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排序方式: 共有792条查询结果,搜索用时 15 毫秒
1.
2.
A C Perkins M V Pimm D A Morgan M L Wastie J R Reynolds R W Baldwin 《Nuclear medicine communications》1986,7(10):729-739
Preliminary clinical studies have been carried out to determine whether the monoclonal antibody 791T/36 would localize in primary lung cancer to an extent sufficient for external detection by gamma scintigraphy. Radiolabelling of the antibody with 131I permitted visualization of three out of eight (38%) tumours using planar imaging with 99Tcm-labelled blood pool subtraction. Radiolabelling of the same antibody with 111In permitted visualization of tumour uptake in nine out of 13 (69%) tumours, without the need for image subtraction. Single photon emission computed tomography (SPECT) studies of seven patients demonstrated concentration of 111In-labelled antibody at the tumour site in each case, four of which were visualized on the planar images. The present study demonstrates localization of the 791T/36 antibody in primary lung carcinoma and confirms the superiority of 111In over 131I as a radiolabel for antibody imaging, especially when emission tomography is performed. These data indicate that further work will be required to determine whether this antibody will be a suitable carrier for cytotoxic agents in the therapy of lung cancer. 相似文献
3.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
4.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
5.
Catt SL; Sakkas D; Bizzaro D; Bianchi PG; Maxwell WM; Evans G 《Molecular human reproduction》1997,3(9):821-825
Controlling the sex of offspring by the separation of X and Y
chromosome-bearing spermatozoa using flow cytometry has been reported as a
clinical technique aiding prevention of X-linked diseases. Although this
technique has resulted in several hundred normal births in animals and at
least one human birth, there is still concern over its genetic safety due
to the involvement of two potentially mutagenic agents: UV light and the
fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly
those considered abnormal, may be more likely to suffer DNA damage
following exposure to mutagenic agents, compared with other mammalian
species. The stability of normal fresh and decondensed human spermatozoa
were examined after exposure to a range of levels of UV and H33342
staining, using an assay that detects endogenous nicks in the DNA of
spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed
human spermatozoa was examined following UV laser, H33342 staining and flow
cytometry treatments utilizing the same assay. There was an increase in the
presence of endogenous nicks when spermatozoa were decondensed compared
with fresh spermatozoa. There was no increase in the incidence of nicks in
any group of spermatozoa after UV and fluorochrome exposure compared with
controls without exposure.
相似文献
6.
Winberg JO; Hammami-Hauasli N; Nilssen O; Anton-Lamprecht I; Naylor SL; Kerbacher K; Zimmermann M; Krajci P; Gedde-Dahl T Jr; Bruckner-Tuderman L 《Human molecular genetics》1997,6(7):1125-1135
Dystrophic epidermolysis bullosa (EBD) is a clinically heterogeneous skin
disorder, characterized by abnormal anchoring fibrils (AF) and loss of
dermal-epidermal adherence. EBD has been linked to the COL7A1 gene at
chromosome 3p21 which encodes collagen VII, the major component of the AF.
Here we investigated two unrelated EBD families with different clinical
phenotypes and novel combinations of recessive and dominant COL7A1
mutations. Both families shared the same recessive heterozygous 14 bp
deletion at the exon-intron 115 boundary of the COL7A1 gene. The deletion
caused in-frame skipping of exon 115 and the elimination of 29 amino acid
residues from the pro-alpha1(VII) polypeptide chain. As a result,
procollagen VII was not converted to collagen VII and the C-terminal NC-2
propeptide which is normally removed from the procollagen VII prior to
formation of the anchoring fibrils was retained in the skin. All affected
individuals also carried missense mutations in exon 73 of COL7A1 which lead
to different glycine- to-arginine substitutions in the triple-helical
domain of collagen VII. Combination of the deletion mutation with a G2009R
substitution resulted in a mild phenotype. In contrast, combination of the
deletion with a G2043R substitution led to a severe phenotype. The G2043R
substitution was a de novo mutation which alone caused a mild phenotype.
Thus, different combinations of dominant and recessive COL7A1 mutations can
modulate disease activity of EBD and alter the clinical presentation of the
patients.
相似文献
7.
Comparison of biodistribution of 791T/36 monoclonal antibody and its Fab/c fragment in BALB/c mice and nude mice bearing human tumor xenografts 总被引:1,自引:0,他引:1
Fab/c fragments, purified from pepsin digest of mouse IgG2b monoclonal antibody (MoAb) 791T/36, consist of one Fab arm and the intact Fc portion. Pharmacokinetic and biodistribution studies in BALB/c mice of radioiodine-labeled 791T/36 MoAb and its Fab/c fragments showed that, due to the presence of the Fc portion, the Fab/c fragment has the same catabolic rate as whole antibody (T1/2 = 64 h). Due to its lower molecular weight (105,000), the Fab/c fragment extravasated more quickly and to a greater extent than whole MoAb in organs in which the vascular endothelium was fenestrated or continuous. In organs in which the vascular endothelium is sinusoidal, such as in liver and spleen, their diffusion capacities were identical. Therefore, Fab/c fragments reconcile advantages of the intact antibody molecule (slow catabolic rate) and Fab or F(ab)2 fragments (increased extravascular diffusion), features required to improve targeting to solid tumors. Data from biodistribution studies in nude mice bearing subcutaneous 791T tumor (antigen positive) and Colo205 tumor (antigen negative) contralaterally showed important differences in the behavior of whole MoAb and Fab/c fragment: (a) Whole MoAb was cleared more rapidly from the body and from the blood than Fab/c fragment; (b) The MoAb was taken up by the spleen (tissue to blood ratio greater than 1 from 12 h after injection over the 3 days of the experiment) and the liver (0.6), whereas Fab/c fragment tissue to blood ratios were only slightly increased (0.34 and 0.35) compared to control nude mice (0.25 and 0.28) for the spleen and liver, respectively, 3 days after injection. Since both MoAb and Fab/c fragment bear the Fc portion, these data suggest that the reputed "nonspecific uptake" of antibodies due to the Fc portion could be an Fc-mediated specific uptake, e.g., uptake of immune complexes; (c) The tumor to blood ratios were 1.7 and 1.2 for MoAb and Fab/c fragment, respectively, from 24 h throughout the experiment, whereas the percentage of injected dose (% of ID) present/g of 791T tumor was at any time greater for Fab/c fragment (8% maximum of ID) than for MoAb (5% of ID). These results were not expected in view of the low immunoreactivity in vitro of Fab/c fragments compared to whole antibody. It is suggested that the distribution and the catabolic rate of whole antibody and its Fab/c fragment at the tumor level are modulated by their respective valency and immunoreactivity for the target cell. 相似文献
8.
M. V. Pimm S. Demignot S. J. Gribben 《Journal of cancer research and clinical oncology》1993,119(7):408-414
The effect of syngeneic anti-idiotypic (anti-id) antibodies on the biodistribution of three murine monoclonal antibodies (mAb) against human tumour-associated antigens, and also on that of their fragments, has been examined in mice using, as a model system, purified anti-id mAb against three different target mAb. With the IgG2b mAb NCRC-2, pretreatment of mice 24 h previously with its IgG1 anti-id mAb NCRC-60 caused clearance of subsequently administered NCRC-2. With the univalent Fab/c fragment of NCRC-2 there was little effect, even with anti-id to Fab/c pretreatment ratios of 201, although immune complexes were present in the circulation. With Fab of NCRC-2, anti-id mAb prolonged blood survival by reducing renal clearance, immune complexes surviving in the circulation. With the IgG1 mAb NCRC-23, immune complexes formed in vivo with the IgG2b anti-id mAb NCRC-59, but with only little hepatic clearance. With the Fab and F(ab)2 fragments of NCRC-23, blood survival was increased in mice pretreated with anti-id mAb, and with Fab this was clearly due to reduced renal clearance. The third mAb, the IgG3 NCRC-48, formed complexes with its IgG2a anti-id mAb NCRC-62, but these survived in the circulation with no accelerated clearance of the target mAb. These results are different from those previously seen with endogenous anti-id responses. They indicate the diversity of effects that anti-id mAb can have on the biodistribution of their target mAb, and emphasise the difficulty of using such anti-id mAb to modulate the pharmacokinetics of target mAb.Abbreviations mAb
monoclonal antibody
- anti-id
anti-idiotypic
- PBS
phosphate-buffered saline, pH 7.2
- T:B
tumour to blood ratio
- AUC
area under curve of plot of surviving radiolabel against time 相似文献
9.
10.
Wang WS; Hsieh RK; Chiou TJ; Liu JH; Fan FS; Yen CC; Tung SL; Chen PM 《Japanese journal of clinical oncology》1998,28(9):551-554
A 54-year-old man was treated with weekly 24-h infusion of high-dose
5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon
cancer. At first, he tolerated the treatment well and no significant
toxicity was identified. After a total of eight courses of treatment, a
stable disease was observed, but mild shortness of breath was found on
occasion. The patient had no previous history of cardiac disease and the
heart performance assessed by left ventricular ejection fraction before
treatment was normal. Unfortunately, acute pulmonary edema with lethal
cardiogenic shock occurred during the ninth course of treatment, in spite
of intensive medical treatment. The chest X-ray showed extreme
cardiomegaly. Repeated assessment of his heart function by echocardiogram
and ventricular ejection fraction revealed a very poor cardiac performance.
Toxic cardiogenic shock during weekly 24-h infusion of high-dose
5-fluorouracil and leucovorin is extremely rare. To the best of our
knowledge, no case has been reported in the English literature. We report a
case and the relevant literature about the incidence, clinical picture and
possible pathophysiology on 5-fluorouracil-related cardioxicity is
reviewed.
相似文献