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111.
ObjectivesThe last Canadian biobehavioural surveillance study of HIV and other sexually transmitted and blood-borne infections (STBBI) among gay, bisexual and other men who have sex with men (GBM) was conducted in 2010. We designed a study to measure STBBI prevalence among GBM in metropolitan Montreal, Toronto and Vancouver and to document related preventive and risk behaviours.MethodsThe Engage Cohort Study used respondent-driven sampling (RDS) to recruit GBM who reported sex with another man in the past 6 months. At baseline, we examined recruitment characteristics of the samples, and the RDS-II-adjusted distributions of socio-demographics, laboratory-confirmed HIV and other STBBI prevalence, and related behaviours, with a focus on univariate differences among cities.ResultsA total of 2449 GBM were recruited from February 2017 to August 2019. HIV prevalence was lower in Montreal (14.2%) than in Toronto (22.2%) or Vancouver (20.4%). History of syphilis infection was similar across cities (14–16%). Vancouver had more HIV-negative/unknown participants who reported never being HIV tested (18.6%) than Toronto (12.9%) or Montreal (11.5%). Both Montreal (74.9%) and Vancouver (78.8%) had higher proportions of men who tested for another STBBI in the past 6 months than Toronto (67.4%). Vancouver had a higher proportion of men who used pre-exposure prophylaxis (PrEP) in the past 6 months (18.9%) than Toronto (11.1%) or Montreal (9.6%).ConclusionThe three largest cities of Canada differed in HIV prevalence, STBBI testing and PrEP use among GBM. Our findings also suggest the need for scale-up of both PrEP and STI testing among GBM in Canada.  相似文献   
112.
BACKGROUND: Chinese herbal medicine has a long history of human use. A novel herbal formula, anti-asthma herbal medicine intervention (ASHMI), has been shown to be an effective therapy in a murine model of allergic asthma. OBJECTIVE: This study was undertaken to compare the efficacy, safety, and immunomodulatory effects of ASHMI treatment in patients with moderate-severe, persistent asthma with prednisone therapy. METHODS: In a double-blind trial, 91 subjects underwent randomization. Forty-five subjects received oral ASHMI capsules and prednisone placebo tablets (ASHMI group) and 46 subjects received oral prednisone tablets and ASHMI placebo capsules (prednisone group) for 4 weeks. Spirometry measurements; symptom scores; side effects; and serum cortisol, cytokine, and IgE levels were evaluated before and after treatment. RESULTS: Posttreatment lung function was significantly improved in both groups as shown by increased FEV(1) and peak expiratory flow findings (P<.001). The improvement was slightly but significantly greater in the prednisone group (P<.05). Clinical symptom scores, use of beta(2)-bronchodilators, and serum IgE levels were reduced significantly, and to a similar degree in both groups (P<.001). T(H)2 cytokine levels were significantly reduced in both treated groups (P<.001) and were lower in the prednisone-treated group (P<.05). Serum IFN-gamma and cortisol levels were significantly decreased in the prednisone group (P<.001) but significantly increased in the ASHMI group (P<.001). No severe side effects were observed in either group. CONCLUSION: Anti-asthma herbal medicine intervention appears to be a safe and effective alternative medicine for treating asthma. In contrast with prednisone, ASHMI had no adverse effect on adrenal function and had a beneficial effect on T(H)1 and T(H)2 balance.  相似文献   
113.
Kim YH  Min SJ  Ko MH  Park JW  Jang SH  Lee PK 《Neuroscience letters》2005,382(3):280-285
Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) could modulate the visuospatial functions. In this study, we investigated the effect of off-line high frequency subthreshold rTMS, when applied over the right or left posterior parietal cortex (PPC), on the visuospatial attention of the bilateral hemispaces. The subjects underwent visuospatial tasks before and immediately after receiving 1000 pulses of 10 Hz rTMS for a period of 20 min, and their responses were recorded. Our results demonstrated that the high frequency rTMS applied over the PPC produced facilitative effects on the visuospatial attention to the contralateral hemispace. The inhibitory effect to the ipsilateral hemispace was noticeable only in the left PPC.  相似文献   
114.
115.
Since previous studies have suggested that the coupling of oxidation to phosphorylation is impaired in Alzheimer brain and fibroblasts, the effects of carbonyl cyanide m-chlorophenylhydrazone, a hydrazone known to uncouple mitochondrial oxidative phosphorylation, were tested on the development of immunoreactivity with antibodies to "Alzheimer antigens" in cultured fibroblasts from cognitively intact subjects. The fibroblasts were exposed for 10 to 14 days to a medium (DMd) modeled on media that favor neuronal differentiation in fetal brain cultures. The addition of a 10-microns concentration of carbonyl cyanide m-chlorophenylhydrazone to the DMd culture medium increased by more than 10-fold the proportion of cells reacting immunocytochemically with antibodies to paired helical filaments and by 157-fold the proportion of cells reacting with the Alz-50 monoclonal antibody. These observations suggest that the oxidative abnormalities previously described in tissues from patients with Alzheimer's disease may contribute to the accumulation of abnormal cytoskeletal materials in this disorder.  相似文献   
116.
Liver microsomal epoxide hydrolase (mEH) is active in the detoxificationof epoxide-containing carcinogens. The effects of thiazole andpyrazine, constituents of tobacco and tobacco smoke as wellas of a variety of foods, on the expression and regulation ofmEH were examined in rats (200 mg/kg body wt/day, i.p., 1/emdash3 days). Immunoblot analyses using rabbit anti-rat mEH antibodyrevealed a significant increase in mEH levels in hepatic microsomesisolated from either thiazole- or pyrazine-treated animals.Another protein (43 kd) cross-reacting with polyclonal mEH antibodywas found to be increased concomitantly following pyrazine treatment.Northern and slot blot analyses showed substantial increasesin mEH mRNA following either thiazole or pyrazine treatment.The level of mEH mRNA increased 17-fold at 24 h following thiazoletreatment, relative to control. Approximately 20- and 16-foldincreases in mEH mRNA were also observed at 48 and 72 h respectivelyfollowing treatment with pyrazine. The level of polymerase chainreaction (PCR)-amplified mEH DNA derived from poly(A)+ RNA wasclearly elevated following either thiazole or pyrazine treatmentrelative to that from untreated animals. Both sense and antisensestrands of PCR-amplified mEH DNA were cloned into an M13mpl9phage vector in order to examine the nucleotide sequences ofPCR-amplified mEH DNA derived from the poly(A)+ RNA isolatedfrom thiazole- or pyrazine-treated animals. Sequence analysesrevealed that the sequence of PCR-amplified DNA from the inducedmRNA was identical to that published for mEH cDNA. Epoxide hydrolaseactivity toward the hydrolysis of 2-cyanoethylene oxide (CEO),the epoxide metabolite of the rat carcinogen acrylonitrile,was not significant in hepatic microsomes from untreated rats,but was substantially induced by treatment with thiazole orpyrazine. Microsomal hydrolysis activity was heat-sensitiveand potently inhibited by l, l, l-trichloropropene-2, 3-oxide,indicating that mEH was the catalyst. The Vmax for the hydrolysisof CEO by hepatic microsomes from thiazole-treated rats (13.4nmol/min/mg protein) was 1.5-fold greater than that with microsomesfrom pyrazine-treated rats, whereas similar Km values ( 1 mM)were observed for both microsomal preparations. These kineticdata correlate well with the increases in mEH mRNA observedafter administration of thiazole or pyrazine to rats. Theseresults provide evidence that administration of thiazole orpyrazine induces mEH with a large increase in mEH mRNA, andthat the induced mEH catalyzes the hydrolysis of CEO.  相似文献   
117.
Disability of children is an urgent, little investigated and medicosocial problem. It is characterised by high level, severity, very slow dynamics and stipulates the formation of population of "invalids from childhood" among adult population. The main causes of disability are congenital and genetic diseases, mainly neuropsychic. Hereditary factors, diseases during pregnancy, the use of drugs, consumption of alcohol, complicated delivery also play a major role. The lack of watchfulness both on the part of physicians and the parents themselves also results in the birth of affected children. Prevention priorities include medico-genetic counseling, the improvement of obstetric care and increasing awareness of the importance of family planning among young people. The disability of children should be regarded as an important qualitative indicator of joint activities of obstetrician-gynaecologists, general practitioners and pediatricians.  相似文献   
118.
蝶窦囊肿诊治47例分析   总被引:5,自引:1,他引:4  
目的:提高对蝶窦囊肿的认识,以利于其诊断和治疗,方法:回顾性分析蝶窦囊肿47例,总结其发病趋势、临床表现,影像学特征及治疗效果。结果:蝶窦囊肿最主要的临床症状为头痛,约占64%;其次为眼部症状,再次为鼻部症状。蝶窦囊肿最易易及视神经,影响者视力,早期手术有利于神经力的恢复。鼻内窥镜下蝶窦囊肿摘除了术有损伤小,出血少,痛苦轻,手术时间短、安全,术后恢复快等优点。结论:CT、MRI和鼻内窥镜的应用,提  相似文献   
119.
Anthocyanins belong to the flavonoid family and are ubiquitous in plants, especially in flower petals and fruit peels. We established that anthocyanins isolated from fruits of Aronia melanocarpa markedly inhibited the mutagenic activity of benzo(a)pyrene and 2-amino fluorene in the Ames test. In the Sister Chromatid Exchanges (SCEs) test with human blood-derived lymphocytes cultured in vitro, a significant decrease of SCEs frequency induced by benzo(a)pyrene was observed in the presence of anthocyanins. In the case of mitomycin C the effect of anthocyanins on SCEs frequency was smaller but still noticeable. Anthocyanins markedly inhibited the generation and release of superoxide radicals by human granulocytes. The results suggest that the antimutagenic influence of anthocyanins is exerted mainly by their free-radicals scavenging action as well as by the inhibition of enzymes activating promutagens and converting mutagens to the DNA-reacting derivatives. These preliminary data seem to be important in the aspect of a possible antimutagenic and anticarcinogenic potency of anthocyanins commonly present in fruits and vegetables.  相似文献   
120.
  1. High potassium produced a concentration-dependent contraction in rat isolated spleen.
  2. The high potassium-induced contraction of rat spleen was abolished in Ca2+-free Krebs solution containing 1 mM EGTA, and the subsequent addition of 3 mM Ca2+ restored the high potassium-induced contraction to the control level.
  3. Nifedipine, verapamil, diltiazem, Cd2+, Ni2+, Co2+, R-(+)-Bay K 8644 and pimozide inhibited and relaxed high potassium-induced contraction of rat spleen with IC50 and EC50 values much higher than those values in rat aorta.
  4. In addition, high potassium-stimulated contraction of rat spleen was insensitive to ω-conotoxin GVIA, ω-conotoxin MVIIC and ω-agatoxin IVA.
  5. The high potassium-induced contraction of rat spleen was also unaffected by tetrodotoxin (TTX), prazosin, chloroethylclonidine (CEC), yohimbine, propranolol, atropine, diphenhydramine, cimetidine, ketanserin, 3-tropanyl-indole-3-carboxylate, saralasin, indomethacin, nordihydroguaiaretic acid, GR32191B, domperidone, naloxone, chlorpromazine, suramin, (±)-2-amino-5-phosphonopentanoic acid, 6,7-dinitroquinoxaline-2,3-dione (DNQX), L-659,877, L-703,606, lorglumide, PD 135,158 N-methyl-D-glucamine, benextramine, amiloride, dantrolene, TMB-8, econazole, staurosporine and neomycin.
  6. Forskolin and sodium nitroprusside relaxed high potassium-induced contraction of rat spleen with EC50 values of 0.55±0.04 and 20.0±2.7 μM, respectively.
  7. It is concluded that high potassium may activate a novel, pharmacologically uncharacterized voltage-operated Ca2+ channel in rat spleen.
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