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991.
目的 :通过测定妊高征 (PIH)患者红细胞免疫粘附 (RCIA)调节因子活性 ,探讨PIH患者红细胞免疫功能改变的原因。方法 :测定 40例PIH患者和 30例正常孕妇的RCIA促进因子活性和抑制因子活性及红细胞补体受体花环率(RBCC3bRR% )、红细胞免疫复合物花环率 (RBCICR % )。结果 :与正常孕妇相比 ,PIH患者RCIA抑制因子活性明显升高 ,RBCC3bRR%及RBCICR %明显降低 (P <0 .0 1) ,RCIA促进因子活性无明显变化 (P >0 .0 5 )。结论 :PIH患者红细胞免疫功能原发低下 ,其原因可能与RCIA抑制因子活性增高有关  相似文献   
992.
A female patient with a clinical picture of Turner's syndrome had five separate malignant tumors (three squamous cell carcinomas of the tongue, a colon cancer, and a glioblastoma multiforme). Her peripheral blood cells showed a 45,X/46,XXp-/46,XX/47,XXX mosaicism. The findings are discussed in relation to other extragonadal tumors in Turner's syndrome reported to-date.  相似文献   
993.
Effects of chemical mediators of anaphylaxis on ciliary function   总被引:2,自引:0,他引:2  
We assessed the effects of selected chemical mediators of anaphylaxis on CBF in vitro. Ciliated epithelial cells were obtained from the trachea of conscious sheep with a cytology brush and suspended in a perfusion chamber containing KH. Ciliary activity was viewed microscopically and recorded on videotape for subsequent slow-motion analysis of CBF. Prostaglandin E1 (10(-8) M to 10(-6) M), prostaglandin E2 (10(-10) M to 10(-6) M), and leukotriene-C4 (10(-8) M) increased CBF between 7% and 33%. Histamine caused ciliostimulation only at the relatively high concentrations above 10(-5) M (7% increase in CBF), whereas prostaglandin F2 alpha (10(-10) M and 10(-6) M) was without effect. In no preparation was ciliary discoordination observed. These findings indicate that several chemical mediators of anaphylaxis stimulate CBF and that the previously described impairment of mucociliary transport in stable allergic asthma or antigen-induced bronchoconstriction is probably not caused by a primary alteration of ciliary function.  相似文献   
994.
Total serum IgE levels were determined in 136 newborns and their mothers and in 54 of their fathers, using the paper radioimmunosorbent test (PRIST) technique. IgE specific antibodies for house dust (Dermatophagoides pteronyssinus), orchard grass, timothy grass, and cow's milk were measured with the radioallergosorbent test (RAST). One hundred thirty-three RAST assays were negative in newborns, and in three cases RAST for cow's milk was positive. Cord blood IgE ranged from 0 to 5.5 IU/ml (mean 0.32 ± 0.54 IU/ml); levels were significantly (p < 0.05) higher when maternal IgE was over 100 IU/ml and when mothers had received progesterone therapy during the pregnancy. Salbutamol administration or tobacco smoking during pregnancy did not influence newborn IgE. A clinical follow-up study was conducted in 83 infants for 9 mo. Nine infants developed definite atopic disease, and possible allergic diseases were noted in eight other infants. The IgE level at birth appeared to be more predictive for the development of allergy in infancy than the family history.  相似文献   
995.
Cytogenetic analysis using C-, G-, and Ag-nucleolus organizer region (NOR) staining techniques, performed on established cell lines as well as directly processed breast tumor effusions, revealed that: 1) chromosome No. 1 is involved in translocation; 2) based on 1q translocation chromosome, breast tumors could be classified into two groups; and 3) double minutes and homogeneously staining regions may be present in breast tumor cells in vivo as well as in vitro, and that homogeneously staining regions may exhibit some heterogeneity in staining.  相似文献   
996.
This report describes a new case of chronic myeloid leukemia with an unusual Philadelphia chromosome translocation involving chromosomes No. 4,9, and 22; t(4,9,22) (q31;q34;q11).  相似文献   
997.
998.
In order to assess the status of beta adrenergic receptors in bronchial asthma, binding studies using (−) [3H] dihydroalprenolol (DHA) were performed on lymphocytes of 10 control subjects and 11 stable asthmatic patients. Specific DHA binding was generally lower at all DHA concentrations in asthmatics. At 12 nM DHA concentration, specific DHA binding was 391 ± 40 fM/mg protein in controls and 263 ± 35 fM/mg protein for asthmatic subjects (p < 0.05). A highly statistically significant positive correlation between specific DHA binding (at 12 nM DHA) and FEV1/FVC% was observed (r = 0.93, p < 0.01), with those asthmatic subjects with the more severe airway obstruction and disease severity showing lower DHA binding. The results of the study suggest that a lymphocyte beta adrenergic receptor defect may be present among some patients with asthma. The magnitude of the receptor abnormality appears to be related to disease severity and degree of airway obstruction as measured by FEV1/FVC%. Documentation of drug consumption was made, and restriction of beta adrenergic agonists was attempted; theophylline and corticosteroids were the predominant drugs used in the study. Even with these precautions, it is possible that the differences in DHA binding observed among subjects are the results of greater drug (e.g., theophylline and corticosteroids) consumption by the clinically more severe patients. On the other hand, the lymphocyte receptor alteration noted may reflect a more general beta adrenergic receptor abnormality in bronchial asthma.  相似文献   
999.
A type C RNA virus was isolated from mink lung cell line (American Type Culture Collection No. CCL 64) which had been cocultivated with 5-bromodeoxyuridine (BUDR)-treated mouse spleen cells. The virus has type C RNA virus morphology as demonstrated by electron microscopy. The complement fixation and immunofluorescent tests performed with mouse anti-p30 antisera show a distinctive difference between mink and mouse type C viruses. Complement fixation tests also indicate that mink type C virus is antigenically different from rat, feline leukemia, feline endogenous (RD-114), baboon, and woolly monkey type C viruses. The virus propagates in cells of mouse, rat, cat, sheep, dog, and human origin, but not in bovine (MDBK) or simian (BSC-1) cells. The infection of rabbit (SIRC) cells and cells of virus origin (mink lung) was followed by delayed and low-titer polymerase release in tissue culture media. The virus sediments in sucrose density gradients as a broad band of densities, 1.13–1.17 g/ml, and contains 70 and 4S RNA. The protein profile is similar to that observed in other mammalian type C viruses. The DNA complementary to the poly(A)-containing virion RNA hybridized to a high degree (72%) with the RNA from virus-producing mink lung cells but not with the RNA from mouse cell lines or uninfected mink lung cell line. The nucleotide sequences homologous to mink viral cDNA were found in mink cell DNA from both virus-producing and nonproducing cells, but not in the DNA of mouse, rat, or feline origin. The virus here described therefore represents an endogenous mink type C virus.  相似文献   
1000.
Summary After prelabeling the adenine nucleotides (ATP, ADP, AMP) of isolated perfused guinea pig hearts with either14C-adenine or14C-adenosine for 35 min, labeled adenosine, inosine, hypoxanthine and cyclic 35-AMP (cAMP) were continuously released into the cardiac perfusate. Determination of the specific activities (SA) of the adenine nucleotides, cAMP, and their breakdown products (adenosine, inosine, hypoxanthine) in tissue and perfusate revealed: Under steady state conditions the SA of adenosine and cAMP in the perfusate were of the same order of magnitude and proved to be many times higher than the SA of the respective precursor adenine nucleotides. This difference was observed regardless whether adenine or adenosine was used as prelabeling substance. The SA of inosine and hypoxanthine in the perfusate were constantly lower than the SA of adenosine. Cardiac ischemia of 6 min, which resulted in a markedly increased formation of adenosine, led to a pronounced decrease in the SA of adenosine released from the heart.Our findings provide evidence that at least two different adenine nucleotide compartments of the heart serve as precursors for the formation of adenosine and cAMP, one characterized by a high, the other by a lower SA. Under normoxic conditions adenosine and cAMP released into the cardiac perfusate are derived mainly from a nucleotide fraction of high SA, which appears to be rather small. During ischemia a second compartment of much lower SA in addition contributes to the formation of adenosine.A preliminary report of part of this work appeared in Biochemistry and Pharmacology of Myocardial Hypertrophy, Hypoxia and Infarction Vol. 7 of Recent advances in studies on cardiac structure and metabolism. (P. Harris, R. J. Bing, A. Fleckenstein, eds.), pp. 171–175. München: Urban & Schwarzenberg 1976A preliminary report of part of this work appeared in Biochemistry and Pharmacology of Myocardial Hypertrophy, Hypoxia and Infarction Vol. 7 of Recent advances in studies on cardiac structure and metabolism. (P. Harris, R. J. Bing, A. Fleckenstein, eds.), pp. 171–175. München: Urban & Schwarzenberg 1976  相似文献   
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