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641.
This paper describes the surgical method and instruments for placing and anchoring the Apex polyester fibre anterior cruciate ligament (ACL) reconstruction. It then reviews the early clinical findings and describes recent developments. At the time of review, 172 Apex replacements had been implanted in the UK in arthroscopically proven chronic ACL-deficient knees. These had been inserted at eight centres since 1987, and follow up was by a single observer assessing patients by questionnaire, clinical examination, stress X-ray and KT 1000 arthrometer. Patients less than 12 months from surgery were excluded, leaving 95 with a mean follow up of 27 months (range 13 to 66 months) on whom results are based. Assessment showed improved stability after operation and the Apex implant appears to provide a reliable method of stabilizing the ACL deficient knee within the confines of this short-term review. The authors feel that further trials are justified. 相似文献
642.
We have shown recently that adenosine deaminase (ADA)-deficient mice die
perinatally with severe liver cell degeneration. In addition to enzyme
substitution, we report the restoration of viability through introduction
of the human ADA gene. The ADA gene is subject to complex developmental and
tissue-specific regulation. To include the cis- regulatory elements
necessary for correct regulation of the human ADA gene, a large transgenic
locus constituting the human ADA gene with 10 kb of 5' and 4 kb of 3'
flanking sequences was generated by co- injection of two overlapping DNA
fragments into murine zygotes. Probably as a result of extrachromosomal
(homologous) recombination between the fragments, one of the two transgenic
lines contained a reconstituted, functional human ADA gene. As in man,
human ADA expression generally was low in these transgenic mice, but high
in the thymus, spleen and gastro-duodenal part of the gut. Apparently, all
cis- regulatory elements essential for a human expression pattern were
incorporated in the transgene and were functional in the murine background.
Similarly to man, the upper alimentary tract of the transgenic mice
revealed low human ADA activity in contrast to extremely high levels of
murine ADA. The human gene probably lacks the cis-regulatory elements that
target high level murine ADA expression to the murine upper alimentary
tract. ADA-deficient mice rescued by introduction of the human ADA
transgene appeared histologically and immunologically normal. Apparently,
human ADA can complement murine ADA in all tissues, even in the epithelium
of the upper alimentary tract where human ADA activity is as much as
70-fold lower than murine ADA activity in wild-type mice. Clearly, the
lethal phenotype of ADA- deficient mice is due to the absence of ADA.
相似文献
643.
Lalitkumar PG; Sengupta J; Karande AA; Ghosh D 《Human reproduction (Oxford, England)》1998,13(12):3478-3486
Placental protein 14 (PP14) is a glycoprotein which is secreted by
secretory phase endometrium and decidua in women. Despite the suggestion
that PP14 is involved in the process of endometrial maturation for
blastocyst implantation, our understanding in this regard is poor. In the
present study, the concentrations and distribution patterns of
immunodetectable PP14 in the endometrium during proliferative and secretory
phases of normal ovulatory menstrual cycles, as well as in implantation
stage endometrium in naturally mated ovulatory cycles with or without early
luteal phase mifepristone treatment, were investigated using the rhesus
monkey as a primate model. Immunopositive PP14 was observed mainly in
epithelial cells of glands and it was detected in one major immunopositive
band at Mr 28 kDa in tissue homogenate and spent medium. The area of
immunopositive precipitation of PP14 in glands was minimal in follicular
phase endometrium, and was higher (P < 0.01) in early, mid- and late
luteal phase endometrium compared with that in pre- and periovulatory
phases of the cycle, but there was no change in its area profile in the
glandular compartment throughout the luteal phase. Immunopositivity for
PP14 in luminal contents of gland displayed an increasing profile from
early to late secretory phases. Thus, the concentrations and the
distribution of immunodetectable PP14 in luteal phase endometrium of the
rhesus monkey showed marked similarity with those of human endometrium
during the natural menstrual cycle. Although there was no marked change in
the band characterstics for the protein in implantation stage endometrium
following early luteal phase mifepristone treatment, it was markedly
decreased (P < 0.01) in tissue homogenate and in vitro spent medium
along with a lesser (P < 0.02) degree of immunoprecipitation in the
glands in implantation stage samples of mifepristone treatment group
compared with that in control group samples. Thus, the contragestional
effect of early luteal phase mifepristone treatment appears to be
associated with a decrease in the concentration of immunodetectable PP14 in
implantation stage endometrial glands and its secretion in the rhesus
monkey. It remains to be seen whether this decline is caused from direct
antiprogesterone action on endometrial glands during progesterone
dominance, or secondarily from associated retarded development of
endometrium.
相似文献
644.
Greater numbers of human spermatozoa associate with endosalpingeal cells derived from the isthmus compared with those from the ampulla 总被引:2,自引:3,他引:2
Baillie HS; Pacey AA; Warren MA; Scudamore IW; Barratt CL 《Human reproduction (Oxford, England)》1997,12(9):1985-1992
A simple co-culture bioassay system was used to investigate whether or not
the anatomical origin affected the ability of epithelial cells from the
human uterine (Fallopian) tube to 'bind' spermatozoa. This study was also
used to identify some of the factors which may be involved in the
regulation of sperm-epithelial interactions in vitro by comparing different
tissue culture models and assessing the effect of oestradiol concentration.
Epithelial explants harvested from different regions of human uterine tubes
were co-incubated with a known concentration of motile donor spermatozoa.
All results were adjusted to reflect a standard sperm concentration of 5 x
10(6)/ml. More spermatozoa associated per field of isthmic compared to
ampullary epithelium [isthmus 9.5 +/- 0.9, ampulla 7.1 +/- 0.7 (mean +/-
SEM); n = 36, P < 0.05, ANOVA] and cells from post-menopausal patients
had an apparently reduced ability to bind spermatozoa [isthmus 5.5 +/- 2.0,
ampulla 4.3 +/- 1.4 (mean +/- SEM); n = 4]. Neither menstrual cycle stage
nor addition of mid-cycle concentrations of 17beta-oestradiol (750 pmol/l)
affected the number of spermatozoa which bound to epithelium from either
tubal region. In addition, the number of spermatozoa which bound per field
of polarized explants was greater (P < 0.05) than that bound to
dissociated primary and passaged epithelial cell monolayers. This report is
the first to provide evidence suggestive of a role for sperm- epithelial
binding in the formation of an isthmic sperm reservoir in the human uterine
tube. Results also indicate that oestrogen is not involved in the
regulation of these interactions, and that cell polarity is an important
factor for such associations in vitro.
相似文献
645.
646.
ABSTRACT. A study was performed on a Danish school population to obtain reference values of the following serum lipids: total lipid, phospholipid, cholesterol, glycerol and triglyceride. 92 % of 630 children participated, but 23 were excluded following clinical examination. Thus values are given for 301 girls and 274 boys aged 8 to 17 years. 相似文献
647.
Abstract. A study was performed on a Danish school population to obtain reference values of the following serum lipids: total lipid, phospholipid, cholesterol, glycerol and triglyceride. 92% of 630 children participated, but 23 were excluded following clinical examination. Thus values are given for 301 girls and 274 boys aged 8 to 17 years. 相似文献
648.
The effect of continuous positive airway pressure (CPAP) on lung mechanics was investigated in 12 babies after operation for severe congenital heart disease. At the time of study all babies were receiving or being weaned from ventilatory support and had abnormally low lung volume or compliance. During CPAP there was a fall in the pulmonary resistance which, with a slight decrease in minute ventilation, resulted in a significant decrease in the work of breathing. It is suggested that lowering the oxygen cost of breathing may contribute to the improvement in arterial oxygenation seen when CPAP is used. 相似文献
649.
Rolf AA Pelleboer Sander TH Bontemps Paul H Verkerk Paula Van Dommelen Rob Rodrigues Pereira Jacobus P Van Wouwe 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(5):807-811
Aims: To estimate the incidence and clinical characteristics in hospital admissions due to dehydration or undernutrition and their laboratory evaluation and treatment outcome in exclusively breastfed infants.
Methods: All hospital admissions during the first 3 months of life assessed by the Dutch Paediatric Surveillance Unit (DPSU) between mid 2003 and mid 2005.
Results: Nationwide 158 cases reported, correspond to an incidence of 58/y/100 000 breastfed infants; it is lower for severe dehydration at risk for hypernatraemia; 20/y/100 000. Sixty-five per cent of cases were <2 weeks old, their median weight loss was 9.3% and median age at admission 5 days; Serum sodium value was measured in only 12% of all cases. Insufficient volume intake and inadequate growth were most frequently reported (61% and 41%). Lethargy, jaundice or clinical dehydration was scored in 11–25%, seizures or shock in 3%. A breast pump at home was used in only 31%. In the hospital breast pumps were available (82%) as lactation consultants (73%). For treatment 65% was offered formula, in 30% by nasogastric drip. Most admissions lasted up to 3 days, all recovered fully and 33% were breastfed exclusively at discharge.
Conclusion: The incidence of severe dehydration in the Netherlands is relatively low. With extended use of breast pumps at home it could be lower. To prevent complications, we recommend applying a reference weight chart, a full clinical examination and more extensive screening of serum sodium and glucose. 相似文献
Methods: All hospital admissions during the first 3 months of life assessed by the Dutch Paediatric Surveillance Unit (DPSU) between mid 2003 and mid 2005.
Results: Nationwide 158 cases reported, correspond to an incidence of 58/y/100 000 breastfed infants; it is lower for severe dehydration at risk for hypernatraemia; 20/y/100 000. Sixty-five per cent of cases were <2 weeks old, their median weight loss was 9.3% and median age at admission 5 days; Serum sodium value was measured in only 12% of all cases. Insufficient volume intake and inadequate growth were most frequently reported (61% and 41%). Lethargy, jaundice or clinical dehydration was scored in 11–25%, seizures or shock in 3%. A breast pump at home was used in only 31%. In the hospital breast pumps were available (82%) as lactation consultants (73%). For treatment 65% was offered formula, in 30% by nasogastric drip. Most admissions lasted up to 3 days, all recovered fully and 33% were breastfed exclusively at discharge.
Conclusion: The incidence of severe dehydration in the Netherlands is relatively low. With extended use of breast pumps at home it could be lower. To prevent complications, we recommend applying a reference weight chart, a full clinical examination and more extensive screening of serum sodium and glucose. 相似文献
650.
AA Vein H Koppen J Haan GM Terwindt & MD Ferrari 《Cephalalgia : an international journal of headache》2009,29(6):683-686
Headache is a common, but rarely voiced, complaint during space flights, usually attributed to space motion sickness (SMS). We used a specifically designed questionnaire based on the criteria of the International Classification of Headache Disorders, 2nd edn (ICHD-II). Of the 16 male and one female astronauts who participated in the survey, 12 (71%) reported having experienced at least one headache episode while in space, whereas they had not suffered from headache when on earth. There were in total 21 space headache episodes, of moderate to severe intensity in 71%. In two astronauts (12%) the headache and associated symptoms would match the ICHD-II criteria for migraine and in three (18%) astronauts for tension-type headache; in 12 (70%) astronauts the headache was non-specific. The vast majority of headache episodes (76%) were not associated with symptoms of SMS. We conclude that space flights may trigger headaches without other SMS symptoms in otherwise 'super-healthy' male subjects. We propose to classify space headache as a separate entity among the secondary headaches attributed to disorders of homeostasis. 相似文献