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991.
A series of 1,8-naphthyridine derivatives variously substituted in the 2, 3, 4 and 7 positions were synthesized for in vitro evaluation of antimycobacterial activity in accordance with an international program with the tuberculosis antimicrobial acquisition and coordinating facility (TAACF). Several compounds 4, 8, 12, 14, 19, 29 and 30, when tested at a concentration of 6.25 microg/ml against Mycobacterium tuberculosis H37Rv, showed an interesting activity with % inhibition in the range 38-96%. The most effective substituent in position 2, 4 or 7 of the 1,8-naphthyridine nucleus seem to be the piperidinyl group.  相似文献   
992.
9,9-Dialkyloctahydropyrimido[3,4-a]-s-triazines were synthesized by iminodimethylation reaction between a 5,5-dialkyl-6-aminopyrimidine-2.4(3H,5H)-dione, a substituted aniline and two moles of formaldehyde. The synthesis of.5,5-dialkyl-6-aminopy-rimidinedione consisted of the condensation of urea with ethyl 2,2-dialkylcyanoacetates. 18 Octahydropyrimido[3,4-a]-s-triazines were synthesized and compounds resulting from a supplementary aminomethylation were also obtained. Most of these compounds were tested for antifungal activity in vitro. Only 9.9-dibutyl-6,8-dioxo-3(2-chlorophenyl)2,3,4,5,6,7,8,9-octahydropyrimido[3,4-a]-s-triazine showed some activity against Microsporum canis.  相似文献   
993.
2,3-Benzodiazepines represent a class of heterocyclic compounds that interact with AMPA-type glutamate receptors in a noncompetitive manner. These compounds have attracted great interest for their pharmacological effects against acute and chronic neurodegenerative diseases, such as ischemia and epilepsy. We synthesized a large number of 2,3-benzodiazepine derivatives, which showed anticonvulsant properties in different seizure models and a noncompetitive blockade of AMPA receptor. This article will briefly mention our work in this field and the main SAR considerations.  相似文献   
994.
995.
目的:研究重组L-门冬酰胺酶对肿瘤细胞体外生长及实验性肿瘤的抑制作用.方法:体外培养肿瘤细胞(K562、L1210和P815),分别用倒置显微镜和透射电镜观察肿瘤细胞的形态学,MTT比色法观察细胞增殖率及抑制率,流式细胞仪分析DNA含量.同时根据移植性肿瘤研究方法小鼠接种L1210、P388、Heps及S_(180)瘤株,观察给药后小鼠存活天数和瘤重.结果:体外细胞培养实验证明,重组L-门冬酰胺酶对K562、L1210和P815细胞生长具有显著抑制作用(P<0.01).体内实验表明,重组L-门冬酰胺酶ip能显著延长移植肿瘤小鼠(L1210和P388)的存活天数(P<0.01),并对小鼠移植性肝癌实体瘤(Heps)生长有明显的抑制作用(P<0.01)。重组L-门冬酰胺酶iv对小鼠Heps和S_(180)肿瘤生长有明显的抑制作用(P<0.01).结论:重组L-门冬酰胺酶对肿瘤细胞体外生长及受试肿瘤有明显抑制作用.本结果对重组L-门冬酰胺酶的临床应用提供实验依据.  相似文献   
996.
Tetrandrine(TET),a bis-benzylisoquinoline alkaloid purified and identified an active ingredient in a Chinese medicinal herb,Radix Stephanae tetrandrae,has been used traditionally for the treatment of congestive circulatory disorder and inflammatory diseases.TET,together with a few of its structural analogues,has long been demonstrated to have antihypertensive action in clinical as well as animal studies.Presumably,the primary anti-hypertensive action of TET is due to its vasodilatory properties.TET prevents or inhibits vascular contraction induced by membrane depolarization with KCl or α-adrenoceptor activation with phenylephrine (PE).TET(30μmol/L) also inhibits the release of endothelium-derived nitric oxide(NO) as well as NO production by inducible NO synthase.TET apparently inhibits multiple Ca^2 entry pathways as demonstrated in cell types lacking the L-type Ca^2 channels.In cardiac muscle cells,TET inhibits both L-and T-type Ca^2 channels.In addition to its actions on cardiovascular tissues,TET may also exert its anti-hypertensive action via a Ca^2 -dependent manner on other tissues intimately involved in the modulation of blood pressure control,such as adrenal grands.In adrenal glomerulosa cells,KCl-or angiotensin II-induced aldosterone synthesis is highly dependent on extracellular Ca^2 .Steroidogenesis and Ca^2 -influx in bovine adrenal glomerulosa cells have been shown to be potently inhibited by TET.In bovine adrenal chromaffin cells,TET inhibits Ca^2 currents via L-and N-type channels as well as other unidentified channels with IC50 of 10μmol/L.Other than the Ca^2 antagonistic effects.TET also interacts with the α-adrenergic receptors and muscarinic receptors based on functional as well as radioligand binding studies.Apart from its functional effects,TET and related compounds also exert effects on tissue structures,such as remodelling of hypertrophied heart and inhibition of angiogenesis,probably by causing apoptotic responses.TET is also known for its anti-inflammatory and anti-fibrogenic actions,which make TET and related compound potentially useful in the treatment of lung silicosis,liver cirrhosis,and rheumatoid arthritis.  相似文献   
997.
力达霉素对人肝癌BEL—7402细胞基因组DNA的影响   总被引:2,自引:0,他引:2  
目的:深入研究力达霉素对人肝癌BEL-7402细胞基因组DNA的影响。方法:琼脂糖凝胶电泳检测DNA泳带;Suthern杂交检测对基因的损伤;中性凝胶电泳检测DNA断裂修复;超螺旋GEM质粒检测断裂DNA位点。结果:力达霉素1μmol/L处理BEL-7402细胞,15,30,60min,可检测到明显的DNA梯带。低浓度的力达霉素对活跃基因N-ras的外显子和内含子均有明显的损伤作用,但对沉默IL-2基因没有影响。力达霉素断裂DNA后,DNA损伤难以修复。力达霉素断裂GEM质粒DNA的位点是-OH HO-。结论 :力达霉素明显地损伤人肝癌BEL-7402细胞的基因组DNA。该结果有助于解释其高活性地杀伤肿瘤细胞的分子机制。  相似文献   
998.
It has been suggested that early- and late-onset forms of obsessive-compulsive disorder (OCD) may stem from different neurobiological substrates manifesting themselves through particular phenotypic profiles. Our study aimed to assess the existence of clinical and therapeutic differences between adult patients with early- and late-onset OCD (EOCD and LOCD, respectively). Sixty-six patients with OCD were consecutively recruited among individuals seeking treatment in a university hospital clinic for anxiety and depressive disorders. Patients with EOCD (n=33) and LOCD (n=33) were compared and contrasted with regard to clinical and therapeutic characteristics using the two tailed t test for continuous variables and the Pearson's goodness of fit Chi-square test for categorical ones; Fisher's exact test was employed when indicated. We found that, compared to their LOCD counterparts, adult patients with EOCD were characterized by (1) male gender predominance, (2) greater number of clinically significant obsessions and compulsions, (3) higher frequency of rituals repetition, (4) increased severity of obsessive-compulsive symptoms at baseline, and (5) greater number of required therapeutic trials during the follow-up. However, no significant differences between groups were noted in the final treatment outcome. Our results are consistent with previous studies suggesting that EOCD may represent a more severe subtype of this disorder.  相似文献   
999.
To provide effective contraception and protection against sexually transmitted disease, vaginal gels should maximally cover the cervical os and the vaginal epithelium before, during and after intercourse. To non-invasively monitor the intravaginal distribution of an applied intravaginal gel, we performed high-resolution magnetic resonance imaging (MRI) of the female pelvis before, during and after both real and simulated sexual intercourse. We sought to determine whether simulated intercourse with a plastic phallus could be used as a surrogate for real intercourse for such experiments.

Dilute gadolinium chelate solution was mixed with Gynol-II gel and introduced intravaginally to volunteer female human subjects using a conventional applicator. MRI was performed at 1.5 Tesla with a surface coil. Imaging of the female pelvis was performed: (1) immediately after insertion of the gel; (2) during real intercourse with a male partner (2 subjects) or simulated intercourse with a plastic phallus (4 subjects); and (3) after completion of real or simulated intercourse. Subjects were studied after application of both 3 mL and 5 mL of vaginal gel. Measurements of gel thickness covering the vaginal mucosa were made digitally using electronic calipers.

The bolus of gel is initially located in the upper vaginal canal, superior to the urogenital diaphragm. Both real and simulated intercourse dramatically increases the spread of gel to the lower vagina. The cervix appears to be adequately covered with gel both before and after intercourse. Increasing the volume of the gel increases initial vaginal mucosal coverage but also increases leakage from the introitus. No statistically significant differences in vaginal mucosal coverage were found between patients having undergone real vs. simulated intercourse, or on post-intercourse scans of 3 mL versus 5 mL. MRI is a sensitive, reproducible means of tracking the spread of intravaginal medications.  相似文献   

1000.
BACKGROUND: Skin cancer is about as common as all other cancers combined and is preventable by sun protection. The most intense sun exposures often occur on the beach, so we chose this setting to test an intervention to affect sun protection behaviors. METHODS: We developed a multicomponent stage-matched intervention for beachgoers and evaluated its efficacy in a randomized trial for influencing stage of change and self-reported behavior. RESULTS: We randomized 2,324 persons ages 16 to 65 on the beach (83% of those approached). The intervention was effective in increasing self-reported sun protective behaviors. Effects were similar across gender and age groups. CONCLUSIONS; The beach is a good site for recruitment and intervention to prevent skin cancer in high-risk populations. Our stage-matched intervention package was effective for increasing sun protective behaviors.  相似文献   
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