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991.
Analysis of factors associated with bronchial hyperreactivity to methacholine in bronchiectasis 总被引:1,自引:0,他引:1
Nonspecific bronchial hyperreactivity (BHR) has been reported to occur in patients with bronchiectasis. To evaluate this further,
we studied 77 patients with stable bronchiectasis (noncystic fibrosis) with special reference to the prevalence of BHR to
methacholine (MCh), and its relation to lung function, sputum characteristics, concommitant asthma, and atopy. The concentration
of MCh required to produce a fall of 20% in forced expiratory volume in 1 s (FEV1), PC20, was determined by Wright’s nebulization tidal breathing method. BHR defined by a PC20 ≤ 8 mg/ml was found in 21 of 47 (45%) subjects who underwent bronchial challenge. Presence of BHR was positively associated
with low baseline spirometric values, diagnosis of asthma, long duration of disease, and elevated total IgE on univariant
analysis, and was significantly related to FEV1/forced vital capacity (FVC) ratio and asthma on multiple regression analysis. Ten of the 21 hyperreactive subjects did not
have clinical asthma, whereas all 11 of 22 subjects with clinical asthma who underwent bronchial challenge were hyperreactive.
Among those with BHR, there was a positive correlation between PC20 and baseline FEV1. When patients were further classified into asthmatic and nonasthmatic subjects, a positive correlation between PC20 and FEV1 was seen only in those without asthma. Frequency of infective episodes and inflammatory score of sputum assessed by average
daily volume, purulence, and leukocyte count did not differ significantly in the groups with and without BHR. These results
suggest that BHR in patients with bronchiectasis is associated with coexistent asthma and worse spriometric values, and not
with the severity of bronchial sepsis.
An erratum to this article is available at . 相似文献
992.
For many hospital patients, the experience brings pain and anxiety. Unfamiliar surroundings, various diagnostic and therapeutic procedures, and the sight and sounds of medical procedures exacerbate pain and anxiety. To block off the anxiety-inducing sights and sounds of hospital surroundings and create a pleasing environment, the therapeutic potential of visual stimulation as a nursing intervention was investigated. In a randomized, controlled, cross-over study, pain was produced by a modified tourniquet technique in 46 healthy volunteers. Subjects were randomly allocated to two groups (Group V and Group B) with subsequent cross-over. Those in Group V watched a soundless video display of natural scenery during tourniquet inflation, whereas in Group B subjects watched a static blank screen. Pain threshold was defined as the time when subjects reported the first detectable pain, whereas pain tolerance was the time the pain was reported to be intolerable and deflation of the tourniquet was requested. With the use of visual stimuli, there was a significant increase in pain threshold (P < 0.05) and pain tolerance (P < 0.01). Gender and the sequence of visual stimuli did not have any significant effect on pain threshold and pain tolerance. Further studies specifically addressing level of anxiety and physiological data correlated with pain scores and visual stimuli are needed. The findings have implications for nurses and other healthcare professionals to use various visual stimuli as positive adjuncts to other methods of pain relief and for different pain conditions in clinical areas. 相似文献
993.
Mechanisms of postprandial glucose counterregulation in man. Physiologic roles of glucagon and epinephrine vis-a-vis insulin in the prevention of hypoglycemia late after glucose ingestion. 下载免费PDF全文
The transition from exogenous glucose delivery to endogenous glucose production late after glucose ingestion is not solely attributable to dissipation of insulin and, therefore, must also involve factors that actively raise the plasma glucose concentration--glucose counterregulatory factors. We have shown that the secretion of two of these, glucagon and epinephrine, is specific for glucose ingestion and temporally related to the glucose counterregulatory process. To determine the physiologic roles of glucagon and epinephrine in postprandial glucose counterregulation, we produced pharmacologic interventions that resulted in endogenous glucagon deficiency with and without exogenous glucagon replacement, adrenergic blockade, and adrenergic blockade coupled with glucagon deficiency starting 225 min after the ingestion of 75 g of glucose in normal subjects. Also, we assessed the effect of endogenous epinephrine deficiency alone and in combination with glucagon deficiency late after glucose ingestion in bilaterally adrenalectomized subjects. Glucagon deficiency resulted in nadir plasma glucose concentrations that were approximately 30% lower (P less than 0.01) than control values, but did not cause hypoglycemia late after glucose ingestion. This effect was prevented by glucagon replacement. Neither adrenergic blockade nor epinephrine deficiency alone impaired the glucose counterregulatory process. However, combined glucagon and epinephrine deficiencies resulted in a progressive fall in mean plasma glucose to a hypoglycemic level late after glucose ingestion; the final glucose concentration was 40% lower (P less than 0.02) than the control (epinephrine deficient) value in these patients, and was nearly 50% lower (P less than 0.001) than the control value and approximately 30% lower (P less than 0.05) than the glucagon-deficient value in normal subjects. We conclude (a) the transition from exogenous glucose delivery to endogenous glucose production late after glucose ingestion is the result of the coordinated diminution of insulin secretion and the resumption of glucagon secretion. (b) Epinephrine does not normally play a critical role in this process, but enhanced epinephrine secretion compensates largely and prevents hypoglycemia when glucagon secretion is deficient. 相似文献
994.
van der Put NM; van der Molen EF; Kluijtmans LA; Heil SG; Trijbels JM; Eskes TK; Van Oppenraaij-Emmerzaal D; Banerjee R; Blom HJ 《QJM : monthly journal of the Association of Physicians》1997,90(8):511-517
Elevated homocysteine (Hcy) levels are observed in two apparently unrelated
diseases: neural-tube defects (NTD) and premature vascular disease.
Defective human methionine synthase (MS) could result in elevated Hcy
levels. We sequenced the coding region of MS in 8 hyperhomocysteinaemic
patients (4 NTD patients and 4 patients with pregnancies complicated by
spiral arterial disease, SAD). We identified only one mutation resulting in
an amino acid substitution: an A-->G transition at bp 2756, converting
an aspartic acid (D919) into a glycine (G). We screened genomic DNA for the
presence of this mutation in 56 NTD patients, 69 mothers of children with
NTD, 108 SAD patients and 364 controls. There was no increased prevalence
of the GG and AG genotypes in NTD patients, their mothers or SAD patients.
The D919G mutation does not seem to be a risk factor for NTD or vascular
disease. We then examined the mean Hcy levels for each MS genotype. There
was no correlation between GG- or AG-genotype and Hcy levels. The D919G
mutation is thus a fairly prevalent, and probably benign polymorphism. This
study, though limited, provides no evidence for a major involvement of MS
in the aetiology of homocysteine-related diseases such as NTD or vascular
disease.
相似文献
995.
AC Robinson FRCS J Hanif FRCS LA Dumbreck MA MSC AJ Prichard FRCS BT Manners FRCPath MRCP 《International journal of clinical practice》1997,51(3):138-139
We have estimated that in 1995 more than £2 million was spent by the National Health Service on throat swabs used to investigate chronic tonsillitis in the UK. This study was devised to assess the value of this investigation. The surface microflora, obtained using a throat swab, was compared with the microflora of the deep tonsil in 30 cases of chronic tonsillitis. None of the throat swabs grew pathogenic organisms, while in 16 cases, heavy growths of recognised pathogens were grown from the tonsillar tissue. This paper demonstrates that throat swabs have little value in the management of chronic tonsillitis, and if the investigation was omitted in this condition, a substantial saving could be made. 相似文献
996.
Milani Junior R; Jorge MT; de Campos FP; Martins FP; Bousso A; Cardoso JL; Ribeiro LA; Fan HW; Franca FO; Sano-Martins IS; Cardoso D; Ide Fernandez C; Fernandes JC; Aldred VL; Sandoval MP; Puorto G; Theakston RD; Warrell DA 《QJM : monthly journal of the Association of Physicians》1997,90(5):323-334
The jararacucu, one of the most dreaded snakes of Brazil, southern Bolivia,
Paraguay and northeastern Argentina, is a heavily-built pit viper which may
grow to a length of 2.2 m. Up to 1000 mg (dry weight) of highly-lethal
venom may be milked from its venom glands on a single occasion. It has
accounted for 0.8% to 10% of series of snake bites in Sao Paulo State,
Brazil. We examined 29 cases of proven jararacucu bites recruited over a
20-year period in two Sao Paulo hospitals. Severe signs of local and
systemic envenoming, (local necrosis, shock, spontaneous systemic bleeding,
renal failure) were seen only in patients bitten by snakes longer than 50
cm; bites by shorter specimens were more likely to cause incoagulable
blood. Fourteen patients developed coagulopathy, six local necrosis
(requiring amputation in one) and five local abscesses. Two became shocked
and four developed renal failure. Three patients, aged 3, 11 and 65 years,
died 18.75, 27.75 and 83 h after being bitten, with respiratory and
circulatory failure despite large doses of specific antivenom and
intensive-care- unit management. In two patients, autopsies revealed acute
renal tubular necrosis, cerebral oedema, haemorrhagic rhabdomyolysis at the
site of the bite and disseminated intravascular coagulation. In one
survivor with chronic renal failure, renal biopsy showed bilateral cortical
necrosis; the patient remains dependent on haemodialysis. Effects of
polyspecific Bothrops antivenom were not impressive, and it has been
suggested that anti-Bothrops and anti-Crotalus antivenoms should be given
in combination.
相似文献
997.
Separation of helper and suppressor T lymphocytes on a ficoll velocity sedimentation gradient 总被引:3,自引:2,他引:3 下载免费PDF全文
A 5-20% Ficoll velocity sedimentation gradient has been successfully applied to separate concanavalin A (Con A)-induced helper; and suppressor T cells. When titrated into a constant number of fresh normal spleen cells responding to sheep erythrocytes, cells from the top pool show stimulatory effects while those from the bottom pool show inhibitory activity. Both activities are found to be Con A dependent and anti-theta sensitive. We conclude that Con A-induced helper and suppressor T cells are distinct subpopulations and such separation will allow further characterization of these cell types. 相似文献
998.
999.
A common type of the spectrin alpha I 46-50a-kD peptide abnormality in hereditary elliptocytosis and pyropoikilocytosis is associated with a mutation distant from the proteolytic cleavage site. Evidence for the functional importance of the triple helical model of spectrin. 下载免费PDF全文
P G Gallagher W T Tse T Coetzer M C Lecomte M Garbarz H S Zarkowsky A Baruchel S K Ballas D Dhermy J Palek et al. 《The Journal of clinical investigation》1992,89(3):892-898
We studied nine individuals from five unrelated families with alpha I/46-50a hereditary elliptocytosis (HE) or hereditary pyropoikilocytosis (HPP), including one of the original HHP probands first reported by Zarkowsky and colleagues (1975. Br. J. Haematol. 29:537-543). Biochemical analysis of erythrocyte membrane proteins from these patients revealed, as a common abnormality, the presence of the alpha I/46-50a peptide after limited tryptic digestion of spectrin. The polymerase chain reaction was utilized to study the structure of the DNA encoding the alpha I domain of spectrin in the affected individuals. The DNA sequence of the alpha-spectrin gene encoding the region of the alpha-spectrin chain surrounding the abnormal proteolytic cleavage site was normal. We identified a point mutation causing the replacement of a highly conserved leucine residue by proline at position 207 in the alpha-spectrin chain, a site 51 residues to the amino-terminal side of the abnormal proteolytic cleavage site. Analysis of the proposed triple helical model of spectrin repeats reveals that the mutation occurs in helix 2 at a position directly opposite the abnormal proteolytic cleavage site in helix 3, making this the first report of a mutation occurring in helix 2 of a repeat in the alpha I domain of spectrin. These results add to the molecular heterogeneity of mutations associated with HE/HPP and provide further support for the proposed triple helical model of spectrin. Disruption of this proposed alpha-helical structure by helix-breaking proline substitutions may result in a functionally defective spectrin chain. 相似文献
1000.
Choi Yeung Andy Tse Andus Wong Tara Whitehill Estella Ma Rich Masters 《International journal of speech-language pathology》2016,18(5):465-472
Purpose: In many learning domains, instructions are presented explicitly despite high cognitive demands associated with their processing. This study examined cognitive demands imposed on working memory by different types of instruction to speak with maximum pitch variation: visual analogy, verbal analogy and explicit verbal instruction.Method: Forty participants were asked to memorise a set of 16 visual and verbal stimuli while reading aloud a Cantonese paragraph with maximum pitch variation. Instructions about how to achieve maximum pitch variation were presented via visual analogy, verbal analogy, explicit rules or no instruction. Pitch variation was assessed off-line, using standard deviation of fundamental frequency. Immediately after reading, participants recalled as many stimuli as possible.Result: Analogy instructions resulted in significantly increased pitch variation compared to explicit instructions or no instructions. Explicit instructions resulted in poorest recall of stimuli. Visual analogy instructions resulted in significantly poorer recall of visual stimuli than verbal stimuli.Conclusion: The findings suggest that non-propositional instructions presented via analogy may be less cognitively demanding than instructions that are presented explicitly. Processing analogy instructions that are presented as a visual representation is likely to load primarily visuospatial components of working memory rather than phonological components. The findings are discussed with reference to speech therapy and human cognition. 相似文献