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51.
52.
DC Wilson MJ Cunningham MMcC Reid SS Johnston TF Fannin 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(1):84-85
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis. 相似文献
53.
54.
Katzman MA Struzik L Vijay N Coonerty-Femiano A Mahamed S Duffin J 《Psychiatry research》2002,113(1-2):181-192
Klein (Arch Gen Psychiatry, 50, 1993, 306-317) has suggested that panic disorder patients have a false suffocation alarm that may be associated with a lowered threshold for carbon dioxide detection. We compared the thresholds and sensitivities of the central and peripheral chemoreflexes between panic disorder patients and age- and sex-matched healthy volunteers to test this aspect of the hypothesis. We used a modified version of Read's rebreathing technique in 11 panic disorder patients and 10 healthy volunteers to examine the peripheral and central chemoreflex characteristics in these two populations. Subjects were examined during three rebreathing tests: training, hyperoxic (central chemoreflex alone) and hypoxic (combined central and peripheral chemoreflex). Panic symptoms were retrospectively assessed between groups using a DSM-IV derived Panic Symptom Scale. Comparisons of panic disorder patients with agoraphobia and healthy volunteers showed no significant differences in sensitivities or thresholds. Klein's hypothesis is not supported by these data. If a false suffocation alarm exists, its triggering may not be implemented within the respiratory chemoreflexes. 相似文献
55.
Loss of tumor-promoting activity of unleaded gasoline in N- nitrosodiethylamine-initiated ovariectomized B6C3F1 mouse liver 总被引:1,自引:0,他引:1
Unleaded gasoline (UG) vapor (2056 ppm) increased the incidence of liver
tumors in a chronic bioassay and exhibited tumor-promoting activity in
N-nitrosodiethylamine (DEN)-initiated female mouse liver. Estrogen
inhibited mouse liver tumor development and the hepatocarcinogenic and
tumor-promoting dose of UG produced uterine changes suggestive of estrogen
antagonism. To directly test the hypothesis that UG-induced tumor-promoting
ability is secondary to its interaction with the mouse liver tumor
inhibitor, estrogen, we compared the tumor-promoting ability of UG in
ovariectomized (Ovex) mice with the hepatic tumor-promoting ability of UG
in intact mice. Ovaries were surgically removed at 4 weeks of age. Exposure
to wholly vaporized UG (2018 ppm) under bioassay and tumor-promoting
conditions began at 8 weeks of age. After 4 months of exposure, UG
increased relative liver weight and hepatic microsomal cytochrome P450
pentoxyresourfin-O- dealkylase and ethoxyresorufin-O-deethylase activity to
a similar extent in intact and Ovex mice. Non-focal hepatocyte
proliferation, as measured by the incorporation of bromo-deoxyuridine, was
not changed by UG exposure and was similar in all treatment groups. After 4
months of exposure to DEN-initiated mice, UG significantly increased the
volume fraction of liver occupied by foci (three-fold) as compared to
control intact mice. As expected, volume of foci was elevated in
DEN/Ovex/control mice as compared to DEN/intact/control mice. In DEN/Ovex
mice UG did not significantly increase the focal volume fraction. Thus, the
tumor promoting activity of UG, as demonstrated by increased volume
fraction of liver occupied by hepatic foci in intact mice, is greatly
attenuated in Ovex mice. The volume fraction data in Ovex mice support the
hypothesis that the tumor promoting activity of UG is dependent upon the
interaction of UG with ovarian hormones. These data also indicate that
hepatic microsomal cytochrome P450 PROD and EROD induction, hepatomegaly
and non-focal hepatic LI are not specific markers of hepatic tumor
promoting activity of UG.
相似文献
56.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
相似文献
57.
Wu DC; Liu JM; Chen YM; Yang S; Liu SM; Chen LT; Whang-Peng J 《Japanese journal of clinical oncology》1997,27(2):115-118
Hemolytic uremic syndrome spontaneously arises in a few patients with
advanced cancer, but it is more commonly related to the use of certain
chemotherapeutic agents. Mitomycin-C is, etiologically, the most common
causative agent inducing hemolytic uremic syndrome, in a dose dependent
manner. We report this syndrome, attributable to mitomycin-C at a
cumulative dose of 40 mg/m2, in a gastric cancer patient. A 42-year-old
female with stage III gastric cancer underwent radical gastrectomy and was
given mitomycin-C at 10 mg/m2 intravenously every four weeks as adjuvant
therapy. Hemolytic uremic syndrome was diagnosed three months after the
last dose of mitomycin-C administration. The most prominent symptoms
included pallor, hypertension and anasarca, with laboratory evidence of
microangiopathic hemolytic anemia, azotemia and hyperkalemia. Her disease
was progressive, but fortunately stabilized after staphylococcus column A
dialysis. Her disease remained in remission for 24 months from the time of
diagnosis, and then relapsed in the form of peritoneal carcinomatosis with
partial intestinal obstruction.
相似文献
58.
The brain stem of anesthetized cats was explored with two microelectrodes in the region of the nucleus retroambigualis group of respiratory neurons. A total of 36 simultaneously recorded pairs of neurons was obtained: 30 inspiratory pairs, 5 expiratory pairs, and 1 mixed pair. The detailed firing patterns of these pairs of neurons were analyzed for functional connectivity using the technique of cross-correlation. The small percentage (10%) of inspiratory pairs showing positive cross-correlation led to the conclusion that there are few strong correlations among inspiratory neurons in the region of the nucleus retroambigualis. 相似文献
59.
A new series of mono- and di-hydroxy substituted naphthalene compounds was synthesized and found to possess antimalarial activity against P. gallinaceum infection of young chicks. A representative compound with a high degree of activity was chosen for extensive testing against other malarial species and for pharmacological investigation. The formula of this compound, number 377C54, was 1:6-dihydroxy-2:5-bis(cyclohexylaminomethyl)naphthalene dihydrochloride. Effective doses against P. gallinaceum in chicks, P. berghei in mice and P. cathemerium in canaries were 2.3, 4.0, and about 6 mg./kg. respectively. Compound 377C54 acted rapidly against the parasitaemia of P. gallinaceum in chicks and P. knowlesi in a rhesus monkey. Parasiticidal activity remained in the blood of chicks for a long time after a single oral dose. The drug can be estimated by the production of colour on coupling with diazotized p-nitroaniline. Drug concentrations in blood from chicks and humans rose rapidly after oral administration. In tissues from chicks, particularly liver and lung, the drug persisted for a long period. An unsuccessful attempt was made to induce resistance to 377C54 in a strain of P. gallinaceum. Extensive pharmacological investigation showed that 377C54 possessed no special pharmacological properties. 相似文献
60.