, 1984. 相似文献
66.
A microsomal fraction was obtained from the zona glomerulosa of the bovine adrenal cortex. Glucose-6-phosphate activity of the fraction was found to be much lower than that of the liver. Contents of RNA and phospholipids, besides electron microscopic findings, of the fraction also indicate that it is rich in smooth-surfaced endoplasmic reticulum. Distribution of cytochrome P-450 in the zona glomerulosa was studied using various fractions including the microsomal fraction described above. The amount of cytochrome P-450 in mitochondria and that in microsomes were determined to be 0.73 and 0.32 nmoles/mg protein, respectively. The CO-difference spectrum was affected not only by the concentration of added deoxycholate but also by the incubation time after addition. Approximately 40-50% of cytochrome P-450 in the samples were converted to cytochrome P-420 within 20-30 seconds of incubation with deoxycholate. 相似文献
67.
68.
To determine if clinically observed disorders in heme biosynthetic enzymes, known as sporadic porphyria cutanea tarda (PCT), could be reproduced in experimental animals, male Fischer rats were treated with ethanol, estrogen and hexachlorobenzene (HCB). A series of heme biosynthetic enzymes were assayed. In the rats given free access to 8% ethanol-drinking water for 15 weeks, -aminolevulinate (ALA) dehydratase was significantly reduced in erythrocytes. In the liver, ALA synthetase and uroporphyrinogen (UROgen) decarboxylase activities remained unchanged. In bone marrow cells, these activities did not change markedly. In the rats treated with estrogen (1 mg estrioltripropionate /rat/week, IM), no body weight gain was observed during the treatment for 15 weeks and urinary ALA excretion increased to 1.7 fold over normal level. In the liver, a significant increase was observed in the activity of ALA dehydratase, but other enzymes remained within the normal level. In bone marrow cells and erythrocytes, ALA dehydratase was also increased. ALA synthetase increased only in bone marrow cells to 2.1 times higher than the control level. In rats fed 0.3% HCB-diet for 8 weeks, urinary excretion of ALA, coproporphyrin and uroporphyrin increased to 2.4, 3.3 and 3.8 times higher than the controls, respectively. In the liver, an increase was observed in ALA synthetase, while a decrease was observed in ALA dehydratase and UROgen decarboxylase. In bone marrow cells and erythrocytes, ALA dehydratase was reduced and activities of other enzymes did not show any changes.These results indicate that alcohol, estrogen and HCB do not produce phenomena similar to those observed clinically in PCT. 相似文献
69.
Fumie Takewaki Hanako Nakajima Daiki Takewaki Yoshitaka Hashimoto Saori Majima Hiroshi Okada Takafumi Senmaru Emi Ushigome Masahide Hamaguchi Masahiro Yamazaki Yoshiki Tanaka Shunji Nakajima Hiroshi Ohno Michiaki Fukui 《Nutrients》2021,13(6)
The aim of this research was to reveal the characteristics of gut microbiome altered by acarbose intervention in Japanese patients with type 2 diabetes (T2D) and its possible association with habitual dietary intake. Eighteen patients with T2D were administered acarbose for four weeks. The abundances of two major phyla, namely Actinobacteria and Bacteroidetes, were reciprocally changed accompanied by the acarbose intervention. There were also significant changes in the abundances of ten genera, including the greater abundance of Bifidobacterium, Eubacterium, and Lactobacillus and the lower abundance of Bacteroides in the group after the intervention than that before the intervention. Hierarchical clustering of habitual dietary intake was performed based on the pattern of changes in the gut microbiota and were classified into distinct three clusters. Cluster I consisted of sucrose, cluster II mainly included fat intake, and cluster III mainly included carbohydrate intake. Moreover, the amount of change in Faecalibacterium was positively correlated with the intake of rice, but negatively correlated with the intake of bread. The intake of potato was negatively correlated with the amount of change in Akkermansia and Subdoligranulum. Acarbose altered the composition of gut microbiome in Japanese patients with T2D, which might be linked to the habitual dietary intake. 相似文献
70.