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611.
AS NARULA HS BALI V SAKHUJA KS CHUGH HS OBEROI 《Medical Journal Armed Forces India》1996,52(2):110-112
Thirty eight patients underwent Holter ECG monitoring for a 48 hour period covering dialysis and intermediate period to detect incidence of myocardial ischemia manifesting as ST segment changes. Seventeen patients (44.7%) had 165 episodes of dynamic ST segment changes lasting from 1 to 177 minutes, with maximum ST depression of 4 mm. The mean age of patients was 45 ± 14 years and 14 (82.6%) of them were males. Ten (58.8%) patients had hypertension, and 5 (29.4%) patients each had diabetes mellitus and pre-existing coronary artery disease. Six (35.3%) patients with dynamic ST segment changes had ventricular ectopics ranging from isolated ventricular premature contractions to episodes of ventricular tachycardia. No significant hypotension or angina was documented during these episodes of ST segment deviation. We concluded that hemodialysis plays an important role in the genesis of the above ECG changes.KEY WORDS: Ischemic heart disease, Holter monitoring, Renal dialysis 相似文献
612.
Molecular and clinical correlations in autosomal dominant cerebellar ataxia with progressive macular dystrophy (SCA7) 总被引:11,自引:4,他引:11
David G; Durr A; Stevanin G; Cancel G; Abbas N; Benomar A; Belal S; Lebre AS; Abada-Bendib M; Grid D; Holmberg M; Yahyaoui M; Hentati F; Chkili T; Agid Y; Brice A 《Human molecular genetics》1998,7(2):165-170
Spinocerebellar ataxia 7 (SCA7) is caused by the expansion of an unstable
CAG repeat in the first exon of the SCA7 gene. We have analyzed the SCA7
mutation in 19 families and one isolated case of various geographical
origins, presenting with autosomal dominant cerebellar ataxia with
progressive macular dystrophy. The SCA7 CAG repeat was expanded in 77
patients and in 11 at-risk individuals, with alleles containing from 37 to
130 repeats, demonstrating that SCA7 is genetically homogeneous. Repeats on
normal alleles contained from 7 to 35 CAGs. There was a strong negative
correlation (r = -0.84) between the age at onset and the size of the CAG
repeat expansion in SCA7 patients. Larger expansions were associated with
earlier onset, a more severe and rapid clinical course, and a higher
frequency of decreased vision, ophthalmoplegia, extensor plantar response
and scoliosis. The frequency of other clinical signs such as dysphagia and
sphincter disturbances increased with disease duration. The mutation was
highly unstable during transmission, with a mean increase of 10 +/- 16 CAG
repeats, which was significantly greater in paternal (15 +/- 20) than in
maternal (5 +/- 5) transmissions. This correlated well with the marked
anticipation (19 +/- 13 years) observed in the families. Gonadal mosaicism,
observed in the sperm of a patient, was particularly important, with
expanded alleles ranging from 42 to >155 CAG repeats. The degree of
instability during transmission, resulting mostly in expansions, is greater
than in the seven other neurodegenerative disorders caused by polyglutamine
expansions.
相似文献
613.
Repeat Expansion Detection (RED) is an efficient and simple method for
detecting repeat expansions in the human genome, including expansion
mutations resulting in disease. Here we report the first population survey
of CTG/CAG repeat lengths in humans using the RED method; we have
determined maximum CTG/CAG repeat length in 244 individuals from six human
populations: Danes, Chinese, Japanese, Rondonian Surui, Maya and
Mbuti/Biaka Pygmies. We have also sampled a number of non-human primates
including eight orang-utans (Pongo pygmaeus), seven gorillas (Gorilla
gorilla), seven pygmy chimpanzees (Pan paniscus), 13 common chimpanzees
(Pan troglodytes) and three Hylobatidae (one Hylobates lar, one H.klossii,
and one H.syndactylus). Our results demonstrate the existence of
significant variation in the sizes and frequencies of the longest CTG/CAG
repeat length seen per individual both within and between human
populations. The population differences argue that overall mutation rates
at CTG/CAG repeat loci are sufficiently low that mutation does not
obliterate the effect of random genetic drift and clearly indicate that
population stratification could occur in disease association studies using
the RED method. No significant differences were detected among the
non-human primates sampled. Our results also show that both common
chimpanzees and pygmy chimpanzees (bonobos) are polymorphic for maximum
length of any CTG/CAG repeats while no variation was found for gorillas and
orang-utans.
相似文献
614.
JB Ziegler CH Lee MB Van der Weyden AS Bagnara J Beveridge 《Archives of disease in childhood》1980,55(6):452-457
A first-born baby boy presented at age 3 months with persistent diarrhoea, failure to thrive, and recurrent bacterial and fungal infections. Severe combined immunodeficiency was demonstrated. A deficiency of adenosine deaminase (ADA) activity was suggested by the presence of extensive skeletal abnormalities, and the ADA activity in erythrocyte and leucocyte lysates was < 0.005 nmol/h per mg protein. Culture of ADA-negative peripheral blood mononuclear cells, together with purified calf ADA, did not alter the absent phytohaemagglutinin response. Treatment with immunoglobulin, pentamidine, and co-trimoxazole was started and a programme of ADA enzyme replacement, with infusions of plasma and frozen irradiated erythrocytes, was begun at age 4 months and achieved blood ADA levels in excess of 30 nmol/h per mg haemoglobin. Although resolution of the interstitial pneumonitis and skeletal abnormalities was observed, there was no evidence of immunological reconstitution. The patient died at age 17 months after a parainfluenza pneumonitis. Features of importance in predicting lack of benefit from enzyme replacement by erythrocyte infusion in ADA-negative severe combined immunodeficiency appear to be early clinical presentation with associated severe skeletal abnormalities, a very low level of residual ADA activity in peripheral blood mononuclear cells, and lack of effect of exogenous ADA on the absent in vitro mitogen response of ADA-negative blood mononuclear cells. 相似文献
615.
616.
Tischler AS; Powers JF; Pignatello M; Tsokas P; Downing JC; McClain RM 《Toxicological sciences》1999,51(1):9-18
Adrenal medullary hyperplasia and pheochromocytomas are induced in rats by
a variety of non-genotoxic agents, and we have hypothesized that these
agents induce lesions indirectly by stimulating chromaffin cell
proliferation. Vitamin D3, which has not been previously associated with
adrenal medullary proliferative lesions, is the most potent in vivo
stimulus to chromaffin cell proliferation yet identified. The present
investigation utilized the vitamin D3 model to prospectively test the
relationship between mitogenicity and focal proliferative lesions in the
adrenal medulla and to determine early events in the pathogenesis of these
lesions. Charles River Crl:CD BR rats were treated with 0; 5000; 10,000; or
20,000 IU/kg/day of vitamin D3 in corn oil (5 ml/kg) by oral intubation.
Rats were killed after 4, 8, 12, or 26 weeks of treatment, following a
final week of labeling with bromodeoxyuridine (BrdU) using a mini-pump.
Adrenal sections were double-stained for BrdU and
phenylethanolamine-N-methyl transferase (PNMT) to discriminate epinephrine
(E) from norepinephrine (NE) cells or for vesicular acetylcholine
transporter (VAchT) to identify cholinergic nerve endings. Vitamin D3
caused a 4-5-fold increase in BrdU labeling at week 4, diminishing to a
2-fold increase by week 26. An initial preponderance of labeled E cells
gave way to a preponderance of labeled NE cells. By week 26, 17/19 (89%)
animals receiving the 2 highest doses of vitamin D3 had focal adrenal
medullary proliferative lesions, in contrast to an absence of lesions in
control rats. The lesions encompassed a spectrum including BrdU-labeled
"hot spots" not readily visible on H and E sections, hyperplastic nodules,
and pheochromocytomas. Lesions were usually multicentric, bilateral, and
peripheral in location, and almost all were PNMT-negative. The lesions were
not cholinergically innervated, suggesting autonomous proliferation. Hot
spots, hyperplastic nodules, and pheochromocytomas appear to represent a
continuum rather than separate entities. Their development might involve
selective responses of chromaffin cell subsets to mitogenic signals,
influenced by both innervation and corticomedullary interactions. A number
of non-genotoxic compounds that induce pheochromocytomas in rats are known
to affect calcium homeostasis. The results of this study provide further
evidence to support the hypothesis that altered calcium homeostasis is
indirectly involved in the pathogenesis of pheochromocytomas, via effects
on chromaffin cell proliferation.
相似文献
617.
AS Pelkonen A Kotaniemi‐Syrjänen K Malmström LP Malmberg MJ Mäkelä 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(8):1175-1179
Aim: To evaluate whether there are any associations between parentally reported symptoms, clinical findings and lung function in young children with recurrent lower respiratory tract symptoms. Methods: In 2000–2003, 148 children, aged 3–26 months, with recurrent lower respiratory tract symptoms underwent physical examination, investigation of a chest radiograph, whole body plethysmography and skin prick testing to common food and inhalant allergens. Results: Lung function was considered abnormal (i.e. functional residual capacity z‐score of ≥1.65 and/or specific conductance z‐score of ≤?1.65) in 83 (56%) children. Findings of increased work of breathing (p < 0.001) and nonspecific noisy breathing sounds (p < 0.001) in the physical examination, as well as an abnormal chest radiograph (p = 0.028) were independently associated with abnormal lung function, explaining up to 34% of the variation in lung function. In contrast, parentally reported respiratory symptoms, environmental exposures or atopic trait were not associated with lung function abnormalities. Conclusion: The results of this study emphasize the importance of the meticulous clinical examination in the evaluation of early childhood respiratory disorders. As physical examination alone cannot predict lung function abnormalities reliably in preschool children with troublesome respiratory symptoms, lung function testing may be considered in such patients to obtain additional objective information. 相似文献
618.
619.
620.