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251.
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
252.
253.
A. M. Howe A. H. Lipson M. de Silva R. Ouvrier W. S. Webster 《American journal of medical genetics. Part A》1997,71(4):391-396
We present an infant who was exposed to warfarin throughout pregnancy and has warfarin embryopathy. When the child was examined radiologically at 20 months areas of calcification were visible in the septal and alar cartilages of the small external part of the nose. The location of this ectopic calcification is consistent with that seen in an animal model of the warfarin embryopathy. It supports the hypothesis that warfarin interferes with the prenatal growth of the cartilaginous nasal septum by inhibiting the normal formation of a vitamin K-dependent protein that prevents calcification of cartilage. The child also had severe abnormalities of the cervical vertebrae and secondary damage to the spinal cord. Cervical vertebral anomalies are a relatively common finding in the warfarin embryopathy and in the related Binder syndrome. Am. J. Med. Genet. 71:391–396, 1997. © 1997 Wiley-Liss, Inc. 相似文献
254.
James J. Devlin Amy Liang Lan Trinh Mark A. Polokoff David Senator Wei Zheng Jason Kondracki Peter J. Kretschmer John Morser Samuel E. Lipson Richard Spann John A. Loughlin Kathryn V. Dunn Michael M. Morrissey 《Drug development research》1996,37(2):80-85
A matrix-based compound pooling and deconvolution method has been developed that significantly increased the efficiency of a high-capacity screening program. This method is based on screening pools of 10 compounds. The matrix used to assemble the pools resulted in each compound being assayed twice—each time with a completely different set of pooled compounds. The active compound in an active pool was accurately predicted by determining which compound was present in an active pool both times that a pool containing that compound was tested. This has eliminated the need to re-assay each individual member of active pools. This approach has been tested with a set of 6,680 compounds in three different assays: inhibition of Factor Xa, inhibition of gastrin-releasing peptide receptor binding, and inhibition of nitric oxide synthase (isoform II). Thus significant time is saved not only by pooling the compounds for the initial assay but also by avoiding the need to re-assay all compounds in active pools. Moreover, no false negatives occurred in these assays—an important consideration from a drug discovery perspective. © 1996 Wiley-Liss, Inc. 相似文献
255.
The differential diagnosis of pneumoperitoneum is broad. We report a case of tension pneumoperitoneum in a patient on mechanical ventilation with initially unrecognized pneumothorax who had an indwelling pleural-peritoneal shunt. The patient developed ventilatory and hemodynamic collapse as air was diverted from the pleural space into the peritoneal cavity. Subsequent abdominal exploration revealed the source of the intra-abdominal air. Placement of a chest thoracostomy tube and removal of the pleural-peritoneal catheter resulted in significant clinical improvement. We suggest that it is important to recognize that pleural-peritoneal catheters may cause tension pneumoperitoneum without obvious concurrent pneumothorax. 相似文献
256.
257.
目的:研究Down’s 综合征动物模型trisomy 16 结肠神经系发育和先天性巨结肠(HD) 病变肠管蛋白基因产物9-5(protein gene product9 .5 ,PGP9-5) 的神经表达。方法:Trisomy 16 鼠培育;细胞遗传学分析;Trisomy 16 鼠结肠和HDPGP9-5 免疫组织化学。结果:(1)Trisomy 16 鼠结肠神经系发育异常,肌间神经丛发育迟缓,粘膜下神经丛缺失,结肠末端有5 mm 的无神经节区,但结肠系膜神经发育良好;(2)HD狭窄段肠管PGP9-5 阳性神经纤维大量增生,神经节细胞缺如。结论:(1)Trisomy 16 鼠具有稳定的遗传学特征,可能伴先天性巨结肠。(2) 由于HD 狭窄段肠管神经节细胞缺失,增生的PGP9-5 阳性神经纤维是肠道外源性神经的代偿,对其神经元的性质尚有待确定。(3)HD有遗传倾向 相似文献
258.
J T Albright B L Lebovitz R Lipson J Luft 《International journal of pediatric otorhinolaryngology》1999,49(1):63-67
Volatile substance abuse has become increasingly popular among today's youth. It has reportedly been used by up to 13% of teenage populations. Physicians need to be aware of the potential complications which may arise from this form of substance abuse. We describe the case of a young male who presented with massive edema affecting his lips, oral cavity, oropharynx and trachea. It was later discovered that his injury was secondary to thermal trauma related to the abuse of a fluorinated hydrocarbon propellant. This presentation may easily be confused with allergic or angioneurotic edema. Denial by the patient can lead to a further delay in diagnosis. This case is especially notable since frostbite injury involving the upper aerodigestive tract is extremely rare. We discuss the differential diagnosis and the management principals required in the care of this patient. We also present a pertinent review of the literature related to both volatile substance abuse and its complications involving the airway. 相似文献
259.
Experimental intervertebral disc degeneration produced in rabbits by ventral nuclear herniation reliably produces vertebral osteophytes. Osteophytes arise from proliferating inner annular fibers which undergo metaplasia into cartilage, calcify, and proceed through an endochondral ossification sequence. Proteoglycans extracted from the osteophytes reveal that the degree of aggregation, molecular size of the monomer, and the chondroitin sulfate/keratin sulfate ratio are directly related to the cartilage state of the tissue. 相似文献
260.
The degradation of fibrillar type II collagen is a major feature of
cartilage destruction in rheumatoid arthritis (RA). Since collagenase 3 is
produced by chondrocytes and preferentially degrades type II cartilage
collagen, it seemed likely that this enzyme would have a prominent role in
the destruction of rheumatoid joints. Using immunolocalization techniques,
we have examined and compared the production and distributions of
collagenase 1 and collagenase 3 in cells and tissues derived from
rheumatoid knee arthroplasties. Primary cultures of chondrocytes stimulated
with interleukin-1 beta showed that most of the cells produced collagenase
1, whereas only a minority (approximately 5-10%) produced collagenase 3; a
few chondrocytes demonstrated the co-ordinate production of both enzymes.
Primary cultures of rheumatoid synoviocytes produced collagenase 1, but not
collagenase 3. Both enzymes were demonstrated in the rheumatoid lesion.
Collagenase 1 was more commonly observed in both synovium and cartilage (22
of the 28 specimens), was especially prominent at cartilage erosion sites,
and most of the positive specimens demonstrated extracellular enzyme. By
contrast, collagenase 3 was observed less frequently (7/28 specimens) and
was produced by relatively few chondrocytes and synovial cells, this
usually being much less than that observed for chondrocytes of
osteoarthritic cartilage. These observations suggest different regulatory
mechanisms for the production of collagenases 1 and 3 in the rheumatoid
lesion, and demonstrate that the distribution and production of collagenase
1 are far more prevalent than those for collagenase 3.
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