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排序方式: 共有363条查询结果,搜索用时 15 毫秒
91.
Layman LC; Edwards JL; Osborne WE; Peak DB; Gallup DG; Tho SP; Reindollar RH; Roach DJ; McDonough PG; Lanclos KD 《Molecular human reproduction》1997,3(4):315-320
Women with recurrent abortion, primary unexplained infertility, and
gestational trophoblastic neoplasia (GTN) manifest disordered human
chorionic gonadotrophin (HCG) secretion. Mutations in the HCG
beta/luteinizing hormone (LH) beta gene complex could cause aberrant HCG
production in these disorders. The purpose of this study was to determine
whether HCG beta gene deletions occur in women with recurrent abortion or
primary unexplained infertility, and whether HCG beta gene duplications are
present in women with GTN. DNA was extracted from 10 patients with
unexplained recurrent abortion, 10 patients with unexplained primary
infertility, 12 patients with GTN, three partners of women with GTN, and 30
controls. Southern blots were constructed and hybridized with DNA probes
for HCG beta-5 and the LH beta gene. No gene deletions were identified in
patients with recurrent abortion or primary unexplained infertility.
Likewise, no gene duplications were identified in women with GTN. A
previously described Mbol restriction fragment length polymorphism (RFLP)
was identified in both patients and controls. A new Pstl RFLP was also
characterized, but was present in patients and controls.
Deletion/duplication mutations in the HCG beta/LH beta gene complex do not
appear to be common causes of aberrant HCG production in humans with these
disorders.
相似文献
92.
93.
94.
Dental material artifacts on MR images 总被引:2,自引:0,他引:2
Hinshaw DB Jr; Holshouser BA; Engstrom HI; Tjan AH; Christiansen EL; Catelli WF 《Radiology》1988,166(3):777-779
Magnetic resonance (MR) imaging of the head and neck is becoming an important aid in evaluating pathologic conditions of the brain, midface, and pharynx. Certain dental materials cause artifacts during MR imaging of the lower midface. These artifacts can obscure the normal anatomy. This study describes the degree of artifact production caused by various materials commonly used in dental restorations. Of the materials tested, those causing artifacts were made of stainless steel, such as orthodontic bands used for braces, and pins or posts that are commonly drilled into teeth to provide structure or stability before filling. Materials used as temporary or permanent fillings or crowns--such as amalgam, gold alloy, aluminum, microfilled resin, and polyvinyl acrylics--did not cause artifacts in the images. 相似文献
95.
Gelzleichter TR; Bermudez E; Mangum JB; Wong BA; Janszen DB; Moss OR; Everitt JI 《Toxicological sciences》1999,49(1):93-101
The present study was designed to determine whether pleural fiber burdens
or subchronic pleural fibroproliferative and inflammatory changes can help
explain the marked interspecies differences in pleural fibrosis and
mesothelioma that are observed following long-term inhalation of RCF-1
ceramic fibers by rats and hamsters. Fischer 344 rats and Syrian golden
hamsters were exposed to RCF-1 for 4 h per day, 5 days per week, for 12
consecutive weeks. Lung and pleural fiber burdens were characterized during
and after exposure. For all time points, approximately 67% of fibers
associated with lung tissues from both rats and hamsters were longer than 5
microns in length. In comparison, fibers longer than 5 microns recovered
from the pleural compartment, following a 12-week exposure and 12 weeks of
recovery, accounted for 13% (hamsters) and 4% (rats) of the distribution.
In the 12 weeks after the cessation of exposure, the number of fibers
longer than 5 microns in length remained constant in the hamster at
approximately 150 fibers per cm2 pleura. This was 2 to 3 times the
corresponding fiber surface density in the rat. Significant pulmonary and
pleural inflammation was detected at all time points and for both species.
DNA synthesis by pleural mesothelial cells was quantified by
bromodeoxyuridine uptake following 3 days of labeling. Labeling indices
were higher in hamsters than in rats, both for RCF-1-exposed and filtered
air-control animals and was highest for the parietal surface of the pleura.
Significantly greater collagen deposition was measured in the visceral
pleura of hamsters 12 weeks post-exposure but was not significantly
elevated in rats. These findings demonstrate that subchronic inhalation
exposure to RCF-1 induces pleural inflammation, mesothelial-cell turnover,
pleural fibrosis, and an accumulation of fibers with a length greater than
5 microns in the hamster. The accumulation of long fibers in the pleural
space may contribute to the pathology observed in the hamster following
chronic inhalation of RCF- 1, whereas the presence of short, thin fibers
may play a role in the acute-phase biological response seen in both
species.
相似文献
96.
97.
A novel protein tyrosine phosphatase gene is mutated in progressive myoclonus epilepsy of the Lafora type (EPM2) 总被引:13,自引:5,他引:8
Serratosa JM; Gomez-Garre P; Gallardo ME; Anta B; de Bernabe DB; Lindhout D; Augustijn PB; Tassinari CA; Malafosse RM; Topcu M; Grid D; Dravet C; Berkovic SF; de Cordoba SR 《Human molecular genetics》1999,8(2):345-352
Progressive myoclonus epilepsy of the Lafora type or Lafora disease (EPM2;
McKusick no. 254780) is an autosomal recessive disorder characterized by
epilepsy, myoclonus, progressive neurological deterioration and
glycogen-like intracellular inclusion bodies (Lafora bodies). A gene for
EPM2 previously has been mapped to chromosome 6q23- q25 using linkage
analysis and homozygosity mapping. Here we report the positional cloning of
the 6q EPM2 gene. A microdeletion within the EPM2 critical region, present
inhomozygosis in an affected individual, was found to disrupt a novel gene
encoding a putative protein tyrosine phosphatase (PTPase). The gene,
denoted EPM2, presents alternative splicing in the 5' and 3' end regions.
Mutational analysis revealed that EPM2 patients are homozygous for
loss-of-function mutations in EPM2. These findings suggest that Lafora
disease results from the mutational inactivation of a PTPase activity that
may be important in the control of glycogen metabolism.
相似文献
98.
Impaired growth in children with asthma during treatment with conventional doses of inhaled corticosteroids 总被引:1,自引:0,他引:1
We describe 6 (4F, 2M) prepubertal children with moderate asthma diagnosed at a mean age of 2.8 years. All patients were treated with inhaled corticosteroids in a dose of between 300 and 800 mcg of beclomethasone diproprionate (becotide) daily, given either as an aerosol or rotahaler. Mean height velocity SDS decreased from −0.8(range +0.5 to −2.0)to −3.2(range −1.3 to −4.8) when the dose was increased. Alternatively, when the dose was reduced or stopped, mean height velocity SDS increased from −3.2 (range −2.0 to −4.8) to +0.8 (range −1.2 to +2.7). Careful assessment of height velocity is indicated in all children receiving treatment with inhaled corticosteroids. 相似文献
99.
Two young children with salt-losing congenital adrenal hyperplasia developed profound hypoglycaemia. In one child hypoglycaemia occurred after a prolonged fast and in the other it was precipitated by infection. This complication may be more common than the literature suggests, and emergency treatment with glucose or hydrocortisone, given by injection, should be given to any child with the disorder who suddenly or unexpectedly collapses. 相似文献
100.
Fiorentini G Poddie DB De Giorgi U Guglielminetti D Giovanis P Leoni M Latino W Dazzi C Cariello A Turci D Marangolo M 《Medical oncology (Northwood, London, England)》2000,17(3):163-173
Liver metastases of colorectal cancer is present in more than 20% of new diagnosed patients and in 40–60% of relapsed patients.
It is a life-threatening prognostic aspect. Hepatic resection, when possible, is the best therapeutic modality, although the
overall survival rate is still low (30%). Angiography and intraoperative ultrasonography are useful for resection. The number
of hepatic metastases and the surgical margin are probably the most significant prognostic factors. Colorectal cancer may
spread predominantly to the liver making regional treatment strategies viable options. Subtotal hepatic resections and segmentectomies
are potentially curable procedures for single or small numbers of hepatic metastases without other sites of disease. However,
there have been no prospective randomized trials comparing patients with unresected liver metastases and resected metastases.
Regional chemotherapy with floxuridine seems usefull combined with hepatic resection or as palliative therapy. Gastric ulcer
and biliary sclerosis are the main related toxicities. Patients with localized, unresectable hepatic metastases or concomitant
bad medical condition may be candidates for radiation, percutaneous ethanol injection, cryosurgery, percutaneous radiofrequency,
hypoxic flow-stop perfusions with bioreductive alkylating agents, hepatic arterial ligation, embolization and chemoembolization.
These new hepatic-directed modalities of treatment are being investigated and may offer new approaches to providing palliation
and prolonging survival. This review will report the possibilities of intra-arterial chemotherapy and other novel hepatic-directed
approaches to the treatment of liver metastases from colorectal cancer. 相似文献