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31.
本文测定了24例正常月经妇女在不同时相、不同大小卵泡的卵泡液中雌二醇(E_2)、孕酮(P_0)、雄烯二酮(A)、睾酮(T)、卵泡刺激素(FSH)、黄体生成素(LH)和催乳素(PRL)的含量,并分析其与外周血中相应激素浓度的关系。测定结果显示:小卵泡的卵泡液中E_2、Po,FSH,LH水平低于大卵泡中水平,而A和T水平则相反。排卵前大卵泡中E_2(9815nmol/L),P_0(3316nmol/L),FSH(1.34IU/L)和LH(3.9lIU/L)达最高值。A(280nmol/L)和T(137nmol/L)却较小卵泡中水平低(相应为692nmol/L和176nmol/L)。PRL水平在大小卵泡中无显著性差异。卵泡液中甾体激素水平高于外周血7—20.000倍,FSH、LH水平为外周血的10—80%,PRL水平为60%—3倍。 相似文献
32.
Roger A. Hoffman Peter Habeeb Gerald R. Buzzell 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,160(3):269-275
Summary Long-term increased or decreased circulating levels of thyroid hormones significantly modify porphyrin concentrations and morphology in the Harderian glands of male and female hamsters. Administration of T3 reduced porphyrin concentrations in females; this treatment or decreasing thyroid hormone levels with KClO4 suppressed the post-castration rise of porphyrins in males. Hypophysectomy led to increased porphyrins in the Harderian glands of males; this rise was suppressed in hypophysectomized males by T3 or T4. In females, hypophysectomy reduced porphyrins which were further reduced by daily administration of T3 or T4. These modifications in the normal females were identical in castrated males. Mitotic activity in the Harderian glands of females was stimulated by KClO4 and by hypophysectomy with or without exogenous T3. In males, castration increased mitotic activity which was suppressed by T3 and exacerbated by KClO4. Increased mitotic activity seemingly follows loss of tissue mass. The data show that thyroid hormones act directly on the Harderian glands rather than indirectly through modification of TSH synthesis/release. Female type glands in males are a consequence of loss of gonadal androgens by castration, or by suppression or loss of thyroid hormones by hypophysectomy or by treatment with KClO4. However, male type glands in females are the result of androgen treatment, and/or increased levels of thyroid hormones via reduced ambient temperatures or of photic input. We conclude that regulation of the Harderian gland appears to be different in the two sexes.Abbreviations
T
3
Triiodothyronine
-
T
4
Thyroxine
-
TSH
Thyroid Stimulating Hormone
-
KClO
4
Potassium Perchlorate
-
h
hours
-
ml
milliliter
-
mg
milligram
-
g
gram
-
male
-
female
-
castrated male
- AP
hypophysectomized
-
CON
Control
-
ALA
delta aminole-vulenic acid
-
HG
Harderian Gland 相似文献
33.
J.C. Hervé F. Pluciennik F. Verrecchia B. Bastide B. Delage M. Joffre J. Délèze 《The Journal of membrane biology》1996,149(3):179-187
17β-estradiol propionate was found to reduce the gap junctional communication in a concentration range similar to that of
testosterone propionate, in primary cultures of rat Sertoli cells and cardiac myocytes. Uncoupling was reversible on washing
out and occurred without concomitant rise in the intracellular calcium concentration.
Esterification was a prerequisite for the activity of extracellularly applied steroid compounds (for example, testosterone
was ineffective even at external concentrations up to 100 μm, whereas its intracellular application at 1 μm totally interrupted intercellular communication), but their uncoupling efficiency did not depend on the nature of the ester
chain nor on its position on the steroid nucleus. The derivatives of two other androgen hormones (derivatives of the androstane
nucleus) were also efficient as junctional uncouplers. Among five steroid molecules belonging to the pregnane family, only
one (pregnanediol diacetate) interrupted the junctional communication. Neither cholic acid nor cholesteryl acetate or ouabain
showed this effect. Altogether, no correlation with the presence or position of double bonds nor with the trans- or cis-fusion of the A and B rings could be recognized.
These results suggest that this reversible, nondeleterious uncoupling effect of steroids is independent of the shape of the
molecules and is more probably related to their size and liposolubility, that condition their insertion into the lipid bilayer.
Their incorporation into the membrane could disturb the activity of the membrane proteins by a physical mechanism.
Received: 10 April 1995/Revised: 27 October 1995 相似文献
34.
Selenium,zinc, and thyroid hormones in healthy subjects 总被引:3,自引:0,他引:3
Oliviero Olivieri Domenico Girelli Anna Maria Stanzial Luigi Rossi Antonella Bassi Roberto Corrocher 《Biological trace element research》1996,51(1):31-41
Iodothyronine 5′ deiodinase, which is mainly responsible for peripheral T3 production, has recently been demonstrated to be a selenium (Se)-containing enzyme. The structure of nuclear thyroid hormone
receptors contains Zinc (Zn) ions, crucial for the functional properties of the protein. In the elderly, reduced peripheral
conversion of T4 to T3 with a lower T3/T4 ratio and overt hypothyroidism are frequently observed. We measured serum Se and RBC GSH-Px (as indices of Se status), circulating
and RBC Zinc (as indices of Zn status), thyroid hormones and TSH in 109 healthy euthyroid subjects (52 women, 57 men), carefully
selected to avoid abnormally low thyroid hormone levels induced by acute or chronic diseases or calorie restriction. The subjects
were subdivided into three age groups. To avoid under- or malnutrition conditions, dietary records were obtained for a sample
of 24 subjects, randomly selected and representative of the whole population for age and sex. Low T3/T4 ratios and reduced Se and RBC GSH-Px activity were observed only in the older group. A highly significant linear correlation
between the T3/T4 ratio and indices of Se status was observed in the older group of subjects (r=0.54;p<0.002, for Se;r=0.50;p<0.002, for RBC GSH-Px). Indices of Zn status did not correlate with thyroid hormones, but RBC Zn was decreased in older as
compared with younger subjects. We concluded that reduced peripheral T4 conversion is related to impaired Se status in the elderly. 相似文献
35.
Mike H. Jurke 《Primates; journal of primatology》1996,37(1):109-119
The fate of most nonhuman primate species is intimately related to man. The increasing encroachment on the natural habitat
has resulted in the decimation and even near extinction of some species. Along with this development, the basic concept in
many modern zoos has changed from one of merely display to self-perpetuating units. Primate research facilities are orienting
their research programs towards reproductive physiology and behavior in an effort to provide basic knowledge of reproduction
in these species. This increased emphasis in the area of reproductive biology and the various efforts to improve breeding
of these mostly endangered primates in captivity has stimulated the author to write this review. It represents an attempt
to provide the reader with basic background information relating to the endocrinology and behavior of reproduction in the
clawed New World monkeys as it exists at the time of publication.
The intermediate evolutionary position ofCallimico goeldii between the clawed New World monkeys and the ‘true New World monkeys’ and our relatively poor knowledge about reproduction
and behavior in this particular species fully justifies the focus on Goeldi’s monkey in this essay. This review is an attempt
to provide a brief history of previous studies but also the basis for research in the future. The current status of knowledge
of the small-bodied clawed monkeys is also discussed in an evolutionary context, with an emphasis on the different reproductive
strategies in this dynamic group of primates.
The outcome, not surprisingly, confirms the unique position ofCallimico goeldii in its social, ecological, and evolutionary environment. 相似文献
36.
Y. Fukui T. Mogoe Y. G. Jung Y. Terawaki A. Miyamoto H. Ishikawa Y. Fujise S. Ohsumi 《Marine Mammal Science》1996,12(1):28-37
Spermatozoa from 21 mature minke whales ( Balaenoptera acutorostrata ) taken in the Antarctic Ocean for Japanese research were recovered from vasa deferentia, diluted 1:9 in a Tris-based diluent, and frozen at - 80°C on board the vessel. After a period ranging from 45 to 125 d, the samples were transferred to liquid nitrogen and transported to the laboratory. After thawing at 37°C the motility (percentage of motile spermatozoa), vitality (proportion of live spermatozoa), and sperm concentration were determined for each sample. These values were tested for correlations with morphological measurements (body size, body weight, testis weight) and serum concentrations of progesterone (Pd), estradiol-17β (E2), and testosterone (T). Ten of 21 samples had motile spermatozoa (2%-40%). Although no motile spermatozoa were observed in 1.1 samples, all sperm samples were examined by eosinnigrosin staining and showed vitality levels of 3%44%. It was found that the motility (Y = 0.54) and vitality (r = 0.53) of the spermatozoa were significantly (P < 0.01) correlated with the E2 levels (8.50 ± 1.80 pg/ml). Serum T levels (0.07 ± 0.02 ngml) were significantly correlated with the E2 levels (r = 0.58, P < 0.01>, but sperm concentrations were not correlated with either Ea or T levels. The present study demonstrates that spermatozoa of minke whales can be successfully cryopreserved. 相似文献
37.
T. C. Hu A. Ziauddin E. Simion K. J. Kasha 《In vitro cellular & developmental biology. Plant》1995,31(2):79-83
Significant improvements were achieved in the production of haploid and doubled haploid plants from isolated microspore culture
of wheat c.v. Chris on a defined media. Procedures found to be of benefit included: A 7-day pretreatment of anthers in 0.4M mannitol plus the macronutrients from FHG medium; the inclusion of 4.5 mg/liter abscisic acid in the pretreatment solution;
the isolation of microspores from pretreated anthers by vortexing; and the use of phenylacetic acid (PAA) as the auxin source
in MS medium. The best response was achieved with 4.0 mg/liter PAA in MS medium containing 90 g/liter maltose as the sugar
source. Under these conditions, 68% of viable microspores underwent division, and an average of 93 embryos and 92 green plants
were regenerated per 100 anthers used. The root-tip chromosome number and the fertility of 114 regenerating green plants revealed
that 75% were completely fertile spontaneously doubled haploids. 相似文献
38.
Iciar Martinez Bent Dreyer Aasta Agersborg Annick Leroux Gilles Boeuf 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1995,112(4)
Rearing of 1-year-old Arctic charr (Salvelinus alpinus) at 12°C, as well as the administration of 50 or 75 mgT3/kg feed, accelerated the neonatal to adult fast myosin heavy chain transition, but the effect of temperature was more dramatic than the effect of T3 administration. The endogenous plasma levels of T3 in charrs reared at 12°C were higher than those of analogous groups reared at natural temperature, which in the period under study was between 0.5 and 12°C. As in other species, T3 seemed to play a role in the regulation of the neonatal to adult fast myosin isoform transition by down-regulating the levels of the neonatal and increasing the levels of an adult fast myosin heavy chain. Temperature seemed to accelerate this transition at least, but not only, by inducing an increase in the endogenous levels of T3 in the Arctic charr. 相似文献
39.
Testicular weight and DNA content were markedly reduced (63 and 69%) in weanling Long-Evans rat pups rendered hypothyroid from birth by administration of propylthiouracil (PTU), a reversible goitrogen. These growth deficits worsened to >80% by continuing hypothyroidism beyond weaning, to days 50 and 90. Recovery of thyroid function, brought about by discontinuing PTU at weaning, resulted in a paradoxical stimulation of testis growth, amounting to increased weight (40%), DNA content (60%) and size by 90 days, compared to age-matched controls. In the 25-day or older hypothyroid rats, testicular structure was immature and spermatogenesis markedly delayed, as evident by closed lumen and significantly reduced diameter of seminiferous tubules (38%), thickness of germinal layer (70%), and number of primary spermatocytes (86%), compared to control. Hypothyroidism did not alter the number of tubules per testis cross section. In the 90-day recovery rats, numbers of seminiferous tubules were unchanged but tubular diameter was significantly (20%) larger than in controls and spermatogenesis appeared very active as indicated by significantly increased germinal layer thickness (22%) and total number and density of primary spermatocytes (55% and 40%). The results show that although postnatal hypothyroidism is deleterious for testicular growth and spermatogenesis, recovery from this condition leads to enhanced seminiferous tubular growth and spermatogenesis. 相似文献
40.
Milutin Miri Aleksandra Mikovi Sran Brki Jovan Vasiljevi Nenad Keserovi Milan Pei 《FEMS immunology and medical microbiology》1994,10(1):65-74
Abstract The randomized clinical trial with interferon-α (IFN) or thymic hormones versus conventional therapy was conducted in patients with myocarditis and idiopathic dilated cardiomyopathy (IDC). We enrolled 180 patients to receive IFN (3–5 million units per day) for 3 months, thymomodulin (10 mg three times per week) for 2 months, or conventional therapy alone. Patients were followed-up for 7 years after the end of treatment. Left ventricular function, exercise tolerance and survival rate were significantly better at long-term follow-up in patients treated with IFN or thymomodulin, than in conventionally treated patients. These results implicate that immune modulating therapy might represent important contribution in the treatment of myocarditis and IDC. 相似文献