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Benign neonatal seizures 总被引:3,自引:0,他引:3
Benign neonatal seizures is a rare but increasingly recognized syndrome characterized by seizures in the neonatal or infantile period. Two forms are recognized: familial and nonfamilial. In both instances, the seizures may be quite severe, and status epilepticus is common. The nonfamilial form is characterized by idiopathic, self-limited seizures occurring in previously normal neonates. The seizures most commonly occur at day 5 and have been called "fifth-day fits" by some authors. Familial seizures most frequently have their onset during the first week of life, but onset may occur as late as early infancy. These seizures may recur for several months before resolving. No cause is found for the seizures, and the patient appears healthy during the interictal period. The family history reveals benign neonatal seizures in other family members. Although the prognosis is favorable in both syndromes, seizures may occasionally occur later in life in the familial form. The familial form of benign neonatal seizures is autosomal dominant, and the gene has been localized to chromosome 20. 相似文献
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Holmes A 《The Journal of American health policy》1994,4(1):41-45
What premiums states pay under community rating will be determined by how much they spend on health care. But it's not clear how spending is affected by prices, utilization, disease rates, and behavior. The answers will test Americans' commitment to one another. 相似文献
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By nearly any standard--federal research dollars, faculty credentials, and student career plans--the medical schools of East Carolina University and Johns Hopkins are as different as day and night. But both agree that Washington's efforts to boost the number of generalist physicians are inadequate. 相似文献
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Deoxyspergualin, a synthetic analogue of the immunosuppressive anti-tumour antibiotic spergualin, has been shown to possess potent in vitro and in vivo antitumour activity and is currently in the National Cancer Institute (NCI) decision network. Deoxyspergualin shows similarities in properties and mechanisms of action to the natural-product immunosuppressive agents cyclosporin A and FK506, each of which can act as a modifier of multi-drug resistance. We therefore decided to examine the comparative activity of deoxyspergualin in parent and multidrug-resistant cells. Deoxyspergualin contains the polyamine spermidine within its structure. Bovine serum copper amine oxidase catalyses the oxidative deamination of spermidine to produce an aminoaldehyde, ammonia and hydrogen peroxide. These aminoaldehydes are believed to be responsible for the toxicity of polyamines in vitro in the presence of bovine serum. For this reason, all experiments were carried out in medium containing bovine serum and in medium containing horse serum (which is low in copper amine oxidase content). We used the tetrazolium (MTT) colorimetric assay to determine drug sensitivity and tritiated daunorubicin accumulation together with inhibition of azidopine binding to study specific mechanisms of resistance modulation. The murine cell lines EMT6/P and EMT6/AR1.0 and the human cell lines H69/P and H69/LX4 were, respectively, 32-, 32-, 372- and 483-fold more sensitive to spermidine and 175-, 133-, 321- and 444-fold more sensitive to spermine in the presence of calf serum than in the presence of horse serum. However, these large differential effects were not seen for deoxyspergualin. It appears that in the presence of horse serum, deoxyspergualin may exert its effect by a mechanism other than polyamine oxidation. Deoxyspergualin did not enhance the accumulation of [3H]-daunorubicin in EMT6/AR1.0 cells. Furthermore, deoxyspergualin (1–20 M) did not restore the sensitivity of EMT6/AR1.0 or H69/LX4 cells to that of the parent lines. P-glycoprotein (Pgp) in membranes prepared from H69/LX4 cells was photo-affinity-labeled with [3H]-azidopine. Deoxyspergualin did not inhibit this labeling. Although deoxyspergualin appears to exert its immunosuppressive effect via a mechanism similar to that of cyclosporin A and FK506, it does not share their ability to modify Pgp-mediated multidrug resistance. However, its lack of cross-resistance and potent in vivo anti-tumour activity make deoxyspergualin a promising candidate for development as an anti-cancer agent. 相似文献
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Karen Hoffman Frankie Ann Holmes Giuseppe Fraschini Laura Esparza Debra Frye Martin N. Raber Robert A. Newman Gabriel N. Hortobagyi 《Cancer chemotherapy and pharmacology》1995,37(3):254-258
Triciribine is a purine analogue which inhibits DNA and protein synthesis. We performed two studies to define its activity against metastatic breast cancer. The first study was a phase II study in 14 patients with metastatic breast cancer who had received two or fewer chemotherapy treatments. The treatment schedule was triciribine 20 mg/m2 per day by 24-h infusion (CI) daily for 5 days every 6 weeks as recommended by a previous open phase I trial. When neither response nor toxicity was seen in the phase II trial, we assumed the starting dose was too low for this group of patients with good performance status and repeated the phase I trial in patients with metastatic breast cancer with good performance status. The starting dose was 35 mg/m2 per day using the same 5-day CI schedule, and starting doses were increased in subsequent cohorts of three patients in increments of 5 mg/m2 until toxicity occurred. In the initial (phase II) study, one patient had stable disease for 18 weeks (three courses), the remainder progressed. There were no significant toxic effects. In the subsequent phase I study, ten patients were treated until the study was closed The maximum dose was 40 mg/m2. Two patients died, one each at the 35 and 40 mg/m2 levels, respectively, 3 months and 6 weeks after their last course, one without interveing disease progression. Both had severe hypertriglyceridemia (18- and 21-fold elevation) and severe fatigue. At postmortem examination, one had congestive cardiomyopathy, and the other had severe pancreatitis and hypothyroidism. One patient had severe exacerbation of psoriasis which made her bedridden for more than 30 days. Four patients had hyperglycemia. Plasma pharmacology studies showed erratic drug levels, presumably related to enterohepatic circulation. Postmortem pharmacology studies showed residual drug present as long as 12 weeks after the last dose. We conclude that triciribine is ineffective at all doses tested and at doses of 35 mg/m2 has unacceptable toxic effects.This work was performed under National Cancer Institute contract 1-CM-57739 相似文献