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601.
602.
B-lymphocytic hairy cells contain no HTLV-II DNA sequences 总被引:1,自引:0,他引:1
HTLV-II has been found in some cases of the rare T-cell form of hairy- cell leukemia (HCL) and in a leukopenic chronic T-cell leukemia mimicking HCL. We asked whether the virus is implicated in the more frequent B-cell form of HCL. DNA extracted from the mononuclear cells derived from spleen (eight cases) or peripheral blood (eight cases) of 16 patients with the B-cell form of HCL was probed. No viral sequences were detected at levels of sensitivity as low as one viral genome in five cells. Therefore HTLV-II may not be involved in the B-cell form of HCL. 相似文献
603.
604.
Metabolism of carcinogenic heterocyclic and aromatic amines by recombinant human cytochrome P450 enzymes 总被引:10,自引:4,他引:6
Hammons GJ; Milton D; Stepps K; Guengerich FP; Tukey RH; Kadlubar FF 《Carcinogenesis》1997,18(4):851-854
The N-hydroxylation of carcinogenic arylamines represents an initial step
in their metabolic activation. Animal studies have shown that this reaction
is catalyzed by the cytochrome P450 (P450) enzymes P450 1A1 and P450 1A2.
In this study, utilizing enzymes expressed in Escherichia coli (and
purified) or in human B-lymphoblastoid cells, the catalytic activities of
recombinant human P450 1A1, P450 1A2, and P450 3A4 for N- hydroxylation of
several carcinogenic arylamines were determined. P450 1A2 from both
expression systems catalyzed the N-hydroxylation of 4- aminobiphenyl and
the heterocyclic amines, 2-amino-3-methylimidazo[4,5- f/quinoline (IQ),
2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and
2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Rates were similar,
with values of 1.1-7.8 nmol/min/nmol P450. In contrast, P450 1A1 catalyzed
N-hydroxylation of only PhIP, and no activity was observed with P450 3A4.
Further kinetic analysis with purified P450 1A2 showed similar Km and Vmax
values for N-hydroxylation of the arylamines. Furafylline and fluvoxamine,
inhibitors of P450 1A2 activity in human liver microsomes, were found to be
inhibitory of the recombinant P450 1A2 N-hydroxylation activity. Results
from this study are supportive of a major role for human P450 1A2 in the
metabolic activation of arylamines.
相似文献
605.
Johnson P. Hampson Barbara D. Reed Daniel J. Clauw Rupal Bhavsar Richard H. Gracely Hope K. Haefner Richard E. Harris 《The journal of pain》2013,14(6):579-589
Vulvodynia (VVD) is a chronic pain disorder wherein women display sensitivity to evoked stimuli at the vulva and/or spontaneous vulvar pain. Our previous work suggests generalized hyperalgesia in this population; however, little is known about central neurobiological factors that may influence pain in VVD. Here we investigated local (vulvar) and remote (thumb) pressure-evoked pain processing in 24 VVD patients compared to 13 age-matched, pain-free healthy controls (HCs). As a positive control we also examined thumb pressure pain in 24 fibromyalgia patients. The VVD and fibromyalgia patients displayed overlapping insular brain activations that were greater than HCs in response to thumb stimulation (P < .005 corrected). Compared to HCs, VVD participants displayed greater levels of activation during thumb stimulation within the insula, dorsal midcingulate, posterior cingulate, and thalamus (P < .005 corrected). Significant differences between VVD subgroups (primary versus secondary and provoked versus unprovoked) were seen within the posterior cingulate with thumb stimulation and within the precuneus region with vulvar stimulation (provoked versus unprovoked only). The augmented brain activation in VVD patients in response to a stimulus remote from the vulva suggests central neural pathology in this disorder. Moreover, differing central activity between VVD subgroups suggests heterogeneous pathologies within this diagnosis.PerspectiveThe presence of augmented brain responses to pressure stimuli remote from the vulva was observed in vulvodynia patients. These findings may guide treatment decisions for better response, as brain mechanisms may be a factor in some VVD patients. 相似文献
606.
The clinical records and radiographs of 45 patients who had undergone replantation of a total hand, or a part thereof, were reviewed in order to determine the prevalence and the type of articular changes occurring distal to the site of anastomoses. In three patients, destructive joint changes were observed, consisting of bony fragmentation, spiculation, and cystic or erosive lesions. These changes, which developed between five and ten months after replantation, are most likely neuropathic or osteonecrotic in pathogenesis. 相似文献
607.
Cholangiocarcinoma complicating primary sclerosing cholangitis: cholangiographic appearances 总被引:1,自引:0,他引:1
MacCarty RL; LaRusso NF; May GR; Bender CE; Wiesner RH; King JE; Coffey RJ 《Radiology》1985,156(1):43-46
Cholangiograms from 104 patients (and serial cholangiograms in 66 patients) with primary sclerosing cholangitis (PSC) were reviewed. In 13 patients the additional diagnosis of cholangiocarcinoma was made at biopsy or autopsy. Cholangiograms from patients with both PSC and carcinoma were compared with cholangiograms from patients with PSC alone. Marked dilatation of ducts or ductal segments (100% vs. 24%) and the appearance of a polypoid mass (46% vs. 7%) were common findings in the group of patients whose disease was complicated by malignancy. In the malignant group, polypoid masses were larger, measuring 1 cm or greater in diameter. On serial cholangiograms, four of 15 patients with progressive stricture formation and four of five with progressive ductal dilatation proved to have carcinomas. The frequent occurrence of bile duct carcinoma as a complication of PSC in this group of patients indicates that PSC has a strong tendency to undergo malignant degeneration. Cholangiographic findings which suggest malignant degeneration include markedly dilated ducts or ductal segments, presence of a polypoid mass 1 cm or greater in diameter, and progressive stricture formation or ductal dilatation. 相似文献
608.
609.
Desipramine relieves postherpetic neuralgia 总被引:11,自引:0,他引:11
R Kishore-Kumar M B Max S C Schafer A M Gaughan B Smoller R H Gracely R Dubner 《Clinical pharmacology and therapeutics》1990,47(3):305-312
Desipramine has the least anticholinergic and sedative effects of the first generation tricyclic antidepressant agents, but its pain-relieving potential has received little study. Other antidepressant agents--notably amitriptyline--are known to ameliorate postherpetic neuralgia, but those agents are often toxic. In a randomized double-blind crossover design, we gave 26 postherpetic neuralgia patients 6 weeks of treatment with desipramine (mean dose, 167 mg/day) and placebo. Nineteen patients completed both treatments; 12 reported at least moderate relief with desipramine and two reported relief with placebo. Pain relief with desipramine was statistically significant from weeks 3 to 6. Psychiatric interview at entry into the study produced a diagnosis of depression for 4 patients; pain relief was similar in depressed and nondepressed patients and was statistically significant in the nondepressed group alone. We conclude that desipramine administration relieves postherpetic neuralgia and that pain relief is not mediated by mood elevation. Blockade of norepinephrine reuptake, an action shared by desipramine, amitriptyline, and other antidepressant agents that have relieved neuropathic pain, may be involved in relief of postherpetic neuralgia. 相似文献
610.