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1.
Analysis of deaths in patients awaiting heart transplantation: impact on patient selection criteria. 总被引:1,自引:0,他引:1
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G. A. Haywood P. R. Rickenbacher P. T. Trindade L. Gullestad J. P. Jiang J. S. Schroeder R. Vagelos P. Oyer M. B. Fowler 《Heart (British Cardiac Society)》1996,75(5):455-462
OBJECTIVE: To analyse the clinical characteristics of patients who died on the Stanford heart transplant waiting list and to develop a method for risk stratifying status 2 patients (outpatients). METHODS: Data were reviewed from all patients over 18 years, excluding retransplants, who were accepted for heart transplantation over an eight year period from 1986 to 1994. RESULTS: 548 patients were accepted for heart transplantation; 53 died on the waiting list, and 52 survived on the waiting list for over one year. On multivariate analysis only peak oxygen consumption (peak VO2: 11.7 (SD 2.7) v 15.1 (5.2) ml/kg/min, P = 0.02) and cardiac output (3.97 (1.03) v 4.79 (1.06) litres/min, P = 0.04) were found to be independent prognostic risk factors. Peak VO2 and cardiac index (CI) were then analysed in the last 141 consecutive patients accepted for cardiac transplantation. All deaths and 88% of the deteriorations to status 1 on the waiting list occurred in patients with either a CI < 2.0 or a VO2 < 12. In those with a CI < 2.0 and a VO2 < 12, 38% died or deteriorated to status 1 in the first year on the waiting list. Patients with CI > or = 2.0 and a VO2 > or = 12 all survived throughout follow up. Using a Cox's proportional hazards model with CI and peak VO2 as covariates, tables were constructed predicting the chance of surviving for (a) 60 days and (b) 1 year on the waiting list. CONCLUSIONS: These data provide a basis for risk stratification of status 2 patients on the heart transplant waiting list. 相似文献
2.
3.
Cellular mechanisms of toxicity and tolerance in the copper-loaded rat. I. Ultrastructural changes in the liver 总被引:3,自引:0,他引:3
Ultrastructural changes have been studied in the copper-loaded livers of rats in order to clarify the pathogenesis of damage induced by the metal and the subsequent recovery. Male rats fed a high copper diet (1500 ppm) for 16 weeks were killed at intervals. Their livers were removed and portions fixed in 4% paraformaldehyde and 2% glutaraldehyde for transmission electron microscopy and analysed for copper by AA spectrophotometry. Increasing copper concentrations were associated with an increase in the numbers and diversity of lysosomes, swelling of smooth endoplasmic reticulum, mitochondria and canalicular microvilli and fragmentation of rough endoplasmic reticulum. Nuclear degeneration occurred early, culminating in lysis. Subsequent changes included a decline in liver copper, extrusion of apoptotic bodies and the recovery of remaining hepatocytes with retention of inert remnants (Mallory body-like structures). Excess copper is associated primarily with irreversible nuclear damage and does not appear to cause disruption of lysosomes. The mechanism of cellular adaptation remains unclear. 相似文献
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5.
L. J. Haywood C. Faucett M. deGuzman K. Ell S. Norris E. Butts 《Journal of the National Medical Association》1998,90(4):241-252
The Rose Questionnaire, developed to facilitate screening for the presence of coronary artery disease, has shown good utility for white men and more variable utility among Latino, African-American, and female subjects. This study investigated its utility for prediction of outcome in patients with suspected myocardial infarction. A total of 1428 white, Latino, and African-American subjects completed questionnaires after emergency admission, which were correlated with diagnoses at the time of discharge from a public hospital and private hospital. Results indicated that subjects with positive questionnaires were less likely to have infarction confirmed at discharge, except for those with a prior history of myocardial infarction, than those with a negative response. These data are important in evaluating the overall utility of the Rose Questionnaire and the significance of angina. 相似文献
6.
New reference allelic ladders to improve allelic designation in a multiplex STR system 总被引:4,自引:0,他引:4
R. A. L. Griffiths M. D. Barber P. E. Johnson S. M. Gillbard M. D. Haywood C. D. Smith J. Arnold T. Burke A. J. Urquhart P. Gill 《International journal of legal medicine》1998,111(5):267-272
This paper reports the composition of a new reference allelic ladder mixture for use with a multiplex DNA profiling system
consisting of six short tandem repeat loci. The loci included in this mixture are HUMTH01, D21S11, D18S51, D8S1179, HUMVWAF31/A,
HUMFIBRA/FGA and an amelogenin sex test. Sequence analysis of individual ladder alleles was carried out and allelic designations
made in accordance with the recommendations of the International Society of Forensic Haemogenetics (1992; 1994). A series
of rare alleles which increase the range of alleles previously reported were identified. By including some of the rare alleles
into the ladder marker system, we have significantly improved the ability to identify new alleles in unknown samples.
Received: 12 August 1997 / Received in revised form: 7 November 1997 相似文献
7.
Salim H. Khalil Mohammed H. Qari John M. Jackson Robert Haywood Pyle Hassan El-Solh Abdallah Al-Nasser 《Leukemia research》1994,18(12):881-883
Geographical variations in the incidence of disease are of considerable theoretical and practical importance. It has been claimed that the distribution of acute lymphoblastic leukemia (ALL) phenotypes in Saudi Arabia is different from that recorded in the Western literature. One hundred and twelve (112) patients under 15 years of age, diagnosed as ALL between January 1992 and May 1994 had immunophenotypes performed on their blast cells. Common ALL (cALL) together with pre-B-ALL, formed 86.5% of the total; B-cell 3%, T-cell 6% and null cell 4.5%. These figures are not significantly different from the Western literature. A previous claim from this institution in 1990, that both null and B-cell ALL were significantly increased compared with elsewhere, is not supported by the present figures. Age and sex distribution, and FAB classification, L1 77%, L2 20% and L3 3%, were also of the same order as described elsewhere and, in particular, there was no increase in the frequency of L3 subtype. 相似文献
8.
Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献
9.
Long-term prognosis was studied in 72 patients with an ejection fraction (EF) of less than 50 percent after medically treated myocardial infarction. The patients ranged in age from 22 to 67 years. Eighteen deaths (25 percent mortality) occurred during the mean follow-up period of three years. The mortality for patients with EF ≥ 30 percent was 43 percent compared with 14 percent for EF ≥ 40 percent and 18 percent for EF ≥ 50 percent. Nonsurvivors had significantly higher left ventricular end diastolic (LVED) pressure (23.4 ± 7 mmHg vs 17.5 ± 8 mmHg, P < .006), higher LVED volume (264 ± 76 vs 225 ± 76, P < .05), and lower EF (27.12 vs 36 ± 10, P < .01). A higher percentage of nonsurvivors had complications during acute myocardial infarction (83 ± 8 percent vs 48.5 percent, P < .001). Overall survival rates were better than previously reported for patients with poor left ventricular function (LVF); complications during myocardial infarction and severity of LVF as measured by EF, LVED pressure, and LVED volume were powerful prognostic indicators. 相似文献
10.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献