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排序方式: 共有748条查询结果,搜索用时 15 毫秒
1.
目的 探讨血管新生指标CD34、CD31、vWF、Ⅳ型胶原纤维及层粘连蛋白在肝细胞肝癌(HCC)中的表达及意义 ,同时比较上述几种血管新生因子与增殖细胞核抗原 (PCNA)、病理指标及预后的相关性 ,以便筛选出有效的临床预后指标。方法 采用免疫组化方法 ,对 5 3例肝细胞肝癌的标本进行CD31、CD34、vWF、Ⅳ型胶原纤维及层粘连蛋白的染色、计数 ,并用检测数据与患者的临床资料进行统计分析。结果 统计染色的血管面积后发现 ,CD34与多种临床病理指标无相关性 ;CD31与肝内门静脉浸润相关 ;vWF与肿瘤的TNM分期及肝内门静脉浸润呈正相关 ;CollⅣ与肝内门静脉浸润呈正相关、与术后生存期呈负相关 ;Lam与肝硬化及术中出血量呈负相关、与术后生存期呈正相关。PCNA与肿瘤TNM分期有关。结论 在HCC中 ,CollⅣ、vWF、及CD31为肝细胞肝癌的有效血管新生及预后指标 ;Lam则与肝硬化及术中出血相关 ;PCNA指数肿瘤分期有关 ;CD34不能用作血管新生或预后指标 相似文献
2.
A. TSATSOULIS E. WHITEHEAD J. ST. JOHN S. M. SHALET W. R. ROBERTSON 《Clinical endocrinology》1987,27(6):683-689
Eighteen men (mean age 27, range 18-30 years) treated for Hodgkin's disease with 6-8 courses of MVPP (Mustine, Vinblastine, Procarbazine and Prednisolone) have had Leydig cell function assessed by their steroidogenic responses to stimulation by a single bolus dose of HCG (1000 units intramuscularly). Normal age-matched men (n = 16) acted as controls. Baseline immunoreactive FSH was markedly raised in the patients (mean 18.1 +/- SD 6.9 vs 2.0 +/- 1.5 IU/l, P less than 0.0001) reflecting damage to the germinal epithelium. Immunoreactive LH was also greater in patients (10.3 +/- 3.9 IU/l) than in controls (3.9 +/- 1.9 IU/l, P less than 0.0001). There were no differences between the baseline testosterone, androstenedione, oestradiol, oestrone and sex hormone binding globulin (SHBG) concentrations. The testosterone/SHBG ratios were similar in the two groups and there was no correlation between baseline LH and testosterone concentrations or testosterone/SHBG ratios. Testosterone, androstenedione, oestradiol and oestrone secretion in response to HCG stimulation were similar at 24 h and 96 h in both groups. In order to explain the paradox of elevated immunoreactive LH in the face of normal testicular steroidogenesis in such patients, LH biological activity (B) as well as LH immunoreactivity (I) and FSH and testosterone were estimated in a second similar group of patients (n = 17, mean age 27, range 17-43 years) and in a further age-matched control group (n = 17). Bioactive and immunoreactive LH levels were significantly increased (P less than 0.005 and P less than 0.001, respectively) in the patient group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Membrane flow within the myelin sheath in IDPN neuropathy 总被引:1,自引:0,他引:1
A. E. BLAUROCK M. B. GENTER ST CLAIR D. G. GRAHAM 《Neuropathology and applied neurobiology》1991,17(4):309-321
This report describes some aspects of beta,beta'-iminodipropionitrile (IDPN) neuropathy in rats as observed by ultrastructural methods and X-ray diffraction. Light microscopy shows gross swelling of the axons in proximal lumbar spinal roots 8 days after intraperitoneal injection of IDPN. Mean axon cross-sectional area and mean axon perimeter increased to 280% and 160% of their control values, respectively. At the same time, myelin membrane packing was not visibly disturbed. In addition, X-ray diffraction patterns, recorded under physiological conditions, demonstrate that the myelin lipid bilayer thickness and widths of the aqueous spaces between bilayers did not change. Related observations are made on posterior tibial nerve (PNS myelin) and ventral spinal cord (CNS myelin). The various observations together are interpreted in terms of a fluid myelin membrane. It is proposed that the myelin membrane flows during axon swelling even though normal membrane-membrane contacts are maintained within the sheath. Membrane flow and slippage between membranes are explained in terms of a molecular model of the myelin multilayer. 相似文献
4.
N. J. ST. G. SAUNDERS Lecturer C. BARCLAY Registrar 《BJOG : an international journal of obstetrics and gynaecology》1988,95(10):1060-1062
Summary. In a randomized controlled study of wound suction drainage after transverse suprapubic incision for lower-segment caesarean section no significant advantages could be demonstrated for routine drainage in terms of wound infection, haematoma formation, duration of hospital stay or analgesic requirements. 相似文献
5.
C W Pinson M R Daya K G Benner R L Norton K E Deveney N L Ascher J P Roberts J R Lake A G Kurkchubasche J W Ragsdale 《American journal of surgery》1990,159(5):493-499
Amanita phalloides mushroom poisoning is an increasingly common and potentially lethal problem for which liver transplantation offers definitive therapy in selected patients. When significant liver dysfunction appears, early transfer to a liver transplant center is important to identify appropriate candidates and to begin the search for a donor organ. The clinical course of five severely poisoned patients, four of whom underwent liver transplantation, is reviewed. Indications for transplantation included primarily a markedly prolonged prothrombin time that was only partially correctable and a constellation of findings including metabolic acidosis, hypoglycemia, hypofibrinogenemia, and increased serum ammonia, following a marked elevation in serum aminotransferase levels. Unlike viral fulminant hepatic failure, grade III or IV hepatic encephalopathy, marked elevation of the serum bilirubin level, and azotemia were not indications for transplantation. Resected livers demonstrated hepatocyte viability of 0% to 30%. Manifestations of Amanita poisoning complicating preoperative and/or postoperative care included severe diarrhea, gastrointestinal hemorrhage, hypophosphatemia, bowel edema, and marrow suppression with lymphopenia, thrombocytopenia, and neutropenia. All five patients are well 1 year later. This largest experience with liver transplantation for Amanita poisoning further defines the early clinical and laboratory indications for, and the unique complicating features of, transplantation in this setting. 相似文献
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8.
Krushkal J; Xiong M; Ferrell R; Sing CF; Turner ST; Boerwinkle E 《Human molecular genetics》1998,7(9):1379-1383
Elevated blood pressure is an important risk factor for renal-, cerebro-
and cardiovascular diseases. We used an efficient discordant sib-pair
ascertainment scheme to investigate the impact of the distal end of the
long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing
genes for the alpha1B and beta2 adrenergic receptors and the dopamine
receptor type 1A on variation of systolic blood pressure in young
Caucasians. We measured eight highly polymorphic markers spanning this
positional candidate gene-rich region in 427 individuals from 55
three-generation pedigrees containing 69 discordant sibling pairs, and
calculated multipoint identity by descent (MIBD) probabilities. The results
of genetic linkage and association tests indicate that the region between
markers D5S2093 and D5S462 is significantly linked to one or more
polymorphic genes influencing interindividual variation in systolic blood
pressure levels. Since the alpha1B adrenergic receptor and dopamine
receptor type 1A genes are located close to these markers, these data
suggest that genetic variation in one or both of these G protein-coupled
receptors, which participate in the control of vascular tone, plays an
important role in influencing interindividual variation in systolic blood
pressure levels.
相似文献
9.
Synthesis and function of Actinomyces naeslundii T14V type 1 fimbriae require the expression of additional fimbria-associated genes. 总被引:3,自引:0,他引:3
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The nucleotide sequence of the chromosomal DNA flanking the Actinomyces naeslundii (formerly A. viscosus) T14V type 1 fimbrial structural subunit gene (fimP) was determined. Six open reading frames (ORFs), in the order 5' ORF3, ORF2, ORF1,fimP, ORF4, ORF5, ORF6 3', were identified. ORF1 encoded a protein of 408 amino acid residues (Mr = 39,270) and had significant sequence homology with the A. naeslundii T14V type 1 and A. naeslundii WVU45 type 2 fimbrial structural subunits. An in-frame fusion of ORF1 to the malE gene of the expression vector, pMAL-c2, yielded a protein that was immunostained with antibodies raised against the maltose binding protein and A. naeslundii T14V whole bacteria. Digestion of the fusion protein with factor Xa released a protein (apparent molecular mass of 34 kDa) that was immunostained only with the antibody directed against A. naeslundii T14V whole bacterial cells. Integration plasmids carrying a kanamycin resistance gene (kan) that was used to substitute for ORF1 or for DNA fragments internal to the coding region of the other five ORFs were used to transform A. naeslundii T14V. Neither type 1 fimbriae nor the 65-kDa fimbrial structural subunit was detected in mutants obtained by allelic replacement of ORF1 or ORF2. Mutants obtained by allelic replacement of ORF3 or ORF4 expressed only the 65-kDa fimbrial structural subunit. These mutants did not bind, in vitro, to proline-rich proteins that serve as the receptors for Actinomyces type 1 fimbriae. In contrast, a mutant in which the integration plasmid DNA had been inserted at a site close to the carboxyl terminus of ORF6 expressed type 1 fimbriae and had adherence properties similar to those observed in the wild-type strain. These results demonstrate the existence of additional genes near fimP that are likely to be involved in the synthesis and function of cell surface fimbriae of A. naeslundii T14V. 相似文献
10.
We have investigated further two patterns of neutral protease secretion previously described in cultured human monocytes. Freshly isolated or cultured monocytes were plated onto 125I-fibrin either with or without adherent immune complexes. Fibrinolysis was quantified in the presence or absence of added plasminogen. Freshly isolated monocytes cultured on plain fibrin produced fibrinolysis primarily through secretion of plasminogen activator (PA), while contact with adherent complexes induced the release of plasminogen-independent fibrinolytic enzymes. In vitro differentiation of monocytes led to altered enzyme release. PA secretion rose six-fold over the first 3 days of culture, then decreased. Plasminogen-independent enzyme release fell 70% after 24 hr of culture then declined no further. Whereas adherent complexes inhibited secretion of PA in freshly isolated cells, such complexes stimulated PA activity after 3 or more days of culture. PA secretion from freshly isolated monocytes was inhibited by cycloheximide, indicating a requirement for protein synthesis, and by cytochalasin B. PA secretion was also reduced by the local anaesthetics ethanol, octanol, or lidocaine, but was enhanced by propranolol. The reduced PA activity of freshly isolated monocytes cultured on adherent immune complexes was partially reversed by ethanol or propranolol, but not by cytochalasin B. The plasminogen-independent fibrinolytic activity or monocytes on adherent complexes was enhanced by cytochalasin B, but unaffected by cychloheximide suggesting that the enzymes were granule-associated. This secretion was reduced by preincubation with 8-Br-cAMP and methyl isobutyl xanthine and by the local anaesthetics examined. 相似文献