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排序方式: 共有294条查询结果,搜索用时 46 毫秒
81.
82.
Human sperm non-nuclear progesterone receptor expression is a novel marker for fertilization outcome 总被引:1,自引:0,他引:1
Jacob A; Hurley I; Mandel FS; Hershlag A; Cooper GW; Benoff S 《Molecular human reproduction》1998,4(6):533-542
In a prospective, blind study, we have examined the relationship among the
expression of human sperm surface progesterone receptors, the ability to
undergo a mannose-stimulated acrosome reaction and the rate of
fertilization in vitro. Individual aliquots of motile spermatozoa were
surface-labelled with progesterone and/or mannose-fluoresceinated ligands.
Spontaneous acrosome loss and the increase in acrosome reactions following
exposure of spermatozoa to mannose ligands were assessed using rhodaminated
Pisum sativum agglutinin. Progesterone fluoresceinated ligand binding was
observed to occur in two patterns: (i) a uniform distribution of labelling
over the acrosome cap (pattern II), and (ii) labelling limited to the
equatorial and postacrosomal regions of the human sperm head (pattern III).
A conversion of pattern II to pattern III binding was observed and was
associated with the acrosome reaction. Pattern III binding was highly
correlated with both fertilization potential and the ability to undergo a
mannose-stimulated acrosome reaction (P < 0.001). In contrast, normal
sperm mannose receptor expression was seen in five men whose abnormal
progesterone receptor expression/function and inability to acrosome react
after mannose treatment were correlated with their reduced fertility in
vitro. In conclusion, surface progesterone receptor aggregation enhances
the mannose ligand-stimulated acrosome reaction. Such detection of
defective sperm surface progesterone receptor expression/function may be
useful in the evaluation and management of male infertility.
相似文献
83.
84.
Gamete donation in assisted reproduction is an accepted treatment option
for certain infertile couples. Traditionally, men donating spermatozoa have
been paid a nominal fee, whilst women donating oocytes have not. The issue
of payment for sperm donors has recently attracted attention following the
Human Fertilisation and Embryology Authority's (HFEA) suggestion that such
payment may be withdrawn. Prior to the final meeting of the HFEA working
party which is examining this issue, here we report the results of a survey
designed to solicit opinion on whether sperm donors should be paid, to
identify social or other factors which influence this opinion, and to
examine the influence of financial incentive on potential donors. We
surveyed 717 individuals in three distinct groups: the general public,
students (potential donors), and infertility patients (potential
recipients). The majority of the potential donor group (students) was in
favour of paying sperm donors, as were infertility patients. In contrast
the general public was not. The opinion of the general public on this issue
was influenced by their prior knowledge of whether donors were paid: those
of the general public favouring the payment of sperm donors had a prior
awareness that such payments were made. Although not in favour of paying
sperm donors, the general public overwhelmingly approved of the use of
donated spermatozoa for the treatment of infertile couples, and thought
that ways should be sought to increase the availability of donor
spermatozoa for the treatment of infertility and for research purposes.
Within the potential donor group (students), the majority indicated that
financial reward was an important factor which would influence their
decision to donate spermatozoa. As the majority of both the potential
recipients and potential donors feels that sperm donors should be paid,
perhaps the views of these groups should carry significant weight when the
decision whether or not to withdraw payment is taken. This is especially
the case in view of the fact that the majority of the general public is in
favour of the use of donated spermatozoa for the treatment of infertile
couples.
相似文献
85.
BACKGROUND: Allergic reaction is characterized by a complex inflammatory process. Some of the new antihistamines have antiallergic effects and can affect the inflammatory cell recruitment via adhesion molecule downregulation. We aimed to assess in a 12-month study whether continuous treatment with an antihistamine (terfenadine) can reduce respiratory symptoms and local inflammation in children with mite allergy. METHODS: The study was double-blind and placebo-controlled: it involved two parallel groups of children suffering from rhinoconjunctivitis and/or mild intermittent asthma due to mite allergy. They received either terfenadine (1 mg/kg per body weight per day) or placebo for 1 year. Nasal, conjunctival, and bronchial symptoms were recorded by diary cards; at each of the programmed control visits, a nasal scraping for inflammatory cells and ICAM-1 was performed. Some additional clinical parameters were also recorded: days of school absence, extra visits for acute respiratory symptoms, and days of hospital admission. RESULTS: Only children treated with terfenadine achieved significant control of symptoms (P<0.05 in 8 out of 12 months) and allergic inflammation, as shown by inflammatory cell infiltrate and ICAM-1 expression at nasal level (P<0.001), and had significantly fewer extra visits and school absences than the placebo group (P<0.03). No side-effects were reported in either group. CONCLUSIONS: The present study demonstrates that continuous terfenadine treatment (1 mg/kg body weight per day) could decrease respiratory symptoms and allergic inflammation, and it had an additional antiallergic effect in reducing ICAM-1 expression on nasal epithelial cells. Therefore, the present results confirm the efficacy of a long-term therapeutic strategy in controlling allergic inflammation. 相似文献
86.
87.
The presence of chorionic gonadotrophin beta subunit in normal cyclic human endometrium 总被引:2,自引:1,他引:1
Wolkersdorfer GW; Bornstein SR; Hilbers U; Zimmermann G; Biesold C; Lehmann M; Alexander H 《Molecular human reproduction》1998,4(2):179-184
The aim of the present study was to determine whether human endometrial
cells are able to secrete beta-chorionic gonadotrophin (betaCG).
Immunohistochemical studies and in-situ hybridization were performed in
order to provide evidence for the occurrence of betaCG in the normal
endometrium in 15 patients in the proliferative phase, two patients in the
periovulatory phase and 13 patients in the secretory phase. Neither
immunohistochemical nor hybridization reactions could be recognized during
the proliferative phase. In contrast, both protein and betaCG mRNA were
observed in the glandular cells of the endometrium during the secretory
phase. The results were supported by Western blotting of secretory phase
endometrium extracts and the assessment of the functional secretory
capacity of primary endometrium cultures. In comparison with cultured and
separated cell fractions, tissue extracts showed a higher betaCG,
indicating a regulatory interaction. In conclusion, betaCG can be
demonstrated in normal human cyclic endometrium, suggesting a paracrine
role in endometrial physiology.
相似文献
88.
Lansteiner Award. Some aspects of serological specificity 总被引:1,自引:0,他引:1
GW Bird 《Transfusion》1990,30(5):390-400
89.
Rectal biopsy as a cause of rectal ulceration 总被引:1,自引:0,他引:1
90.
Avulsion fractures in the appendicular skeleton are a result of stress on a specific structure that is firmly attached to bone. A small avulsion fracture from the directly lateral surface of the lateral tibial condyle results from excessive tension on the lateral capsular ligament of the knee joint. Recognition of this fracture on an anteroposterior radiograph of a traumatized knee represents substantial evidence of major injury to the lateral joint capsule. This fracture also has a strong association with rupture of the anterior cruciate ligament. The avulsed tibial fragment is remarkably constant in site and appearance. The typical fragment is isolated by a longitudinal fracture line separating a small piece of bone from the lateral tibia. It is elliptical in outline (10 X 3 mm), with its proximal border lying 4 mm distal to the subarticular cortex of the lateral tibial condyle. A hemarthrosis of the knee joint is consistently visible. 相似文献