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431.
The relation between platelet buoyant density and beta-thromboglobulin (beta-TG), a marker for platelet alpha-granule content, was assessed by three independent approaches. (1) Platelets were separated on iso- osmolar discontinuous Stractan density gradients into five fractions, ranging in density from 1.061 g/ml to 1.091 g/ml (20 degrees C). The beta-TG content (mean +/- SD, n = 17) increased with the platelet density from 27.8 +/- 8.6 micrograms beta-TG/10(9) cells (20% less- dense platelets) up to 65.6 +/- 15.5 micrograms beta-TG/10(9) cells (15% most-dense platelets). (2) Activation of platelets in platelet- rich plasma with thrombin, adenosine diphosphate, collagen, or epinephrine resulted in a decreased density of the platelets. This was only seen when there was simultaneous secretion of beta-TG. (3) The less-dense and the more-dense platelet fractions, after isolation by density gradient centrifugation, were separately treated with thrombin. After complete degranulation, the density distribution of the originally less-dense and more-dense platelets were identical and were much narrower than the density distribution of resting platelets. 相似文献
432.
433.
Features of Aicardi's syndrome include infantile spasms associated with pathognomonic chorioretinopathy, abnormalities of the corpus callosum with heterotopia of gray matter, and characteristic electroencephalographic findings. Vertebral abnormalities are also part of the syndrome, which is apparently limited to female infants. Subnormal mental development appears in all cases. It was first described in 1969 in French. Isolated cases in the literature have been associated with facial asymmetry, plagiocephaly, and the Dandy-Walker syndrome. Experience with two patients suggests that a search for cases among patients with chorioretinopathy and infantile spasms will show the syndrome to be more common than currently reported. 相似文献
434.
NADH-cytochrome b5 reductase is the predominant NADH-diaphorase found in the human neutrophil (Blood 62:152, 1983). Although this reductase segregates with the light membranes of nitrogen-cavitated neutrophils separated on Percoll gradients (which include the plasma membrane markers alkaline phosphatase and NADPH-oxidase), it is approximately 95% excluded from plasma membrane-enriched phagocytic vacuoles. The reductase constitutes approximately 5% of the light membrane fraction FAD-flavoprotein (14.8 +/- 5.5 pmol/mg protein) and was found in equimolar concentration with a high potential b cytochrome also present in this light membrane fraction and tentatively identified as cytochrome b5. Isolation of the reductase from human neutrophils was accomplished by Triton X-114 solubilization of the light Percoll gradient membranes, followed by temperature-dependent phase separation and then affinity chromatography on AMP-Sepharose. The active preparation contained 1.3 mol FAD/mol protein, migrated on sodium dodecyl sulfate-polyacrylamide gels as a single band corresponding to an apparent mol wt of 45,000 daltons, exhibited a pl of 5.7 on chromatofocusing and was obtained in greater than 70% yield, with an overall purification of almost 900-fold. The purified enzyme was characterized by a high specificity for NADH as electron donor (Km = 6.4 mumol/L v Km greater than 1.6 mmol/L for NADPH) and exhibited a maximal turnover of ca. 30,000 min-1 at 22 degrees C with either ferricyanide or cytochrome b5 (Km = 10 nmol/L) as electron acceptor. Although the physical characterization and biochemical properties described here demonstrate that this neutrophil NADH b5 reductase is similar to the corresponding liver and erythrocyte enzymes, its unique function in the neutrophil has yet to be determined. 相似文献
435.
Parietal wound drainage in abdominal surgery 总被引:1,自引:0,他引:1
A prospective randomized study of wound drainage in 250 surgical abdominal wounds was undertaken to determine (a) what effect wound drains had on clean surgical wounds; (b) whether wound drains reduced infection in potentially contaminated wounds; (c) whether wound drainage was an acceptable alternative to the use of topical antibiotics in frankly contaminated wounds. Ten per cent of clean wounds which had been drained became infected, compared with 2 per cent of control wounds in the same group (P less than 0.002). Infection was also more common in potentially and frankly contaminated wounds in the presence of a drain. Skin organisms were grown from 8 drained and 2 nondrained wounds in this group (P less than 0.005), suggesting contamination by the drains. Drains were, however, associated with a lower infection rate in 23 obese patients with frankly contaminated wounds. 相似文献
436.
437.
Differential regulation of leucine-rich primary response gene 1 (LRPR1) mRNA expression in rat testis and ovary 总被引:1,自引:0,他引:1
Slegtenhorst-Eegdeman KE; Verhoef-Post M; Parvinen M; Grootegoed JA; Themmen AP 《Molecular human reproduction》1998,4(7):649-656
In immature rat Sertoli cells, leucine-rich primary response gene 1 (LRPR1)
represents a follicle stimulating hormone (FSH)-responsive gene; the
function of the encoded protein is not yet known. LRPR1 mRNA expression is
up-regulated very rapidly and specifically by FSH, both in cultured Sertoli
cells and in vivo in regulation in more detail, in testis and ovary of
fetal, immature, and adult rats. In addition, we have studied the
expression of FSH receptor (FSHR) mRNA in relation to LRPR1 mRNA
expression. In rat testis, LRPR1 mRNA and FSHR mRNA followed a similar
expression pattern, during postnatal development and also at different
stages of the spermatogenic cycle in the adult rat. Furthermore, after
short-term challenge of the FSH signal transduction pathway in intact
immature rats by injection with a relatively high dose of FSH, an inverse
relationship between LRPR1 mRNA (up-regulation) and FSHR mRNA expression
(down-regulation) was observed. Similar studies in the ovary provided
completely different results. LRPR1 mRNA in the postnatal ovary is present
well before expression of FSHR mRNA can be first detected. In addition,
incubation of ovaries of immature rats with FSH or dibutyryl cyclic AMP
(dbcAMP) did not result in up- regulation of LRPR1 mRNA expression. During
fetal development, the LRPR1 mRNA expression pattern involved many more
tissues, in contrast to the relatively tissue-specific expression of LRPR1
mRNA in gonads of 21 day old and adult rats. Moreover, LRPR1 mRNA
expression could be detected as early as 12.5 days post-coitum, whereas
FSHR mRNA is absent at this stage of fetal development. We concluded that
the pronounced regulation of LRPR1 by FSH observed in the immature rat
testis does not occur in the ovary. Furthermore, in the ovary LRPR1 mRNA
expression does not appear to be dependent on FSH action. Finally, the
LRPR1 gene product may play a general role during fetal development.
相似文献
438.
Thromboembolic disease associated with ovarian stimulation and assisted conception techniques 总被引:5,自引:6,他引:5
Thromboembolic disease, as a complication of ovarian stimulation and
assisted conception techniques, is generally considered to be a rare
complication of ovarian hyperstimulation syndrome and, by implication,
lower limb in origin. Sporadic cases of unusually sited thromboses, both
venous and arterial, have been reported. This paper aims to draw attention
to the relatively large number of such thromboses reported in the world
literature compared with those cited in previous commentaries, and to
emphasize how little is known about their pathogenesis. It is believed that
this is an issue which requires to be addressed in order to understand the
background pathology to such incidents and if possible to identify women at
greatest risk from such potentially debilitating or fatal complications,
such that appropriate prophylactic measures can be taken.
相似文献
439.
Identification of ovarian antibodies by immunofluorescence, enzyme- linked immunosorbent assay or immunoblotting in premature ovarian failure 总被引:3,自引:2,他引:3
Wheatcroft NJ; Salt C; Milford-Ward A; Cooke ID; Weetman AP 《Human reproduction (Oxford, England)》1997,12(12):2617-2622
The development of new techniques for the detection of ovarian antibodies
has challenged early concepts about the rarity of ovarian antibodies in
idiopathic premature ovarian failure (POF), but few attempts have been made
to compare results between assays. We have sought to define the prevalence
of ovarian autoimmunity in a group of 30 idiopathic POF patients compared
to a group of 12 patients with POF plus an associated autoimmune disease
and a group of 38 controls, using an enzyme-linked immunosorbent assay
(ELISA) and indirect immunofluorescence (IFL). Ovarian antibodies were
detected in 27% of idiopathic POF patients by ELISA (not significantly
different compared to POF patients with associated autoimmune disease; P
< 0.0003 compared to controls) but only 7% of these patients were
positive by IFL. In a further, pre-selected group of individuals, all
positive for ovarian antibodies by IFL, 53% had measurable antibodies by
ELISA. Some overlap was therefore demonstrated between the two techniques
but many POF patients had ovarian antibodies detectable by only one method.
Immunoblotting studies revealed that no consistent pattern of binding could
be demonstrated for these patients. These results call into question the
specificity of ovarian antibodies as a marker for autoimmune POF.
相似文献
440.
Jillella AP Britt GW Litaker MS Kallab AM Harkness K Garner GD 《Medical oncology (Northwood, London, England)》2000,17(4):287-292
Our purpose was to determine the risk of ototoxicity in breast cancer patients receiving a myeloablative regimen consisting
of cyclophosphamide 6000 mg/m2, thiotepa 500mg/m2 and carboplatin 800mg/m2 (CTCb) followed by stem cell transplantation.
Fourteen consecutive patients with breast cancer were treated with high dose chemotherapy consisting of the CTCb regimen followed
by stem cell transplantation. A pretransplant complete hearing study was obtained which consisted of hearing case history,
audiometry and tympanometry. In addition, DPOAE (Distortion Product Otoaccoustic Emissions) was done to evaluate measurable
changes in the cochlear (outer hair cell) functioning.
Pre-transplant, all patients had no clinical evidence of hearing impairment and hearing studies were normal. Eleven patients
had hearing studies and a telephone interview posttransplant. One patient was lost to follow-up and two patients died. One
of the 11 patients tested had an abnormal post-transplant hearing study but none of them had clinically detectable hearing
impairment.
In our prospective study of breast cancer patients treated with the CTCb regimen, we did not observe clinically detectable
hearing impairment in any of the patients tested. 相似文献