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991.
992.
Sugimoto M Sasaki S Watanabe T Nishimura S Ideta A Yamazaki M Matsuda K Yuzaki M Sakimura K Aoyagi Y Sugimoto Y 《PloS one》2010,5(11):e13817
Ionotropic glutamate receptors mediate most excitatory neurotransmission in the central nervous system by opening ion channels upon the binding of glutamate. Despite the essential roles of glutamate in the control of reproduction and anterior pituitary hormone secretion, there is a limited understanding of how glutamate receptors control ovulation. Here we reveal the function of the ionotropic glutamate receptor AMPA-1 (GRIA1) in ovulation. Based on a genome-wide association study in Bos taurus, we found that ovulation rate is influenced by a variation in the N-terminal leucine/isoleucine/valine-binding protein (LIVBP) domain of GRIA1, in which serine is replaced by asparagine. GRIA1(Asn) has a weaker affinity to glutamate than GRIA1(Ser), both in Xenopus oocytes and in the membrane fraction of bovine brain. This single amino acid substitution leads to the decreased release of gonadotropin-releasing hormone (GnRH) in immortalized hypothalamic GT1-7 cells. Cows with GRIA1(Asn) have a slower luteinizing hormone (LH) surge than cows with GRIA1(Ser). In addition, cows with GRIA1(Asn) possess fewer immature ovarian follicles before superovulation and have a lower response to hormone treatment than cows with GRIA1(Ser). Our work identified that GRIA1 is a critical mediator of ovulation and that GRIA1 might be a useful target for reproductive therapy. 相似文献
993.
Purpose
Microsatellite instability (MSI) is used to screen colorectal cancers (CRC) for Lynch Syndrome, and to predict outcome and response to treatment. The current technique for measuring MSI requires DNA from normal and neoplastic tissues, and fails to identify tumors with specific DNA mismatch repair (MMR) defects. We tested a panel of five quasi-monomorphic mononucleotide repeat markers amplified in a single multiplex PCR reaction (pentaplex PCR) to detect MSI.Experimental Design
We investigated a cohort of 213 CRC patients, comprised of 114 MMR-deficient and 99 MMR-proficient tumors. Immunohistochemical (IHC) analysis evaluated the expression of MLH1, MSH2, PMS2 and MSH6. MSI status was defined by differences in the quasi-monomorphic variation range (QMVR) from a pool of normal DNA samples, and measuring differences in allele lengths in tumor DNA.Results
Amplification of 426 normal alleles allowed optimization of the QMVR at each marker, and eliminated the requirement for matched reference DNA to define MSI in each sample. Using ≥2/5 unstable markers as the criteria for MSI resulted in a sensitivity of 95.6% (95% CI = 90.1–98.1%) and a positive predictive value of 100% (95% CI = 96.6%–100%). Detection of MSH6-deficiency was limited using all techniques. Data analysis with a three-marker panel (BAT26, NR21 and NR27) was comparable in sensitivity (97.4%) and positive predictive value (96.5%) to the five marker panel. Both approaches were superior to the standard approach to measuring MSI.Conclusions
An optimized pentaplex (or triplex) PCR offers a facile, robust, very inexpensive, highly sensitive, and specific assay for the identification of MSI in CRC. 相似文献994.
Psychological effects of Helicobacter pylori‐associated atrophic gastritis in patients under 50 years: A cross‐sectional study 下载免费PDF全文
995.
Effects of elevated seawater temperature and phosphate enrichment on the crustose coralline alga Porolithon onkodes (Rhodophyta) 下载免费PDF全文
Both global and local environmental changes threaten coral reef ecosystems. To evaluate the effects of high seawater temperature and phosphate enrichment on reef‐building crustose coralline algae, fragments of Porolithon onkodes were cultured for 1 month under laboratory conditions. The calcification rate of the coralline algae was not affected at 30°C, but it decreased to the negatives at 32°C in comparison to the control treatment of 27°C, indicating that the temperature threshold for maintaining positive production of calcium carbonate lies between 30 and 32°C. Phosphate enrichment of 1–2 μmol L ?1 did not affect the calcification rate. The net oxygen production rate was enhanced by phosphate enrichment, suggesting that the photosynthetic rate was limited by the availability of phosphate. It was concluded that moderate phosphate enrichment does not directly deteriorate algal calcification but instead ameliorates the negative effects of high seawater temperature on algal photosynthesis. 相似文献
996.
Le My Phuong Christian Damsgaard Do Thi Thanh Huong Atsushi Ishimatsu Tobias Wang Mark Bayley 《Ichthyological Research》2017,64(1):84-92
Fish anaesthesia is used to minimize handling stress and damage during harvesting, transportation, and surgical procedures. Through depression of cardiovascular and respiratory functions, it causes significant changes in blood gases and pH. Here, we present the effects of benzocaine (100 mg l?1), MS-222 (100 mg l?1), and Aqui-S (30 mg l?1) on blood gases and haematological parameters of commercial-sized (≈1 kg) striped catfish (Pangasianodon hypophthalmus) and the time course of recovery. Blood was taken through a dorsal aorta catheter immediately after catheterization, and regularly during the following 72 h recovery in aerated water. All anaesthetics caused increases in PCO2 and lactate resulting in a decrease in pHe, closely mirrored by RBC pHi, as well as a marked rise in Hct, associated with elevated [cortisol] and [glucose] and increased RBC counts but no change in RBC volume, as confirmed by the lack of an adrenergic response of RBC in vitro. All anaesthetics showed similar efficacy and blood parameters were normalized within 24 to 48 h. 相似文献
997.
Underwater observations of two living individuals and an examination of a freshly dead individual of the rare deep-sea fish Triodon macropterus revealed that they usually have the large ventral flap completely uplifted and seamlessly retracted into the abdominal region of the trunk: one individual was collected at a depth of 280 m by hook and line east of Tonaki-jima Island, Ryukyu Islands, and kept in a tank at the Okinawa Churaumi Aquarium for six years; the second living individual was observed by the ROV Hakuyo 2000 at a depth of 275 m east of Ishigaki-jima Island, Ryukyu Islands; and another individual collected at depths of 250?350 m by hook and line off Funchu Point, Yoron-jima Island (27°00.15’N, 128°26.06’E), Ryukyu Islands, provided an opportunity to demonstrate that the ventral flap could be manually uplifted by rotating the pelvis. When the ventral flap was uplifted in all of these specimens, whether naturally or manually, there were no scaleless linear bands or streaks and gaps evident in the skin between the retracted ventral flap and the abdominal region. The fine structure of the scales of the body and the ventral flap was observed by light microscopy, scanning electron microscopy, and X-ray CT scanning. The scales of the ventral flap are arranged in rows radiating from the antero-dorsal part of the ventral flap where the anterior part of the pelvis articulates with and rotates around the pectoral girdles. The orientation of the rows on the ventral flap changes from a posterior direction dorsally to a posteroventral direction more ventrally. A ridge with many sharp serrations is raised and bent from the edge of each scale on the body and ventral flap. The raised ridges on the lower scales on the ventral flap become packed together with the upper scales to form a seamless surface when the ventral flap is uplifted into the abdominal region. 相似文献
998.
Preservation of chromosomal integrity in murine spermatozoa derived from gonocytes and spermatogonial stem cells surviving prenatal and postnatal exposure to γ‐rays in mice 下载免费PDF全文
999.
Satoshi Minami Takeshi Yamamoto Atsushi Takahashi Tomoko Namba Jun Matsuda 《Autophagy》2017,13(10):1629-1647
Macroautophagy/autophagy is a self-degradation process that combats starvation. Lipids are the main energy source in kidney proximal tubular cells (PTCs). During starvation, PTCs increase fatty acid (FA) uptake, form intracellular lipid droplets (LDs), and hydrolyze them for use. The involvement of autophagy in lipid metabolism in the kidney remains largely unknown. Here, we investigated the autophagy-mediated regulation of renal lipid metabolism during prolonged starvation using PTC-specific Atg5-deficient (atg5-TSKO) mice and an in vitro serum starvation model. Twenty-four h of starvation comparably induced LD formation in the PTCs of control and atg5-TSKO mice; however, additional 24 h of starvation reduced the number of LDs in control mice, whereas increases were observed in atg5-TSKO mice. Autophagic degradation of LDs (lipophagy) in PTCs was demonstrated by electron microscopic observation and biochemical analysis. In vitro pulse-chase assays demonstrated that lipophagy mobilizes FAs from LDs to mitochondria during starvation, whereas impaired LD degradation in autophagy-deficient PTCs led to decreased ATP production and subsequent cell death. In contrast to the in vitro assay, despite impaired LD degradation, kidney ATP content was preserved in 48-h starved atg5-TSKO mice, probably due to increased utilization of ketone bodies. This compensatory mechanism was accompanied by a higher plasma FGF21 (fibroblast growth factor 21) level and its expression in the PTCs; however, this was not essential for the production of ketone bodies in the liver during prolonged starvation. In conclusion, lipophagy combats prolonged starvation in PTCs to avoid cellular energy depletion. 相似文献
1000.
Keitaro?TanoiEmail author Natsuko?I.?Kobayashi Takayuki?Saito Naoko?Iwata Risa?Kamada Ren?Iwata Hisashi?Suzuki Atsushi?Hirose Yoshimi?Ohmae Ryohei?Sugita Tomoko?M.?Nakanishi 《Plant and Soil》2014,384(1-2):69-77