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51.
The coiled tail of the round-headed spermatozoa appears during epididymal passage in GOPC-deficient mice 总被引:4,自引:0,他引:4
Suzuki-Toyota F Ito C Toyama Y Maekawa M Yao R Noda T Toshimori K 《Archives of histology and cytology》2004,67(4):361-371
Male mice deleting the gene encoding GOPC (Golgi-associated PDZ- and coiled-coil motif-containing protein) are infertile, showing globozoospermia with a coiled tail (Yao et al., 2002). We confirmed how and where tail anomalies were produced in spermatids and epididymal spermatozoa by light and electron microscopy. During spermiogenesis, tail formation occurred normally, but a defect was found at the posterior ring. Thereafter, remarkable sperm tail deformations were induced during epididymal passage. In the proximal caput epidiymidis, the tails remained normal and straight, but most of them coiled around the nucleus in the cauda epididymidis. Coiling is presumed to occur with the migration of the cytoplasmic droplet by the absence of the posterior ring. The connecting piece of the coiled tail was often dislocated or separated from the implantation fossa. Many mitochondria were separated from the outer dense fibers (ODFs) and formed a stratified mitochondrial sheath. Due to this, the distal part of the midpiece became bared of the mitochondrial sheath. The bared ODFs were often bent and disorganized. Tail deformities are attributed to weak or incomplete adhesion between the following structures: 1) plasma membrane and nuclear envelope at the posterior ring, 2) connecting piece and implantation fossa, and 3) mitochondria and ODFs. These defects result in a coiled tail, tail dislocation from the implantation fossa, and the stratified mitochondrial sheath accompanying bared ODFs in the midpiece, respectively. Thus the posterior ring is significant in preventing coiled tail formation. The GOPC-deficient spermatozoa provide a valuable model not only for head but also for tail anomalies. 相似文献
52.
Maekawa M Ito C Toyama Y Suzuki-Toyota F Kimura T Nakano T Toshimori K 《Archives of histology and cytology》2004,67(4):335-347
A mouse homologue of Drosophila germ cell-less, mouse germ cell-less-1 (mgcl-1), is highly expressed in the testis. Previous report revealed that the fertility of the mgcl-1(-/-) male mice is reduced significantly as a result of various morphological abnormalities in the sperm (Kimura et al., 2003). To elucidate the function of mgcl-1 in spermatogenesis, the expression of mGCL-1 in the wild-type testis was examined. Immunohistochemical studies demonstrated that mGCL-1 first appeared in the nuclei of the pachytene spermatocytes at stage VI of the seminiferous epithelium, and existed in those of spermatids until step 8 during spermatogenesis. mGCL-1 was not detectable after step 9 spermatids. The testicular cells and epididymal sperm were further analyzed morphologically using mgcl-1(-/-) mice. In the testis, deformed nuclei first occurred in the pachytene spermatocytes at stage VI, which is consistent with the time of the first appearance of the mGCL-1 protein in the wild-type testis. Abnormal nuclei and acrosomes were found in spermatids after step 5, and nuclei of the spermatids and epididymal sperm were frequently invaginated. In addition, variously deformed sperm such as bent-neck, multi-headed or multi-nucleated sperm were observed in the mgcl-1(-/-) cauda epididymidis. However, several key structures such as the acroplaxome marginal ring (Kierszenbaum et al., 2003), postacrosomal sheath, and posterior ring apparently formed. In addition, MN7 and MN13, essential substances for fertilization that are located in sperm heads, were detectable in the mgcl-1 null sperm. These observations provide important insights into the mechanisms regulating the nuclear architecture and causes of human infertility. 相似文献
53.
Aotake T Yamamoto H Tanaka F Fujii H Hirose Y Matsushita T 《Gan to kagaku ryoho. Cancer & chemotherapy》2004,31(3):407-409
A 77-year-old man diagnosed with advanced gastric cancer underwent total gastrectomy with combined splenectomy and resection of the pancreatic tails in 1996. He was treated with 400 mg/day of UFT for 2 years. Serum CEA level was found to be elevated on July 5, 2001. He complained of left chest pain in December 2001. A 4 cm-sized tumor was detected in the region extending from the subcutaneous region to the left chest wall containing the osteolytic change of the left sixth rib. He was diagnosed with a chest wall metastasis from gastric cancer. He underwent radiotherapy with thermotherapy and was also treated with chemotherapy. TS-1 was administered at 80-100 mg/body/day, twice daily for 3 weeks followed by a 2-week rest interval as 1 cycle. As a results, shrinkage of the tumor was confirmed on February 14, 2002. The tumor was confirmed to have disappeared on April 17, 2002, by chest CT. A complete response of the metastatic tumor was achieved. The patient maintained a complete response for more than 12 months, but died from the chest wall metastasis recurrence and weakness on August 13, 2003. The only observed adverse event, was grade 2 leukopenia. 相似文献
54.
Kanatsu H Kitamikado H Sugihara S Kikukawa F Harada K Tani M Mori H Isobe K 《Gan to kagaku ryoho. Cancer & chemotherapy》2004,31(Z2):199-200
Due to social changes, advancement of medical technology and introduction of home care insurance, it has become a reality that a patient using an artificial respirator could be treated at home. We report specific problems associated with an ALS patient using an artificial respirator through home care support. A 68-year-old male had a back problem in 2001 and developed a sudden difficulty in breathing. Since 2002, the patient was forced to use an artificial respirator, and without taking his informed consent, was treated at home. Primary caregivers are his wife and daughter. The specific problems we identified are (1) patient's caregivers were unnecessary confused due to a lack of coordination between visiting nurses from two hospitals in giving home care treatment direction, (2) the care giver's burden tends to increase as the duration of care is extended because the short-stay facility or transferring system for patient is not well equipped, (3) there is no particular place to ask for assistance in case of an emergency or an established communication method as the patient's disease status will progress. It appears that these identified problems cannot be resolved by one hospital. However, we believe that we have to establish a community-wide home care system as quickly as possible. Meanwhile, it is important to have a nationwide coordination involving government, corporations, and political institutions to make it to be a success. 相似文献
55.
Nakahara M Koyama T Nakazawa F Nishio M Shibamiya A Hirosawa S 《Thrombosis and haemostasis》2004,92(6):1284-1290
Proteins that fail to attain their correct three-dimensional structure are retained in the endoplasmic reticulum (ER) and eventually degraded within the cells. We investigated the degradation of mutant proteins, using naturally occurring protein C (PC) mutants (Arg178Gln and Cys331Arg) which lead to congenital deficiencies. Chinese hamster ovary (CHO) cells were transfected with normal or mutant expression vectors. The introduction of mutation at Asn329 of an unusual sequence Asn-X-Cys for N-linked glycosylation revealed that the mutation at Cys331, which may preclude a formation of disulfide bond with Cys345, resulted in no addition of N-linked oligosaccharides at Asn329. PC mutants with 4 glycosylation sites were gradually glycosylated in the ER, and the fourth glycosylation site is less accessible for glycosylation as reported for PC in plasma. The half lives of PC178 and PC331 mutants were about 5 and 4 h, respectively. PC mutants were degraded, but the degradation was inhibited by inhibitors for proteasome. Mannose trimming of N-linked oligosaccharides after glucose removal targeted PC mutants for degradation by proteasomes. And also the inhibition of glucose trimming immediately led to mannose trimming, resulting in the accelerated degradation of PC mutants. These degradations were inhibited by mannosidase I inhibitor, kifunensine. These results indicate that the initiation of mannose trimming by mannosidase I leads to the proteasomemediated degradation of glucose-trimmed or untrimmed PC mutants. 相似文献
56.
Sawada H Nagahiro K Kikukawa Y Ban S Kakefuda R Shiomi T Yokosawa H 《Biological & pharmaceutical bulletin》2003,26(7):1025-1027
Duchenne muscular dystrophy is known to be caused by a defective gene of dystrophin, a 427-kDa cytoskeletal protein, but the effective therapeutic drug is presently unavailable. We previously reported that a trypsin-like protease designated as dystrypsin is markedly activated in the muscle microsomal fraction immediately before onset of the clinical signs in mdx mice, a dystrophin-deficient hereditary animal model for human Duchenne muscular dystrophy. In order to examine the possible participation of dystrypsin in the occurrence of the disease, we investigated the therapeutic effects of dystrypsin inhibitors on the occurrence and progress of muscular dystrophy. Here, we show that camostat mesilate, a low-molecular-weight inhibitor of trypsin-like proteases, including dystrypsin, is a candidate drug for Duchenne muscular dystrophy. 相似文献
57.
Effects of sesamin on aortic oxidative stress and endothelial dysfunction in deoxycorticosterone acetate-salt hypertensive rats 总被引:3,自引:0,他引:3
Nakano D Itoh C Ishii F Kawanishi H Takaoka M Kiso Y Tsuruoka N Tanaka T Matsumura Y 《Biological & pharmaceutical bulletin》2003,26(12):1701-1705
In the present study, we evaluated the relationship between the antihypertensive effect of sesamin, a lignan from sesame oil, and its antioxidative activity in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. After a 5-week treatment period, systolic blood pressure was significantly elevated in normal diet-fed DOCA-salt animals compared with cases in sham-operated animals. Sesamin feeding, tempol (a superoxide dismutase mimetic) treatment or antihypertensive drugs combination (triple therapy; reserpine, hydralazine, hydrochlorothiazide) significantly suppressed the development of DOCA-salt-induced hypertension. Compared with sham-operated rats, the normal diet-fed DOCA-salt rats revealed marked increases in aortic superoxide (O(2)(-)) production. These increases in O(2)(-) production were significantly suppressed by sesamin feeding or tempol treatment, but not by triple therapy. Acetylcholine (Ach)-induced endothelium-dependent relaxation was markedly decreased in normal diet-fed DOCA-salt rats, compared with cases in sham-operated rats. Sesamin feeding and triple therapy significantly improved the DOCA-salt-induced impairment of endothelium-dependent relaxation. However, tempol treatment had no effect on the impaired vasodilator responses induced by DOCA-salt treatment. In DOCA-salt rats with or without sesamin feeding, systolic blood pressure significantly correlated with both aortic O(2)(-) production and endothelium-dependent vascular relaxation. These findings suggest that sesamin feeding inhibits the enhancement of aortic O(2)(-) production in DOCA-salt hypertensive rats, and this effect may contribute to the antihypertensive effect of sesamin. Sesamin feeding-induced improvement of endothelial dysfunction seems to result from the above antioxidative and antihypertensive effects. 相似文献
58.
59.
60.
Mori H Abe F Furukawa S Furukawa S Sakai F Hino M Fujii T 《The Journal of antibiotics》2003,56(2):80-86
FR235222, a novel immunosuppressant which possesses potent inhibitory effects on the activity of mammalian histone deacetylases (HDACs), has been isolated from the fermentation broth of a fungus, Acremonium sp. No. 27082. FR235222 exhibited marked immunosuppressive effects on mouse ex vivo splenic T-lymphocyte proliferation, mouse delayed type hypersensitivity (DTH) response, rat adjuvant-induced arthritis (AA) and rat heterotopic cardiac transplantation. These results showed potential clinical use of this compound as a new type immunosuppressant in the fields of autoimmune diseases and organ transplantations. 相似文献